Molecular epidemiology of human metapneumovirus in children with acute lower respiratory tract infections in Shanghai

Abstract

To understand the clinical and molecular epidemiologic features of human metapneumovirus (hMPV) in children with acute lower respiratory tract infection (ALRTI) from Oct. 2006 to Feb. 2008 in Shanghai. We established a reliable and stable diagnostic method of TaqMan-MGB real-time reverse transcription polymerase chain reaction (RT-PCR) to detect hMPV in the clinically manifested respiratory samples. To understand the role of hMPV in children's ALRTI, we tested other seven common respiratory viruses, using direct immunofluorescence assays (DFA). Data was analysed on the rates of detection among patients with respiratory bacteria, mycoplasma pneumonia and chlamydia among the targeted samples and enrolled patients to display the spectrum of respiratory pathogens and the changing pattern of pathogens with time. Of 622 samples, hMPV was detected to be positive in 24 (3.86%) samples. However, the prevalence of hMPV in the winter season of 2006 to 2007 was higher than that in the winter season of 2007 to 2008. The majority of children infected with hMPV were younger than 5 years old. Data from phylogenetic tree analysis further demonstrated A2 genotype hMPV circulating during the study period. Respiratory viruses were important respiratory pathogens among children with ALRTI and respiratory syncytial virus. They were the two most common virus which might be followed by hMPV that causing the diseases. We confirmed that hMPV as an important pathogen of ALRTI in the children from Shanghai.