Strep throat: How contagious is it?

Atalie Lim, MD, pediatrician with Dignity Health Medical Group — Inland Empire, shares how easily strep throat can spread, and how to minimize your risks of catching the bacterial infection.

How do I know if I have strep throat?“If you have a sore throat, it could be a viral infection like the common cold, or it could be a bacterial infection like strep throat. It can be hard to tell the difference, but to help you determine what you have, you can pay attention to your symptoms,” says Dr. Lim. “If you are unsure, you can visit your doctor who can perform a swab test.” 

Dr. Lim explains that common symptoms when you have a cold are a runny nose, sneezing and coughing. However, if you have strep throat, you are likely to have red tonsils, swollen neck glands, and pain with swallowing. With strep throat, you will typically not have a cough.

How contagious is strep throat?“Strep throat is very easily spread. You can become infected by respiratory droplets or direct contact with an infected person, like by sharing utensils,” says Dr. Lim. “Strep is most common in children ages 5 through 15.”

You can further prevent the spread of strep throat in your home by thoroughly cleaning and trying your best to isolate the infected person while they’re still contagious.

How long is strep throat contagious?“Strep throat is typically treated with antibiotics, and children may return to school after 12 hours of starting antibiotic therapy,” says Dr. Lim. “If untreated, the bacteriacan spread to other parts of your body. It can cause serious complications including kidney inflammation and heart problems.” 

If you suspect you may have strep throat, you can schedule an in-person or virtual appointment with your primary care physician. Our “Find a Doctor” tool can help you find a Dignity Health physician near you.