[Relationship between viral load of human bocavirus and clinical characteristics in children with acute lower respiratory tract infection].

OBJECTIVE: To investigate the prevalence of human bocavirus (HBoV) in children with acute lower respiratory tract infection and to explore the relationship between the viral load of HBoV and the clinical characteristics of acute lower respiratory tract infection in children.
METHODS: A total of 1 554 nasopharyngeal aspirates from children who were hospitalized due to acute lower respiratory tract infection between March 2011 and March 2014 were collected. Quantitative real-time PCR was used to detect 12 RNA and 2 DNA viruses, adenovirus (ADV) and HBoV, and to measure the viral load of HBoV in HBoV-positive children. A comprehensive analysis was performed with reference to clinical symptoms and indicators.
RESULTS: In the 1 554 specimens, 1 212 (77.99%) were positive for viruses, and 275 (17.70%) were HBoV-positive. In HBoV-positive cases, 94.9% were aged <3 years, and there were more males than females. In the 275 HBoV-positive cases, 45 (16.36%) had single infection, and 230 (83.64%) had mixed infection. There was no significant difference in viral load between children with single infection and mixed infection (P>0.05). The patients with fever had a significantly higher viral load than those without fever (P<0.05). The children with wheezing had a significantly higher viral load than those without wheezing (P<0.05). There was no significant difference in viral load between children with mild, moderate, and severe acute lower respiratory tract infection (P>0.05).
CONCLUSIONS: HBoV is one of the important pathogens of acute lower respiratory tract infection in children. Children with a higher viral load of HBoV are more likely to experience symptoms such as fever and wheezing. However, the severity of disease and mixed infection are not significantly related to viral load.