This nemesis came roaring back after the pandemic

After dropping to low levels during the COVID-19 pandemic, strep throat came roaring back this winter and spring to exceed the number of cases in the years immediately preceding the pandemic. Cases of less common, but more dangerous, invasive group A Streptococcus infections followed a similar pattern, according to the Centers for Disease Control and Prevention.

“We have seen a lot more strep,” said Emergency Physician Kinsey M. Leonard, DO, a member of the team of physicians that works in Cape Cod Hospital’s Emergency Department. She also works at two of Cape Cod Healthcare’s Urgent Care Centers in Hyannis and Harwich.

Most cases of strep throat occur in children ages 5-15, but this year Dr. Leonard has treated cases in both younger siblings and older adults, who are often grandparents or other people in close contact with children.

While she does not have specific numbers of cases on Cape Cod, “we’ve seen a rise in general and there has been an equal increase nationwide of invasive group A when compared to prior years,” she said.

According to an April 19 paper by Epic Research, cases of strep throat in the United States, along with RSV, flu and other respiratory infections, plummeted in March 2020 and stayed low until September 2022. However, by February 2023 cases of strep throat rose to be 30 percent higher than the most recent peak in February 2017, three years before the onset of the pandemic. The increase was seen in all areas of the nation and all age groups, although children accounted for most infections, the article said.

Symptoms, Diagnosis and Treatment

Strep throat is caused by group A Streptococcus bacteria. It’s very contagious and spreads by droplets in the air from an infected person, touching something with those droplets on it, or eating or drinking from a utensil or glass used by an infected person, according to the CDC. Symptoms start two to five days after exposure. Some people have an infection but no symptoms, and are carriers that can spread illness, though they’re less contagious than people with the pain and fever of strep throat.

Children or adults should come in for a rapid strep test if they have a high fever and a red throat with white patches or areas of pus on the tonsils, Dr. Leonard said. Symptoms can include swollen cervical lymph nodes in the front of the neck and small red spots called petechiae on the roof of the mouth, the CDC says. A test can help determine if a sore throat is caused by strep or something else, such as COVID-19, she said.

The result from the rapid test takes about 10 minutes and is about 95 percent accurate, Dr. Leonard said. Growing a culture from a throat swab is still the gold standard, she added, and takes about 48 hours. If a rapid test comes back negative, but all the symptoms match with strep throat, Dr. Leonard said she generally starts treatment without waiting for culture results. Treatment is usually with the antibiotic amoxicillin, but a doctor may order a comparable antibiotic, as amoxicillin shortages are occurring, according to the CDC.

Treatment with antibiotics isn’t always needed.

“Some people can get better on their own,” Dr. Leonard said, however treatment can “help limit duration, transmission, and complications.”

Complications and Invasive Group A Strep

It’s more important for kids to be treated, as strep throat can spread to cause ear infections, become scarlet fever or result in kidney problems, she said. Scarlet fever and strep throat both have symptoms for a red, very sore throat, fever of 101 degrees or higher, chills, body aches and headaches, and may also include nausea and vomiting. Coughing isn’t a standard symptom and may indicate a viral infection. Scarlet fever is distinguished by a red, sandpapery rash that may start in the underarms, groin or neck and spread over the body.

Some patients develop serious complications after a bout with strep throat, scarlet fever or impetigo, a group A strep infection of the skin, including:

• Inflammation of the kidneys called post-streptococcal glomerulonephritis (PSGN) that in rare cases may cause long-term damage or kidney failure.
• Inflammation of the heart and joints called rheumatic fever that can cause painful joints, symptoms of congestive heart failure and sometimes enlargement of the heart, fluid buildup around the heart or a heart murmur.

Neither condition is a strep infection but are thought to result from the body’s immune reaction to a preceding strep infection, according to the CDC.

When group A strep infects a part of the body that normally doesn’t contain bacteria, it’s called invasive group A strep, or iGAS, and it causes severe illness usually requiring in-hospital care and may be fatal, the CDC says. These illnesses include necrotizing fasciitis and toxic shock syndrome.

“Invasive group A strep, there has been a rise in that, as well,” Dr. Leonard said. “If it gets in the bloodstream, it’s called bacteremia.”

So far this year, preliminary data indicates iGAS infections have stayed at elevated levels in some areas of the country after cases of seasonal viral respiratory infections (colds, flu, RSV) dropped off, according to the CDC. IGAS infections in adults, especially those 65 and older, have risen in some areas.

Dr. Leonard said the explosion of contagious respiratory infections following the end of pandemic restrictions of social distancing and wearing masks likely contributed to a high amount of strep throat cases.

“If you were wearing a mask the last two years, you weren’t exposed to anything,” she said. “Now we’re seeing, my gosh, so much RSV. If you get RSV, it lowers your immunity,” making it easier to catch strep throat.