Pathogenesis of coronaviruses Under natural conditions all coronavirus infections use the respiratory or intestinal tract as the primary site of replication, and the pathophysiological changes that cause clinical symptoms in them are mainly the proliferation of the virus in the host cells, causing cellular damage and death. Thus, the entry of local antigens into the body stimulates the immune system to respond by causing the production of antibodies to limit these infections. Many coronaviruses therefore have no obvious signs, symptoms, or even biochemical changes, and the infection can only be detected by immunological tests. The risk of coronavirus infection is not easily isolated and cultured, and the etiologic mechanisms of human coronavirus are poorly understood. Human respiratory coronavirus is usually confined to the nasal mucosa, the ciliated epithelium of the trachea, and alveolar cells. Local immune responses are sufficient to overcome acute infection, and the development of systemic humoral immunity can prevent viral invasion of other organs. The virus causes damage to the epithelial tissues of the respiratory tract, but clinical symptoms do not necessarily occur. Human intestinal coronavirus selectively infects absorptive cells in the intestinal mucosa, causing atrophy of the villi. Different strains can selectively invade the small intestine, large intestine, or colon, and the clinical severity of the manifestations is highly variable, ranging from mild transient enteritis to rapidly progressive fatal diarrhea; the main reliance is on the local immune response to overcome intestinal infection. How to prevent coronavirus There is no good strategy to control coronavirus infection. It is not easy to culture the virus, the epidemic type has not yet been determined, and the pattern of the body’s response after infection is not clear enough, so it is not possible to talk about prevention with a vaccine, but analyzing the preliminary information available, it is presumed that there are not many virus types, and there is a certain immune protection after infection, so there is still the possibility of prevention with a vaccine. Since the characteristics of coronaviruses are still not well understood, there are no specific therapeutic drugs yet. In the laboratory, it has been found that antiviral drugs for the treatment of AIDS, protease inhibitors, such as Crestor, and antiviral drugs for the treatment of Ebola, Remdesivir, may have an inhibitory effect on coronaviruses. More research on treatment and prevention is expected to bring definitive evidence. Until effective therapeutic drugs and vaccines are available, frequent hand washing, less frequent visits to places with poor air circulation, minimal partying during the epidemic season, and striving to wear masks in crowded and confined environments are currently effective prevention methods during the high season of respiratory infections. The windows in the family should also be opened frequently to reduce cross-infection within the family. In addition, increasing outdoor exercise and improving personal fitness are all positive for disease prevention. Source: Dr. You Lai Reference: 1. Chinese Journal of Hospital Infection, Vol. 13, No. 11, 2003: Characteristics and prevention of coronavirus infection