Absence of human bocavirus from deceased fetuses and their mothers

Abstract

Background The human bocavirus (HBoV), a newly discovered parvovirus, is closely related to the bovine parvovirus and the canine minute virus, which are known to cause adverse pregnancy outcomes. Another human parvovirus, B19, can lead to fetal hydrops, miscarriage and intrauterine fetal death (IUFD). Objectives To determine the prevalence of HBoV DNA in aborted fetuses and IUFDs. The HBoV serology of the mothers was also studied. Study design We retrospectively studied all available fetuses ( N = 535) autopsied during 7/1992–12/1995, and 1/2003–12/2005 in Helsinki, Finland. All available formalin-fixed paraffin-embedded fetal tissues – placenta, heart and liver – of 120 miscarriages, 169 IUFDs, and 246 induced abortions were studied by quantitative PCR. We also measured the HBoV IgM and IgG antibodies in the corresponding maternal sera ( N = 462) mostly of the first trimester. The IgM-positive sera underwent HBoV PCR. Results None of the fetal tissues harbored HBoV DNA. A total of 97% (448/462) of the mothers were positive for IgG antibodies to HBoV, while only 0.9% (4/462) exhibited HBoV-specific IgM antibodies without viremia or respiratory symptoms. One IgM-positive mother had an unexplained fetal loss. Conclusions We did not find HBoV DNA in any of the deceased fetuses. Almost all pregnant women were HBoV-IgG positive.