Detection and genome analysis of human bocavirus 1-4 from hospitalized children with acute lower respiratory tract infection and symptoms of wheezing in Shanghai.

The aim of this study was to elucidate the clinical and molecular epidemiology of human bocavirus (HBoV)1-4 in hospitalized children in Shanghai suffering from acute lower respiratory tract infection with symptoms of wheezing. HBoV1-4 was detected by nested PCR from 275 nasopharyngeal secretion samples collected from hospitalized children. The HBoV-positive DNA sequences were aligned and phylogenetic trees were constructed. The detection rate of HBoV1 was 5.45% (15/275), which was second only to respiratory syncytial virus (RSV). HBoV1 was co-detected with other potential pathogens in most of the samples. No sample was HBoV2‑4-positive. Homology analysis of the partial VP1/VP2, NP1 and NS1 sequences revealed that these genes belonged to the same HBoV1 genotype. Furthermore, the phylogenetic analysis indicated that these epidemic strains clustered on one independent branch. Our results demonstrate that HBoV1 may be one of the common pathogens responsible for the hospitalization of children with acute lower respiratory tract infection and symptoms of wheezing in Shanghai. HBoV1 infection cases are often associated with other pathogens. The viral strains responsible for winter epidemics circulating among children in Shanghai belonged to the same genotype of HBoV1; thus, they may be derived from one common ancestor.