1. Who are the asymptomatic infected people in novel coronavirus?

Asymptomatic infected persons in COVID-19 (hereinafter referred to as asymptomatic infected persons) refer to those who have no relevant clinical symptoms, such as fever, cough, sore throat and other symptoms and signs that can be perceived by themselves or recognized clinically, but are positive for COVID-19 pathogens in respiratory tract and other specimens. Asymptomatic infection can be divided into two situations:

1, the infected person was positive for nucleic acid detection. After the incubation period of 14 days, there are no symptoms and signs that can be perceived or clinically recognized, and it is always asymptomatic infection;

2. The infected person was positive for nucleic acid detection, and there were no self-feeling or clinically recognizable symptoms and signs when sampling, but then some clinical manifestations appeared, that is, they were in the state of "asymptomatic infection" in the incubation period.

Second, how to find asymptomatic infected people?

At present, asymptomatic infected people are actively found through the following channels:

1, which is the active detection of close contacts of novel coronavirus cases during medical observation;

2. Carry out active detection in cluster epidemic investigation;

3. Actively detect the exposed population in the process of tracking the source of infection in novel coronavirus;

4. It is to actively detect some people with travel history and residence history in areas where novel coronavirus cases continue to spread at home and abroad.

Third, are asymptomatic infected people contagious?

According to the monitoring data of close contacts carried out by the state and some provinces, there are second-generation cases of close contacts of asymptomatic infected people. In the epidemiological investigation, individual cases of asymptomatic infection caused by cluster epidemic were found. A small sample study shows that the viral load in the respiratory tract samples of asymptomatic infected people is not much different from that of confirmed cases.

Based on the current monitoring and research, asymptomatic infected people are contagious, but further scientific research is needed on the length of infection period, infectivity and transmission mode. Some experts believe that pathogen nucleic acid can be detected in the respiratory tract samples of asymptomatic infected people, but because there are no clinical symptoms such as cough and sneezing, the chances of pathogens being excreted from the body are relatively less than those of confirmed cases.

4. How can the public wear masks scientifically? Under what circumstances can you not wear a mask?

At home and outdoors, there is no crowd gathering and good ventilation. Protective suggestion: Don't wear a mask.

In crowded places, such as offices, shopping malls, restaurants, conference rooms, workshops, etc. ; Or take a van elevator, bus, etc. Protection suggestion: In low-risk areas, spare masks (disposable medical masks or medical surgical masks) should be carried, and masks should be worn when in close contact with others (less than or equal to 1 m). Wear disposable medical masks in high-risk areas.

For people with cold symptoms such as coughing or sneezing.

For those who live with people who are isolated at home and discharged from the hospital.

Verb (abbreviation for verb) Precautions for using a mask:

1. Respiratory protective equipment includes masks and masks. Wash your hands before putting on gloves and after taking them off.

2. Pay attention to before and after wearing a mask. The mask should cover the nose and mouth, and adjust the nose clip to fit the face.

3. When wearing, avoid touching the inside and outside of the mask with your hands, and remove the mask by stirring the strings at both ends.

4. Wearing multiple masks can not effectively increase the protective effect, but increase the respiratory resistance, which may also damage the sealing performance.

5. There is no evidence to prove the effectiveness of various measures such as mask cleaning and disinfection.

6. Disposable medical masks and surgical masks are limited in use, and the cumulative use shall not exceed 8 hours. Occupational exposure personnel shall not use masks for more than 4 hours and shall not use them repeatedly.