Several children's hospitals in the U.S. have detected increases in invasive group A strep infections, a severe and sometimes life-threatening illness that occurs when bacteria spread to areas of the body that are normally germ-free, such as the bloodstream.
Children's hospitals in Arizona, Colorado, Texas and Washington told NBC News they are seeing higher-than-average numbers of cases this season compared to past years.
Two young children in the Denver metro area have died since Nov. 1, according to Colorado's public health department. Eleven cases of severe or invasive strep infections in children up to 6 years old have been identified in the Denver area in that time, the department added. In a typical year, Denver sees one or two such pediatric cases per month.
Dr. James Versalovic, the pathologist-in-chief at Texas Children’s Hospital in Houston, said his facility — the largest pediatric hospital in the U.S. — has seen "a greater than fourfold increase" in potentially invasive infections in the last two months compared to the same period last year.
Texas Children’s recorded around 60 cases in October and November, he said.
In the U.K., at least 15 children have died from invasive group A strep since mid-September. The U.K. Health Security Agency said in an advisory last week that cases tend to rise sharply in the new year but appear to have spiked earlier than expected.
The World Health Organization said Thursday that France, Ireland, the Netherlands and Sweden are seeing cases increase as well, but that the risk to the general population is low.
The Centers for Disease Control and Prevention, meanwhile, said it is “hearing anecdotes from some U.S. doctors of a possible increase in [invasive group A strep] infections among children in the United States” and is “talking with surveillance sites and hospitals in multiple states to learn more.”
Group A streptococci are the same bacteria that cause strep throat, as well as skin conditions like scarlet fever (a red rash that feels like sandpaper and can resemble a sunburn) and impetigo (red, itchy sores with yellow scabs).
Some people with invasive strep A may develop those conditions, as well, but in many cases the first sign is a secondary infection, like pneumonia or flesh-eating disease.
“These are cases beyond an ordinary strep throat,” Versalovic said.
An invasive infection can trigger the following:
- Lower airway infections like pneumonia or empyema, which are characterized by pockets of pus in the fluid-filled space surrounding the lungs. Early signs of such infections include fever, chills, difficulty breathing or chest pain.
- Skin infections like cellulitis or necrotizing fasciitis, also known as flesh-eating disease. Both conditions involve red, warm, swollen or painful rashes. Necrotizing fasciitis spreads quickly and can turn into ulcers, blisters or black spots.
- Streptococcal toxic shock syndrome, an immune reaction that can lead to organ failure. The condition often begins with fever, chills, muscle aches, nausea or vomiting and then causes rapid heart rate or breathing.
Anyone can get invasive strep A, including healthy adults, but people over 65 and those with chronic illnesses are more susceptible. It is not yet clear why hospitals are seeing an uptick in cases among kids in particular. The CDC said it may be related to the rollback of Covid mitigation measures and the surge of respiratory viruses like flu, Covid and RSV.
“Oftentimes, kids who develop severe group A strep infections will start out with having a viral respiratory infection,” said Dr. Sam Dominguez, an infectious disease specialist at Children’s Hospital Colorado and a professor at the University of Colorado School of Medicine.
The Colorado health department said many of the recent cases in Denver also had a recent viral respiratory illness.
The U.S. records several million cases of noninvasive group A strep every year, but invasive infections are rare, at around 14,000 to 25,000 cases annually, according to the CDC. Between 1,500 and 2,300 people die of the invasive infections every year.
The CDC said it observed decreases in such infections across all age groups during the last two years.
In the U.K., the last comparable spike in case numbers was from 2017 to 2018, when 27 children died.
At Phoenix Children’s Hospital, case numbers have been rising since the end of October or early November, said Dr. Wassim Ballan, the division chief of infectious diseases. But he said the condition is uncommon compared to RSV or flu.
“Even though we’re seeing that this is an uptick in cases, the absolute number itself is not huge," Ballan said.
Unlike RSV and flu, which tend to pose the most serious threats to very young children, doctors said they're treating kids of all ages for invasive group A strep right now.
“We’ve had teenagers, younger kids, kind of the whole range," said Dr. Sara Vora, an infectious disease expert at Seattle Children’s.
“We had a fairly sick teenager last week who came in with kind of a sepsis presentation and was in the ICU on a ventilator for a few days and then had a fairly rapid recovery and is doing very well," Vora added. "That’s probably the most severe case that I have seen.”
But children’s hospitals in several other states — California, New York, Illinois and Minnesota — said they have not detected any increase in invasive group A strep.
Parents worried about their children's health should consider seeking emergency medical attention if their children are sleepier or more lethargic than normal, have trouble eating or drinking or are overly dehydrated and not producing urine, Dominguez said.
Vora suggested that as a general rule, "if your kiddo is not acting right, seems to have symptoms that are worse than just an average cold or lasting longer than a couple of days, then it’s worth having them checked out."
It is important for kids with strep to get care right away so they can start taking antibiotics like penicillin. After 24 hours on antibiotics, a patient usually stops being contagious.
“The sooner you get someone on antibiotics appropriately, the quicker they’ll recover,” Dominguez said.
CORRECTION (Dec. 15, 2022, 11:00 a.m. ET): A previous version of this article misspelled the name of a lower airway infection. It is empyema, not emphysema.