Pediatrician Caroline Marcus, M.D., explains how you can tell if you child’s sore throat is strep throat: Page ContentStrep throat is common among people of all ages, although it’s most prevalent between ages 5 and 15. Because symptoms are similar to other illnesses, the only way to know for certain if your daughter has strep throat is for a doctor to exam her. Besides throat pain, common signs and symptoms of strep throat include:Red and swollen tonsils, sometimes with white patches or streaks of pus.Tiny red spots at the back of roof of the mouth.Swollen, tender lymph nodes in the neck.Fever, headache and fatigue.A rash.Strep throat is caused by highly contagious bacteria known as streptococcus pyogenes or group A streptococcus. It spreads through airborne droplets when someone with the infection coughs or sneezes or by touching a doorknob or other surface and transferring them to your nose, mouth or eyes.Untreated, strep throat may lead to such complications as kidney inflammation and rheumatic fever. Rheumatic fever may result in painful, inflamed joints, a rash and damaged heart valves. Strep throat is diagnosed by a physical exam and lab tests. A throat culture may be performed, which involves swiping a sterile swab over the back of the throat and tonsils to obtain a sample of secretions.If your child has strep throat, her doctor will likely prescribe an oral antibiotic and may suggest over-the-counter medications to help relieve throat pain and reduce fever.