Epidemiologic investigation to the first cluster of fever cases caused by human bocavirus in Beijing, 2017

ObjectiveTo understand the etiologic and epidemiologic characteristics of a cluster of human bocavirus (HBoV) infection cases in Fengtai district of Beijing and the circulation and evolution of HBoV in Beijing, and provide scientific evidence for the prevention and control of HBoV infection.

MethodsEpidemiologic investigation was performed for 13 children with fever, and 10 throat swabs were collected from them. The pathogens were identified by the multiplex combined real-time PCR detection kit for respiratory viruses. The HBoV VP1 gene region was specifically amplified and sequenced for the detected HBoV strains. The gene distance calculation and phylogenetic tree analysis were performed for the amplified sequences by using bioinformatics software DNAStar 7.1, Bioedit v7.0.9, and MEGA 6.0.6.

ResultsThe clinical symptoms of the children were mainly fever and cough. All the children with fever were classmates. Three HBoV positive samples were detected in 10 throat swabs, and the 3 HBoV strains were classified into type 1 indicated by the gene distance and phylogenetic tree analysis. The nucleotide sequences of the 3 HBoV strains shared 100% homology and the 3 strains were highly homologous to Beijing strain 311-BJ07, suggesting that the outbreak may be related to the circulating HBoV-1 strain in Beijing.

ConclusionThis cluster of fever cases was caused by HBoV-1 strain which are widespread in China. It suggested that HBoV-1 respiratory infection epidemic is serious. It is necessary to strengthen surveillance and research and develop effective HBoV-1 infection prevention and control measures.