The possibility of Omicron mutating into a highly pathogenic strain is small Vaccination is the best way to obtain antibodies

At present, the top priority of the prevention and control of the new crown epidemic is still to ensure the medical treatment of the masses. Yesterday, at the press conference of the Joint Prevention and Control Mechanism of the State Council, experts said that it is less likely that the Omicron strain will mutate into a highly infectious and highly pathogenic strain, and people of all ages can be vaccinated against the new crown vaccine. Effectively reduce the risk of severe disease and death.

Real-time monitoring of the prevalence of Omicron mutant strains

As of December 18, 709 subclades have evolved from five clades including BA.1 to BA.5 in the world. Xu Wenbo, director of the Institute of Viral Diseases of the Chinese Center for Disease Control and Prevention, introduced at the press conference that the mutation of Omicron will continue, and the current trend of mutation is that strains with strong immune escape ability are dominant. Immune escape makes the population more susceptible to the strain, even if the virus’s transmissibility does not increase, the transmission advantage will still increase. “However, it is less likely that the virus will mutate into a strain with enhanced transmissibility and increased pathogenicity.” Xu Wenbo said that the hospitalization, severe illness, and death cases caused by the Omicron mutant strain were significantly lower than those of the early Delta strain and the other variants. In addition, the current population has obtained a certain degree of immunity through vaccination or natural infection, which has better protection for the population.

After the optimization of the new crown epidemic prevention and control policy, the Institute of Virology of the Chinese Center for Disease Control and Prevention formulated the “Working Plan for Surveillance of New Coronavirus Variant Strains in my country’s Population” based on the reality that multiple new coronavirus subtypes are co-circulating in my country. Through the implementation of this plan, it is possible to monitor in real time the dynamics of the prevalence of the new coronavirus Omicron series variants in my country, the composition ratio of each subtype, and new variants with potential changes in biological characteristics.

People who have been infected still need to take personal protection

“Although Omicron infection is mostly self-limiting, with relatively low pathogenicity or severity, we do not advocate or recommend deliberate infection.” Wang Guiqiang, director of the Department of Infectious Diseases, Peking University First Hospital, said that after infection, , Some patients have clinical symptoms, including fever, muscle and joint pain, sore throat, etc., which seriously affect the quality of life and normal work. In addition, once a large number of patients appear in a short period of time, it will seriously affect social order; at the same time, it will also cause huge pressure or even a run on medical institutions, affecting the daily treatment of critically ill patients by medical institutions. He specifically reminded that those with underlying diseases, especially the elderly who have not been vaccinated, must take good protection and not be infected at the peak of the first round of epidemics.

Wang Guiqiang analyzed that as time goes by, the rapid rise of the first round of the epidemic will slow down. After a period of time, with large-scale social activities, there may be a new round of epidemics. The emergence of waves in the epidemic may eventually form a certain herd immunity barrier, and the incidence rate will drop significantly. After being infected with BF.7, BA.5.2, if a new mutant strain appears, people still have the risk of re-infection. Judging from the current data, the risk of reinfection with the Omicron strain is higher than that of the Delta strain and the original strain. He reminded that people who have been infected with Omicron should still take personal protection after the emergence of new viral strains.

Young people are also at risk of severe disease from Omicron infection

It is said that there are more asymptomatic infections after infection with the Omicron strain, and the antibody obtained from infection is worse than vaccination to prevent re-infection, so vaccination is not as good as infection with the virus. In this regard, Wang Huaqing, chief expert of the immunization program of the Chinese Center for Disease Control and Prevention, responded that although the pathogenicity of the currently popular Omicron strain has weakened, there is still a risk of severe illness and death after infection, and this risk is common in all age groups. All are reflected.

Regarding whether the new coronavirus vaccine is only valid for 6 months, Wang Huaqing said that after vaccination, it will play a protective role through the production of antibodies and cellular immunity. Antibody levels decline over time. In addition, as the virus mutates, immune escape is increasing, further weakening the effect of antibodies. However, the role of cellular immunity in preventing severe illness and death is relatively long-lasting. Studies have shown that booster injections can further arouse the body’s immune memory cells and increase antibody levels. He said that the follow-up will systematically evaluate the effect of enhanced immunization and continuously improve the immunization strategy.

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What is the criterion for judging the death caused by the new crown?

Wang Guiqiang: Pneumonia and respiratory failure caused by the new crown virus are the primary death diagnoses, which are classified as deaths caused by the new crown virus infection; deaths caused by other diseases and underlying diseases are not classified as deaths caused by the new crown virus. In order to better standardize the determination of death caused by the new crown epidemic, my country currently requires consultation and discussion of death cases to finally determine whether the patient died of the new crown or other underlying diseases.