title: A household-based study of acute viral respiratory illnesses in Andean children.
abstract: BACKGROUND
  Few community studies have measured the incidence, severity and etiology of acute respiratory illness (ARI) among children living at high-altitude in remote rural settings.
  
  
  METHODS
  We conducted active, household-based ARI surveillance among children aged <3 years in rural highland communities of San Marcos, Cajamarca, Peru from May 2009 through September 2011 (RESPIRA-PERU study). ARI (defined by fever or cough) were considered lower respiratory tract infections if tachypnea, wheezing, grunting, stridor or retractions were present. Nasal swabs collected during ARI episodes were tested for respiratory viruses by real-time, reverse-transcriptase polymerase chain reaction. ARI incidence was calculated using Poisson regression.
  
  
  RESULTS
  During 755.1 child-years of observation among 892 children in 58 communities, 4475 ARI were observed, yielding an adjusted incidence of 6.2 ARI/child-year (95% confidence interval: 5.9-6.5). Families sought medical care for 24% of ARI, 4% were classified as lower respiratory tract infections and 1% led to hospitalization. Of 5 deaths among cohort children, 2 were attributed to ARI. One or more respiratory viruses were detected in 67% of 3957 samples collected. Virus-specific incidence rates per 100 child-years were: rhinovirus, 236; adenovirus, 73; parainfluenza virus, 46; influenza, 37; respiratory syncytial virus, 30 and human metapneumovirus, 17. Respiratory syncytial virus, metapneumovirus and parainfluenza virus 1-3 comprised a disproportionate share of lower respiratory tract infections compared with other etiologies.
  
  
  CONCLUSIONS
  In this high-altitude rural setting with low-population density, ARI in young children were common, frequently severe and associated with a number of different respiratory viruses. Effective strategies for prevention and control of these infections are needed.
authors.affiliation: From the *Division of Infectious Diseases, Department of Internal Medicine; †Department of Preventive Medicine; ‡Vanderbilt Vaccine Research Program, Division of Infectious Diseases, Department of Pediatrics; §Department of Pediatrics; ¶Department of Pathology, Microbiology, and Immunology, Vanderbilt University, Nashville, TN; ‖Instituto de Investigacion Nutricional, Lima, Peru; **Swiss Tropical and Public Health Institute, Basel, Switzerland; and ††Department of Biostatistics, Vanderbilt University, Nashville, TN.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Budge
authors.forename: Marie R
authors.initials: MR
authors.lastname: Griffin
authors.forename: Kathryn M
authors.initials: KM
authors.lastname: Edwards
authors.forename: John V
authors.initials: JV
authors.lastname: Williams
authors.forename: Hector
authors.initials: H
authors.lastname: Verastegui
authors.forename: Stella M
authors.initials: SM
authors.lastname: Hartinger
authors.forename: Monika
authors.initials: M
authors.lastname: Johnson
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Klemenc
authors.forename: Yuwei
authors.initials: Y
authors.lastname: Zhu
authors.forename: Ana I
authors.initials: AI
authors.lastname: Gil
authors.forename: Claudio F
authors.initials: CF
authors.lastname: Lanata
authors.forename: Carlos G
authors.initials: CG
authors.lastname: Grijalva
mesh_terms: D000818:Animals; D002675:Child, Preschool; D005191:Family Characteristics; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009297:Nasal Mucosa / Q000821:virology; D010568:Peru / Q000453:epidemiology; D015995:Prevalence; D060888:Real-Time Polymerase Chain Reaction; D012141:Respiratory Tract Infections / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014777:Virus Diseases / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D014780:Viruses / Q000145:classification* / Q000302:isolation & purification*