Parvovirus B19 testing is generally not used to test those with mild and uncomplicated infections. It is typically used to detect a current infection or determine immunity in those who are at an increased risk of complications, such as those with sickle cell anemia. IgM antibodies are the first to be produced by the body in response to a parvovirus infection. They are present in most individuals within a week or two after the initial exposure. IgM antibody production rises for a short time period and then declines. Eventually, the level of parvovirus IgM antibody usually falls below detectable levels.