title: Human metapneumovirus infection in the Canadian population.
abstract: Human metapneumovirus (hMPV), a newly discovered paramyxovirus, has been associated with acute respiratory tract infections (ARIs) ranging from upper ARIs to severe bronchiolitis and pneumonia. Important questions remain on the contribution of hMPV to ARIs and its impact on public health. During the 2001-2002 season, we conducted a collaborative study with four provincial public health laboratories to study the prevalence of this new virus in the Canadian population. A total of 445 specimens were collected from patients of all age groups with ARIs and were tested for the presence of hMPV by reverse transcription-PCR. Of these, 66 (14.8%) tested positive for hMPV. Positive specimens were found in all age groups and in all four provinces studied. Virus activity peaked in February and March. The age range of the patients with hMPV infection was 2 months to 93 years (median age, 25 years), with similar numbers of females (35%) and males (41%). Thirty-three percent (n = 22) of hMPV-infected patients were hospitalized; of these, 27% (n = 6) had rhinitis and pneumonia, 23% (n = 5) had bronchiolitis, and 9% (n = 2) had bronchitis. The hospitalization rates were significantly higher among patients <5 years of age (P = 0.0005) and those >50 years of age (P = 0.0044) than among those 6 to 50 years of age. Phylogenetic analysis of the F gene showed that two hMPV genetic clusters were cocirculating in the 2001-2002 season, and comparison with earlier studies suggests a temporal evolutionary pattern of hMPV isolates. These results provide further evidence of the importance of hMPV in ARIs, particularly in young children and elderly individuals.
authors.affiliation: National Microbiology Laboratory, Canadian Science Center for Human and Animal Health, Winnipeg, Manitoba, Canada.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Bastien
authors.forename: Diane
authors.initials: D
authors.lastname: Ward
authors.forename: Paul
authors.initials: P
authors.lastname: Van Caeseele
authors.forename: Ken
authors.initials: K
authors.lastname: Brandt
authors.forename: Spencer H S
authors.initials: SH
authors.lastname: Lee
authors.forename: Gail
authors.initials: G
authors.lastname: McNabb
authors.forename: Brian
authors.initials: B
authors.lastname: Klisko
authors.forename: Edward
authors.initials: E
authors.lastname: Chan
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002170:Canada / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D029121:Metapneumovirus / Q000235:genetics / Q000302:isolation & purification*; D008875:Middle Aged; D008969:Molecular Sequence Data; D018184:Paramyxoviridae Infections / Q000453:epidemiology* / Q000503:physiopathology / Q000821:virology; D010802:Phylogeny; D015995:Prevalence; D012141:Respiratory Tract Infections / Q000453:epidemiology* / Q000503:physiopathology / Q000821:virology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014760:Viral Fusion Proteins / Q000235:genetics
chemical_list: D014760:Viral Fusion Proteins