Streptococcal pharyngitis in general practice. 1. Some unusual features of the epidemiology.

This report is based on a study of acute infections of the upper respiratory tract in 1965 and detailed records of such infections in 1963 and 1964. A change from illnesses mainly yielding viruses to illnesses mainly yielding group A streptococci was noted around the age of 5 years. A positive culture for group A streptococci in patients over 4 years of age was highly correlated with a complaint of sore throat and with serological evidence of streptococcal infection. A bimodal age distribution curve for pharyngitis associated with a positive culture for group A streptococci was consistently noted. The incidence was highest in children aged 5-9 but a second smaller peak occurred among adults in the 30-39 age group. The evidence suggests that being female increases the risk of acquiring group A streptococci and of experiencing sore throat.