The respiratory virus season has started early in kids this year and flooded children's hospitals in many parts of the country -- especially with respiratory syncytial virus, known as RSV.
But adults can get RSV, too. Although RSV does not typically send as many adults to the hospital, it can be a serious and even deadly disease for seniors and people with underlying health conditions.
And with more kids getting RSV, the chances that adults will be exposed also rise. Some doctors say they are starting to see an uptick in adult patients.
This season, about 6 out of every 100,000 seniors has been hospitalized with RSV, according to data from the US Centers for Disease Control and Prevention. That's significantly lower than the rate for children but still uncharacteristically high. In the years before the Covid-19 pandemic, hospitalization rates for seniors were about 10 times lower at this point in the season.
Dr. Ann Falsey, a professor of infectious diseases at the University of Rochester Medical Center who has published research on RSV in adults, said RSV rose somewhat in children in the summer and early fall last year, but the US did not see the usual proportional increase in RSV in older adults at the time.
"I think that older adults were more cautious to continue public health measures like masks and social distance last year because they were still worrying about Covid," Falsey said. "But this year, we're starting to see older people ending up in the hospital again with RSV, because everyone is throwing caution to the wind."
Virus flies under the radar in adults
Too often, RSV flies under the radar in adults, she said. Many people, even doctors, overlook its impact on adults.
"They think of it as strictly a pediatric disease, but you know, if you don't test for it, you'll never know what somebody actually is sick with," Falsey said.
In the United States, tracking viruses like RSV isn't nearly as thorough as it is for Covid-19, so it is difficult to know exactly how many adults get sick with RSV. The numbers of RSV cases come from self reports that go to a few dozen labs that only represent about a tenth of the population, and reports are then shared with the CDC.
Based on best estimates, there are between 10,000 and 15,000 adult deaths in the United States from RSV each year and around 150,000 hospitalizations for RSV, Falsey said.
A 2015 study of older adults in industrialized countries said the disease burden of RSV is "substantial" and calculated that about 14.5% of the 1.5 million adults who caught RSV were admitted to hospitals. People who were 65 and older were more likely to be hospitalized than those ages 50 to 64.
"When we compare it to influenza A, it's not too far behind," Falsey said, referring to one of the strains of seasonal flu that's often linked with more severe illness.
RSV symptoms in adults
RSV shows up in adults the same way it does in kids. It can look like a common cold and include runny nose, decreased appetite, coughing, sneezing, fever and wheezing. The symptoms typically last a week or two, and they clear up with rest and fluids.
But in some adults, RSV can become dangerous because it can lead to dehydration, breathing trouble and more serious illnesses such as pneumonia and bronchiolitis, inflammation of the tiny airways in the lungs.
Adults at risk for severe illness from RSV
The adults who are most seriously at risk for severe outcomes with RSV are those 65 and older. The virus can spread quickly through a nursing home or long-term care facility, just like Covid-19 and flu.
Adults with weakened immune systems need to be careful in RSV season. This can include people undergoing treatment for cancer, transplant patients, people with HIV and those who take certain drugs that suppress the immune system for diseases like Crohn's, lupus or rheumatoid arthritis.
Adults with chronic heart or lung disease like asthma, COPD or heart failure are also more likely to have to go to the hospital if they catch RSV.
How RSV spreads
An infected person can pass on RSV through a cough or sneeze. If the respiratory droplets land on a surface like a doorknob or desk and someone else touches it and then touches their face, they can get sick.
It also spreads because healthy adults often won't know they have it. It doesn't typically cause fatigue like the flu or Covid does, so many adults will go to work or jump on a plane or bus, chalking up their symptoms to allergies. As they interact with others, it spreads further.
RSV can easily spread from children to adults, too.
What do you do if you get RSV
If you have been coughing or have any other RSV-like symptoms and you are in a high-risk category, you should go to your doctor and get it checked out, says Dr. Daphne-Dominique Villanueva.
"We can't test everybody right now -- in an ideal world we would want to do that -- but we want to concentrate on vulnerable people," said Villanueva, an assistant professor in the School of Medicine at West Virginia University who has written studies about RSV.
Doctors' offices have swab tests that can determine whether an illness is flu, RSV or Covid.
There are specific antivirals for flu and Covid-19 but not for RSV. The trick is getting tested early, even to rule out RSV; getting started on Covid or flu antivirals right away can shorten the time you are sick and keep the virus from progressing to something more serious.
With RSV, the treatment is what's called supportive care: Drink plenty of fluids. Get some real rest. Stay home so you don't spread it. Wear a mask around others in your home.
If you start to wheeze and feel short of breath, Falsey said, those would be clear signals that you should see a doctor or maybe even take yourself to an emergency room quickly. At the hospital, they can give you supplemental oxygen if necessary.
Protection from RSV
There's no protection from a vaccine for RSV, but that could change by next season. In the US, there are four RSV vaccines that may be nearing review by the FDA, and more than a dozen are going through trials. Some are designed to protect infants, and some are being tested in older adults.
"Since we have very limited ways of treating it effectively, you should do whatever you can to prevent getting it in the first place," Villanueva said.
Protective measures for this busy RSV season will sound familiar: Wash your hands frequently, disinfect surfaces, and wear a mask in crowded spaces.
"You might want to put off that visit for a week to see your grandkids, or you might want to wear a mask if you are going into a crowded place," Falsey said. "Masks and hand-washing work. I know people are kind of over it, but if you're a frail person or you know you have underlying medical conditions, when we know that RSV is surging, you should do those things and use caution around children who are actively sick. It all helps."
™ & © 2022 Cable News Network, Inc., a Warner Bros. Discovery Company. All rights reserved.