When a positive IgM antibody is found, it should first be clear which pathogenic infection is present. Since there must be antigens if there are antibodies, and antigens must come from a more specific microorganism that can infect people, there will be a certain course of the disease, and only if it is clear which pathogen is present can we determine what the course of the disease is. If it is positive for IgM antibodies to the influenza virus, there can be obvious symptoms such as fever, cough, sputum, headache, and generalized aches and pains, and treatment should be directed at the pathogen, and antiviral treatment for the influenza virus is the application of oseltamivir. In the case of other pathogenic infections, such as IgM antibody positive for cytomegalovirus, although it indicates that cytomegalovirus infection is present, the adult does not have symptoms associated with it and can be left untreated. Anti-viral treatment with ganciclovir or, optionally, sodium phosphonate, is required only if there are symptoms caused by cytomegalovirus infection of the body, such as fever or liver function impairment.