注意！新冠病毒新变体，奥密克戎(Omicron )

Fact sheet: The Technical Advisory Group on SARS-CoV-2 Virus Evolution (TAG-VE) is an independent expert group that regularly monitors and evaluates the evolution of the SARS-CoV-2 virus and assesses whether specific mutations and combinations of mutations change the behavior of the virus. TAG-VE met on November 26, 2021 to evaluate the SARS-CoV-2 virus variant: B.1.1.529.

This variant has a large number of mutations, some of which are concerning. Preliminary evidence suggests this variant carries an increased risk of reinfection compared with other VOCs (variants of concern). The number of cases infected with this variant appears to be increasing in almost all provinces in South Africa. Current SARS-CoV-2 PCR diagnostics still detect this variant. Some laboratories have shown that in a widely used PCR test, one of the three target genes is not detected (called S gene loss or S gene target failure), so the test can serve as a marker for this variant (pending sequencing confirmation). Using this approach, the variant was discovered faster than previous surges in infections, suggesting the B.1.1.529 variant may have a growth advantage.

Currently, there are extensive studies underway and TAG-VE will continue to evaluate the B.1.1.529 variant. The WHO will also communicate new findings with member states and the public as needed.

Based on evidence demonstrating harmful changes in the epidemiology of COVID-19, TAG-VE recommends that the World Health Organization designate the B.1.1.529 variant as a VOC, and the World Health Organization designates B.1.1.529 as a VOC and names it Omicron.

Therefore, countries are asked to take the following actions:

Increase surveillance and sequencing efforts to better understand circulating SARS-CoV-2 variants.

Submit the complete genome sequence and associated $data to publicly available databases such as GISAID.

Report initial cases/clusters related to VOC infections to the World Health Organization through the International Health Regulations mechanism.

Where possible and in coordination with the international community, conduct field investigations and laboratory assessments to further understand the potential impact of this VOC on COVID-19 epidemiology, severity, effectiveness of public health and social measures, diagnostic methods, immune responses, antibody neutralization, or other relevant characteristics.

Individuals are reminded to take steps to reduce their risk of contracting COVID-19, including proven public health and social measures such as wearing a well-fitting mask, practicing hand hygiene, maintaining physical distance, improving ventilation of indoor spaces, avoiding crowded spaces, and getting vaccinated against COVID-19.

For reference, the World Health Organization has designated working definitions for SARS-CoV-2 variants of observation (VOI) and variants of concern (VOC).

SARS-CoV-2 VOIs are SARS-CoV-2 variants:

Have genetic changes that are predicted or known to affect viral properties (such as infectivity, disease severity, immune escape, diagnostic or treatment escape); and, COVID-19 is circulating globally, with increasing relative prevalence and case numbers over time in multiple countries, or other clear epidemiological impacts indicating new risks to global public health.

SARS-CoV-2 VOCs are SARS-CoV-2 variants that meet the definition of VOI (see above) and have been shown, through comparative assessment, to be associated with one or more of the following changes of global public health significance:

Increased contagiousness or harmful changes in the epidemiology of COVID-19; or

Increased toxicity or changes in clinical disease manifestations; or

Reduced effectiveness of public health and social measures or available diagnostic tools, COVID-19 vaccines, treatments.

References:

https://www.who.int/news/item/26-11-2021-classification-of-omicron-(b.1.1.529)-sars-cov-2-variant-of-concern