Friday, December 24, 2021

SARS-CoV-2 Omicron variant




SARS-CoV-2 Omicron variant


This article needs more medical references for verification or relies too heavily on primary sources. (December 2021)



The Omicron variant is a variant of SARS-CoV-2, the virus that causes COVID-19. As of December 2021, it is the newest variant. It was first reported to the World Health Organization (WHO) from South Africa on 24 November 2021.[1] On 26 November 2021, the WHO designated it as a variant of concern and named it "Omicron", the fifteenth letter in the Greek alphabet.[2][3]

Omicron variant and other major or previous variants of concern of SARS-CoV-2 depicted in a tree scaled radially by genetic distance, derived from Nextstrain on 1 December 2021

The variant has an unusually large number of mutations, several of which are novel[4][5] (see § Mutations) and a significant number of which affect the spike protein targeted by most COVID-19 vaccines at the time of discovering the Omicron variant. This level of variation has led to concerns regarding its transmissibility, immune system evasion, and vaccine resistance, despite initial reports indicating that the variant causes less serious disease than previous strains. The variant was quickly designated as being "of concern", and travel restrictions were introduced by several countries in an attempt to slow its international spread.

Compared to previous variants of concern, Omicron is believed to be far more contagious (spreading much quicker),[6] and spreads around 70 times faster than any previous variants in the bronchi (lung airways), but it is less able to penetrate deep lung tissue, and perhaps for this reason there is a considerable reduction in the risk of severe disease requiring hospitalisation for most people.[7] However the extremely high rate of spread, combined with its ability to evade both double vaccination and the body's immune system, means that the total number of patients requiring hospital care at any given time is still of great concern.[7]

The new variant was first detected on 22 November 2021 in laboratories in Botswana and South Africa based on samples collected 11–16 November;[8][9] the first known sample was collected in South Africa on 8 November.[10][11] In other continents, the first known cases were a person arriving in Hong Kong from South Africa via Qatar on 11 November and another person who arrived in Belgium from Egypt via Turkey on the same date.[12][13] As of 16 December 2021, the variant has been confirmed in more than 80 countries, and in all continents except Antarctica.[14] The World Health Organization estimates that by mid-December, Omicron likely was in most countries in the world, whether they had detected it or not.[15]


























Classification
Nomenclature

On 26 November, the WHO's Technical Advisory Group on SARS-CoV-2 Virus Evolution declared PANGO lineage B.1.1.529 a variant of concern and designated it with the Greek letter omicron.[1][2][3] Greek letters are used to identify variants of SARS-CoV-2. The WHO skipped the preceding letters nu and xi in the Greek alphabet to avoid confusion with the similarities of the English word "new" and the Chinese surname Xi.[2][3][16][17] The previous designation was for the "variant of interest" mu.[18][19][3]

Possibly due to a lack of familiarity with the Greek alphabet among some English speakers and the relative frequency of the Latin prefix "omni" in other common speech, the name of the variant has also occasionally been mispronounced and misspelled as "Omnicron".[20]

The GISAID project has assigned it the clade identifier GR/484A,[21] and the Nextstrain project has assigned it the clade identifier 21K.[22]
Mutations



Genomic sequence
Defining mutations in the
SARS-CoV-2 Omicron variant
GeneAmino acid
ORF1ab nsp3: K38R
nsp3: V1069I
nsp3: Δ1265
nsp3: L1266I
nsp3: A1892T
nsp4: T492I
nsp5: P132H
nsp6: Δ105-107
nsp6: A189V
nsp12: P323L
nsp14: I42V
Spike A67V
Δ69-70
T95I
G142D,
Δ143-145
Δ211
L212I
ins214EPE
G339D
S371L
S373P
S375F
K417N
N440K
G446S
S477N
T478K
E484A
Q493R
G496S
Q498R
N501Y
Y505H
T547K
D614G
H655Y
N679K
P681H
N764K
D796Y
N856K
Q954H
N969K
L981F
E T9I
M D3G
Q19E
A63T
N P13L
Δ31-33
R203K
G204R
Sources: UK Health Security Agency[23] CoVariants[22]


The variant has many mutations, some of which have concerned scientists.[24] The Omicron variant has a total of 60 mutations compared to the original Wuhan variant: 50 nonsynonymous mutations, 8 synonymous mutations, and 2 non-coding mutations.[5] Thirty-two mutations affect the spike protein, the main antigenic target of antibodies generated by infections and of many vaccines widely administered. Many of those mutations had not been observed in other strains.[25][26] The variant is characterised by 30 amino acid changes, three small deletions, and one small insertion in the spike protein compared with the original virus, of which 15 are located in the receptor-binding domain (residues 319–541). It also carries a number of changes and deletions in other genomic regions. Additionally, the variant has three mutations at the furin cleavage site.[27] The furin cleavage site increases SARS-CoV-2 infectivity.[28] The mutations by genomic region are the following:[29][30]


Illustration of the locations of the Omicron mutations in the spike protein, top view (left) and side view (right), showing amino acid substitutions (yellow), deletions (red), and insertions (green). In this trimeric structure, two monomers (gray and light blue) have their receptor-binding domains in the "down" conformation while one (dark blue) is in the "up" or "open" conformation. Mutation data from WHO,[1] structure from PDB: 6VYB​.[31]
Spike protein: A67V, Δ69-70, T95I, G142D, Δ143-145, Δ211, L212I, ins214EPE, G339D, S371L, S373P, S375F, K417N, N440K, G446S, S477N, T478K, E484A, Q493R, G496S, Q498R, N501Y, Y505H, T547K, D614G, H655Y, N679K, P681H, N764K, D796Y, N856K, Q954H, N969K, L981F
Half (15) of these 30 changes are located in the receptor binding domain-RBD (residues 319–541)
ORF1ab
nsp3: K38R, V1069I, Δ1265, L1266I, A1892T
nsp4: T492I
nsp5: P132H
nsp6: Δ105-107, A189V
nsp12: P323L
nsp14: I42V
Envelope protein: T9I
Membrane protein: D3G, Q19E, A63T
Nucleocapsid protein: P13L, Δ31-33, R203K, G204R

A link with HIV infection may explain a large number of mutations in the sequence of the Omicron variant.[32][citation needed] Indeed, in order to be affected by such a high number of mutations, the virus must have been able to evolve a long time without killing its host, nor being eliminated. One such situation occurs in people with a weakened immune system but receiving enough medical care to survive.[33] This is the case in HIV patients in South Africa, who represent more than 20% of the population.[34] Due to lack of access to clinics, fear of stigmatisation and disrupted healthcare, millions living with HIV in the region are not on effective HIV therapy. HIV prevention could be key to reducing the risk that uncontrolled HIV is driving the emergence of Covid variants.[35]

In addition, it is believed that one of these many mutations, comprising a 9-nucleotide sequence, may have been acquired from another type of virus (known as HCoV-229E), responsible for the common cold.[36] This is not entirely unexpected - at times, viruses within the body acquire and swap segments of genetic material from each other, and this is one common means of mutation.[36]
Sublineages and stealth variant

Researchers have established the existence of three sublineages of Omicron. The 'standard' sublineage is now referred to as BA.1​/B.1.1.529.1, and the two other sublineages are known as BA.2​/B.1.1.529.2 and BA.3​/B.1.1.529.3.[37]

All three can be detected by full sequencing, but BA.2 has been nicknamed 'Stealth Omicron' because it differs from the 'standard' variety by not having the characteristic S gene target failure (SGTF)-causing deletion (Δ69-70) by which many PCR tests are able to detect a case as an Omicron, or Alpha, variant. Thus, countries that primarily rely on SGTF for detection may overlook BA.2.[38] Some countries, including Denmark, use a variant qPCR that tests for several mutations, including Δ69-70, E484K, L452R and N501Y.[39] It can also distinguish Delta (the heavily dominant variant worldwide, prior to the spread of Omicron), which has L452R but not N501Y,[40] and all Omicron sublineages, which have N501Y but not L452R.[41][42] As of 19 December 2021, BA.2 appears to be very rare with about twenty known cases from half a dozen countries.[37][42] The third sublineage, BA.3, is also very rare and it does not represent the same potential problem in detection since it has the SGTF deletion (Δ69-70), similar to BA.1.[37][43]
Possible consequences

The WHO is concerned that a large number of mutations may reduce immunity in people who were previously infected and in vaccinated people. It is also possible the omicron variant might be more infective in this regard than prior variants. The effects of the mutations, if any, are unknown as of late November 2021. The WHO warns that health services could be overwhelmed especially in nations with low vaccination rates where mortality and morbidity rates are likely to be much higher, and urges all nations to increase COVID-19 vaccinations.[44]

Professor Paul Morgan, immunologist at Cardiff University, also recommends vaccination. Morgan said, "I think a blunting rather than a complete loss [of immunity] is the most likely outcome. The virus can't possibly lose every single epitope on its surface, because if it did that spike protein couldn't work any more. So, while some of the antibodies and T cell clones made against earlier versions of the virus, or against the vaccines may not be effective, there will be others, which will remain effective. (...) If half, or two-thirds, or whatever it is, of the immune response is not going to be effective, and you're left with the residual half, then the more boosted that is the better."[45]

Professor Francois Balloux of the Genetics Institute at University College London said, "From what we have learned so far, we can be fairly confident that – compared with other variants – Omicron tends to be better able to reinfect people who have been previously infected and received some protection against COVID-19. That is pretty clear and was anticipated from the mutational changes we have pinpointed in its protein structure. These make it more difficult for antibodies to neutralise the virus."[46]

On 15 December, the European Centre for Disease Prevention and Control assessed that, even if the variant turns out to be milder than Delta, its spread will very likely increase hospitalizations and fatalities due the exponential growth in cases caused by increased transmissibility.[47]
Signs and symptoms
Main article: Symptoms of COVID-19

As of 28 November 2021 the World Health Organization's update states "There is currently no information to suggest that symptoms associated with Omicron are different from ... other variants".[48]

A study performed between the first of December to the 7th of December by the Center for Disease Control found that "The most commonly reported symptoms [were] cough, fatigue, and congestion or runny nose".[49]

Research published in London on 25 December 2021 suggested, the most frequent symptoms stated by users of the Zoe Covid app were "a running nose, headaches, fatigue, sneezing and sore throats."[50]
Characteristics

Many of the mutations to the spike protein are present in other variants of concern and are related to increased infectivity and antibody evasion. Computational modeling suggests that the variant may also escape cell-mediated immunity.[26] On 26 November, the ECDC wrote that an evaluation of the neutralizing capacity of convalescent sera and of vaccines is urgently needed to assess possible immune escape, saying these data are expected within two to three weeks.[30]
Contagiousness

It was not known in November 2021 how the variant would spread in populations with high levels of immunity. It was also not known if the omicron variant causes a milder or more severe COVID-19 infection. According to pharmaceutical companies, vaccines could be updated to combat the variant "in around 100 days" if necessary.[51]

Relating to naturally acquired immunity, Anne von Gottberg, an expert at the National Institute for Communicable Diseases, believed at the beginning of December 2021 that immunity granted by previous variants would not protect against Omicron.[52]

On 15 December 2021 Jenny Harries, head of the UK Health Security Agency, told a parliamentary committee that the doubling time of COVID-19 in most regions of the UK was now less than two days, despite the majority of the population being vaccinated. She said that the Omicron variant of COVID-19 is "probably the most significant threat since the start of the pandemic", and that the number of cases in the next few days would be "quite staggering compared to the rate of growth that we've seen in cases for previous variants".[53]
Virulence

As of 28 November 2021 the World Health Organization's update states "There is currently no information to suggest that symptoms associated with Omicron are different from ... other variants". Increased rates of hospitalization in South Africa may be due to a higher number of cases, rather than any specific feature of the Omicron variant.[48]

On 4 December 2021, the South African Medical Research Council reported that from 14 to 29 November 2021 at a hospital complex in Tshwane, inpatients were younger than in previous waves and the ICU and oxygen therapy rates were lower than in earlier waves. These observations are not definitive and the clinical profile could change over the following two weeks, allowing for more accurate conclusions about disease severity.[54] Excess deaths nearly doubled in the week of 28 November, suggesting under-reporting, but the level was still much lower than that seen in the second wave in mid-January 2021.[55] On 12 December, director-general of the World Health Organization Tedros Adhanom asserted that it was wrong for people to consider Omicron as mild. This is because high exposure to previous infections in South Africa likely affects the clinical course of the new infections.[56]

On 20 December, a report by the Imperial College COVID-19 Response Team based on data from England, found that hospitalisation and asymptomatic infection indicators were not significantly associated with Omicron infection, suggesting at most limited changes in severity compared with Delta.[57] On 22 December, the team reported an approximately 41% (95% CI, 37–45%) lower risk of a hospitalization requiring a stay of at least 1 night compared to the Delta variant, and that the data suggest that recipients of 2 doses of the Pfizer–BioNTech, the Moderna or the Oxford–AstraZeneca vaccine remain substantially protected from hospitalization.[58]
Diagnosis
See also: COVID-19 testing

The FDA has published guidelines on how PCR tests will be affected by Omicron.[59] Tests that detect multiple gene targets will continue to identify the testee as positive for COVID-19. S-gene dropout or target failure has been proposed as a shorthand way of differentiating Omicron from Delta.

The variant may be identified by sequencing and genotyping.[60] The BA.1 lineage, but not the BA.2 lineage, can be identified by S gene target failure (SGTF) of the TaqPath assay, a trait shared with subsets of SARS-CoV-2 Alpha variant.[38] Several other commercial assays can also be used, though they test for different amino acid substitutions.[a]
Prevention
See also: COVID-19 § Prevention

As with other variants, the WHO recommended that people continue to keep enclosed spaces well ventilated, avoid crowding and close contact, wear well-fitting masks, clean hands frequently, and get vaccinated.[1][61]

On 26 November 2021, BioNTech said it would know in two weeks whether the current vaccine is effective against the variant and that an updated vaccine could be shipped in 100 days if necessary. AstraZeneca, Moderna and Johnson & Johnson were also studying the variant's impact on the effectiveness of their vaccines.[62] On the same day, Novavax stated that it was developing an updated vaccine requiring two doses for the Omicron variant, which the company expected to be ready for testing and manufacturing within a few weeks.[63][64] On 29 November 2021, The Gamaleya Institute said that Sputnik Light should be effective against the variant, that it would begin adapting Sputnik V, and that a modified version could be ready for mass production in 45 days.[65] Sinovac said it could quickly mass-produce an inactivated vaccine against the variant and that it was monitoring studies and collecting samples of the variant to determine if a new vaccine is needed.[66] On 7 December 2021, at a symposium in Brazil with its partner Instituto Butantan, Sinovac said it would update its vaccine to the new variant and make it available in three months.[67] On December 2, the Finlay Institute was already developing a version of Soberana Plus against the variant.[68]

On 29 November 2021, the WHO said cases and infections are expected among those vaccinated, albeit in a small and predictable proportion.[69]

On 7 December 2021, preliminary results from a laboratory test conducted at the Africa Health Research Institute in Durban with 12 people who received the Pfizer-BioNTech vaccine found a 41-fold reduction in neutralizing antibody activity against the variant in some of the samples. This is a big reduction, but it does not mean that the variant can escape vaccines completely, so vaccination with current vaccines is still recommended. Neutralizing antibody activity against the variant was greater in those fully vaccinated after being infected about a year earlier. Effectiveness estimates will likely change as more data is collected, as antibodies generated by vaccination vary widely between individuals and the sample was small.[70][71][72] On 8 December 2021, Pfizer and BioNTech reported that preliminary data indicated that a third dose of the vaccine would provide a similar level of neutralizing antibodies against the variant as seen against other variants after two doses.[73]

On 10 December 2021, the UK Health Security Agency reported that early data indicated a 20- to 40-fold reduction in neutralizing activity for Omicron by sera from Pfizer 2-dose vaccinees relative to earlier strains and a 20-fold reduction relative to Delta. The reduction was greater in sera from AstraZeneca 2-dose vaccinees, falling below the detectable threshold. An mRNA booster dose produced a similar increase in neutralising activity regardless of the vaccine used for primary vaccination. After a booster dose (usually with an mRNA vaccine),[74] vaccine effectiveness against symptomatic disease was at 70%–75%, and the effectiveness against severe disease was expected to be higher.[75]

On 26 November 2021 the WHO asked nations to do the following:
Enhance surveillance and sequencing efforts to better understand circulating SARS-CoV-2 variants.
Submit complete genome sequences and associated metadata to a publicly available database, such as GISAID.
Report initial cases/clusters associated with virus-of-concern infection to WHO through the IHR mechanism.
Where capacity exists and in coordination with the international community, perform field investigations and laboratory assessments to improve understanding of the potential impacts of the virus of concern on COVID-19 epidemiology, severity, and the effectiveness of public health and social measures, diagnostic methods, immune responses, antibody neutralization, or other relevant characteristics.[76]
Treatment
See also: Treatment and management of COVID-19

Corticosteroids such as dexamethasone and IL6 receptor blockers such as tocilizumab (Actemra) are known to be effective for managing patients with the earlier strains of severe COVID-19. The impact on the effectiveness of other treatments was being assessed in 2021.[77][78]

On 29 November 2021, Pfizer CEO Albert Bourla said that Pfizer had submitted an Emergency Use Authorization application to the FDA for development of the RNA virus antiviral drug Paxlovid, and the company was confident that it could treat the Omicron variant.[79][medical citation needed] Merck and Ridgeback were evaluating the anti–RNA virus drug molnupiravir for omicron treatment at the time.[80]

Relating to monoclonal antibodies (mAbs) treatments, similar testing and research is ongoing. Preclinical data on in vitro pseudotyped virus data demonstrate that some mAbs designed to use highly conserved epitopes retain neutralizing activity against key mutations of Omicron substitutions.[81] Current data suggest Omicron would cause significant humoral immune evasion, while neutralizing antibodies targeting the sarbecovirus conserved region remain most effective.[82] Indeed, most receptor-binding motif (RBM)-directed monoclonal antibodies lost in vitro neutralizing activity against Omicron, with only 3 out of 29 mAbs retaining unaltered potency. Furthermore, a fraction of broadly neutralizing sarbecovirus mAbs neutralized Omicron through recognition of antigenic sites outside the RBM, including sotrovimab (VIR-7831), S2X259 and S2H97.[83]
Epidemiology

On 26 November 2021, the South African National Institute for Communicable Diseases announced that 30,904 COVID-tests (in one day) detected 2,828 new COVID infections (a 9.2% positivity rate).[84] One week later, on 3 December 2021, the NICD announced that 65,990 COVID tests had found 16,055 new infections (5.7 times as many as seven days before; positive rate 24.3%) and that 72 percent of them were found in Gauteng.[85][86] This province of South Africa is densely populated at about 850 inhabitants per km2. Gauteng's capital Johannesburg is a megacity (about 5.5 million inhabitants in the city itself plus 9.5 million in the urban region).

In November 2021 the transmissibility of the Omicron variant, as compared to the Delta variant or other variants of the COVID-19 virus, was still uncertain.[87] Omicron is frequently able to infect previously Covid-positive people.[88][89]

It has been estimated the Omicron variant diverged in late September or early October 2021, based on Omicron genome comparisons.[90] Sequencing data suggests that Omicron had become the dominant variant in South Africa by November 2021, the same month where it had been first identified in the country.[91][10] "Phylogeny suggests a recent emergence. Data from South Africa suggests that Omicron has a pronounced growth advantage there. However, this may be due to transmissibility or immune escape related, or both."[92]

Detectable changes in levels of COVID-19 in wastewater samples from South Africa's Gauteng province were seen as early as 17–23 October (week 42).[93] The National Institute for Communicable Diseases reports that children under the age of 2 make up 10% of total hospital admissions in the Omicron point of discovery Tshwane in South Africa.[94]

In the UK, the logarithmic growth rate of Omicron-associated S gene target failure (SGTF) cases over S gene target positive (SGTP) cases was estimated at 0.41 per day,[b] which is exceptionally high.[95] Furthermore, by 14 December it appears to have become the most dominant strain.[c][96] Without presuming behavior change in response to the variant, a million infections per day by December 24 are projected for a 2.5 days doubling time.[d][60] In Denmark, the growth rate has been roughly similar with a doubling time of about 2–3 days (with some geographical differences), it having reached about 39% of all COVID-19 cases on 14 December.[97][98] Switzerland is not far behind and neither is Germany.[99][100] In Scotland, Omicron apparently became the most prevalent variant on 17 December.[101][102] In Ontario it became the most prevalent strain on 13 December.[103] In the US, the variant appears to have become the most prevalent strain on December 13, growing at 0.42 per day.[104] This was one day before the CDC published the strain showed up in the variant surveillance.[105] In Belgium, the strain may become the most prevalent around 25 December,[106] and, the Netherlands appears to be on a similar path.[107][108] Other countries may not have enough timely information, as they may not use Thermo Fisher TaqPath Assay or equivalent for their PCR tests to indicate Omicron. Researchers recommend sampling at least 5% of COVID-19 patient samples in order to detect Omicron or other emerging variants.[109]

Data on the SGTF status of sampled cases in South Africa indicates a similar growth of 21% per day relative to Delta, generating an increased reproduction number by a factor of 2.4.[e] Omicron became the majority strain in South Africa around 10 November.[110][111] Another analysis showed 32% growth per day in Gauteng, South Africa, having become dominant there around 6 November.[112]
Statistics

Cumulative confirmed Omicron variant cases by country and territory

100,000–999,999
10,000–99,999
1,000–9,999
100–999
10–99
1–9
0

The chance of detecting a case particularly depends on a country's sequencing rate. For example, South Africa sequences far more samples than any other country in Africa, but at a considerably lower rate than most Western nations.[113][114] Furthermore it can take up to two weeks to return a viral sequence in places with the technical capability, hence solid statistics on confirmed cases lag the actual situation.[115] Denmark and Norway regard cases found by their variant qPCR test, which is relatively fast and checks several genes,[39] as sufficient for counting it as an Omicron, also before full sequencing.[116][117]
Confirmed and suspected cases by country and territory

view
talk
editCountry/TerritoryConfirmed cases (PANGOLIN)[118]
as of 22 DecemberConfirmed cases (GISAID)[119]
as of 22 DecemberConfirmed cases (other sources)
as of 22 DecemberSuspected cases
United Kingdom 8,207 34,573 114,625[120] 229,187[120]
Denmark 267 2,001 30,954[121]
Canada 58 586 8,046[122] 8,282[123]
Norway 179 308 5,240[116]
United States 937 7,346 7,355[124]
Germany 242 300 3,198[125][126]
South Africa 1,148 1,643 1,095[127] 19,070[128]
France 66 223 1,980[129]
Australia 296 859 1,109[130]
Estonia – – 1,513[131][132][133]
Argentina 2 3 455[134][135] 80[136]
Austria 10 332 419[137][138]
Israel 65 302 1,118[139] 861[139]
Botswana 256 291 23[140]
South Korea 9 9 445[141][142]
Sweden 38 303 260[143]
Belgium 147 460 121[137][144]
Switzerland 127 471 13[137]
India 353 68 400[145][146][147]
Japan 11 40 200[148]
Spain 68 417 51[125][144]
Netherlands 176 351 123[149][144]
Ireland 143 144 39[150]
Gibraltar 58 122 24[151]
Singapore 28 238 153[152][153][154]
Iceland – – 84[155]
Italy 42 209 84[156]
Chile 2 2 73[157][158]
Portugal 48 96 69[159][144] 6[160][137]
Thailand 10 14 205[161][162][163] 20[164]
Zimbabwe – – 50[165]
Ghana 35 66 33[140]
Brazil 22 47 36[166]
Finland 3 3 34[167][168][144]
Cyprus – – 31[169][170]
Morocco – 1 28[171] 46[171]
Kenya 10 27 27[172]
Russia 3 27 41[173][174]
Cayman Islands – – 44[175] 59[175]
Uganda – 1 25[176][177]
Mexico 3 42 1[178]
New Zealand – 29 22[179]
Namibia – 17 18[180]
Hong Kong 17 18 34[181]
Indonesia – 46 46[182]
Senegal – 26 3[183]
Mozambique 16 17 2[184] 2[124]
Greece 2 2 17[137][185]
Bermuda – – 144[186][187]
Latvia – – 14[188][144]
Romania 2 15 25[189][190][191]
Malaysia 2 11 62[192]
Zambia – 17 11[193]
Nigeria 11 45 6[194]
Czech Republic 9 39 10[137][195][144]
Slovenia 2 3 51[196][144][197]
Lebanon 4 4 433[198][199] 16[198]
Reunion 6 7 2[200]
Mauritius – 7 7[124]
Poland 2 18 1[173]
Rwanda – – 6[173]
Turkey 3 42 6[201]
Montenegro – 6 5[202]
Cambodia – 5 1[203]
Peru – 12 4[204]
Jordan – 19 328[205][206]
China – 3 4[207][208][209]
Cuba – – 4[210]
Croatia 2 8 3[137]
Egypt – 1 3[173]
Malawi 3 12 3[211]
Palestinian Territory – – 23[212]
Taiwan – – 27[213][214]
Lithuania 2 3 2[215]
Colombia – 3 3[216]
Slovakia 3 10 3[217]
Trinidad and Tobago – 3 1[218]
Puerto Rico – 23 1[219]
Fiji – – 2[220]
Nepal 2 3 2[221]
Philippines – 3 3[222][223]
Northern Cyprus – – 2[224]
Bangladesh 2 2 2[225]
Liechtenstein – 3 1[226] 3[124]
Hungary – – 61[227][144][228]
Oman – 9 2[229]
Pakistan – 3 1[230]
Sri Lanka 2 3 1[231]
Georgia 1 24[232][233] 53[233]
Algeria – 1 1[173]
Bahrain – – 1[234]
Ecuador – 22 1[235]
Kuwait – – 1[236]
Luxembourg – 1 1[137]
Maldives – 1 1[237]
Sierra Leone – 1 1[238]
Saudi Arabia – – 1[239]
Tunisia – – 1[240]
United Arab Emirates – – 1[241]
Iran – – 14[242][243]
Ukraine – 1 1[244]
Panama – 1 1[245]
Costa Rica – 1 1[246]
Aruba – – 1[247]
North Macedonia – – 1[248]
Brunei – 1 – –
Vietnam – 1 – –
World total (104 countries and territories) 8,340 16,561 173,482 257,848




History
Reported cases
See also: Timeline of the SARS-CoV-2 Omicron variant

On 24 November 2021, the variant was first reported to the WHO from South Africa,[1] based on samples that had been collected from 14 to 16 November.[249] South African scientists were first alerted by samples from the very beginning of November where the PCR tests had S gene target failure (occurs in a few variants, but not in Delta which dominated in the country in October) and by a sudden increase of COVID-19 cases in Gauteng; sequencing revealed that more than 70 percent of samples collected in the province between 14 and 23 November were a new variant.[250][251] The first confirmed specimens of Omicron were collected on 8 November 2021 in South Africa,[10][11] and on 9 November in Botswana.[26] Likely Omicron (SGTF) samples had occurred on 4 November 2021 in Pretoria, South Africa.[252]

When WHO was alerted on 24 November, Hong Kong was the only place outside Africa that had confirmed a case of Omicron; one person who traveled from South Africa on 11 November, and another traveler who was cross-infected by this case while staying in the same quarantine hotel.[251][253][254]

On 25 November, one confirmed case was identified in Israel from a traveler returning from Malawi,[255] along with two who returned from South Africa and one from Madagascar.[256] All four initial cases reported from Botswana occurred among fully vaccinated individuals.[257]

On 26 November, Belgium confirmed its first case; an unvaccinated person who had travelled from Egypt via Turkey on 11 November.[12][258][259] All three initial confirmed and suspected cases reported from Israel occurred among fully vaccinated individuals,[255] as did a single suspected case in Germany.[260]

On 27 November, two cases were detected in the United Kingdom, another two in Munich, Germany and one in Milan, Italy.[261]

On 28 November, 13 cases were confirmed in the Netherlands among the 624 airline passengers who arrived from South Africa on 26 November.[262] Confirmation of a further 5 cases among these passengers followed later.[263] Entry into the Netherlands generally required having been vaccinated or PCR-tested, or having recovered. The passengers of these two flights had been tested upon arrival because of the newly imposed restrictions (which were set in place during their flight), after which 61 tested positive for SARS-CoV-2.[264] A further two cases were detected in Australia. Both people landed in Sydney the previous day, and travelled from southern Africa to Sydney Airport via Doha Airport. The two people, who were fully vaccinated, entered isolation; 12 other travellers from southern Africa also entered quarantine for fourteen days, while about 260 other passengers and crew on the flight have been directed to isolate.[265] Two travellers from South Africa who landed in Denmark tested positive for COVID-19; it was confirmed on 28 November that both carried the Omicron variant.[266][267] On the same day, Austria also confirmed its first Omicron case.[268] A detected Omicron case was reported in the Czech Republic, from a traveler who spent time in Namibia.[269] Canada also reported its first Omicron cases, with two from travelers from Nigeria, therefore becoming the first North American country to report an Omicron case.[270]

On 29 November, a positive case was recorded in Darwin, Australia. The person arrived in Darwin on a repatriation flight from Johannesburg, South Africa on 25 November, and was taken to a quarantine facility, where the positive test was recorded.[271] Two more people who travelled to Sydney from southern Africa via Singapore tested positive.[272] Portugal reported 13 Omicron cases, all of them members of a soccer club.[273] Sweden also confirmed their first case on 29 November,[274] as did Spain, when a traveler came from South Africa.[275]

On 30 November, the Netherlands reported that Omicron cases had been detected in two samples dating back as early as 19 November.[276] A positive case was recorded in Sydney from a traveller who had visited southern Africa before travel restrictions were imposed, and was subsequently active in the community.[277] Japan also confirmed its first case.[278] Two Israeli doctors have tested positive and have entered isolation. Both of them had received three shots of the Pfizer vaccine prior to testing positive.[279] In Brazil, three cases of the Omicron variant were confirmed in São Paulo.[280] Another five are under suspicion.[281][282] A person in Leipzig, Germany with no travel history nor contact with travellers tested positive for Omicron.[283]

On 1 December, the Omicron variant was detected in three samples in Nigeria that had been collected from travelers from South Africa within the last week.[284][285] On the same day, public health authorities in the United States announced the country's first confirmed Omicron case. A resident of San Francisco who had been vaccinated returned from South Africa on 22 November, began showing mild symptoms on 25 November[286] and was confirmed to have a mild case of COVID-19 on 29 November.[287] Ireland and South Korea also reported their first cases.[288] South Korea reported its cases from five travelers arriving in South Korea from Nigeria.[289]

On 2 December, Dutch health authorities confirmed that all 14 passengers with confirmed Omicron infection on 26 November had been previously vaccinated.[290] The same day, the Norwegian Institute of Public Health confirmed that 50 attendees of a company Christmas party held at a restaurant in Norway's capital, Oslo, were infected with the Omicron variant.[291] France has confirmed only 25 cases of the new Omicron variant but officials say the number could jump significantly in the coming weeks.[292]

By 6 December, Malaysia confirmed its first case of the variant. The case was a South African student entering to study at a private university.[293] In Namibia, 18 cases out of 19 positive COVID-19 samples that had been collected between 11 and 26 November were found to be Omicron, indicating a high level of prevalence in the country.[294] Fiji also confirmed two positive cases of the variant. They travelled from Nigeria arriving in Fiji on November 25.[295]

On 8 December, WHO announced the variant had been detected in 57 countries.[296]

On 9 December, Richard Mihigo, coordinator of the World Health Organisation's Immunisation and Vaccine Development Programme for Africa, announced that Africa accounted for 46% of reported cases of the Omicron variant globally.[297]

On 13 December, the first death of a person with Omicron was reported in the UK.[298]

On 16 December, New Zealand confirmed its first case of the Omicron variant, an individual who had traveled from Germany via Dubai.[299]

On 23 December, the first death of a person with Omicron was reported in Germany.[126]
Market reactions
Main article: Financial market impact of the COVID-19 pandemic

Worry about the potential economic impact of the Omicron variant led to a drop in global markets on 26 November, including the worst drop of the Dow Jones Industrial Average in 2021, led by travel-related stocks. The price of Brent Crude and West Texas Intermediate oil fell 10% and 11.7%, respectively.[300] Cryptocurrency markets were also routed.[301][302][303] The South African rand has also hit an all-time low for 2021, trading at over 16 rand to the dollar, losing 6% of its value in November.[304][305][306]

In early December 2021, the chairman of the Federal Reserve, Jerome Powell, testified before the U.S. Senate Committee on Banking that "The recent rise in Covid-19 cases and the emergence of the Omicron variant pose downside risks to employment and economic activity and increased uncertainty for inflation."[307]
International response

On 26 November, WHO advised countries not to impose new restrictions on travel, instead recommending a "risk-based and scientific" approach to travel measures.[308] On the same day, the European Centre for Disease Prevention and Control (ECDC) reported modeling indicating that strict travel restrictions would delay the variant's impact on European countries by two weeks, possibly allowing countries to prepare for it.[30]

After the WHO announcement, on the same day, several countries announced travel bans from southern Africa in response to the identification of the variant, including the United States, which banned travel from eight African countries,[309] although it notably did not ban travel from any European countries, Israel, Canada, or Australia where cases were also detected at the time the bans were announced. Other countries that also implemented travel bans include Japan, Canada, the European Union, Israel, Australia, the United Kingdom, Singapore, Malaysia, Indonesia, Morocco, and New Zealand.[310][311]

The Brazilian Health Regulatory Agency recommended flight restrictions regarding the new variant.[312] The state of New York declared a state of emergency ahead of a potential Omicron spike, although no cases had yet been detected in the state or the rest of the United States.[313] On 27 November, Switzerland introduced obligatory tests and quarantine for all visitors arriving from countries where the variant was detected, which originally included Belgium and Israel.[314]

In response to the various travel bans, South African Minister of Health Joe Phaahla defended his country's handling of the pandemic and said that travel bans went against the "norms and standards" of the World Health Organization.[315]

Some speculate that travel bans could have a significant impact on South Africa's economy by limiting tourism and could lead to other countries with economies that are reliant on tourism to hide the discovery of new variants of concern. Low vaccine coverage in less-developed nations could create opportunities for the emergence of new variants, and these nations also struggle to gain intellectual property to develop and produce vaccines locally.[316] At the same time, inoculation has slowed in South Africa due to vaccine hesitancy and apathy, with only 35% of the population being fully vaccinated as of November 2021.[317]

On 29 November 2021, the WHO warned countries that the variant poses a very high global risk with severe consequences and that they should prepare by accelerating vaccination of high-priority groups and strengthening health systems. WHO director-general Tedros Adhanom described the global situation as dangerous and precarious and called for a new agreement on the handling of pandemics, as the current system disincentivizes countries from alerting others to threats that will inevitably land on their shores. CEPI CEO Richard Hatchett said that the variant fulfilled predictions that transmission of the virus in low-vaccination areas would accelerate its evolution.[69]

In preparation for the Omicron variant arriving in the United States, president Joe Biden has stated that the variant is "cause for concern, not panic" and reiterated that the government is prepared for the variant and will have it under control. He also stated that large-scale lockdowns, similar to the ones in 2020 near the beginning of the pandemic, are "off the table for now."[318]

In mid-December 2021, multiple Canadian provinces reinstated restrictions on gatherings and events such as sports tournaments, and tightened enforcement of proof of vaccination orders. British Columbia expressly prohibited any non-seated "organized New Year's Eve event",[319][320][321] while Quebec announced a partial lockdown on 20 December, ordering the closure of all bars, casinos, gyms, schools, and theatres, as well as imposing restrictions on the capacity and operating hours of restaurants, and the prohibition of spectators at professional sporting events.[322]
See also

COVID-19 portal
Medicine portal
Viruses portal
Timeline of the SARS-CoV-2 Omicron variant
COVID-19 pandemic in Africa
COVID-19 vaccination in Africa
COVID-19 vaccination in Botswana
COVID-19 vaccination in South Africa
Variants of SARS-CoV-2
Other variants of either interest or concern: Alpha, Beta, Gamma, Delta, Epsilon, Zeta, Eta, Theta, Iota, Kappa, Lambda, Mu

Notes

^ ECDC rapid risk assessment of Omicron,[47] annex 1.
^ Logarithmic growth rate of 0.41/day means that the log odds loge(SGTF/SGTP) is increasing by 0.41 in a day. So SGTF/SGTP was increasing by a multiplicative factor of exp(0.41) ~ 1.51. This is substantially higher than a naive increase to 100%+41%. The difference is mathematically due to compound growth within the day, which does not imply that epidemically people are already infectious within a day. Rather, simplified (non-delay) differential equations are used for convenience for the modeling. This also indicates a doubling time of log_e(2)/(0.41/day) ~ 1.69 days for the Omicron to Delta prevalence ratio.
^ Referring to ref 6 in the reference, where the x-axis is crossed at 14 December
^ A doubling time of 2.5 days corresponds to an exponential growth rate of ln(2)/(2.5 days) ~ 28%/day. Direct comparison to the logistic growth rate needs to take the growth/decline of Delta into account
^ With a presumed an identical person-to-person serial interval of log_e(2.4)/0.21 ~ 4.2 days, or a distribution thereof to the same effect.
References

^ a b c d e "Classification of Omicron (B.1.1.529): SARS-CoV-2 Variant of Concern". World Health Organization. 26 November 2021. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ a b c Parekh, Marcus; Platt, Poppie; Team, Global Health Security; Barnes, Joe (26 November 2021). "Coronavirus latest news: EU suspends all flights to southern Africa over omicron Covid variant fears". The Telegraph. ISSN 0307-1235. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ a b c d Meyer, David (26 November 2021). "What's Omicron? Here's what we know and don't know about the new COVID variant that's roiling markets and air travel". Fortune. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ Torjesen, Ingrid (29 November 2021). "Covid-19: Omicron may be more transmissible than other variants and partly resistant to existing vaccines, scientists fear". BMJ. 375: n2943. doi:10.1136/bmj.n2943. ISSN 1756-1833. PMID 34845008. S2CID 244715303. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ a b William A. Haseltine (2 December 2021). "Omicron Origins". Forbes. Archived from the original on 3 December 2021. Retrieved 4 December 2021.
^ Omicron: Good news, bad news and what it all means BBC
^ a b "Lung tissue study sheds light on fast Omicron spread". CIDRAP.
^ Melody Schrieber (16 December 2021). "The scientist in Botswana who identified omicron was saddened by the world's reaction". Goats and Soda. NPR. Retrieved 17 December 2021.
^ "Inside the South African lab that discovered Omicron". Africanews. 9 December 2021. Retrieved 17 December 2021.
^ a b c "Omicron becomes dominant variant in South Africa". The Guardian. 2 December 2021. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ a b "SARS-CoV-2 Sequencing Update 1 December 2021" (PDF). South African National Institute for Communicable Diseases. Archived (PDF) from the original on 1 December 2021. Retrieved 2 December 2021.
^ a b Lambrecht, Pieter (29 November 2021). "Wat weten we al over de nieuwe coronavariant, de omikron?" [What do we already know about the new coronavirus variant, Omicron?]. De Tijd (in Dutch). Belgium. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ Philip Whiteside (30 November 2021). "COVID-19: how the spread of Omicron went from patient zero to all around the globe". Sky News. Retrieved 17 December 2021.
^ "Enhancing Readiness for Omicron (B.1.1.529): Technical Brief and Priority Actions for Member States". WHO. 17 December 2021. Retrieved 19 December 2021.
^ "Omicron Probably In Most Countries, Spreading At Unprecedented Rate: WHO". NDTV. 15 December 2021. Retrieved 19 December 2021.
^ Patel, Vimal (27 November 2021). "How Omicron, the New Covid-19 Variant, Got Its Name". The New York Times. ISSN 0362-4331. Archived from the original on 28 November 2021. Retrieved 28 November 2021.
^ "There are several COVID-19 variants you haven't heard of". NewsNation Now. 27 November 2021. Archived from the original on 27 November 2021. Retrieved 27 November 2021.
^ "Tracking SARS-CoV-2 variants". World Health Organization. Retrieved 13 December 2021.
^ "Countries are scrambling to stop a new covid variant". The Economist. 26 November 2021. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ Tcholakian, Danielle (15 December 2021). "'Omni is everywhere': why do so many people struggle to say Omicron?". The Guardian. Retrieved 23 December 2021.
^ "In focus". gisaid.org. GISAID. 28 November 2021. Archived from the original on 21 January 2021. Retrieved 28 November 2021. The unique mix of spike amino acid changes in Omicron GR/484A (B.1.1.529) is of interest as it comprises several that were previously known to affect receptor binding and antibody escape.
^ a b "Variant: 21K (Omicron)". covariants.org. CoVariants. 28 November 2021. Archived from the original on 28 November 2021. Retrieved 28 November 2021. Variant 21K (Omicron) appears to have arisen in November 2021, possibly in South Africa.
^ "SARS-CoV-2 variants of concern and variants under investigation in England - Technical briefing 29" (PDF). gov.uk. UK Health Security Agency. 26 November 2021. p. 18. Retrieved 10 December 2021.
^ Hurst, Luke (26 November 2021). "What we know so far about the B.1.1.529 'Omicron' COVID variant causing concern". Euronews. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ Cookson, Clive; Barnes, Oliver (26 November 2021). "What we know about Omicron variant that has sparked global alarm". Financial Times. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ a b c Callaway, Ewen (25 November 2021). "Heavily mutated coronavirus variant puts scientists on alert". Nature. 600 (7887): 21. doi:10.1038/d41586-021-03552-w. PMID 34824381. S2CID 244660616. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ Zimmer, Carl (26 November 2021). "New Virus Variant Stokes Concern but Vaccines Still Likely to Work". New York Times. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ Zhang, Liping; Mann, Matthew; Zulfeqhar, Syed; Reynolds, Hayley; Tian, E; Samara, Nadine; Zeldin, Darryl; Tabak, Lawrence (23 November 2021). "Furin cleavage of the SARS-CoV-2 spike is modulated by O-glycosylation". Proceedings of the National Academy of Sciences of the United States of America. 118 (47): e2109905118. doi:10.1073/pnas.2109905118. PMC 8617502. PMID 34732583. S2CID 242937417.
^ SARS-CoV-2 variants of concern and variants under investigation in England, technical briefing 29 (PDF) (Briefing). Public Health England. 26 November 2021. GOV-10481. Archived (PDF) from the original on 27 November 2021. Retrieved 26 November 2021.
^ a b c "Implications of the emergence and spread of the SARS-CoV-2 B.1.1.529 variant of concern (Omicron) for the EU/EEA" (PDF). ecdc.europa.eu. Archived (PDF) from the original on 26 November 2021. Retrieved 26 November 2021.
^ Walls, Alexandra C.; Park, Young-Jun; Tortorici, M. Alejandra; Wall, Abigail; McGuire, Andrew T.; Veesler, David (April 2020). "Structure, Function, and Antigenicity of the SARS-CoV-2 Spike Glycoprotein". Cell. 181 (2): 281–292.e6. doi:10.1016/j.cell.2020.02.058. PMC 7102599. PMID 32155444.
^ "The birth of Omicron: Did HIV play a role?". www.medicalnewstoday.com. 6 December 2021. Retrieved 11 December 2021.
^ "The mystery of where omicron came from — and why it matters". NPR.org. 1 December 2021. Retrieved 8 December 2021.
^ "HIV and AIDS in South Africa". Avert. 21 July 2015. Retrieved 8 December 2021.
^ Sample, Ian (11 December 2021). "Why uncontrolled HIV may be behind the emergence of Omicron". The Guardian. Retrieved 12 December 2021.
^ a b "Fact Check-Omicron is not the common cold 'rebranded'". 10 December 2021 – via www.reuters.com.
^ a b c "Lineage B.1.1.529". PANGOLIN. 19 December 2021. Retrieved 19 December 2021.
^ a b Sample, Ian; Walker, Peter (7 December 2021). "Scientists find 'stealth' version of Omicron that may be harder to track". www.theguardian.com. Archived from the original on 7 December 2021. Retrieved 7 December 2021.
^ a b "Variant-PCR-testen (tidl. Delta-PCR-testen)" (in Danish). Statens Serum Institut. 7 June 2021. Retrieved 13 December 2021.
^ "Delta Variant Report". outbreak.info (Scripps Research). 13 December 2021. Retrieved 13 December 2021.
^ "BA.1 Lineage Report". outbreak.info (Scripps Research). 19 December 2021. Retrieved 19 December 2021.
^ a b "BA.2 Lineage Report". outbreak.info (Scripps Research). 19 December 2021. Retrieved 19 December 2021.
^ "BA.3 Lineage Report". outbreak.info (Scripps Research). 19 December 2021. Retrieved 19 December 2021.
^ Gregory, Andrew (29 November 2021). "Omicron Covid variant poses very high global risk, says WHO". The Guardian. London. Archived from the original on 29 November 2021. Retrieved 29 November 2021.
^ Geddes, Linda (29 November 2021). "What does appearance of Omicron variant mean for the double-vaccinated?". The Guardian. London. Archived from the original on 29 November 2021. Retrieved 29 November 2021.
^ Omicron: what do we know about the new Covid variant? Archived 5 December 2021 at the Wayback Machine The Guardian
^ a b Assessment of the further emergence and potential impact of the SARS-CoV-2 Omicron variant of concern in the context of ongoing transmission of the Delta variant of concern in the EU/EEA, 18th update (Technical report). Stockholm: European Centre for Disease Prevention and Control. 15 December 2021.
^ a b "Update on Omicron". World Health Organization. 28 November 2021. Archived from the original on 30 November 2021. Retrieved 30 November 2021.
^ CDC COVID-19 Response Team (17 December 2021). "SARS-CoV-2 B.1.1.529 (Omicron) Variant — United States, December 1–8, 2021". MMWR. Morbidity and Mortality Weekly Report. Center for Disease Control. 70 (50): 1731–1734. doi:10.15585/mmwr.mm7050e1. PMID 34914670. S2CID 245071514. Retrieved 17 December 2021.
^ Omicron’s cold-like symptoms mean UK guidance ‘needs urgent update’ The Guardian
^ New Covid variant: Will new measures against Omicron work? Archived 28 November 2021 at the Wayback Machine BBC
^ AFP (2 December 2021). "S. Africa expert: Previous infection doesn't protect against Omicron, but shots do". www.timesofisrael.com. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ "LIVE - Covid: 'Staggering' Omicron case numbers expected - top health official". BBC News. 15 December 2021. Retrieved 15 December 2021. See entry for 10:05
^ Abdullah, Fareed (4 December 2021). "Tshwane District Omicron Variant Patient Profile - Early Features". South African Medical Research Council. Archived from the original on 7 December 2021. Retrieved 7 December 2021.
^ "Omicron Wave Sees South Africa's Weekly Excess Deaths Almost Double". Bloomberg. 8 December 2021. Retrieved 11 December 2021.
^ "South Africa: previous infections may explain Omicron hospitalisation rate". The Guardian. 14 December 2021. Retrieved 14 December 2021.
^ Ferguson N, Ghani A, Cori A, Hogan A, Hinsley W, Volz E (20 December 2021). Growth, population distribution and immune escape of the Omicron in England (Technical report). WHO Collaborating Centre for Infectious Disease Modelling, MRC Centre for Global Infectious Disease Analysis. Imperial College London. doi:10.25561/93038. Report 49. Archived (PDF) from the original on 20 December 2021.
^ Ferguson N, Ghani A, Hinsley W, Volz E (22 December 2021). Hospitalisation risk for Omicron cases in England (Technical report). WHO Collaborating Centre for Infectious Disease Modelling, MRC Centre for Global Infectious Disease Analysis. Imperial College London. doi:10.25561/93035. Report 50. Archived (PDF) from the original on 23 December 2021.
^ "SARS-CoV-2 Viral Mutations: Impact on COVID-19 Tests". FDA. 16 December 2021. Retrieved 16 December 2021.
^ a b "SARS-CoV-2 variants of concern and variants under investigation in England" (PDF). Retrieved 10 December 2021.
^ Nebehay, Stephanie; Winning, Alexander (26 November 2021). "WHO names new COVID variant omicron, cautions against travel measures". Reuters. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ "BioNTech says it could tweak Covid vaccine in 100 days if needed". The Guardian. 26 November 2021. Archived from the original on 27 November 2021. Retrieved 27 November 2021.
^ "Novavax developing vaccine that targets new COVID-19 variant". CBS Baltimore Staff. 30 November 2021. Archived from the original on 2 December 2021. Retrieved 4 December 2021.
^ Maddipatla, Manojna; Roy, Mrinalika (26 November 2021). "Maryland-Based Vaccine Manufacturer Developing COVID-19 Vaccine That Targets Omicron Variant". Reuters. Archived from the original on 28 November 2021. Retrieved 30 November 2021.
^ "Sputnik V maker: Vaccine could be adapted to fight omicron". ABC News. Moscow. Associated Press. 29 November 2021. Retrieved 29 November 2021.
^ "Sinovac and world's Covid-19 vaccine makers 'ready' to produce Omicron jab". South China Morning Post. 29 November 2021. Archived from the original on 30 November 2021. Retrieved 29 November 2021.
^ "Sinovac prevê atualização da Coronavac para variante Ômicron em até três meses" [Sinovac plans to update Coronavac to the Omicron variant within three months]. CNN Brazil (in Portuguese). 7 December 2021. Retrieved 9 December 2021.
^ "Cuba to update domestic vaccine to battle Omicron". Al Jazeera. 2 December 2021. Retrieved 20 December 2021.
^ a b "Omicron poses very high global risk, world must prepare -WHO". Reuters. Geneva. 29 November 2021. Archived from the original on 30 November 2021. Retrieved 30 November 2021.
^ "Pfizer shot provides partial omicron shield, study finds". The Japan Times. Bloomberg. 8 December 2021. Archived from the original on 8 December 2021. Retrieved 8 December 2021.
^ "Early Lab Test Shows Omicron Weakening Vaccine Effectiveness". The Wall Street Journal. 7 December 2021. Archived from the original on 7 December 2021. Retrieved 7 December 2021.
^ "Omicron coronavirus variant partly evades Pfizer vaccine's protection, study shows". CNN. 7 December 2021. Archived from the original on 8 December 2021. Retrieved 7 December 2021.
^ "Pfizer And BioNTech Provide Update On Omicron Variant" (Press release). New York City and Mainz: Pfizer. 8 December 2021. Retrieved 8 December 2021.
^ "Coronavirus (COVID-19) booster vaccine". NHS. Government Digital Service. 17 September 2021. Retrieved 11 December 2021.
^ SARS-CoV-2 variants of concern and variants under investigation in England, technical briefing 31 (PDF) (Briefing). Public Health England. 10 December 2021. pp. 3–5, 20–22. GOV-10645. Retrieved 10 December 2021.
^ "Classification of Omicron (B.1.1.529): SARS-CoV-2 Variant of Concern". WHO. 26 November 2021. Archived from the original on 26 November 2021.
^ "Update on Omicron". World Health Organization. 28 November 2021. Archived from the original on 30 November 2021.
^ REMAP-CAP Investigators; et al. (22 April 2021). "Interleukin-6 Receptor Antagonists in Critically Ill Patients with Covid-19". New England Journal of Medicine. 384 (16): 1491–1502. doi:10.1056/NEJMoa2100433. ISSN 0028-4793. PMC 7953461. PMID 33631065. Archived from the original on 8 December 2021.
^ Kimball, Spencer (29 November 2021). "Pfizer CEO confident Covid treatment pill will be effective against omicron variant". CNBC. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ Raphael, Therese; Fazeli, Sam (1 December 2021). "Merck's Covid Drug Will Do for Now, Just in Time for Omicron". Bloomberg News. Archived from the original on 2 December 2021. Retrieved 3 December 2021.
^ Cathcart, Andrea L.; et al. (2021). "The dual function monoclonal antibodies VIR-7831 and VIR-7832 demonstrate potent in vitro and in vivo activity against SARS-CoV-2". bioRxiv 10.1101/2021.03.09.434607.
^ Cao, Yunlong; et al. (2021). "Omicron escapes the majority of existing SARS-CoV-2 neutralizing antibodies". Nature. doi:10.1038/d41586-021-03796-6.
^ Cameroni, Elisabetta; et al. (2021). "Broadly neutralizing antibodies overcome SARS-CoV-2 Omicron antigenic shift". Nature. doi:10.1038/d41586-021-03825-4. PMID 34931194.
^ Latest confirmed cases of COVID-19 in South Africa (26 November 2021) Archived 4 December 2021 at the Wayback Machine www.nicd.ac.za
^ Latest confirmed cases of COVID-19 in South Africa (3 December 2021) Archived 4 December 2021 at the Wayback Machine www.nicd.ac.za
^ see also GIS dashboard Archived 8 September 2021 at the Wayback Machine (statistical data) www.nicd.ac.za
^ "Update on Omicron". World Health Organization. 28 November 2021. Archived from the original on 30 November 2021. Retrieved 30 November 2021.
^ Pulliam, Juliet R. C.; Schalkwyk, Cari van; Govender, Nevashan; Gottberg, Anne von; Cohen, Cheryl; Groome, Michelle J.; Dushoff, Jonathan; Mlisana, Koleka; Moultrie, Harry (2 December 2021). "Increased risk of SARS-CoV-2 reinfection associated with emergence of the Omicron variant in South Africa": 2021.11.11.21266068. doi:10.1101/2021.11.11.21266068. S2CID 243983860. Archived from the original on 3 December 2021. Retrieved 3 December 2021.
^ "Omicron seems to carry higher Covid reinfection risk, says South Africa". the Guardian. 2 December 2021. Archived from the original on 3 December 2021. Retrieved 3 December 2021.
^ "'Patience is crucial': Why we won't know for weeks how dangerous Omicron is". www.science.org. Archived from the original on 30 November 2021. Retrieved 30 November 2021.
^ Network for Genomic Surveillance in South Africa (26 November 2021). "Proportion and number of clades by epiweek in South Africa, 2021" (PDF). Archived (PDF) from the original on 2 December 2021. Retrieved 2 December 2021.
^ "Risk assessment for SARS-CoV-2 variant: Omicron VOC-21NOV-01 (B.1.1.529): 3 December 2021" (PDF). GOV.UK. Archived (PDF) from the original on 4 December 2021. Retrieved 4 December 2021.
^ McCarthy K, Rachida S, Yousif M, Ndlovu N, Iwu-Jaja C, Howard W, et al. "Wastewater-based epidemiology for SARS-CoV-2 in South Africa" (PDF). National Institute for Communicable Diseases. Archived (PDF) from the original on 9 November 2021. Retrieved 30 November 2021.
^ "COVID-19: Toddlers make up 10% of hospital cases in South Africa's Omicron epicentre". gulfnews.com. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ "Prof. Albertsen deliberations". Twitter. Retrieved 11 December 2021.
^ "SARS-CoV-2 variants of concern and variants under investigation in England - Technical briefing 32" (PDF). gov.uk. UK Health Security Agency. 17 December 2021. Retrieved 19 December 2021.
^ Covid-19 Rapport om omikronvarianten [Status of the SARS-CoV-2 variant Omicron in Denmark] (PDF) (Report) (in Danish). Statens Serum Institut. 20 December 2021. Retrieved 21 December 2021.
^ Ekspertrapport den 17. december 2021 – Scenarier for smittetal og nyindlæggelser med omikronvarianten [Expert report 17 December 2021 – Scenarios for infection numbers and new hospitalizations with the Omicron-variant] (PDF) (Report) (in Danish). Statens Serum Institut. 18 December 2021. Retrieved 18 December 2021.
^ "Schweiz sitrep". Twitter. 10 December 2021. Retrieved 10 December 2021.
^ "Deutschland Omikron sitrep" (PDF).
^ "Omicron in Scotland - evidence paper". www.gov.scot. Retrieved 11 December 2021.
^ Wenseleers, Tom (22 December 2021), tomwenseleers/newcovid_belgium, retrieved 22 December 2021
^ "Ontario Dashboard". Ontario COVID-19 Science Advisory Table. Retrieved 12 December 2021.
^ "COVID Data Tracker". Centers for Disease Control and Prevention. 28 March 2020. Retrieved 21 December 2021.
^ "CDC data indicate Omicron is starting to eat into Delta's U.S. dominance". STAT. 14 December 2021. Retrieved 21 December 2021.
^ Wenseleers, Tom (20 December 2021), tomwenseleers/newcovid_belgium, retrieved 21 December 2021
^ "Presentatie Cib-RIVM: Epidemiologisch beeld" (PDF) (in Dutch).
^ "Advies VWS nav OMT 134 met aanpassing" (PDF) (in Dutch).
^ Maxmen, Amy (16 December 2021). "Omicron blindspots: why it's hard to track coronavirus variants". Nature. 600 (7890): 579. doi:10.1038/d41586-021-03698-7. PMID 34916668. S2CID 245262198.
^ "Omicron Spread in South Africa". p. 6. Archived from the original on 4 December 2021. Retrieved 4 December 2021.
^ Mandavilli, Apoorva (4 December 2021). "Omicron Variant Spreading Twice as Quickly as Delta in South Africa". The New York Times. ISSN 0362-4331. Archived from the original on 4 December 2021. Retrieved 4 December 2021.
^ The SARS-CoV-2 variant Omicron: a snapshot of where we are - 08.12.2021, 5 PM CET., retrieved 10 December 2021
^ Berger, Miriam (28 November 2021). "South Africa, which found the omicron variant first, leads Africa in coronavirus sequencing". Washington Post. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ "Sequencing by country". GISAID. 2 December 2021. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ Geddes, Linda (15 December 2021). "How big is the risk of Omicron in the UK and how do we know?". The Guardian.
^ a b Oppdatert, Publisert. "Statistikk over meldte tilfeller av virusvarianten omikron". Folkehelseinstituttet (in Norwegian). Retrieved 22 December 2021.
^ "Status på omikron-varianten (B.1.1.529) pr. 05.12.21" [Status of the Omicron variant (B.1.1.529) per 05.12.21] (in Danish). Statens Serum Institut. Retrieved 18 December 2021.
^ "Cov-Lineages". cov-lineages.org. Retrieved 20 December 2021.
^ "Tracking of Variants". GISAID. Archived from the original on 23 June 2021. Retrieved 22 December 2021. Updated frequently.
^ a b "UK Health Security Agency Omicron daily overview: 24 December 2021" (PDF).
^ "Omikron (B.1.1.529)" [Omicron (B.1.1.529)] (in Danish). Statens Serum Institut. Retrieved 21 December 2021.
^ "Tracking variants of the novel coronavirus in Canada". CTV News. 4 February 2021. Retrieved 24 December 2021.
^ "DAILY EPIDEMIOLOGICAL SUMMARY COVID-19 in Ontario: January 15, 2020 to December 22, 2021" (PDF). 19 December 2021. Table 6. Retrieved 24 December 2021.
^ a b c d "Newsnodes - Omicron tracker". newsnodes.com. Retrieved 24 December 2021.
^ a b "Wochenberichte zu COVID-19" (in German). Robert Koch Institute. 16 December 2021. Retrieved 19 December 2021.
^ a b "COVID: Germany records first death from omicron variant". DW. 23 December 2021. Retrieved 23 December 2021.
^ "Lineage B.1.1.529". cov-lineages.org. Cov-Lineages. Retrieved 19 December 2021.
^ "Omicron variant more resistant to vaccine but causes less severe covid, major South African study concludes". Washington Post. ISSN 0190-8286. Retrieved 16 December 2021. Later information provided by a Discovery Health spokeswoman put the number of total cases at 78,173, of which 19,070 tests were positive during the "omicron period" from Nov. 15 to Dec. 7.
^ "Coronavirus : chiffres clés et évolution de la COVID-19 en France et dans le Monde". www.santepubliquefrance.fr (in French). Retrieved 19 December 2021.
^ "Cases of Omicron variant in Australia and the world". COVID Live. 19 December 2021. Retrieved 19 December 2021.
^ "Tänahommikuse seisuga on haiglas 274 koroonaviirusega nakatunud patsienti" [As of this morning, the hospital has 274 patients infected with the coronavirus]. terviseamet.ee (in Estonian). 13 December 2021. Retrieved 13 December 2021. Eestis on tuvastatud kokku 26 koroonapositiivset, kelle puhul viitab genotüpiseerimine omikron tüvele, nendest kuus on kinnitatud sekveneerimise käigus... A total of 26 corona-positive cases have been identified in Estonia, in which case genotyping indicates an omicron strain, six of which have been confirmed during sequencing...
^ "Tänahommikuse seisuga on haiglas 220 koroonaviirusega nakatunud patsienti | Terviseamet". www.terviseamet.ee (in Estonian). Retrieved 22 December 2021.
^ "Tänahommikuse seisuga on haiglas 229 koroonaviirusega nakatunud patsienti | Terviseamet". www.terviseamet.ee (in Estonian). Retrieved 27 December 2021.
^ "Ómicron: the Ministry of Health confirmed the first case in Argentina". MRT. 6 December 2021. Archived from the original on 6 December 2021. Retrieved 6 December 2021.
^ "Córdoba confirmó 454 casos de la variante Ómicron de coronavirus" [Córdoba confirmed 454 cases of the Omicron variant of coronavirus] (in Spanish). Télam. 19 December 2021. Retrieved 19 December 2021.
^ "Hay más de 80 casos posibles de Ómicron en Argentina" [There are more than 80 possible cases of Ómicron in Argentina] (in Spanish). 13 December 2021. Retrieved 13 December 2021.
^ a b c d e f g h "Omicron in Europe: Where has the new COVID variant been detected?". euronews. 13 December 2021. Retrieved 20 December 2021.
^ "SARS-CoV-2-Varianten in Österreich". AGES - Österreichische Agentur für Gesundheit und Ernährungssicherheit (in German). Retrieved 20 December 2021.
^ a b "https://twitter.com/israelmoh/status/1474812592862474244". Twitter. Retrieved 26 December 2021. External link in |title= (help)
^ a b "Table 1. Confirmed cases of SARS-CoV-2 Omicron VOC reported by public sources, as of 10 December 2021 (12:00)". ecdc.europa.eu. European Centre for Disease Prevention and Control (ECDC). 10 December 2021. Retrieved 16 December 2021.
^ 김한주 (24 December 2021). "(2nd LD) New COVID-19 cases fall below 7,000 for 2nd day; critical cases hit record high". Yonhap News Agency. Retrieved 24 December 2021.
^ 이원주 (27 December 2021). "New COVID-19 cases below 5,000 for 1st time in 20 days; critical cases remain high". Yonhap News Agency. Retrieved 27 December 2021.
^ "Statistik om SARS-CoV-2 virusvarianter av särskild betydelse" [Statistics on SARS-CoV-2 virus variants of particular importance]. folkhalsomyndigheten.se. Public Health Agency of Sweden. 21 December 2021. Retrieved 21 December 2021.
^ a b c d e f g h i "Epidemiological update: Omicron variant of concern (VOC) – data as of 16 December 2021 (12:00)". European Centre for Disease Prevention and Control. 16 December 2021. Retrieved 20 December 2021.
^ "10 fresh cases take India's Omicron tally past 150-mark". The Times of India. TNN. 20 December 2021. Retrieved 20 December 2021.
^ Livemint (20 December 2021). "Omicron cases in India: States that have reported new Covid-19 variant". mint. Retrieved 20 December 2021.
^ "Delhi's LNJP Hospital reports 34 new Omicron cases". The Times of India. 21 December 2021. Retrieved 21 December 2021.
^ "オミクロン株累計200人に 国内新規感染295人―新型コロナ". Jiji (in Japanese). Retrieved 24 December 2021.
^ "Omikronvariant B.1.1.529". National Institute for Public Health and the Environment. Retrieved 15 December 2021.
^ Staines, Michael (16 December 2021). "COVID Ireland: 4,141 cases as confirmed Omicron cases reduced to 39". Newstalk. Retrieved 17 December 2021.
^ "Travel restrictions tightened as Rock confirms 24 Omicron cases". 17 December 2021. Retrieved 20 December 2021.
^ "Singapore reports 24 confirmed Omicron cases as at Thursday". www.thesundaily.my. Retrieved 18 December 2021.
^ Auto, Hermes (22 December 2021). "More Omicron cases picked up in Singapore; community spread a matter of time: MOH | The Straits Times". www.straitstimes.com. Retrieved 22 December 2021.
^ "Singapore now has at least 153 Omicron cases, including 23 local". sg.news.yahoo.com. Retrieved 25 December 2021.
^ "Kári spáir omíkron-bylgju í janúar". ruv.is (in Icelandic). 18 December 2021. Retrieved 19 December 2021.
^ "Covid-19: sulla piattaforma ICoGen 84 sequenze della variante Omicron" [Covid-19: 84 sequences of the Omicron variant on the ICoGen platform] (in Italian). 18 December 2021. Archived from the original on 20 December 2021. Retrieved 20 December 2021.
^ "ISP confirmó 30 casos de la nueva variante Ómicron a nivel nacional". CNN Chile (in Spanish). 16 December 2021. Archived from the original on 16 December 2021. Retrieved 19 December 2021.
^ "Autoridad sanitaria informa 73 casos confirmados con variante Ómicron en Chile". La Tercera. 20 December 2021. Retrieved 21 December 2021.
^ "Portugal tem 38 casos da variante ómicron. Cuidados intensivos com "tendência fortemente crescente"" [Portugal has 38 cases of the omicron variant. Intensive care shows "strongly increasing trend"]. Público. 3 December 2021. Archived from the original on 4 December 2021. Retrieved 4 December 2021.
^ "Monitorização das linhas vermelhas para a COVID-19" [Monitoring of red lines for COVID-19] (PDF). INSA (in Portuguese). National Health Service of Portugal. 3 December 2021. p. 14. Archived (PDF) from the original on 4 December 2021. Retrieved 7 December 2021.
^ "Dept warns Omicron could surge after NY". Bangkok Post. 15 December 2021. Retrieved 15 December 2021.
^ Thepgumpanat, Panarat; Tanakasempipat, Patpicha (20 December 2021). "Thailand reports first local Omicron case, eyes reinstating quarantine". The Edge Markets. Reuters. Retrieved 20 December 2021.
^ "Thailand reports first Omicron cluster, cancels some New Year events". news.trust.org. Reuters. Retrieved 24 December 2021.
^ @ThaiPBSWorld (20 December 2021). "#Thailand has confirmed 63 Omicron cases" (Tweet). Retrieved 20 December 2021 – via Twitter.
^ "Zimbabwe says country has identified 50 cases of Omicron". Reuters. Johannesburg. 3 December 2021. Archived from the original on 3 December 2021. Retrieved 3 December 2021.
^ Lucas Rocha; Giovanna Bronze; Carolina Figueiredo; Julyanne Jucáda. "Brasil tem 36 casos confirmados de Covid-19 causados pela variante Ômicron" (in Portuguese). CNN Brasil. Retrieved 20 December 2021.
^ "Suomessa on todettu yhteensä seitsemän omikronvariantin aiheuttamaa koronatartuntaa – Tiedote – THL" [A total of seven coronary infections caused by self – inflicted variants have been diagnosed in Finland – Release – THL]. Terveyden ja hyvinvoinnin laitos (in Finnish). Archived from the original on 5 December 2021. Retrieved 5 December 2021.
^ "Over 10,500 new COVID-19 cases recorded in Finland last week – News – THL". Finnish Institute for Health and Welfare (THL), Finland. Retrieved 18 December 2021. On 15 December 2021, the total number of confirmed cases of the Omicron variant in Finland was 34.
^ "Cyprus detects first cases of COVID-19 Omicron variant". news.trust.org. Reuters. Retrieved 10 December 2021.
^ "Coronavirus: 28 more people found positive for Omicron | Cyprus Mail". cyprus-mail.com. Retrieved 19 December 2021.
^ a b "Variant Omicron: 28 cas confirmés et 46 suspects (ministère)". Maghreb Arab Press (in French). Retrieved 21 December 2021.
^ @MOH_Kenya (18 December 2021). "Twenty-seven sequences (77%) were confirmed to belong to the newly identified Omicron variant of concern" (Tweet). Retrieved 20 December 2021 – via Twitter.
^ a b c d e "В России впервые с октября выявили менее 200 тыс. случаев ковида за неделю". ТАСС. Retrieved 20 December 2021.
^ "Russia confirms 41 Omicron cases, says over 70 mln vaccinated". news.trust.org. Reuters. Retrieved 22 December 2021.
^ a b "COVID-19 Update - 24 December". www.gov.ky. Retrieved 26 December 2021.
^ Ministry of Health - Uganda [@@MinofHealthUG] (18 December 2021). "PRESS RELEASE: Update on Omicron Variant in #Uganda" (Tweet). Uganda. Retrieved 19 December 2021 – via Twitter.
^ "Omicron confirmed in nine African countries, say officials". ABC News. Archived from the original on 7 December 2021. Retrieved 7 December 2021.
^ Guillén, Beatriz (3 December 2021). "México confirma el primer caso de ómicron en el país" [Mexico confirms the first omicron case in the country]. El País (in Spanish). Mexico. Retrieved 3 December 2021.
^ "MidCentral hits 90% fully vaccinated milestone; 69 community cases; 62 in hospital; 7 in ICU". Ministry of Health NZ. Retrieved 20 December 2021.
^ "Namibia detects Omicron coronavirus variant in 18 of 19 samples". Reuters. 6 December 2021. Archived from the original on 6 December 2021. Retrieved 7 December 2021.
^ "HK reports 7 imported virus cases". Hong Kong's Information Services Department (in Chinese). Retrieved 24 December 2021.
^ "Kasus Varian Omicron di RI Jadi 46". Kompas. 26 December 2021. Retrieved 26 December 2021.
^ "Senegal records first Omicron case in tourist who attended demonstration". Reuters. 5 December 2021. Archived from the original on 5 December 2021. Retrieved 5 December 2021.
^ "Omicron in southern Africa: Mozambique is worried for its economy, especially tourism". Bahrain News Agency. 10 December 2021. Retrieved 10 December 2021.
^ Newsroom. "Όμικρον: 17 κρούσματα στην Ελλάδα | Η ΚΑΘΗΜΕΡΙΝΗ". www.kathimerini.gr. Retrieved 20 December 2021.
^ Bell, Jonathan (21 December 2021). "Omicron cases surge from one to more than 100 in two weeks". www.royalgazette.com. Retrieved 24 December 2021.
^ Bell, Jonathan (24 December 2021). "Two in hospital as Bermuda passes 6,000 Covid-19 cases". www.royalgazette.com. Retrieved 26 December 2021.
^ "Latvia gets its first two Omicron cases". Public Broadcasting of Latvia. Reuters. 6 December 2021. Archived from the original on 6 December 2021. Retrieved 6 December 2021.
^ "Comunicate de presa" [Press Releases]. ms.ro (in Romanian). Ministerul Sănătăţii (Health Ministry Romania). 12 December 2021. Retrieved 13 December 2021. So far, 8 cases with the Omicron variant of the SARS-Cov-2 virus have been confirmed in Romania.
^ "MS: Încă două cazuri de infectare cu varianta Omicron au fost confirmate în România". www.digi24.ro (in Romanian). Retrieved 18 December 2021. Până în prezent, în România au fost confirmate 13 cazuri cu varianta OMICRON a virusului SARS-Cov-2.
^ "Au fost descoperite încă 9 cazuri de infectare cu varianta Omicron în România". www.digi24.ro (in Romanian). Retrieved 24 December 2021.
^ "Khairy: 62 Omicron cases detected in Malaysia so far, surge in cases possible as variant already within community". Malay Mail. 25 December 2021. Retrieved 25 December 2021.
^ "Zambia reports more Omicron variant COVID-19 cases". Xinhuanet.com. 11 December 2021. Retrieved 13 December 2021.
^ Adetifa, Dr Ifedayo (7 December 2021). "Three Additional Cases of Omicron Variant Confirmed". ncdc.gov.ng. Nigeria Centre for Disease Control (NCDC). Retrieved 11 December 2021. In addition to the three cases announced earlier on 1st December 2021, this brings the total number of confirmed cases of the Omicron variant detected in Nigeria to six (6).
^ "Koronavirus ONLINE: Válek smetl povinné očkování 60+. A 5982 případů za sobotu v ČR". Blesk.cz (in Czech). Archived from the original on 20 December 2021. Retrieved 20 December 2021.
^ "First cases of the omicron variant of coronavirus confirmed in Slovenia". GOV.SI. 14 December 2021. Retrieved 15 December 2021.
^ W3bStudio (21 December 2021). "Omicron confirmed in all Slovenian regions but one". Slovenia Times. Retrieved 22 December 2021.
^ a b "Cases of Omicron variant rise to 8 in Lebanon". www.news.cn. Retrieved 19 December 2021.
^ "Lebanon's total Omicron cases rise to 433". ANI News. Xinhua. Retrieved 26 December 2021.
^ "Covid-19 à La Réunion : identification d'un 2ème cas positif au variant « Omicron »" [Covid-19 in Reunion Island: identification of a 2nd positive case for the "Omicron" variant]. reunion.gouv.fr (in French). Les services de l'État à La Réunion. 3 December 2021. Retrieved 9 December 2021.
^ "Six cases of Omicron variant detected in Turkey – minister". Reuters. 11 December 2021. Retrieved 11 December 2021.
^ "Laboratorije Odjeljenja za molekularnu dijagnostiku potvrdile 5 slučajeva infekcije Omicron sojem". Institut za javno zdravlje Crne Gore. 16 December 2021. Retrieved 17 December 2021.
^ "Cambodia confirms 1st case of Omicron COVID-19 variant". Xinhua News Agency. 15 December 2021. Retrieved 15 December 2021.
^ "Ómicron ya está en Perú: Minsa detectó a cuatro pacientes de COVID con esta variante". gestion.pe. 19 December 2021. Retrieved 19 December 2021.
^ الأردنية (بترا), وكالة الأنباء. "الصحة تعلن عن تسجيل أول اصابتين بمتحور أوميكرون في المملكة" [The Ministry of Health announces the registration of the first two cases of the Omicron mutant in the Kingdom]. بترا -وكالة الأنباء الأردنية. Retrieved 10 December 2021.
^ الأردنية (بترا), وكالة الأنباء. "تسجيل 295 إصابة جديدة بمتحور أوميكرون في المملكة". بترا -وكالة الأنباء الأردنية. Retrieved 27 December 2021.
^ 畅, 刘 (13 December 2021). "天津从入境人员中检出奥密克戎变异株,为中国内地首次检出" [The Omicron mutant strain was detected in Tianjin from immigrants, which is the first detection in Mainland China]. The Beijing News. Retrieved 13 December 2021.
^ "Guangzhou reports China's second case of Omicron variant". South China Morning Post. 14 December 2021. Retrieved 17 December 2021.
^ "湖南长沙从入境人员中检出2例新冠病毒奥密克戎变异株感染者" [2 cases of coronavirus Omicron variant detected from incoming persons in Changsha, Hunan Province]. 18 December 2021.
^ MINSAP, Redacción (15 December 2021). "Nota informativa del Ministerio de Salud Pública". Sitio oficial de gobierno del Ministerio de Salud Pública en Cuba (in Spanish). Retrieved 20 December 2021.
^ "Malawi confirms 3 Omicron cases, issues strict traveling restrictions". www.news.cn. Retrieved 10 December 2021.
^ "First case of Omicron coronavirus variant detected in Gaza". The Times of Israel. 26 December 2021.
^ "Taiwan confirms first cases of Omicron variant". Reuters. 11 December 2021. Retrieved 11 December 2021.
^ "Taiwan reports 11 new Omicron cases - Focus Taiwan". focustaiwan.tw (in Chinese). CNA. Retrieved 26 December 2021.
^ "Lithuania confirms two Omicron infections". Lithuanian National Radio and Television. 15 December 2021. Retrieved 15 December 2021.
^ @MinSaludCol (20 December 2021). "¡ATENCIÓN! Se confirma la presencia de la variante Ómicron en Colombia" (Tweet). Retrieved 21 December 2021 – via Twitter.
^ "First Omicron cases confirmed in Slovakia". The Slovak Spectator. 11 December 2021. Retrieved 12 December 2021. First three Omicron cases have been confirmed in Slovakia.
^ Lindo, Paula (13 December 2021). "Health Ministry: Trinidad and Tobago's first omicron case breached travel protocols". Trinidad and Tobago Newsday. Retrieved 16 December 2021. TT's first recorded case of the omicron variant is an imported one.
^ "Confirman primer caso positivo de variante ómicron en Puerto Rico". CNN en Español (in Spanish). 14 December 2021. Retrieved 14 December 2021.
^ "Two confirmed cases of Omicron variant in quarantine". Fiji Broadcasting Corporation. Archived from the original on 6 December 2021. Retrieved 6 December 2021.
^ "Nepal detects first two cases of Omicron variant – health ministry". Reuters. 6 December 2021. Retrieved 6 December 2021.
^ "Philippines detects Omicron variant from 2 international travelers". GMA News. 15 December 2021. Retrieved 15 December 2021.
^ Magsambol, Bonz (20 December 2021). "Philippines detects one more case of Omicron, total now at 3". Rappler. Retrieved 22 December 2021.
^ "'Omicron variant' detected in two people in TRNC!". KIBRIS POSTASI (in Turkish). Retrieved 22 December 2021.
^ "Bangladesh reports first Omicron cases". Business Standard. 11 December 2021. Retrieved 12 December 2021.
^ "Epidemiological update: Omicron variant of concern (VOC) – data as of 8 December 2021 (12.00)". ecdc.europa.eu. ECDC. 8 December 2021. Retrieved 9 December 2021.
^ "Müller Cecília: megjött Magyarországra az omikron variáns" [Cecília Müller: the omicron variant has arrived in Hungary]. Infostart. 13 December 2021. Retrieved 13 December 2021.
^ "További 46 omikronos esetet azonosítottak". koronavirus.gov.hu (in Hungarian). 23 December 2021. Retrieved 24 December 2021.
^ "Recording the First Cases Of Omicron Variant #OmanVSCovid19". Twitter. Retrieved 14 December 2021.
^ "Coronavirus: Pakistan reports first case of Omicron variant". www.geo.tv. 9 December 2021. Retrieved 9 December 2021.
^ "Sri Lanka reports first case of Omicron variant". The Economic Times. Retrieved 3 December 2021.
^ "Georgia confirms the first two cases of Omicron coronavirus variant". Agenda.ge. Tbilisi. 20 December 2021. Retrieved 20 December 2021.
^ a b "Corona Updates: First Cases of Omicron Strain Detected in Georgia". Georgia Today. 23 December 2021. Retrieved 26 December 2021.
^ "The Kingdom of Bahrain detects a case of the Omicron variant in an incoming traveller with no local contact". Bahrain News Agency. 11 December 2021. Retrieved 13 December 2021.
^ "Ecuador confirma primer caso de Ómicron". Ministerio de Salud Pública. 14 December 2021. Retrieved 15 December 2021.
^ Coronavirus: Kuwait reports first case of Omicron variant 8 December 2021
^ "First case of Omicron detected in Maldives". ANI News. Retrieved 9 December 2021.
^ "Public Health National Emergency Operations Center, Sierra Leone". www.facebook.com. Retrieved 10 December 2021.
^ "Saudi Arabia detects first case of COVID-19 Omicron variant in Kingdom". Al Arabiya English. December 2021. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ "Tunisia records first case of omicron variant". Arab News. 3 December 2021. Archived from the original on 8 December 2021. Retrieved 5 December 2021.
^ Mukherjee, Promit; Hunnicutt, Trevor (1 December 2021). "Omicron rapidly dominating in South Africa; U.S. reports first case". Reuters. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ "Report: Iran announces 1st case of omicron variant". ABC News. The Associated Press. Archived from the original on 19 December 2021. Retrieved 19 December 2021.
^ 2443 (25 December 2021). "شناسایی ۶ بیمار جدید مبتلا به سویه اُمیکرون در کشور". ایرنا (in Persian). Retrieved 26 December 2021.
^ "В Україні виявили штам "Омікрон"" [Omicron strain found in Ukraine]. Ukrainian Ministry of Health (in Ukrainian). 18 December 2021. Archived from the original on 20 December 2021. Retrieved 20 December 2021.
^ "Panama detects first case of COVID-19 Omicron variant". Reuters. 20 December 2021. Retrieved 21 December 2021.
^ "Costa Rica Announces First Case of Omicron Variant". The Tico Times. 20 December 2021. Retrieved 21 December 2021.
^ "First Omicron cases in Aruba". The Daily Herald. Retrieved 21 December 2021.
^ "В Северной Македонии выявили первый случай заражения омикрон-штаммом". ТАСС. Retrieved 26 December 2021.
^ Vaughan, Adam (27 November 2021). "Omicron: How dangerous is the new variant first found in South Africa?". NewScientist. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ Cowan, Kyle (29 November 2021). "Inside SA leg of Omicron variant discovery: A single test result, a missing gene, and an email". News24. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ a b Whiteside, Philip (30 November 2021). "COVID-19: How the spread of Omicron went from patient zero to all around the globe". SkyNews. Archived from the original on 30 November 2021. Retrieved 1 December 2021.
^ Vliet, Kevin van (3 December 2021). "Waarom Zuid-Afrika zoveel virusvarianten ontdekt". Trouw (in Dutch). Retrieved 9 December 2021.
^ Covid: New heavily mutated variant B.1.1.529 in South Africa raises concern Archived 26 November 2021 at the Wayback Machine, 25 November 2021, BBC News, accessed 25 November 2021
^ Tracking SARS-CoV-2 variants Archived 18 June 2021 at the Wayback Machine (Tables: Currently designated Variants Under Monitoring -describes 529 variant as present in 'Multiple countries'- and 'Formerly monitored variants'- B.1.523 & B.1.619 Reclassified Nov 2021). www.who.int, accessed 25 November 2021
^ a b @BNODesk (26 November 2021). "Statement from Israel's health ministry reporting 1 confirmed case of new coronavirus variant B.1.1.529" (Tweet). Retrieved 26 November 2021 – via Twitter.
^ "מחוסנת ב-3 מנות ואישה שנסעה לאילת באוטובוס: המאומתים לזן החדשt". m.ynet.co.il (in Hebrew). 26 November 2021. Archived from the original on 27 November 2021. Retrieved 28 November 2021. "4 מאומתים לווריאנט החדש התגלו בארץ, רה"מ יקיים מסיבת עיתונאים ב-14:30" translated: "4 verified for the new variant were discovered in the country, the prime minister will hold a press conference at 14:30
^ Four cases of the new COVID-19 variant recorded in Botswana Archived 26 November 2021 at the Wayback Machine, 25 November 2021, Mmegi Online, accessed 26 November 2021
^ "Al meer dan veertig omikron-gevallen vastgesteld in Europa" [More than 40 omicron cases identified in Europe]. De Standaard (in Dutch). Belgium. 30 November 2021. Archived from the original on 30 November 2021. Retrieved 1 December 2021.
^ "Belgium detects first case of new COVID-19 variant in Europe". Reuters. 26 November 2021. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ Kesselgruber, Kerstin (27 November 2021). "Flughafen Frankfurt: Person mit Omikron-Verdacht war vollständig geimpft" [Frankfurt airport: Person suspected to be infected with Omicron Variant was fully vaccinated]. Frankfurter Rundschau (in German). Archived from the original on 27 November 2021. Retrieved 27 November 2021.
^ "UK, Germany and Italy detect Omicron coronavirus variant cases". Reuters. 27 November 2021. Archived from the original on 27 November 2021. Retrieved 27 November 2021.
^ "Coronavirus variant Omicron found in 13 positive tests so far | RIVM". www.rivm.nl. Archived from the original on 6 December 2021. Retrieved 6 December 2021.
^ "Actuele informatie over COVID-19 | RIVM" [Current information about COVID-19 | RIVM]. www.rivm.nl (in Dutch). 4 December 2021. Archived from the original on 6 April 2020. Retrieved 6 December 2021.
^ "61 travellers from South Africa in Netherlands positive for COVID-19 - authorities". Reuters. Amsterdam. 27 November 2021. Archived from the original on 26 November 2021. Retrieved 27 November 2021.
^ "Travellers test positive to Omicron COVID-19 strain after arriving in Sydney from southern Africa, NSW Health says". ABC News. 28 November 2021. Archived from the original on 28 November 2021. Retrieved 28 November 2021.
^ "To personer er indrejst i Danmark med coronavarianten Omikron" [Two people have entered Denmark with the corona variant Omicron]. www.bt.dk (in Danish). 28 November 2021. Archived from the original on 28 November 2021. Retrieved 28 November 2021.
^ Af Ritzau (28 November 2021). "Nu er det bekræftet: To personer smittet med Omikron rejst ind i Danmark" [Now it has been confirmed: Two people infected with Omicron traveled into Denmark]. ekstrabladet.dk (in Danish). Archived from the original on 28 November 2021. Retrieved 28 November 2021.
^ "Austria detects suspect Omicron case as Europe battles virus surge". WION. Archived from the original on 28 November 2021. Retrieved 28 November 2021.
^ "Omicron variant found in UK, Germany, Czech Republic". New York Post. 28 November 2021. Archived from the original on 27 November 2021. Retrieved 28 November 2021.
^ "Canada, Netherland, Australia latest countries reporting cases of omicron COVID-19 variant". ABC13. 28 November 2021. Archived from the original on 28 November 2021. Retrieved 28 November 2021.
^ Perera, Alicia (29 November 2021). "COVID-positive repatriation flight arrival to the Northern Territory tests positive to Omicron variant". ABC News. Archived from the original on 29 November 2021. Retrieved 29 November 2021.
^ Nguyen, Kevin (29 November 2021). "NSW Health confirms two more Omicron COVID-19 cases in travellers from southern Africa". ABC News. Archived from the original on 29 November 2021. Retrieved 29 November 2021.
^ "Live updates: Omicron variant". Cable News Network. 29 November 2021. Archived from the original on 30 November 2021. Retrieved 29 November 2021.
^ "Första fallet av omikron upptäckt i Sverige" [The first case of omicron detection in Sweden]. www.aftonbladet.se (in Swedish). 29 November 2021. Retrieved 29 November 2021.
^ "Spain detects first Omicron case, COVID-19 infections rise". Reuters. 29 November 2021. Archived from the original on 30 November 2021. Retrieved 30 November 2021.
^ "Omicron variant found in two previous test samples | RIVM". www.rivm.nl. Archived from the original on 4 December 2021. Retrieved 6 December 2021.
^ "NSW records fifth case of Omicron COVID-19 variant as two more potential infections investigated". ABC News. 30 November 2021. Archived from the original on 30 November 2021. Retrieved 30 November 2021.
^ "Japan's first Omicron case may help portray PM Kishida as decisive". Reuters. 30 November 2021. Archived from the original on 30 November 2021. Retrieved 30 November 2021.
^ "Two Israeli doctors test positive for Omicron COVID variant". The Jerusalem Post | JPost.com. Retrieved 30 November 2021.
^ "SP confirma terceiro caso da variante ômicron" [SP confirms third case of ômicron variant]. g1 (in Portuguese). 1 December 2021. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ "O que se sabe sobre os primeiros casos confirmados da variante Ômicron no Brasil" [What is known about the first confirmed cases of the Ômicron variant in Brazil]. CNN Brasil (in Portuguese). 30 November 2021. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ "Passa para 6 o número de casos suspeitos da variante Ômicron investigados no Brasil" [The number of suspected cases of the Ômicron variant investigated in Brazil goes to 6]. CNN Brasil (in Portuguese). 30 November 2021. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ "Germany: Leipzig reports first Omicron variant case with no travel history". Free Press Journal. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ Dahir, Abdi; Ezeamalu, Ben; Pérez-Peña, Richard (1 December 2021). "Ghana and Nigeria are the latest African countries to detect the Omicron variant". The New York Times. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ "Nigeria confirms first cases of Omicron among travellers from South Africa". Reuters. 1 December 2021. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ Graff, Amy (1 December 2021). "First case of omicron in US identified in San Francisco". San Francisco Chronicle. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ Stark, Kevin; Rodriguez, Joe Fitzgerald; Dillon, Raquel Marial (1 December 2021). "First U.S. Case of Omicron Variant Found in San Francisco Resident". San Francisco: KQED. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ O'Donnell, Dimitri (1 December 2021). "Case of Omicron variant confirmed in Ireland". RTÉ News and Current Affairs. Retrieved 12 December 2021.
^ "South Korea reports five Omicron cases on flight from Nigeria". Reuters. 1 December 2021. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ "Dutch say 14 air passengers from S. Africa with Omicron were vaccinated". Reuters. 2 December 2021. Archived from the original on 2 December 2021. Retrieved 2 December 2021.
^ "Number of confirmed omicron cases as of 3 December". Folkehelseinstituttet. 4 December 2021. Archived from the original on 4 December 2021. Retrieved 4 December 2021.
^ "France now has 25 Omicron Covid variant cases - minister". Reuters. 6 December 2021. Archived from the original on 6 December 2021. Retrieved 7 December 2021.
^ "Omicron sudah sampai ke Malaysia". Malaysiakini. 3 December 2021. Archived from the original on 3 December 2021. Retrieved 8 December 2021.
^ "Namibia detects Omicron coronavirus variant in 18 of 19 samples". Reuters. 6 December 2021. Archived from the original on 6 December 2021. Retrieved 7 December 2021.
^ "Fijians test positive for Omicron variant - Govt". RNZ. 7 December 2021. Archived from the original on 6 December 2021. Retrieved 8 December 2021.
^ "New omicron variant detected in 57 countries: WHO". www.aa.com.tr. Retrieved 8 December 2021.
^ "Africa accounts for 46% of reported cases of Omicron, WHO official says". Reuters. 9 December 2021. Retrieved 9 December 2021.
^ "Covid: First UK death recorded with Omicron variant". BBC News. 13 December 2021. Retrieved 13 December 2021.
^ "First Omicron case detected in New Zealand". Ministry of Healfh. 16 December 2021. Retrieved 16 December 2021.
^ Gregg, Aaron (26 November 2021). "Dow plunges more than 900 points as new coronavirus variant sends global markets reeling". Washington Post. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ "'Omicron' cryptocurrency soars on new variant". www.msn.com. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ "Bitcoin and other crypto plunge as fear of new COVID variant routs markets". Fortune. Archived from the original on 27 November 2021. Retrieved 27 November 2021.
^ Davies, Pascale (26 November 2021). "Bitcoin's price has slumped after a new COVID variant was found. Why?". euronews. Archived from the original on 27 November 2021. Retrieved 27 November 2021.
^ "South African markets sink on new Covid-19 variant". Moneyweb. 26 November 2021. Archived from the original on 27 November 2021. Retrieved 29 November 2021.
^ Staff Writer. "Rand tanks as UK red lists South Africa again amid new Covid variant". Archived from the original on 26 November 2021. Retrieved 29 November 2021.
^ "New variant sees Rand plummet | eNCA". www.enca.com. Archived from the original on 26 November 2021. Retrieved 29 November 2021.
^ "Omicron raises uncertainty around inflation, says Powell". BBC News. 2 December 2021. Archived from the original on 1 December 2021. Retrieved 1 December 2021.
^ "WHO cautions against imposing travel restrictions due to new variant". Reuters. Geneva. 26 November 2021. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ "Covid live updates today: Omicron variant, symptoms, vaccines efficacy, restrictions..." en.as. 28 November 2021. Archived from the original on 28 November 2021. Retrieved 28 November 2021.
^ "World closing its doors to African countries due to omicron". aa.com. 30 November 2011. Archived from the original on 30 November 2021. Retrieved 30 November 2021.
^ Yong, Clement (26 November 2021). "Singapore bans travellers from 7 African countries; no cases of new Covid-19 variant here". The Straits Times. Singapore. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ "Anvisa recomenda restrições de voo diante de nova variante de covid-19" [Anvisa recommends flight restrictions in view of the new covid-19 variant]. agenciabrasil.ebc.com.br. 26 November 2021. Archived from the original on 26 November 2021. Retrieved 27 November 2021.
^ Kennedy, Mark; Price, R. Darren. "'It's Coming': NY Declares State of Emergency Ahead of Potential Omicron Spike". NBC New York. Archived from the original on 26 November 2021. Retrieved 27 November 2021.
^ "Switzerland announces new restrictions for Israelis after the discovery of Omicron". Globally 24. Archived from the original on 27 November 2021. Retrieved 27 November 2021.
^ Winning, Alexander; Cocks, Tim (26 November 2021). "South Africa says travel bans over new variant unjustified". Reuters. Archived from the original on 26 November 2021. Retrieved 26 November 2021.
^ Zwi, Anthony. "Travel bans aren't the answer to stopping new COVID variant Omicron". The Conversation. Archived from the original on 28 November 2021. Retrieved 28 November 2021.
^ "EXCLUSIVE South Africa delays COVID vaccine deliveries as inoculations slow". Reuters. 24 November 2021. Archived from the original on 28 November 2021. Retrieved 28 November 2021.
^ Kaitlan Collins and Kate Sullivan. "Biden says new Omicron variant is 'cause for concern, not a cause for panic'". CNN. Archived from the original on 2 December 2021. Retrieved 1 December 2021.
^ "New COVID-19 restrictions in effect for parts of Canada; some productions cancelled". CTVNews. 20 December 2021. Retrieved 20 December 2021.
^ "B.C. enacts social gathering and event capacity limits as Omicron variant spreads". Global News. Retrieved 18 December 2021.
^ "B.C. limits indoor gatherings, cancels New Year's Eve events as Omicron picks up speed". CBC News. 17 December 2021. Retrieved 17 December 2021.
^ "Quebec shutting down schools, bars, gyms tonight as COVID-19 cases soar". CTV News Montreal. 20 December 2021. Retrieved 20 December 2021.
Further reading
WHO: Update on Omicron
Live Omicron Variant Location Map
Omicron variant: What have COVID vaccine makers said and are they working on new doses?
Callaway, Ewen; Ledford, Heidi (2 December 2021). "How bad is Omicron? What scientists know so far". Nature. 600 (7888): 197–199. doi:10.1038/d41586-021-03614-z. PMID 34857948. S2CID 244840636. Retrieved 3 December 2021.
External links
Corum, Jonathan; Zimmer, Carl (9 February 2021). "Coronavirus Variant Tracker". The New York Times. Archived from the original on 30 November 2021. Retrieved 1 December 2021. Constantly Updated
Archived video:
Mohale F, Phaahla J, Oliveira T, Lessels R, Gottberg A, Moore P, Crisp N (25 November 2021). Health Department briefs media about a new so-called super-variant (Internet video live stream). South Africa: eNCA. Retrieved 27 November 2021. Archived at the Wayback Machine and Ghostarchive.
Oliveira T, Kamwendo S (26 November 2021). Professor Tulio de Oliviera on the new COVID-19 variant (Internet video live stream). South Africa: SABC News. Archived from the original on 29 November 2021. Retrieved 27 November 2021. Archived at the Wayback Machine and Ghostarchive