Strep throat is a contagious disease caused by infection with streptococcal bacteria. Strep throat symptoms generally include fever, sore throat, swollen lymph nodes in the neck and redness and swelling of the throat and tonsils. White or yellow patches on the tonsils (signifying pus) are also often present. Strep throat may produce mild or severe symptoms.
Strep throat is most common in school-aged children and teens, with a peak incidence between 5 to 15 years of age. It is estimated that approximately 15% to 40% of cases of sore throat in this age group are caused by Streptococcus spp bacteria. Adults may also develop strep throat, though less commonly (accounts for approximately 5% to 10% of cases of sore throat). Strep throat most commonly occurs between late fall and early spring. It is more widespread during the school year when groups of students are present within an enclosed space.
Though strep throat is the most common bacterial cause of sore throat, it is important to note that most cases of sore throat are in fact due to a viral infection (caused by a virus). A viral sore throat typically improves on its own and does not require treatment with antibiotics. However, the identification of strep throat is important to prevent the possible complications associated with this illness.