Incidence of parvovirus B19 infection. Seroepidemiologic studies

: Anti-B19-IgG antibodies were tested for by the ELISA method in 768 sera, 76 from children and juveniles, aged 1-15 years, attending the Outpatients Department of the Children's Clinic, University of Munich, and 692 from persons, aged 18-68 years, attending the blood donor service of the Bavarian Red Cross in Munich. 38.4% of sera were positive, with a significant difference between men and women (32.5% vs. 47.5%, P less than or equal to 0.01). A fresh B19 infection was present in 42 subjects by demonstrating anti-B19-IgM in the ELISA test. The sera came from seven patients with infectious erythema, 26 with skin rash of uncertain cause, two with erythroblastosis fetalis, two with enteritis, one with transitory anaemia, one with juvenile polyarthritis, one with lymphadenitis and arthralgia, and two with an asymptomatic course. Viral B19-DNA was demonstrated by nucleic acid hybridization in a blood unit from an asymptomatic blood donor and in amniotic fluid in a case of erythroblastosis fetalis.