What is this “RSV” I’ve been hearing about?

Infectious Diseases

RSV (respiratory syncytial virus infection) is one of the dozens of viruses that can cause “the common cold.

But it’s one to watch out for: it’s highly contagious and unlike some of the other common cold causes, RSV can turn dangerous. Preemies, infants, young children; people with immune, lung, or heart disease; and older adults are at risk. And RSV is having a *moment* in the Northern hemisphere right now.

There are TONS of colds going around right now. Without being sick enough to go to the doctor, it’s hard to know if you have RSV or some other junk. But if you or your kids are sick, it wise to avoid interaction with grandparents or high risk individuals just in case. Though RSV is very often thought of as a kids’ health problem, it causes more than 150,000 hospitalizations and 14,000 deaths among *older* adults in a typical season.

RSV is normally a seasonal virus with an epidemic curve that gets going in mid-September just after kids go back to school. The seasonality is likely driven by its transmission mode: RSV is spread by snotty fingers touching shared surfaces and by coughing and sneezing in shared indoor air. In fact, by age 2, nearly all children will have had RSV at least once, and half of children will have already had it twice. RSV infection doesn’t produce good immune memory, so we can get it again and again. Each time we get it our immunity builds a little bit, so older children and healthy adults get less severe disease on their 5th, 6th, 12th, or 40th go with RSV.

So far it is shaping up to be a bad RSV season. This could be “catch-up” from periods of low transmission when COVID-19 precautions were high. RSV is something all people get eventually, so if you have a toddler who has never had it, you’re overdue.

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RSV causes a lot of serious illness every year and is the leading cause of infant hospitalizations in the US. The virus infects the lower lungs, where it may lead to severe complications like pneumonia (infection in the lungs) and bronchiolitis (inflammation of the ti y airways in the lungs). RSV normally causes more than 2 million doctor’s visits in kids under age 5 and 100-300 deaths in this age group. Combined with persistent COVID-19 and an early flu season, RSV is part of the “tripledemic” that is causing severe hospital strain and what some doctors are calling the worst pediatric care crisis in decades (see link below).

Symptoms of RSV appear 4-6 days after you’ve been exposed, and usually include: runny nose, decreased appetite, coughing, sneezing, fever, and wheezing. These symptoms usually appear in stages, so it’s like every day is a new adventure in feeling cruddy for about a week. In newborns, the only symptoms may be irritability and breathing difficulties. In kids, it’s usually a runny nose and decreased appetite followed by a cough a few days later. In adults, it is often indistinguishable from any other cold.

The prevention of RSV is old-fashioned: keep your hands clean and avoid close contact with people who are sick. In this case, “close contact” means kissing, shaking hands, and sharing cups and eating utensils. While there was less focus on airborne transmission of RSV prior to COVID, it’s likely that a lot of the same measures for avoiding sharing air that work for COVID (ventilation, masks) will also help reduce transmission of RSV– and the flu.

If you have symptoms of “the common cold,” avoid contact with people who are high-risk like newborns, preemies, people with compromised immune systems, and people who have chronic lung or heart disease. You’re no longer contagious within about a week of symptoms appearing.

Scientists have been working on a vaccine for RSV for decades, so far without success. However, more recently, the tremendous burden of RSV and improved understanding of the disease process has sparked renewed interest, and there are now 4 new promising RSV vaccines nearing review by the US FDA.

🤞It’s even *possible* we might have an approved RSV vaccine before next fall.

Remember that of the viruses filling up pediatric hospitals right now, we DO have vaccines (down to 6 months) for influenza and COVID-19. If your child hasn’t received these vaccines now is a great time.

Let’s keep fighting this “tripledemic” with the tools we have!

Stay safe, stay well.

Those Nerdy Girls


Additional Links:

“The worst pediatric-care crisis in decades” by Katherine Wu

US Trends in RSV from CDC

CDC explainer: Respiratory Syncytial Virus Infection (RSV)

Link to original Those Nerdy Girls Facebook post