Cary, N.C. — Strep throat is a very contagious and potentially serious illness that is often dismissed as nothing more than a sore throat. But letting the illness run its course can be dangerous, so it's important to know what to look for and when to see a doctor.

Dr. Scott McGeary has seen a lot of patients with respiratory illnesses lately at Accent Urgent Care in Cary. He said  the difference between viral sore throat and strep, which is a contagious bacterial infection, are significant. Strep typically does not include cold symptoms like coughing and congestion.

"When someone wakes up with an intensely sore throat, has fever, has headache, (and) they've got swollen glands, then the likelihood of it being strep certainly increases," McGeary said.

Getting treated for strep is crucial to preventing other problems, such as kidney complications, rheumatic fever or an abcess in the tonsils that could require surgery, doctors say.

When patients describe severe sore throat symptoms, doctors will typically order a rapid strep test, which is about 90 percent reliable. If the test is negative but the symptoms point to strep, doctors will likely order a throat culture test, which takes a couple days for a result.

Once strep is diagnosed, antibiotics are the most common treatment. Adults and children should wait 24 hours before returning to school or work after beginning a course of antibiotics.