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Strep throat

  • A potentially serious bacterial infection that causes pain and inflammation in the throat
  • The main symptom is throat pain, but it also can cause difficulty swallowing, fever, other symptoms
  • Treatment is a full course of antibiotics, typically penicillin or amoxycillin
  • Involves pediatrics, general pediatric otolaryngology

Strep throat


Sore throats can be caused by many types of bacteria, viruses and allergies, but strep throat—most common in children between ages 5 and 15—has its own tell-tale signs. Caused by the group A streptococcus bacteria, strep throat is an infection that requires prompt treatment, particularly in children over the age of 3.

Left untreated, strep throat can lead to kidney inflammation or rheumatic fever, a serious illness that can cause stroke and permanent damage to the heart. Fortunately, strep throat can be easily diagnosed with a simple throat culture, and promptly treated with a course of antibiotics.

At Yale Medicine, our pediatricians are skilled at diagnosing and treating strep throat, including being able to identify the rare cases that demand a higher level of care, says Maryellen Flaherty-Hewitt, MD, a Yale Medicine pediatrician. “If it isn’t a straight-forward case, we have pediatric experts in infectious diseases and ear, nose and throat physicians to call upon,” she says.

What is strep throat?

Strep throat is an infection caused by group A streptococcus bacteria (also known as streptococcus pyogenes) that leads to pain and inflammation in the throat.

Most sore throats are caused by viral infections and are accompanied by a runny nose, cough and other upper-respiratory complaints. These symptoms typically clear up on their own without antibiotic treatment.

Strep, however, does not typically include upper-respiratory symptoms and, in children age three and older, does require antibiotics in order to prevent serious complications.

What are the symptoms of strep throat in children?

The hallmark symptom of strep throat is pain in the throat that develops quickly and lasts throughout the day. Swallowing foods and liquids may be especially uncomfortable.

Other signs and symptoms, which typically appear two to five days after coming in contact with the germ, include:

  • Headache
  • Nausea, sometimes with vomiting, or general tummy ache 
  • Swollen glands
  • Red throat
  • Bad breath
  • White patches or streaks of pus on the tonsils
  • Fever that begins suddenly and is often highest on the second day
  • Rash that starts on the neck and chest and spreads across whole body
  • Loss of appetite

Deciding which child needs a throat swab to test for strep is a judgment call based on certain criteria, and Dr. Flaherty-Hewitt says she looks for particular symptoms as red flags.

“It’s hard when kids come in complaining of a sore throat, because it could be from a cold, or allergies, or the change of the season,” she notes. “But if they have mostly upper respiratory infection symptoms, we know it’s less likely to be strep. With strep, there is often no cough or respiratory symptoms. They are more likely to have a headache, nausea or just that their tummy feels a little off. Fever and swollen glands are other important considerations when considering strep throat.”

If your child develops a rash of red bumps that feels like sandpaper, that means strep has advanced to scarlet fever, also known as scarlatina. Scarlet fever is treated with the same line of antibiotics as strep but, since it means the infection has progressed, requires immediate attention. 

How does strep throat spread?

Highly contagious, strep throat is spread through airborne droplets (sneezing, coughing, sharing food, drink or utensils). Children can also get infected by touching surfaces that carry the bacteria and then touching their nose, mouth or eyes.

“I often tell parents not to share anything in the house that goes in the mouth,” says Dr. Flaherty-Hewitt, who is medical director of Yale New Haven Hospital’s Pediatric Primary Care Center. “Once they have been on antibiotics for 24 to 48 hours, they shouldn’t be contagious. We also advise throwing out their toothbrush and washing their pillowcases or other such items after they have been on the antibiotics 24 to 48 hours.”

As for prevention, practicing proper hand hygiene is key. “Wash your hands and cover your mouth with your elbow when you cough or sneeze,” Dr. Flaherty-Hewitt advises. 

How is strep throat diagnosed?

After performing a physical exam of your child and discussing his or her symptoms, your child’s physician will likely perform what is called a rapid antigen test. This entails using a swab to obtain a sample from the back of your child’s throat.

The test can detect strep bacteria in just a few minutes. But if it comes back negative, a culture will be sent to a laboratory for more in-depth testing that rules out false negatives. Those results come back in one to two days.

“My little trick is that I tell my patients I am going to tickle their tongue,” Dr. Flaherty-Hewitt says of her method of obtaining a culture from reluctant children. “That generally works, at least the first time they come in and they open up wide enough to get a good sample from their tonsils.”

How is strep throat treated in children?

If your child’s test comes back positive for strep, antibiotic treatment is required. The medication helps prevent rare—but serious—complications, including rheumatic fever.

However, for children under the age of 2 or 3, rates of rheumatic fever are much lower than for older children, Dr. Flaherty-Hewitt notes. “We consider the diagnosis of strep pharyngitis less often in this age group because the risk of rheumatic fever is much less”.

Penicillin or amoxicillin are typically the first antibiotics a doctor will try, usually for a course of ten days. Other antibiotics may be used, as needed.

“Within 48 hours of starting their antibiotic, children are feeling much better, but parents need to remember to complete the full course of antibiotics even when their children start to improve,” says Dr. Flaherty-Hewitt.

For comfort, she recommends plenty to drink, ice pops, pudding, applesauce, and other soft foods. “Many parents worry about their kids if they have strep and aren’t eating, but that’s OK,” she says. “We are more concerned about liquids and that they are properly hydrated.” 

What are the risk factors for strep throat?

“Although adults get strep throat, too, it is most common in children from the preschool age up through middle school, into the teenage years,” says Dr. Flaherty-Hewitt.

Sometimes, children are carriers of the bacteria. They may not be sick, because the bacteria grows slowly, but they can infect others in the family. “For possible carriers, we don’t want to keep randomly swabbing them and putting them on antibiotics,” explains Dr. Flaherty-Hewitt. “If we suspect a child is a carrier, we have them come in for a test when they are completely well. If they are a carrier, we can potentially treat them for good with a combination of different antibiotics. Because we know that some children may be carriers, we try to use some guidelines in testing children appropriately, and not get a rapid strep or lab culture for every sore throat that we see.”

Season is another risk factor for strep throat. Though it can strike at any time of year, strep is far more common in late fall and early spring, and among groups of people in close proximity, such as school settings. “It definitely comes in waves,” Dr. Flaherty-Hewitt says.

What are possible complications of strep throat?

Although rare, complications of strep throat may include:

  • Inflammation of the kidneys
  • Scarlet fever
  • Rheumatic fever
  • Abscesses near the tonsils

Recurrent strep throat can sometimes mean children need to have their tonsils removed (called a tonsillectomy). Yale Medicine Pediatric Otolaryngology (ear, nose and throat) surgeons offer several advanced treatment options for this. 

What stands out about Yale Medicine’s approach to strep throat?

As an academic medical center, Yale Medicine offers access to highly trained and experienced pediatric specialists, including surgeons specializing in treating children with ear, nose and throat problems. These specialists are at the top of their respective fields in advanced treatment methods and clinical research.

Also, Yale Medicine is one of the few places where surgeons can offer partial tonsillectomy, which can mean a quicker and less painful recovery for children who are appropriate candidates.