title: Human rhinovirus infections in rural Thailand: epidemiological evidence for rhinovirus as both pathogen and bystander.
abstract: BACKGROUND
  We describe human rhinovirus (HRV) detections in SaKaeo province, Thailand.
  
  
  METHODS
  From September 1, 2003-August 31, 2005, we tested hospitalized patients with acute lower respiratory illness and outpatient controls without fever or respiratory symptoms for HRVs with polymerase chain reaction and molecularly-typed select HRVs. We compared HRV detection among hospitalized patients and controls and estimated enrollment adjusted incidence.
  
  
  RESULTS
  HRVs were detected in 315 (16%) of 1919 hospitalized patients and 27 (9.6%) of 280 controls. Children had the highest frequency of HRV detections (hospitalized: <1 year: 29%, 1-4 year: 29%, ≥ 65 years: 9%; controls: <1 year: 24%, 1-4 year: 14%, ≥ 65 years: 2.8%). Enrollment adjusted hospitalized HRV detection rates were highest among persons aged <1 year (1038/100,000 persons/year), 1-4 years (457), and ≥ 65 years (71). All three HRV species were identified, HRV-A was the most common species in most age groups including children aged <1 year (61%) and all adult age groups. HRV-C was the most common species in the 1-4 year (51%) and 5-19 year age groups (54%). Compared to controls, hospitalized adults (≥ 19 years) and children were more likely to have HRV detections (odds ratio [OR]: 4.8, 95% confidence interval [CI]: 1.5, 15.8; OR: 2.0, CI: 1.2, 3.3, respectively) and hospitalized children were more likely to have HRV-A (OR 1.7, CI: 0.8, 3.5) or HVR-C (OR 2.7, CI: 1.2, 5.9) detection.
  
  
  CONCLUSIONS
  HRV rates were high among hospitalized children and the elderly but asymptomatic children also had substantial HRV detection. HRV (all species), and HRV-A and HRV-C detections were epidemiologically-associated with hospitalized illness. Treatment or prevention modalities effective against HRV could reduce hospitalizations due to HRV in Thailand.
authors.affiliation: Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America. afry@cdc.gov
authors.forename: Alicia M
authors.initials: AM
authors.lastname: Fry
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Lu
authors.forename: Sonja J
authors.initials: SJ
authors.lastname: Olsen
authors.forename: Malinee
authors.initials: M
authors.lastname: Chittaganpitch
authors.forename: Pongpun
authors.initials: P
authors.lastname: Sawatwong
authors.forename: Somrak
authors.initials: S
authors.lastname: Chantra
authors.forename: Henry C
authors.initials: HC
authors.lastname: Baggett
authors.forename: Dean
authors.initials: D
authors.lastname: Erdman
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002648:Child; D002675:Child, Preschool; D006760:Hospitalization; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007251:Influenza, Human / Q000150:complications / Q000821:virology; D008875:Middle Aged; D010850:Picornaviridae Infections / Q000150:complications / Q000453:epidemiology* / Q000821:virology*; D012229:Rhinovirus / Q000302:isolation & purification / Q000502:physiology*; D012424:Rural Population / Q000706:statistics & numerical data*; D012621:Seasons; D013785:Thailand / Q000453:epidemiology; D055815:Young Adult