In the past three months, our country has monitored the import of more than 130 sub-branches of and Omicron into our country, including BQ.1 and XBB. Will it trigger a new round of epidemic in the country? Is it possible that new coronavirus strains will change more in the future? Xu Wenbo, director of the Institute of Virology of the Chinese Center for Disease Control and Prevention, will give you the answer.
BQ.1 and XBB branches have been discovered in many places
As BQ.1 and XBB have increased transmissibility and immune evasion capabilities, they have gradually become dominant strains in other countries. So, how do they perform in our country? The current monitoring results of
show that more than 130 sub-branches of including BQ.1 and XBB are imported into our country's . Among them, 50 subclades have caused associated local cases or outbreaks. BQ.1 and its sub-branch have been detected in 49 cases in 9 provinces, and and have been detected in 11 cases in 3 provinces.
State Council Joint Prevention and Control Mechanism Press Conference Video Screenshot
"BQ.1 and XBB have not yet formed a dominant spread in our country." Xu Wenbo introduced that the viruses currently spreading in our country are still mainly BA.5.2 and BF.7. "But its propagation advantage will gradually increase." Xu Wenbo further introduced that monitoring analysis believes that BQ.1, XBB and BA.5.2, BF.7 and more than 50 other input sub-branches may form a co-circulation with . How pathogenic is the new variant strain of
?
"In countries where BQ.1 and XBB are prevalent, their severe disease and mortality rates have not increased significantly. " Xu Wenbo said that at present, it seems that the new mainstream variant strain is not significantly different from other series of Omicron variant strains in terms of its pathogenicity.
In terms of preventing BQ.1 and XBB, Xu Wenbo believes that, just like preventing other Omicron variants, everyone must be the first person responsible for their own health.
In order to monitor whether the pathogenicity of the new mutant strain has changed, research institutions will combine monitoring of the genomic variation and clinical characteristics of the new mutant strain. Xu Wenbo said that if there are any changes in the clinical characteristics of the virus after infection, it will be linked to the genomic characteristics for study and judgment. However, there have been no reports of increased severe illness and death caused by BQ.1 and XBB at home and abroad. Will the new variant
cause reinfection?
"Now we are infected with BF.7 and BA.5.2. If new mutant strains appear, there is still a risk of reinfection." Wang Guiqiang, director of the Department of Infectious Diseases at Peking University First Hospital, said frankly that after recovery from infection, reinfection with the new coronavirus after a period of time is often caused by the mutation of the new coronavirus. Wang Guiqiang introduced the possibility of reinfection and the interval between reinfections one by one. He said that from the current data, the risk of reinfection of Omicron strain is higher than that of previous strains , such as delta and the original strain. Generally, there will be a gap period before the secondary infection of and the emergence of , and it will not be reinfected soon after the infection.
Press Conference of the Joint Prevention and Control Mechanism of the State Council Video screenshot
"The time interval between breakthrough reinfection and clinical manifestations are closely related." Wang Guiqiang said that the shorter the interval, the milder the symptoms, and the longer the interval, the more severe the symptoms will be, which is directly related to the antibody immunity in the body. A Swedish study found that secondary or third infections with different strains of Omicron had milder symptoms, and they were basically asymptomatic infections or mild cases.
Wang Guiqiang also emphasized that the elderly should avoid reinfection. Studies have shown that if the elderly are reinfected, some patients will suffer from severe illness or even die. Therefore, it is necessary to fully realize that vaccination can reduce the occurrence and severity of secondary infections, and it is again recommended that the elderly and people with underlying diseases get vaccinated as soon as possible.
Will there be a new coronavirus strain with high transmissibility and fatality rate
in the future?
Xu Wenbo introduced that during the widespread epidemic of Omicron mutant strains in the population, they will continue to produce more progeny series sub-branches through genetic variation and recombination between Omicron mutant strains, but the new strain of is less likely to cause a significant increase in pathogenicity .
The risk of hospitalization, severe illness and death caused by the Omicron variant is lower than that of previous variants such as Delta. There is no significant difference in the severe illness and mortality rates caused by infections from different branches of Omicron. The current more than 700 branches of have not seen a significant increase in the severe disease rate or fatality rate, and the majority are mild and asymptomatic.
Regarding whether strains with high contagiousness and fatality rates will emerge, this is not only related to the pathogenicity and transmissibility of the virus itself, but also to the immunity status of the population. During the global epidemic of the new coronavirus, the population has established a certain degree of herd immunity through natural infection and vaccination, and the possibility of the emergence of strains that are both highly contagious and highly lethal is low .
What are the methods for monitoring prevalent mutant strains in China?
After the national new coronavirus epidemic prevention and control strategy was optimized, the Institute of Virology of the Chinese Center for Disease Control and Prevention developed the "my country Population New Coronavirus Variant Strain Surveillance Work Plan" based on the reality that multiple new coronavirus subtypes are co-circulating in my country. The
plan requires each province to select three cities, and each city to select a sentinel hospital. Each sentinel hospital will collect specimens from 15 outpatient emergency cases, 10 severe cases, and all death cases every week for viral genome sequence determination and analysis, and within a week, the sequencing data will be uploaded to the Virus Disease Center of the China Centers for Disease Control and Prevention, and will establish a national new coronavirus genome database .
Through the implementation of the plan, it can real-time monitor the epidemic dynamics of the new coronavirus Omicron series mutant strains in China and the proportion of each subtype, and provide timely early warning of new mutant strains with potential changes in biological characteristics in terms of immune escape, transmissibility, and pathogenicity, etc., and provide scientific basic data for nucleic acid antigen reagent evaluation, vaccine development, and epidemic prevention and control.
Source: Xiaokang Toutiao comprehensive CCTV news, National Health Commission official website, Science and Technology Daily, The Paper
Editor: Tianyuan Chuying
Proofreading: Zhou Jingtao
Review: Wang Fang
Click to enter China Xiaokang.com!
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-