The virus may follow the sewer to infect the residents of the same building, but the likelihood is small, so there is no need to worry too much about such a transmission route. Viruses are generally infectious, and after infection, the virus multiplies in the body and can attack the respiratory and gastrointestinal tracts, resulting in a certain amount of virus remaining in sputum, vomit, feces, and other excretions, especially viral gastroenteritis. In addition, neocoronavirus has been detected in the feces of patients with neocoronary pneumonia, indicating a theoretical risk of fecal transmission of neocoronavirus. The virus enters the sewer with the excrement and survives in a suitable environment, and can enter the bathroom of the same building through the sewer and attach to towels, toothbrushes, and other items, causing infection in others after contact. However, this kind of transmission has certain limitations, mostly in residential buildings in disrepair, because there is no water in the sewer U-shaped pipe, the original water seal isolation layer disappeared, resulting in the spread of the virus. For households with normal structure and standing water in the U-shaped pipe, the water seal prevents the spread of the virus, so there is no need to worry too much about infecting households in the same building. For the sake of personal health and safety, if there is a sewer back odor, leaks and other situations, we must promptly find professionals to repair, while ensuring that the bathroom, kitchen, balcony and other areas of the floor drain there is enough water to form a water seal effect. Daily should do diligently open the window or open the exhaust fan ventilation, before meals, before and after the stool, hand washing, and after using the toilet, the toilet cover and then flush, but also help to isolate the virus effect.