title: Genetic variability of human metapneumovirus amongst an all ages population in Cambodia between 2007 and 2009.
abstract: First identified in 2001, human metapneumovirus (HMPV) is a novel pathogen and causative agent of acute respiratory tract infection. Re-infection with HMPV is common, and currently there is no available vaccine against HMPV infection. Two genotypes of HMPV have been identified, A and B, both of which can be divided further into at least two distinct sub-genotypes. Here we report the results of the first study to investigate the genetic variability of HMPV strains circulating within Cambodia. The overall incidence of HMPV infection amongst an all-ages population of patients hospitalised with ALRI in Cambodia during 3 consecutive years, between 2007 and 2009, was 1.7%. The incidence of HMPV infection was highest amongst children less than 5 years of age, with pneumonia or bronchopneumonia the most frequent clinical diagnoses across all age groups. The incidence of HMPV infection varied annually. As anticipated, genetic diversity was low amongst the conserved F gene sequences but very high amongst G gene sequences, some strains sharing as little as 56.3% and 34.2% homology at the nucleotide and amino acid levels, respectively. Simultaneous co-circulation of strains belonging to the HMPV sub-genotypes B1, B2 and lineage A2b, amongst patients recruited at 2 geographically distinct provincial hospitals, was detected. Sub-genotype B2 strains were responsible for the majority of the infections detected, and a significant (p=0.013) association between infection with lineage A2b strains and disease severity was observed.
authors.affiliation: Institut Pasteur in Cambodia, Réseau International des Instituts Pasteur, 5 Monivong blvd, PO Box 983, Phnom Penh, Cambodia.
authors.forename: Alicia
authors.initials: A
authors.lastname: Arnott
authors.forename: Sirenda
authors.initials: S
authors.lastname: Vong
authors.forename: Mardy
authors.initials: M
authors.lastname: Sek
authors.forename: Monica
authors.initials: M
authors.lastname: Naughtin
authors.forename: Julien
authors.initials: J
authors.lastname: Beauté
authors.forename: Sareth
authors.initials: S
authors.lastname: Rith
authors.forename: Bertrand
authors.initials: B
authors.lastname: Guillard
authors.forename: Vincent
authors.initials: V
authors.lastname: Deubel
authors.forename: Philippe
authors.initials: P
authors.lastname: Buchy
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002160:Cambodia / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D005814:Genes, Viral; D014644:Genetic Variation; D049674:History, 21st Century; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D029121:Metapneumovirus / Q000145:classification / Q000235:genetics*; D008875:Middle Aged; D008969:Molecular Sequence Data; D018184:Paramyxoviridae Infections / Q000453:epidemiology* / Q000266:history; D010802:Phylogeny; D011159:Population Surveillance; D012367:RNA, Viral / Q000235:genetics; D012621:Seasons; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: D012367:RNA, Viral