Original title: Fuyang or secondary infection? Is the condition more serious following the second infection?Experts
Chinanews.com, Beijing, December 20th (Reporter Du Yan) Symptoms reappeared following being “positive”. Is it “recovery” or a secondary infection? Is the condition more serious following the second infection? Beijing disease control experts answered questions in detail.
What is a secondary infection? How to determine is the second infection?
Experts said that “secondary infection” refers to a person who has been infected by the new coronavirus, has fully recovered, and then is infected once more by the new coronavirus.
Experts believe that different countries or regions have different definitions for secondary infection, but the basic condition is that there must be a period of time following diagnosis. For example, the European Center for Disease Control and Prevention believes that a true secondary infection can only be diagnosed when the virus from the primary infection has been completely cleared and there has been sufficient time for an immune response to develop. The United Kingdom defines the interval between secondary infections as at least 90 days, while the United States defines the interval between 60-90 days. Secondary infection needs to be comprehensively judged by combining symptoms and signs, clinical manifestations, immune response, gene sequencing and other indicators.
Is the probability of secondary infection high?
Experts said that the probability of secondary infection is mainly related to the level of human immunity and the variation of virus strains. The higher the immune response indicators such as antibodies, the smaller the variation of the virus strain, and the lower the incidence of secondary infection. The current study showed that Omicron caused a slightly higher rate of secondary infections than earlier variants. But in general, the probability of secondary infection of the new coronavirus in a short period of time is still relatively low.
A study published in the top international medical journal “New England Journal of Medicine” showed that following the initial infection of non-Omicron strains in unvaccinated persons, the incidence of secondary infection with Omicron BA.1 or BA.2 was 135 days following the start of follow-up. About 1.1%; following the initial infection with Omicron BA.1 or BA.2, the incidence of secondary infection with BA.4 and BA.5 variants was regarding 2.1%. A study in South Korea shows that during the epidemic of the Omicron variant in early 2022, the secondary infection rate in South Korea will increase compared with that of the Delta variant. has declined.
So, how to distinguish “Fuyang” from secondary infection?
Experts said that “Fuyang” means that the symptoms of the infected person basically disappeared, and following reaching the discharge standard, the nucleic acid was tested once more and found to be positive. “Fuyang” patients generally have no obvious clinical symptoms, and are basically not contagious; the second infection is equivalent to a new infection, which is a re-infection following recovery. Generally speaking, clinical symptoms may appear, and the nucleic acid load is relatively low. High and contagious.
What is the relationship between antibody levels and secondary infection?
Several studies have shown that immunity from vaccination or natural infection can reduce the incidence of secondary infections, experts said. People with low immunity or low antibody levels are relatively more at risk of secondary infection. Therefore, this group of people should also pay attention to strengthening personal protection, and timely receive the new crown vaccine or strengthen immunization.
Is the reappearance of symptoms shortly following fever a secondary infection?
Experts pointed out that reappearing symptoms shortly following fever does not belong to secondary infection. After the general population is infected by the virus, the immune system is activated immediately, and the levels of cellular immunity and antibodies continue to increase. Generally, the antibody level reaches a peak following two weeks and maintains a high level in a short period of time, which has a certain protective effect on the body. Before the human body recovers from the new coronavirus infection, because the immune system is already functioning, the possibility of re-infection with the same or different new coronavirus variants in a short period of time is extremely small.
So, is the condition more serious following the second infection?
Experts pointed out that at present, reports of severe diseases caused by repeated infection of the new coronavirus are rare. The severity of the disease following repeated infection may be related to the dose of virus infection, the variant strain of the new crown, and the health status of the individual. But overall, the risk of superinfection leading to severe illness is low.
