Recently, Guangzhou, Beijing, Chongqing, Zhengzhou and other places announced to adjust nucleic acid testing policies, optimize the scope of nucleic acid testing objects, cancel all nucleic acids in many places, and resume operation of some shopping malls and buses. All kinds of epidemic prevention optimization measures are beneficial to the travel, life and work of the masses. However, recently, the number of newly infected people in COVID-19 has exceeded 30000 for several consecutive days, and when the temperature drops sharply in winter, personal epidemic prevention is particularly important at this time. What should we pay attention to when doing nucleic acid in winter? How to protect yourself and your fellow residents during home isolation? After the COVID-19 patient turns negative from the shelter and goes home, does the home need to be thoroughly disinfected? The experts from the disease control department answered the common situations one by one. What should we pay attention to when doing nucleic acid in winter? On November 29, Xu Hejian, Vice Minister of the Publicity Department of the Beijing Municipal Party Committee, Director of the Information Office of the Beijing Municipal People's Government, and spokesman of the Beijing Municipal People's Government, answered a reporter's question, saying that the weather has cooled down recently, and the majority of citizens have worked hard to do nucleic acid outside, so they should do a good job of cold prevention and warmth preservation, and protect themselves throughout the process. Xu Hejian stressed that it is necessary to wear masks in a standardized way. Children, the elderly and people with basic diseases are recommended to wear N95 masks; Keep a safe social distance when queuing. Line up in a straight line, not in a zigzag line; When scanning and registering, do not touch the nucleic acid detection station, and do not put your mobile phone and ID card on the table; The person in front should not go forward immediately after the sampling is completed. After the previous person finishes the sampling and leaves and the medical staff finishes the manual elimination, they should take out a new cotton swab before going forward. They should only take off the mask for a short time during the sampling and hold their breath. After the sampling is completed, they should wear the mask and leave immediately; After going home, immediately wash your hands under flowing water with the "seven step washing method". How to protect yourself and your fellow residents during home isolation? On November 30, Liu Xiaofeng, deputy director of the Beijing Municipal Center for Disease Control and Prevention, gave three tips on how to protect isolated persons and cohabitants at home: cooperate with various prevention and control measures, reduce contact with cohabitants, and disinfect the environment. Home isolation and cohabitation personnel shall be subject to the unified management of the community (village), strictly stay at home, do not go out, do not visit, and cooperate with nucleic acid testing, antigen self testing, health monitoring and other prevention and control measures. If the antigen self test is positive or COVID-19 related symptoms appear, please report to the community immediately to reduce the risk of transmission of the epidemic in the family, and cooperate with the implementation of nucleic acid testing, transportation and other control measures, obey the arrangements during transportation, standardize the wearing of N95 medical protective masks, and maintain a safe social distance. Isolators at home should try to choose relatively independent and well ventilated rooms, and open windows every day for ventilation; When the room is ventilated by air conditioning system, split air conditioning shall be selected; Tables and stools can be placed outdoors as a non-contact transfer place; The room should be equipped with personal protective equipment and disinfection products such as thermometer, paper towels, masks, disposable gloves, disinfectants, etc; Daily life and meals shall be kept in the same room as far as possible, so as to reduce contact with fellow residents. Towels, tableware and other daily necessities shall not be shared, and a safe distance shall be kept when contact is necessary. Both parties shall wear masks and do a good job of personal protection. If conditions permit, isolation personnel at home should try to use a separate toilet, which can be disinfected once a day. If family members share the toilet