Fever in the First Six Months of Life

Abstract

The age-specific rate of elevated temperature over 37.8 C was evaluated in all infants less than 6 months of age (n = 1341) seen from July 1, 1974 to June 30, 1978 in a family practice clinic. Mild elevations (37.8 C-38.3 C) were common even in the first few months of life, and accounted for 20.7 per cent of infant visits. Temperatures greater than 38.3 C are uncommon in the first months of life but are seen more frequently with each succeeding month. Temperature elevation over 38.3 C was associated with a significantly higher rate of meningi tis (p < .01), otitis media (p < .001) and lower respiratory infection (p < .05). Significantly higher laboratory usage was documented in infants less than 3 months and for infants with temperature more than 38.3 C. The high rate of mild temperature elevations in young infants suggests that a selective diag nostic strategy directed at high-risk infants is important. Infants less than three months of age with a fever exceeding 38.3 C are calculated to have 21.5 times the risk of a serious underlying infection as infants older than three months with a similar temperature elevation. Clinical evaluation must remain an important tool in determining which febrile infants should be evaluated by further laboratory and diagnostic tests.