Fever in children younger than three months of age. A pooled analysis.

Concern that febrile infants younger than 3 months of age are at high risk of serious infection has prompted a management policy of routine hospitalization with antibiotic administration. Ten published studies of febrile infants younger than 3 months of age were reviewed, and data were statistically combined to develop estimates of the risk of bacteremia and serious infection. Factors that predicted increased risk were similarly evaluated. Mean and median risk estimates included, respectively, 3.0 and 3.4 percent for bacteremia, 1.3 and 1.0 percent for septic meningitis, and 5.0 and 7.0 percent for pneumonia. These were no higher than comparable estimates for older infants. Clinical appearance was 92 percent sensitive in predicting bacteremia in 500 infants (23 of 25 cases). Younger age, higher fever, and elevated white blood cell count were associated with increased risk of serious infection. Data from these studies do not support the belief that febrile infants younger than 3 months are uniformly at greater risk of serious infection than older infants. Judicious evaluation of younger infants could lead to more selective, cost-efficient management.