Seroprevalence of IgG against conformational and linear capsid antigens of parvovirus B19 in Italian blood donors

Serum samples from 446 Italian blood donors between 18 and 65 years of age were analysed for the presence of IgG against parvovirus B19 capsid proteins VP1 and VP2 including conformational and linear epitopes. The overall prevalence of IgG against parvovirus B19 capsid proteins VP1 and VP2 against at least one antigen type was 79·1%. No significant difference was found between men and women. In the 18–27 years age group, 77·0% of the population had experienced infection with the virus, reaching 88·5% in the 48–57 years age group. The overall prevalence of IgG was 78·0% against conformational VP1+VP2 antigens, 74·9% against conformational VP2, 70·9% against linear VP1 and 23·3% against linear VP2 in the analysis of the IgG response against different conformational and linear epitopes of VP1 and VP2. Although IgG against conformational VP1+VP2, conformational VP2 and linear VP1 was present in more than 60% of subjects in all age groups, IgG against VP2 linear antigens was present in only 32% of subjects in the 18–27 years age group and then decreased to 20·5% in the 28–37 years age group. A different trend was noted when IgG positivity against linear and conformational epitopes was analysed separately in men and women. A significant increase was found in seroprevalence of IgG against VP2 conformational antigens with increasing age in males and a significant decrease in seroprevalence of IgG against VP2 linear antigens in women with increasing age.