The domestic epidemic situation is sporadic at many points and the number of asymptomatic infected people is increasing Experts: Epidemic prevention needs three lines of defense to play a coordinated role

On March 9, 31 provinces (autonomous regions and municipalities directly under the Central Government) and the Xinjiang Production and Construction Corps reported 402 new locally confirmed cases and 435 cases of local asymptomatic infection. The national epidemic situation shows a multi-point sporadic trend, and there is a new feature in this round of epidemics, that is, since the 6th, the number of new cases of asymptomatic infected people in the mainland for four consecutive days has been higher than the number of new local cases. Relevant experts told the Global Times reporter that there are three lines of defense for epidemic prevention at present, the first of which is physical barriers, including traffic restrictions, isolation and wearing masks. The second line of defense is vaccines, the third line of defense is medical treatment, none of the three lines can be relaxed, and they cannot be replaced by each other, but can only play a coordinated role.

Comprehensive analysis of the 9th data shows that the local confirmed cases in Jilin are the most, with a total of 165 cases, followed by 66 cases in Shandong and Gansu, 21 cases in Shaanxi, 19 cases in Tianjin, 17 cases in Guangdong, 13 cases in Jiangsu, 10 cases in Hebei, 4 cases each in Beijing, Liaoning and Shanghai, 3 cases each in Inner Mongolia, Zhejiang and Yunnan, and 2 cases each in Shanxi and Henan. In addition, among the 435 cases of local asymptomatic infection, Jilin accounted for 179 cases, followed by 112 cases in Shandong and 76 cases in Shanghai, and other local asymptomatic infected people were distributed in Yunnan, Gansu, Heilongjiang, Hebei, Jiangsu, Guangdong, Tianjin, Liaoning, Anhui, Henan, Beijing, Guangxi, Qinghai and other places. A total of 20 provinces (autonomous regions and municipalities directly under the Central Government) have found indigenous confirmed cases and asymptomatic infected people, and there is a multi-point sporadic trend.

Among them, the asymptomatic infected people in Shanghai are 19 times that of confirmed cases, Yunnan is 7 times, Shandong is 2 times, and the asymptomatic infected people in Jilin and other places are also higher than the confirmed cases. Data from the Qingdao epidemic prevention and control press conference on the 9th showed that "since the outbreak of the epidemic in Laixi on March 4, as of 12:00 on March 9, Laixi City has reported a total of 233 confirmed cases and 344 asymptomatic infected people." ”

According to the data released on the official website of the National Health Commission, a total of 233 new local cases and 322 cases of local asymptomatic infected people were reported nationwide on the 8th. On the 7th, a total of 175 new indigenous cases and 330 cases of local asymptomatic infection were reported nationwide. On the 6th, a total of 214 new indigenous cases and 312 local asymptomatic infected people were reported nationwide. The data shows that the number of asymptomatic infected people in the mainland for 4 consecutive days exceeds the number of new local confirmed cases.

Lu Jiahai, director of the Key Laboratory of Quality Monitoring and Evaluation of Vaccines and Biological Products of the State Drug Administration and professor of the School of Public Health of Sun Yat-sen University, believes that the epidemic situation is complex, there is hidden transmission, and it is sporadic. Because the Aomikron strain causes more asymptomatic infections, the infection is mainly mild, resulting in the outbreak of the epidemic hidden for a period of time before the outbreak.

On the 9th, Jiang Fachun, deputy director of the Qingdao Municipal Center for Disease Control and Prevention, said that the epidemic has been confirmed to be a variant of Aomi Kerong: "The transmission speed of the Aomi Kerong mutation is faster, and it is easier to cause individual infection and transmission between people. Second, the symptoms of infection with the Omikejong variant will appear milder than other variants, and these symptoms are similar to the symptoms of respiratory infectious diseases such as influenza, especially in the early stages, when the general diagnosis is more difficult to identify, so more punctate sporadic or even local outbreaks are more likely to appear. Wang Huaqing, chief expert of the immunization program of the Chinese Center for Disease Control and Prevention, once said that the World Health Organization also has relevant statistics, during the epidemic of Theomilon strain, the highest reported incidence in the world in a week was close to 24 million, which was 4 times the peak of the previous epidemic of other variant strains. So it is very contagious.

An anonymous immunology expert added another point of view to the Global Times reporter: at present, there are more infected people in the mainland and the distribution area is wide, and there are more sources, which will also increase the possibility of infection. In addition, one study showed that infected people with the Omikejong BA.2 variant were more difficult to detect and had an increased chance of missing tests. According to the news released at the press conference on the prevention and control of the new crown epidemic in Beijing on the 9th, Beijing sequenced the whole genome of the sample of infected person 2 notified on March 8, and the results showed that the virus belonged to the Omiljung variant (BA.2 evolutionary branch)

Yang Zhanqiu, a professor at the Institute of Virology of the Medical College of Wuhan University, told the Global Times that the multi-point distribution of this round of epidemics across the country is related to the characteristics of the Omikerong variant. "This variant is characterized by a short incubation period of post-infection onset, an average of 2-3 days, and it is easy to develop rapidly, so it is more likely to spread rapidly between family members and in cluster activities." Asymptomatic infected people are also invisible infection, the increase in the number is a normal phenomenon, which indicates that the virus is not pathogenic, because the incubation period is short, 2-3 days is the acute detoxification period, so it is easy to find asymptomatic in the early stage. Yang Zhanqiu believes that the current prevention and control measures in the mainland, such as accelerating the organization of nucleic acid screening in key areas and strengthening the investigation of circulation investigation, are still effective in dealing with the Aomi Kerong variant.

Vaccines are still the main solution for how to prevent the cunning Olmikron. Wang Huaqing said that in January the World Health Organization once again stressed that our existing COVID-19 vaccine focuses on reducing severe illness and death, as well as protecting the health system. Jiang Fachun also proposed to actively vaccinate and complete the whole process of vaccination in a timely manner.

According to the website data of the National Health commission, on March 8, 31 provinces (autonomous regions and municipalities directly under the central government) and the Xinjiang Production and Construction Corps reported a cumulative total of 3,169,916,000 doses of the new crown virus vaccine.

Feng Duojia, president of the China Vaccine Industry Association, told the Global Times reporter that at present, the mainland vaccination has covered about 83% of the population, from the infection of more asymptomatic or lighter onset, the vaccine has played an important role, the initial immune barrier should have been established. However, global vaccination only covers 40% of the population, and the distribution is very unbalanced, so the epidemic has not disappeared, and globally, the mutation rate of the virus is faster than the speed of immune barrier construction, "so experts estimate that the future immunization strategy is first of all to continue to accelerate the vaccine immunization of the global population and build the global barrier as soon as possible; the second is to continue to strengthen immunity to high-risk positions and high-risk groups for virus mutation; the third is to continue to closely observe the dynamics of the epidemic and the immune effect. Research and develop strategies for a second round of vaccination if necessary. Feng Duojia said, "I think there are three lines of defense against epidemics, the first of which is physical barriers, including traffic restrictions, isolation and wearing masks." The second line of defense is vaccines, and the third line of defense is medical treatment. The three lines have their own advantages, but also have their own shortcomings, can not replace each other, can only play a synergistic role, now in the case of the epidemic which line can not be relaxed, if the first line is relaxed, the second line is not enough to resist the mutation and spread of the virus, the third line will be more precarious. ”