Can a person be re-infected with COVID-19, Who is more susceptible to infection? Is it possible for a person to have multiple infections due to different strains?
With the increase of the number of people infected with COVID-19, secondary infection has become the focus of public attention. Recently, Liu Hongyan, the head of the Infectious Diseases Department of Shenyang Sixth People’s Hospital and the leader of the COVID-19 treatment expert group, answered questions about secondary infection.
What is secondary infection?
“Secondary infection refers to a person who has been infected COVID-19, fully recovered, and then is infected again.” Liu Hongyan said that secondary infection is usually symptomatic, with relatively low CT value of nucleic acid, high viral load, and infectious. If the nucleic acid is positive for more than one month after rehabilitation, the possibility of re-infection is relatively high. In general, patients with normal immune function can obtain protection for between 3 to 6 months after infection and rehabilitation. The probability of secondary infection during this period is relatively low, so don’t worry too much.
Which people are more susceptible to infection? Experts say people with low immune function are more likely to be infected again. “For example, the immune function of the elderly has deteriorated. After recovering from infection, the duration of protection is relatively short. There are also infants under three years old whose immune function is not perfect, and the duration of protection after recovery may be relatively short,” Liu Hongyan said. In addition, people with low immune function, such as AIDS patients or immunosuppressive drug users, have a relatively short protection period and a relatively high risk of secondary infection.
Is it possible for a person to have multiple infections due to different strains?
Since the immune system is already functioning, it is less likely to be re-infected the same or different COVID-19 variants in a short time after infection. According to the current data, the risk of secondary infection of the Omicron strain is higher than that of the original strain, including Delta and the original strain. “After infection, there is cross protection for variants similar to the virus, but if the virus continues to mutate or is a distant strain, the risk of infection will increase,” Liu Hongyan said. In addition, experts from Shenyang CDC said that there are other respiratory infectious diseases in winter and spring, such as influenza, adenovirus, respiratory syncytial virus, etc. Therefore, it is necessary to continue to maintain good living and health habits, take proper exercise, eat reasonably, wear masks regularly, wash hands frequently, strengthen hand disinfection, open more windows for ventilation, maintain a safe social distance, and pay attention to cough etiquette.