Out of isolation: RSV and croup cases spike among Louisville children

After  a year of isolation because of COVID-19, children's immunities to infections like respiratory syncytial virus (RSV) and croup may be lower, leading to an atypical season of both. 

The U.S. Centers for Disease Control and Prevention issued a health advisory on June 10 saying that despite low numbers of RSV in 2020, numbers are on the rise since late March in Southern states including Kentucky, Alabama, Florida and others. 

Meanwhile, Norton Healthcare's hospitals, pediatric offices and immediate care centers reported 296 cases of croup in April 2021, compared with 22 in April 2020 — a 1,200% increase. The system also reported a 2,600% increase in May 2021 compared with May 2020 — 464 compared to 17. 

RSV cases also rose dramatically. The system reported 22 RSV cases in April 2021 compared to seven in April 2020, a 214% increase. In May 2021, there were 26 cases, compared to four in May the previous year, a 550% increase. 

May saw seven RSV and 11 croup hospitalizations in Norton's hospitals. 

"Out in the community we're hearing more stories of children coming down with cold-like symptoms, more so than in ... past months when people were still wearing masks and socially distancing and so on," said Dr. Scott Bickel, a pulmonologist at Norton Children's and an assistant professor of pediatrics at the University of Louisville's School of Medicine. "That's translated into a increase in the rate of hospitalization for children." 

That's not normal for this time of year. RSV and croup are usually seen more in the fall and winter, but Bickel said it's unclear if the spike now will replace a 2021 fall season. 

"I think once ... society kind of shifts back into ... more normal activity, I suspect this fall ... we will probably ... revert back to a more normal spike in respiratory viruses," he said. "It would be nice if seeing it now would delay it then, but I'm not sure that that will be the case." 

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Children with preexisting conditions like asthma, premature birth or congenital heart disease are at higher risk. RSV symptoms may include nasal drainage, congestion, wheezing, labored breathing, fever and dehydration. Croup symptoms can include a barking cough, a scratchy voice and some infected children "will make a high-pitched, squeaky noise when they breathe," according to Norton. 

"I certainly think that if you have a child who has underlying medical issues or who is born prematurely or is ... under six months ... those parents need to be vigilant," Bickel said, adding almost all children are exposed to RSV by the time they're 2 years old. "Most children are going to have ... mild to moderate cold-like symptoms and will recover within a week or two and ... not have the more severe manifestations ... that obviously are of concern."

A more serious complication of RSV is respiratory failure, for example. 

Parents should consult their child's pediatrician if symptoms occur, Bickel said, and some offices can test for COVID-19 and other viruses simultaneously. Natural ways to protect against these viruses include hand washing and avoiding large crowds and sick people. 

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Reach news reporter Sarah Ladd at sladd@courier-journal.com. Follow her on Twitter at @ladd_sarah.