Strep throat is an infection caused by a type of streptococcal bacteria. It is most common in children ages 2 to 10, but it can affect people of any age. Strep throat cannot be reliably diagnosed without a rapid strep test or throat culture.

If you have 3 or 4 of the following symptoms and do not have a cough, it is very likely that a bacterial strep throat is present:

• Fever of 101°F (38°C) or higher
• Pain that increases with swallowing
• Difficulty swallowing
• White or yellow spots or coating on the back of the throat and tonsils
• Swollen lymph nodes in the neck

Other symptoms of strep throat, especially in children, may include general body aches, headache, stomachache, nausea, vomiting, or listlessness. Strep throat usually doesn't occur with cold symptoms, such as sneezing, runny or stuffy nose, or cough. In general, the more coldlike symptoms you have, the less likely it is that your sore throat is caused by strep infection.

Most sore throats are caused by a virus and go away without medical treatment. However, sore throat is also a symptom of strep throat, a bacterial infection.

Strep throat with a rash is sometimes referred to as scarlet fever. The most noticeable symptom of scarlet fever is a rough, red rash that feels like sandpaper. This rash begins on the chest and abdomen and then spreads over the rest of the body within 24 hours. The rash and redness are more apparent in skin folds, especially in the groin, armpits, and elbow creases. Fever and a sore throat usually develop before the rash appears. The rash usually fades in about a week, and at that time the skin may begin to peel.

If strep throat is diagnosed, antibiotics are usually prescribed to help prevent rheumatic fever, which is a possible complication of untreated strep throat. Rheumatic fever can cause heart, joint, brain, and skin problems. Antibiotics are effective in preventing rheumatic fever if they are started within 9 days of the start of a sore throat.