If you buy something through a link on this page, we may earn a small commission. How this works. Strep throat is a bacterial infection that causes inflammation and pain in the throat. This common condition is caused by group A Streptococcus bacteria.

But how do you know what strain you have? Although most symptoms, like sore throat and painful swallowing, are similar across strains, understanding the different forms of strep and what they can lead to can mean better relief, faster. Group A strep, the most common strain that primarily affects children and young adults, is a bacterial infection that causes a sore, scratchy throat. It is not uncommon for the symptoms of strep throat, such as fever, painful swallowing and throat pain, to be caused by a viral infection or other illnesses.

Worried your sore throat may be strep throat? Doctors can do a quick test to see if a sore throat is strep throat. If so, antibiotics can help you feel better faster and prevent spreading it to others. Viruses are the most common cause of a sore throat. However, strep throat is an infection in the throat and tonsils caused by bacteria called group A Streptococcus group A strep.