CDC says RSV on rise in Florida and Southeast

Cases of respiratory syncytial virus, or RSV, are on the rise in Florida and parts of the Southeast, the Centers for Disease Control and Prevention warned in a health advisory Tuesday.

The advisory is aimed at putting doctors, especially pediatricians, on notice that Florida is likely headed into another RSV season.

Across Florida, there has been an increase in the number of admissions for RSV and more positive tests for the virus, according to a weekly report in Florida’s sentinel surveillance system. It shows that cases of the illness are increasing in 23 Florida counties, including Hillsborough, Manatee and Hardee.

And local hospitals, including Johns Hopkins All Children’s Hospital and those run by BayCare, are seeing an uptick in cases compared to two months ago, although the increase is only moderate at this point.

The virus spread widely in the fall of 2022 after two years when COVID restrictions like social distancing and masking threw off the usual infection cycles for RSV and influenza.

“This is a little bit earlier than a typical RSV season,” said Juan Dumois, a pediatric infectious diseases physician at All Children’s. “The pandemic changed RSV epidemiology and demonstrated how much infectious diseases like RSV depend upon human behavior.”

RSV is an infection of the lungs and respiratory tract. Symptoms are similar to a common cold with low-grade fever, sore throat and congestion or a runny nose, according to the Mayo Clinic.

But it can cause more serious lower respiratory tract diseases such as pneumonia and bronchiolitis in infants 12 months and younger, older adults, people with heart and lung disease and those with a weak immune system. Infants who were born prematurely are especially vulnerable to the infection. About 14,000 adults 65 and older die each year from the disease, according to the National Institute of Allergy and Infectious Diseases.

The uptick comes at a time when there are several new prevention options to combat the virus.

Nirsevimab, a monoclonal antibody also known as Beyfortus, was approved in July by the Food and Drug Administration to protect infants and some young children. In clinical trials, one dose administered as an intramuscular injection reduced the risk of severe RSV by 80% over a fivemonth period, roughly the length of an RSV season, according to the CDC advisory.

It is recommended for infants younger than 8 months and for infants between 8 and 19 months who are at increased risk from RSV.

There are also two vaccines recommended for adults over 60 who have asthma or other respiratory conditions that put them at increased risk of ending up in the hospital if infected.

And on Aug. 21, the FDA approved Abrysvo, a vaccine developed by Pfizer that expectant mothers can get between weeks 32 and 36 of their pregnancy to give their baby protection against severe RSV for its first six months. The vaccine takes advantage of the natural process that occurs in the final trimester when the mother’s antibodies are shared with their baby through the placenta.