Molecular screening of the human parvoviruses B19 and bocavirus 1 in the study of congenital diseases as applied to symptomatic pregnant women and children

Abstract

Introduction B19 virus (B19V) and bocavirus 1 (HBoV1) are human pathogenic parvoviruses that are prevalent worldwide and are responsible for a diverse and not yet fully established spectrum of clinical manifestations. Objective To screen B19V and HBoV1 in patients with clinical manifestations associated with acquisition of the infection during gestation. Methods A retrospective, observational study was performed that included serum samples from patients without a previous known aetiology. B19V and HBoV1 were determined by end-point PCR. Positive samples were genotyped. Results A total of 106 serum samples were analysed, 61 from pregnant women and 45 from neonates and paediatric patients. None were positive for HBoV1, while B19V was detected in 37/106 [34.9 %, 95 % confidence interval (CI): 26.5–44.4] of the samples studied. In the group of pregnant women, 28/61 (45.9 %, 95 % CI: 34.0–58.3) were B19V-positive, and 2 of them had foetal anaemia followed by hydrops and foetal death, 3 were associated with a history of recurrent pregnancy loss and there was 1 case of spontaneous abortion. B19V was also detected in cases of maternal febrile exanthema, polyhydramnios, oligohydramnios and foetal ascites. In the group of children, 9/45 (20.0 %, 95 % CI: 10.9–33.8) neonatal patients were B19V-positive, and this was associated with foetal hydrops, TORCH syndrome and cardiac alterations. The nucleotide sequences analysed confirmed the identity of B19V genotype 1. Conclusions We found no evidence to indicate the presence of HBoV1 in maternal blood or in the newborns/paediatric patients (hence providing no support for the supposed vertical transmission). On the other hand, the high frequency of B19V in the pathologies studied indicates the importance of molecular diagnosis in both the mother and the child. Future efforts should contribute to early detection and characterization of infections.

An Outbreak of Parvovirus B19 in Israel

“…Importantly, it has been demonstrated that during surges, secondary attack rates are significant [28], as has been demonstrated by our data as well. Rates have also been shown to be highly dependent on occupation deriving substantial exposure opportunities, such as daycare center workers or schoolteachers, among whom infection rates of susceptible women can climb to 20 to 30 percent [28], while hydrops fetalis and fetal death have also been demonstrated to rise during outbreaks [25,41]. Increased rates in this population could also be related to secondary transmission in households, a hypothesis that should be researched in future studies.…”

“…Lifetime prevalence of B19V is relatively high throughout the world; where genotypes 1 is prevalent worldwide, genotype 2 is rare and currently considered ancestral to genotype 1, while genotype 3 can be found primarily in Africa and South America; the intergenotype genetic divergence is up to 13% [25,26]. Prevalence increases with age and varies across geographic locations, with school age seroprevalence of 20-60% and up to 80% in adults in Western countries [27].…”

Diagnosis and clinical significance of Human bocavirus 1 in children hospitalized for lower acute respiratory infection: molecular detection in respiratory secretions and serum

“…Extracts were stored at −20 °C for later use in subsequent end-point PCR assays for detection of HBoV1, targeting a 354 bp sequence of the NP1 gene as performed previously [3, 22, 23]⁠. PCR products were visualized in 8.5 % polyacrylamide gels stained with silver solution (0.11 M AgNO 3 ) [24]⁠.…”

Molecular genetic and clinical aspects of socially relevant viruses underlying congenital diseases

“…Штаммы с последовательностями, идентичными прототипным штаммам В19, Au и Wi, составляют генотип 1. К генотипу 2 относятся изоляты HaAM и K71 (прототипы А6 и LaLi), а к 3 генотипу -изоляты штаммов V9 и D91.1 [33,95]. В соответствии с различиями нуклеотидных последовательностей геномов геновиды подразделяются на штаммы 1А, 1В, 2А, 3А и 3В.…”