Pharyngitis is common in children, accounting for nearly 12 million visits annually in the United States. Streptococcus pyogenes or group A streptococcus (GAS) is the most common bacterial cause of pharyngitis for which antibiotics are indicated.
Antibiotic treatment of streptococcal pharyngitis virtually eliminates the presence of bacteria from the pharynx and thus removes the risk of subsequent rheumatic fever.
GAS is spread from person to person via respiratory droplets with a short incubation period of 2∼5 days.
GAS pharyngitis peaks in the late winter and early spring months when children are predominately indoors for school and sports.
Colonization is also higher in winter months, and while up to 20% of school age children are colonized with GAS in their throat during this time, colonization has not been shown to contribute to the spread of disease.
In low- and middle-income countries and other situations in which crowding is common (e.g., schools), outbreaks of pharyngitis are common.
GAS pharyngitis can occur at all ages and it is most common in school-aged children with a peak at 7∼8 years of age.
Pharyngitis caused by GAS is rare in children <3 years of age and becomes much less common in late adolescence through adulthood.