Novel coronavirus pneumonia was reported novel coronavirus pneumonia in Tianjin in January 12, 2022. A total of 137 patients were diagnosed as positive new crown pneumonia virus in Tianjin, including 76 cases (50 cases of mild pneumonia, 26 cases of common type) and 14 cases of asymptomatic infection of local COVID-19 in January 12th. The other 44 cases of positive infection were reported after further verification by the clinical expert group. It is worth mentioning that Han Jinyan, director of the Tianjin Center for Disease Control and prevention, said at the press conference that in the analysis of the existing reports, 103 cases had completed the whole vaccination of COVID-19 vaccine (including 32 cases of enhanced vaccination), and 3 cases had only 1 doses of inactivated vaccine in 107 cases, and only 1 cases did not receive vaccination. Before that, Tianjin also mentioned in the official bulletin of January 11th that according to the epidemiological data analysis of 80 cases of COVID-19 infection at that time, only 1 children were not vaccinated with new crown vaccine, 3 of them were inoculated with 1 doses of inactivated COVID-19 vaccine, and 76 cases were vaccinated in the whole process, among which 20 cases were strengthened. In addition, according to the track of confirmed cases in Yuzhou, Henan, most of the confirmed cases have been vaccinated with two doses of COVID-19 vaccine, and some cases have been vaccinated. In view of the breakthrough infection (that is, the test results of COVID-19 positive after inoculation for more than 14 days after completion of vaccination), virologist Chang Rongshan told the interface news that after the human body was vaccinated, the humoral immunity and the concentration of the comprehensive antibodies would decrease with time and gradually lose the protection of antibodies. "Therefore, in this case, if the immunization is not strengthened or re immunized in time, the human body will lose the antibody in the face of the Omicron strain with upgraded transmission. This explains why only one of the more than 100 infected people is not vaccinated in a scientific sense, which is not the problem of the vaccine itself." Chang Rongshan said. "At present, it is in the high incidence season of winter epidemics. According to the situation announced in Tianjin, first, children are less vaccinated. Secondly, those who have been vaccinated may be more than 4-6 months. Because the vaccination time is too long, they are easy to be infected without booster injection or re immunization." Chang Rongshan said that foreign research data showed that after 90 days of vaccination with two doses of vaccine (mrna-1273), the effective rate against Omicron decreased from an average of 30.4% to 15.2%; After 270 days, its effectiveness against Omicron decreased to 0. Chang Rong Shan further indicated that even with rabies vaccine and hepatitis B vaccine, the current vaccine protection rate can not reach 100%, and the COVID-19 vaccine is not an ideal vaccine. "Many people are skeptical about the role of the vaccine, but in fact, the COVID-19 vaccine is an emergency vaccine. The globally recognized rate of 50% can be approved for use. Compared with influenza vaccine, after more than a decade of vaccination, influenza prevention needs people to receive seeds every year, and its efficiency is only between 40%-60%". For Omicron prevention and control, how effective can vaccination play? Zhang Wenhong, director of novel coronavirus pneumonia in Hongkong, cited the findings of the team in Hongkong and the international team. The results showed that the two strains of vaccine inoculated by the two strains of vaccine were difficult to prevent. The third needle inoculation could significantly reduce the incidence of the symptoms of new crown pneumonia, and could help control the occurrence of hospitalized cases and deaths. In addition, the research team of the national infectious diseases Medical Center also showed that the antibody produced by the third injection of the vaccine can neutralize the Omicron and delta strains, which has the potential to reduce the occurrence of severe cases. Relevant papers published in cell research show that on the basis of two doses of inactivated vaccine, the third dose of homologous and heterologous enhancement has increased the neutralization ability of human body to Omicron strain by 8.07 times and 15.87 times respectively. It is worth mentioning that in Britain, where the number of infected people has increased sharply, Omicron has not caused an increase in severe illness rate and mortality. Zhang Wenhong said publicly, "the reason is that the vaccination rate of the new crown vaccine in the UK has reached 80%, the vaccination rate of three shots has exceeded 50%, and there has not been a serious run on medical resources". Previously, there were cases of imported Omicron in Zhejiang. Sheng Jifang, director of the Department of infectious diseases of the First Affiliated Hospital of the Medical College of Zhejiang University, said in an interview that from these cases, the symptoms of the patients were relatively mild, mainly manifested in upper respiratory tract problems, including cough, pharyngeal pain, fever, olfactory failure, etc. Novel coronavirus pneumonia is a common disease. Most of these patients come back from abroad, are relatively young, and have been vaccinated, so they are all mild. This is another point of view. Vaccination is very effective in preventing new crown pneumonia, whether it is a delta variant or an Olympic drug. For the effect of vaccination on the prevention of severe illness and death, Chang Rongshan affirmed, "regardless of any vaccine, research has proved that it is very good in the prevention of severe illness and death. Taking Britain and the United States as an example, although the medical treatment rate is rising, the occupancy rate of ICU is not higher than that in the same period last year, down to one sixth of that in the same period last year, which shows that the severe illness rate has decreased very much." On December 23, 2021, the national infectious diseases Medical Center (Huashan Hospital Affiliated to Fudan University) officially published the results of China's first peer-reviewed immune evaluation of intensified vaccination against Omicron strain on emerging microbes infections. The study shows that strengthening public health and social measures (phsm) and the third vaccination are the best strategies to form a population epidemic prevention barrier against Omicron mutant in the world. If the virus further mutates in the follow-up, it is not ruled out that it may enter the prevention and control strategy similar to influenza virus vaccination, so as to deal with the variation of the virus by increasing the frequency of vaccination. "Judging from the current situation, only by vaccination, booster injection or re immunization, that is, the so-called fourth injection, can we form an immune barrier to protect ourselves. Especially for densely populated big cities, it is very necessary." Chang Rongshan said to the interface news. (Xinhua News Agency)