Population-based prevalence of repeated group A β-hemolytic streptococcal pharyngitis episodes

OBJECTIVE: To define the population-based 3-year period prevalence of repeated group A β-hemelytic streptococcal (GABHS) pharyngitis episodes in children between 4 and 15 years of age. PATIENTS AND METHODS: Residents of Rochester, Minn (age, 4-15 years), who had 3 or more GABHS pharyngitis episodes in 1 year, at least 1 month apart, between January 1, 1996, and December 31, 1998, were identified using the resources of the Rochester Epidemiology Project (N=536). Pharyngitis episodes (evidence of a sore threat with or without presence of fever) followed by either a positive rapid streptococcus test result or a positive plate culture test result were considered positive GABHS episodes. Age- and sex-specific prevalence rates were calculated, assuming that all residents 4 to 15 years of age in Rochester during 1396 to 1993 were at risk. RESULTS: A total of 203 children met our definition for repeated GABHS episodes between 1996 and 1998 and were included in this study. Approximately 1% of children between the ages of 4 and 15 years experienced repeated GABHS pharyngitis episodes between 1996 and 1993. This estimate increased to approximately 2% among children 4 to 6 years of age and decreased to 0.1% among children 13 to 15 years old. CONCLUSION: A relatively small proportion (1%) of children between 4 and 15 years of age experienced repeated GABHS episodes in a 3-year period; however, this proportion represents a substantial number of children who are affected at the population level. Given the increased costs associated with treating repeated GABHS episodes, further studies are necessary to determine how best to reduce episodes and treatment costs in this age group.