Strep throat is a bacterial infection that makes your throat feel extremely sore and scratchy, caused by bacteria called streptococcus. When you have strep throat, it hurts to swallow, your throat looks red and inflamed, and you might run a fever or feel exhausted. Unlike a regular sore throat from a cold, strep throat comes from specific bacteria that your body often needs help fighting off.

Doctors can test for strep throat by quickly swabbing the back of your throat. If the test comes back positive, they'll prescribe antibiotics, which are medicines that kill bacteria. With antibiotics, many people start feeling better within a day or two, and kids are often allowed to return to school after 24 hours of treatment. Without treatment, strep throat can last longer and occasionally lead to more serious problems.

Strep throat spreads easily through coughs, sneezes, and shared drinks, which is why it often moves through classrooms in winter and spring. If your throat hurts badly enough that eating becomes difficult, or if you see white patches on your tonsils, tell an adult so you can see a doctor. Regular sore throats from colds usually get better on their own, but strep throat needs medical attention.