China Youth Daily client, Shanghai, March 16 (China Youth Daily, China Youth Daily reporter Wei Qimeng) The reporter just learned from the press conference on Shanghai’s epidemic prevention and control work that 1 new case of new coronary pneumonia has been diagnosed locally in the city. Cases (mild) were recovered from asymptomatic infections; 19 new local asymptomatic infections were found, 7 cases were found in centralized isolation control, 1 case was found in the co-investigation of people returning to Shanghai from other provinces, and the rest were screened by relevant risk groups Discover.
Starting today, Shanghai has conducted a new round of nucleic acid screening for populations in key areas in a grid-based manner. Zhao Dandan, deputy director of the Health Committee of the Shanghai Municipal Health Bureau, explained that this is to detect potential sources of infection as soon as possible, cut off the route of transmission, and achieve social dynamic clearance as soon as possible. He said that after research and judgment by the expert group, some key areas were identified based on regional risks and other conditions. Within 48 hours today and tomorrow, people in these key areas will be screened twice for nucleic acid. There are already high-risk positions in closed-loop management and personnel who are already in the routine screening work mechanism, and continue to carry out routine screening according to the original mechanism. Nucleic acid screening in key areas does not take “2+12” measures, and all districts should follow the city’s unified deployment and must not increase the number without authorization.
Wu Jinglei, director of the Shanghai Municipal Health Commission, answered the media, “Why should asymptomatic patients be subject to centralized isolation and medical observation? “There are many asymptomatic infections in this round of the epidemic. From an international perspective, the number of asymptomatic people infected with the new coronavirus in the early stage has gradually increased, especially after Omicron became the main epidemic strain recently, asymptomatic people. It can reach 80-90%. The current proportion of asymptomatic infections in Shanghai is similar to that of other countries and regions, mainly for the following reasons.
First, the virulence of the Omicron strain itself was reduced. Some research data show that the infection of the Omicron strain mainly involves the upper respiratory tract, and the lower respiratory tract is relatively rare, which significantly reduces the proportion of symptoms.
Second, the vaccination of large-scale populations plays a very important role in protecting the majority of susceptible populations. After analyzing the case studies, it was found that in all cases, the proportion of vaccination reached about 94%, the incidence of severe disease was reduced to 0.1%, and no case developed into critical disease. These data suggest that vaccines have a very important impact on reducing symptoms.
Third, more asymptomatic infections were screened out after active screening to increase the detection rate. With the advance of epidemiological investigations in large numbers, the screening capacity and scope have become larger. The attackers, close contacts, and risk groups were quickly brought under control. These measures allow for the rapid detection of infected people in the incubation period, and the proportion of asymptomatic cases in early active screening will also increase.
Wu Jinglei said that the key to controlling infectious diseases is to control the source of infection, cut off the route of transmission, and protect susceptible populations. Asymptomatic infection does not mean low infectivity, so centralized isolation measures must be implemented for asymptomatic infection to control the source of infection and block transmission. Secondly, it is the need for medical observation and management of asymptomatic infections. Some asymptomatic infections may change in their condition, especially in the elderly, those who have not been vaccinated, obese, and those with serious underlying diseases. Symptoms, or even develop into severe cases, are convenient for medical staff to detect and treat in time during the medical observation period. Regarding the treatment situation, they are similar to those with mild symptoms. Clinical observation and follow-up are carried out for these people, and risk assessment is carried out.
Source: China Youth Daily Client