Risk factors for febrile, presumed viral illness in the first ten weeks of life.

Objective: We attempted to identify demographic and environmental factors associated with development of febrile, presumed viral illness in infants < or = 10 weeks old.

Study Design: The study was conducted in a large, urban pediatric hospital and outpatient clinics. Infants < or = 10 weeks old admitted to the hospital for a febrile illness but discharged with a presumed viral illness as the cause of the fever (n = 106) were compared with afebrile infants who came for clinic appointments (n = 87). Thirty-three infants found to have a bacterial source of illness were dropped from analysis.

Results: Recent exposure to an acute respiratory illness in the home (p < 0.0001), a previous visit to the doctor that was unrelated to the hospitalization (p < 0.002), having a sibling in school or day care (p < 0.007), and exposure to two or more smokers in the home (p < 0.011) were associated with development of a presumed viral illness with fever.

Conclusion: Families with young infants should be counseled to keep their babies away from cigarette smoke or individuals with colds or presumed viral illnesses.