title: Environmental and demographic risk factors for respiratory syncytial virus lower respiratory tract disease.
abstract: OBJECTIVE
  To critically review the literature examining risk factors for development of severe respiratory syncytial virus lower respiratory tract infection (RSV LRI).
  
  
  METHODS
  A literature review was performed with the use of a MedLine search strategy. Clinical evidence of putative risk factors was rated by means of the US Preventive Services Task Force recommendations, and the quality of the data was critically assessed. Nonmedical risk factors examined included race/ethnicity, age of acquisition of RSV, sex, birth during the first half of the RSV season, breast-feeding, malnutrition, maternal education, socioeconomic status, crowding/siblings, day care, and tobacco smoke exposure.
  
  
  RESULTS
  There was sufficient evidence available to conclude that (1) male sex, (2) age <6 months, (3) birth during the first half of the RSV season, (4) crowding/siblings, and (5) day care exposure are significant risk factors for severe RSV LRI. There was insufficient evidence to evaluate the effect of race/ethnicity on severe RSV LRI. The evidence for tobacco smoke exposure is mixed. Low maternal education (as a proxy for lower socioeconomic status), lack of breast-feeding, and malnutrition did not appear to increase the risk of severe RSV LRI or RSV hospitalization.
  
  
  CONCLUSIONS
  Male sex, young age, birth in the first half of the RSV season, day care attendance, and crowding/siblings are independent risk factors for the development of severe RSV LRI.
authors: Section of Infectious Diseases, The University of Colorado School of Medicine and The Children's Hospital, Denver, Colorado 80218, USA. eric.simoes@uchsc.edu
authors: Eric A F
authors: EA
authors: Simoes
mesh_terms: D001942:Breast Feeding; D002648:Child; D002675:Child, Preschool; D003710:Demography; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D014943:Global Health; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008171:Lung Diseases / Q000821:virology*; D008297:Male; D044342:Malnutrition / Q000150:complications; D018357:Respiratory Syncytial Virus Infections / Q000821:virology*; D012307:Risk Factors; D012621:Seasons; D012737:Sex Factors; D012959:Socioeconomic Factors