Human bocavirus amongst an all-ages population hospitalised with acute lower respiratory infections in Cambodia.

Abstract : BACKGROUND: Human bocavirus (HBoV) is a novel parvovirus that is associated with respiratory and gastrointestinal tract disease. OBJECTIVES: To investigate the prevalence and genetic diversity of HBoV amongst hospitalized patients with acute lower respiratory infection (ALRI) in Cambodia. STUDY DESIGN: Samples were collected from 2773 patients of all ages hospitalised with symptoms of ALRI between 2007 and 2009. All samples were screened by multiplex RT-PCR/PCR for 18 respiratory viruses. All samples positive for HBoV were sequenced and included in this study. RESULTS: Of the samples tested, 43 (1*5%) were positive for HBoV. The incidence of HBoV did not vary between the consecutive seasons investigated, and HBoV infections were detected year-round. The incidence of HBoV infection was highest in patients aged < 2 years, with pneumonia or bronchopneumonia the most common clinical diagnosis, regardless of age. A total of 19 patients (44%) were co-infected with HBoV and an additional respiratory pathogen. All isolates were classified as HBoV type 1 (HBoV-1). High conservation between Cambodian NP1 and V1V2 gene sequences was observed. CONCLUSIONS: Human bocavirus infection can result in serious illness, however is frequently detected in the context of viral co-infection. Specific studies are required to further understand the true pathogenesis of HBoV in the context of severe respiratory illness.