title: Seasonality, incidence, and repeat human metapneumovirus lower respiratory tract infections in an area with a high prevalence of human immunodeficiency virus type-1 infection.
abstract: BACKGROUND
  There is limited information regarding the epidemiology of human metapneumovirus (hMPV) from Africa, despite it being identified as a common pathogen in children with pneumonia.
  
  
  OBJECTIVE
  Determine the epidemiology of severe hMPV-associated lower respiratory tract infection (LRTI) in human immunodeficiency virus type-1 (HIV) infected and uninfected children.
  
  
  METHODS
  Nasopharyngeal aspirate samples from children hospitalized for LRTI between January 2000 and December 2002 were analyzed for common respiratory viruses using an immunofluorescence assay; and 2715 available nasopharyngeal aspirate samples were tested for hMPV by reverse-transcriptase polymerase chain reaction targeting its fusion protein. Phylogenetic analysis of the fusion (F) gene was performed on samples associated with repeat hMPV infections in the same child.
  
  
  RESULTS
  hMPV was identified perennially and was the second most commonly identified respiratory virus (11.3% versus 21.1% for respiratory syncytial virus, P < 0.0001) in HIV-uninfected children. The burden of hospitalization for hMPV-LRTI was 5.4 (95% CI: 3.5-7.5) fold greater in HIV-infected (2935 per 100,000) compared with HIV-uninfected children [575 (95% CI: 472-695) per 100,000]. HIV-infected children had greater evidence of bacterial coinfection and a higher mortality rate than did uninfected children. Repeat hMPV associated hospitalizations involved homologous (B2 subgroup) and heterologous (A1 and B2) hMPV.
  
  
  CONCLUSIONS
  There is a high burden of hMPV-LRTI and repeat severe infections occur from homologous and heterologous subgroups of the virus.
authors.affiliation: University of the Witwatersrand/Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Chris Hani-Baragwanath Hospital, Bertsham, South Africa. madhis@hivsa.com
authors.forename: Shabir A
authors.initials: SA
authors.lastname: Madhi
authors.forename: Herbert
authors.initials: H
authors.lastname: Ludewick
authors.forename: Locadiah
authors.initials: L
authors.lastname: Kuwanda
authors.forename: Nadia
authors.initials: N
authors.lastname: van Niekerk
authors.forename: Clare
authors.initials: C
authors.lastname: Cutland
authors.forename: Keith P
authors.initials: KP
authors.lastname: Klugman
mesh_terms: D001424:Bacterial Infections / Q000453:epidemiology; D002675:Child, Preschool; D005260:Female; D019085:Fluorescent Antibody Technique, Direct; D005838:Genotype; D015658:HIV Infections / Q000150:complications*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D029121:Metapneumovirus / Q000302:isolation & purification; D009305:Nasopharynx / Q000821:virology; D018184:Paramyxoviridae Infections / Q000150:complications / Q000453:epidemiology* / Q000401:mortality; D010802:Phylogeny; D011014:Pneumonia / Q000453:epidemiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012621:Seasons; D017422:Sequence Analysis, DNA; D013019:South Africa