Estimating the Risk of Parvovirus B19 Infection in Blood Donors and Pregnant Women in Japan

Abstract

BackgroundSeroepidemiological study of parvovirus B19 has not taken place for some 20 years in Japan. To estimate the risk of parvovirus B19 infection in Japan among blood donors and pregnant women in this century, a seroepidemiological survey and statistical modeling of the force of infection were conducted.Methodology/Principal FindingsThe time- and age-specific seroprevalence data were suggestive of strong age-dependency in the risk of infection. Employing a piecewise constant model, the highest forces of infection of 0.05 and 0.12 per year were observed among those aged 0–4 and 5–9 years, respectively, while estimates among older individuals were less than 0.01 per year. Analyzing the antigen detection data among blood donors, the age-specific proportion positive was highest among those aged 30–39 years, agreeing with the presence of dip in seroprevalence in this age-group. Among pregnant women, up to 107 fetal deaths and 21 hydrops fetalis were estimated to have occurred annually across Japan.ConclusionsSeroepidemiological profiles of PVB19 infection in Japan was characterized with particular emphasis on the risk of infection in blood donors and the burden of infection among pregnant women. When a vaccine becomes available in the future, a similar seroepidemiological study is expected to play a key role in planning the appropriate immunization policy.

Human Parvoviruses

“…Fetal demise was recognized early and has been extensively reviewed (488)(489)(490)(491)(492)(493)(494)(495)(496)(497)(498). From seroepidemiology, an annual loss of 120 fetuses was calculated for Japan (499), and about twice this number might be extrapolated for the United States. Congenital malformations due to B19V are rare, but occasionally neonates who survive in utero infection may have hematological abnormalities similar to those of persistent B19V infection (see below).…”

Current status of percutaneous umbilical cord blood sampling in Japan

“…Furthermore, the rate of fetal anemia related to red‐cell alloimmune disorders is expected to decrease. Thus it is anticipated that parvovirus B19 infection might overtake red‐cell alloimmune disorders as one of the most common indications for PUBS …”

Investigating the immunizing effect of the rubella epidemic in Japan, 2012-14

“…Continued monitoring of susceptible age groups by seroepidemiological survey would be essential, as they permit estimating the epidemic size and designing the most efficient vaccination strategy. 9,10…”