About Omicron, the National Health Commission authority to answer!


For the Novel Coronavirus omicron variant, the NHC has organized experts from the China Center for Disease Control and Prevention to answer relevant questions: 1.Discovery and prevalence of the Omicron variant On 9 November 2021, a Novel Coronavirus.1.1.529 variant was detected for the first time from case samples in South Africa.In just two weeks, the mutant strain has become the absolute dominant strain in the number of COVID-19 cases in Gauteng Province, South Africa, with rapid growth.On November 26, WHO identified it as the fifth “Variant of Concern” (VOC), named Omicron.As of 28 November, imports of this variant have been detected in South Africa, Israel, Belgium, Italy, the United Kingdom, Austria and Hong Kong, China.No importation of the mutant has been found in other provinces and cities in China.The omicron variant strain was first discovered and reported in South Africa, but it does not mean that the virus evolved in South Africa, and the discovery place of the variant strain is not necessarily the origin.According to the information currently shared by the Novel Coronavirus database GISAID, the number of mutation sites of the Novel Coronavirus Omicron variant is significantly higher than that of all novel Coronavirus variants circulating in the last 2 years, especially in the Spike protein.It is speculated that the reasons for its occurrence may be as follows :(1) after the infection of novel coronavirus in immunodeficient patients, a large number of mutations have accumulated over a long period of evolution in the body, which are transmitted by chance;(2) Novel coronavirus infection in an animal population, in which the adaptive evolution of the virus occurs in the process of animal population transmission, the mutation rate is higher than that of humans, and then the virus spills out and spreads to humans;(3) This variant strain has been circulating for a long time in countries or regions with poor monitoring of novel coronavirus genome variation. Due to inadequate monitoring capacity, the intermediate generation virus of its evolution has not been detected in time.3. Transmissibility of omicron variant Strains At present, there are no systematic data on transmissibility, virulence and immune escape of omicron variant strains worldwide.However, omicronon mutant strains also had important amino acid mutation sites of Alpha (Alpha), Beta (Beta), Gamma (Gamma) and Delta (Delta) spike proteins of the first four VOC variants, including mutation sites that enhanced cell receptor affinity and viral replication.Epidemiological and laboratory surveillance data indicate a significant increase in the number of cases infected with the Omicron variant in South Africa, which has partially replaced the Delta variant, and the transmisciability of the omicron variant needs to be further monitored.4. Studies on the effect of Omicron mutant strains on vaccine and antibody drugs showed that the mutation of Novel coronavirusS protein K417N, E484A or N501Y suggested enhanced immune escape ability;The omicron mutant also had a triple mutation of K417N+E484A+N501Y.In addition, omicron variant strains also have several other mutations that may reduce the neutralization activity of some monoclonal antibodies.The superposition of mutations may reduce the protective efficacy of some antibody drugs against omicron mutant strains, and the ability of immune escape against existing vaccines needs further monitoring and research.5. Whether ormicron mutant strains affect nucleic acid detection reagents currently used in China Genomic analysis of ormicron mutant strains showed that the mutation site did not affect the sensitivity and specificity of the mainstream nucleic acid detection reagents in China.The mutation loci of the omicron variant strain were mainly concentrated in the high variation region of S protein gene, not located in the target region of nucleic acid detection reagent and probe published in the eighth edition of COVID-19 Prevention and Control Protocol (ORF1ab gene and N gene published to the world by the Institute of Viral Disease, China CDC).However, data from several laboratories in South Africa suggest that nucleic acid detection reagents targeting THE S gene may not be effective in detecting the S gene of the omicron variant.6. Measures taken by Relevant Countries and regions In view of the rapid prevalence of the omikron variant in South Africa, a number of countries and regions, including the United States, the United Kingdom, the European Union, Russia, Israel, Taiwan and Hong Kong, have imposed restrictions on the entry of travelers from southern Africa.7. Countermeasures In China The prevention and control strategy of “prevent importation from abroad, prevent rebound from within” is still effective for omicron mutant strains.The National Institute of Viral Disease, China CDC has established a specific nucleic acid test for the omicron variant strain, and continues to conduct genome surveillance for possible imported cases.These measures will facilitate the timely detection of omicron variants that may be imported into China.WHO recommends that countries strengthen surveillance, reporting and research on the Novel Coronavirus, and take effective public health measures to stop transmission of the virus;Effective measures that individuals are advised to take to prevent infection include staying at least 1 meter away in public places, wearing a mask, opening Windows for ventilation, keeping hands clean, coughing or sneezing into elbows or tissues, getting vaccinated, and avoiding poorly ventilated or crowded places.It is unclear whether the omicron variant is more transmissible, pathogenic and immune escape than other VOC variants, with preliminary results expected in the coming weeks.But it is now known that all variants can cause severe illness or death, so preventing transmission is always key and COVID-19 vaccines remain effective in reducing severe illness and death.9. In the face of the new Novel Coronavirus omicron variant, what should the public pay attention to in their daily life and work?(1) Wearing masks is still an effective way to block the spread of the virus, and it is also suitable for omicron variant strains.Wearing a mask in indoor public places and on public transport is also necessary even after full vaccination and booster shots have been completed.In addition, wash your hands frequently and do a good job of indoor ventilation.(2) Do a good job in personal health monitoring.Monitor your body temperature and seek medical advice when you have suspected COVID-19 symptoms, such as fever, cough and shortness of breath.(3) Reduce non-essential entry and exit.In just a few days, many countries and regions have reported the importation of omicron mutant strain, and China is also facing the risk of importation of the mutant strain, and the global understanding of the mutant strain is still limited.Therefore, travel to high-risk areas should be minimized and personal protection during travel should be enhanced to reduce the chance of infection with the Omicron variant strain.

Leave a Reply

Your email address will not be published.