Why RSV is On the Rise

What parents should know about the summer uptick in respiratory virus cases among children.

A common winter virus, respiratory syncytial virus, or RSV, has been on the rise this summer, particularly in the Southern United States , with hospitals reporting more infant hospitalizations and sick children than is normal for this time of year. According to the Centers for Disease Control and Prevention (CDC), there were about 1,700 confirmed cases in the U.S. during the week of July 24, 2021, compared to fewer than a dozen during the week of July 25, 2020.

“RSV infection generally happens in the fall, winter, and spring, when cold and flu season is more prevalent,” says Dr. Hossein Sadeghi, pediatric pulmonologist and director of the Sue and John L. Weinberg Cystic Fibrosis Center at NewYork-Presbyterian Morgan Stanley Children’s Hospital. “But this hasn’t been a typical year with the COVID-19 pandemic.”

Dr. Hossein Sadgehi

Dr. Hossein Sadeghi

So why are we experiencing a summer surge of RSV? To understand, Health Matters spoke with Dr. Sadeghi, who is also an associate professor of pediatrics at Columbia University Vagelos College of Physicians and Surgeons, to explain what RSV is, who it affects, how serious it can be, and why the sudden increase in cases.

If RSV cases are more common in the fall and winter months, why the sudden uptick this summer?
If we look back at the past 12 months, people were wearing face masks, practicing good hand hygiene, and were isolating themselves to control the spread of COVID-19. In doing so, that drastically reduced the rate of other viral infections, like RSV. But now, with COVID-19 vaccinations leading people to forgo face masks and the easing of travel restrictions, there is more transmission of viruses.

Who does RSV affect?
RSV can affect anyone, but it most seriously affects premature infants or those with underlying risk factors. Most children experience a case of RSV by the time they are 2 years old. But that was pre-pandemic. With all the infection control of the past year, that may not hold true.

Is it dangerous?
For most people, it can present like a cold and usually clears up with plenty of rest and fluids. But for anyone with a weakened immune system, they are more at risk of developing severe symptoms. For example, those who are born premature (less than 29 weeks of gestation), those who are 65 years or older, and anyone with chronic lung disease or neuromuscular weakness, RSV can affect them much more severely.

Generally speaking, the really young and the really old are more at risk of developing severe symptoms.

Why is RSV dangerous for infants?
RSV is more dangerous in babies because their immune system is still developing. In babies, RSV can cause bronchiolitis (inflammation in the small airways of the lungs), pneumonia, or croup, which can lead to breathing difficulties and a persistent cough. For premature babies, they could end up in the intensive care unit.

What are the warning signs?
If a parent sees that their baby is working harder to breathe — they are wheezing, have nasal flaring, or belly breathing (you can see their ribs when they breathe in and out) — these are signs that they might be struggling to breathe. Another important clue in infants is reduced feeding. If your baby isn’t eating as much, that could be an initial sign that something could be wrong.

Contact your pediatrician if your child is at risk of severe RSV infection, has irritability, decreased activity, apnea (pauses in respiration), difficulty breathing, fever that is over 101 degrees, blue color lips, or reduced feeding.

How can you tell the difference between RSV and COVID-19?
Because RSV symptoms are so similar to COVID-19 — cough, congestion or runny nose, fever — it can be difficult to tell the difference without a PCR test. If you or your child is experiencing any of those symptoms, talk with your doctor about getting tested for RSV and COVID.

How do you treat RSV at home?
Get plenty of rest and fluids. There currently is no vaccine for RSV, but most infections will go away on their own within a week or two. Parents can help relieve fevers with an over-the-counter fever reducer and pain reliever like acetaminophen or ibuprofen. (Do not give aspirin to a child.) For high-risk infants, talk with their pediatrician about palivizumab (Synagis), a monoclonal antibody — an immune system protein — which can be given to high-risk infants every 28 to 35 days during the RSV season, November through March.

What can parents do to keep kids safe?
Taking preventive measures is key, especially for those who are at higher risk like premature babies or children with chronic lung disease. RSV can stay on hard surfaces for up to six hours, so handwashing and regularly disinfecting high-touch surfaces like doorknobs, countertops, and sinks are very important.

If you have an older child who goes to school or day care, I recommend changing their clothes as soon as they get home, washing their hands, and maybe even giving them a bath to reduce the risk of RSV transmission to a younger sibling.

Avoid close contact with anyone who is sick, and, of course, for any infection that we have vaccinations for — like the flu and COVID — it’s important to immunize those who are eligible. The best defense against COVID-19 is vaccination. And when flu season starts, it’s important to get the flu vaccine as well.

Hopefully the COVID pandemic has taught us to take better care of ourselves by practicing good hand hygiene and infection control measures, getting enough rest, adequate nutrition, and regular exercise. All of these things can help optimize our immune system and keep us healthy.

Hossein Sadeghi, M.D., is a board-certified pediatric pulmonologist and sleep medicine specialist with extensive experience in cystic fibrosis, asthma, and global health. He is the director of the Sue and John L. Weinberg Cystic Fibrosis Center at NewYork-Presbyterian Morgan Stanley Children’s Hospital. An associate professor of pediatrics at Columbia University Vagelos College of Physicians and Surgeons, he focuses his research on asthma, RSV bronchiolitis, and cystic fibrosis.