Group A streptococci among school-aged children: clinical characteristics and the carrier state

This study reports on the incidence of GAS infection in 64 US children aged between 5 and 15 years, who had throat swabs routinely collected twice a month, and whenever they had symptoms or signs of pharyngitis, during a four-year period (1998-2002). Episodes of new streptococcal throat infection occurred at a rate of 25-35% per year. Approximately 50% of episodes of new infection were symptomatic. The mean duration of carriage following a new infection was almost one year.