Streptococcal pharyngitis

Streptococcal pharyngitis, also known as streptococcal sore throat (strep throat), is pharyngitis (an infection of the pharynx, the back of the throat) caused by Streptococcus pyogenes, a gram-positive, group A streptococcus. Common symptoms include fever, sore throat, red tonsils, and enlarged lymph nodes in the front of the neck. A headache and nausea or vomiting may also occur. Some develop a sandpaper-like rash which is known as scarlet fever. Symptoms typically begin one to three days after exposure and last seven to ten days.

Strep throat is spread by respiratory droplets from an infected person, spread by talking, coughing or sneezing, or by touching something that has droplets on it and then touching the mouth, nose, or eyes. It may be spread directly through touching infected sores. It may also be spread by contact with skin infected with group A strep. The diagnosis is made based on the results of a rapid antigen detection test or throat culture. Some people may carry the bacteria without symptoms.

Prevention is by frequent hand washing, and not sharing eating utensils. There is no vaccine for the disease. Treatment with antibiotics is only recommended in those with a confirmed diagnosis. Those infected should stay away from other people until fever is gone and for at least 12 hours after starting treatment. Pain can be treated with paracetamol (acetaminophen) and nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen.

Strep throat is a common bacterial infection in children. It is the cause of 15–40% of sore throats among children and 5–15% among adults. Cases are more common in late winter and early spring. Potential complications include rheumatic fever and peritonsillar abscess.