If it feels like there are multiple viruses floating around all at once, that’s because there are. With a seemingly new COVID variant every season, an unusually high number of RSV (respiratory syncytial virus) infections for this time of year, and flu season right around the corner, experts warn of a potential “tripledemic” this winter. But just how concerned should parents be?

“With regard to the ‘tripledemic,’ young children are the most vulnerable, and I’m seeing that in my practice right now,” says Dr. Mike Sevilla, a family physician based in Salem, Ore. “During the height of the pandemic, kids (and adults) have been shielded from illness with social distancing and with masking. However, as cases of flu, COVID, and RSV are on the rise nationally, we’re seeing more young children coming down with these illnesses here locally as well.”

However, Dr. Larry Kociolek, medical director of infection prevention and control and attending physician at Lurie Children’s Hospital of Chicago, is more concerned about the upcoming flu season than anything else.

“I think [influenza] has the potential to overwhelm our health care system,” he warns. “Unlike RSV, enterovirus—which is a group of infections that cause mild to serious illnesses—and COVID, we haven’t had an influenza season since early 2020. Influenza essentially went away for the last two and a half years, and so we have a huge population of infants—essentially almost every child in the U.S. who is under 2 and a half to 3 years old—who has not encountered influenza, and the vaccine rate is not particularly good.”

Thirty-nine pediatric deaths from influenza were reported for the 2021–22 season as of Sept. 24, 2022, according to the Centers for Disease Control and Prevention. In a typical year, doctors expect about 100 pediatric deaths from influenza in the U.S.; however, in a bad year, there could be several hundred. “I predict this will be a particularly bad year, unless we’re able to make great strides in our flu vaccine uptake over the next few months,” he says.

The best prevention of influenza and COVID is vaccination for both adults and of children, says Sevilla. The CDC recommends annual flu vaccines for everyone 6 months and older in the U.S. Typically the vaccine is given with a needle in the arm, but a nasal spray flu vaccine exists as well. Most people will only need one dose for the season, and it’s recommended you get vaccinated by the end of October for the most protection. The COVID vaccine is also recommended for protection against severe illness or death from the virus, although neither the flu shot nor the COVID vaccine are guaranteed to prevent the illnesses.

“When it comes to adults, I have been especially emphasizing to my high-risk medical patients, that vaccination is super important this year,” says Sevilla. “I understand that many Americans are experiencing pandemic fatigue, especially when it comes to social distancing and masking. However, when it comes to prevention, vaccination is the best step for protecting ourselves and our communities going into the fall and winter months.”

There is no vaccine for RSV yet, although there are two treatments available that can help infants and young children. RSV typically follows a seasonal pattern with cases rising in late fall and early winter, sometimes coinciding with flu season. Each year, approximately 58,000 children under 5 are hospitalized as a result of RSV infection, according to the CDC. And with the recent surge, many children’s hospitals are already at capacity.

“For an individual parent, the concern for each of these viruses is not different than it’s been in the past,” Sevilla says. “But as a health care system, we do need urgent solutions to [address] a surge of influenza at the same time as RSV or enterovirus….So we need people in the community to do as much as they can to keep themselves healthy with commonsense measures and vaccines.”

This story was originally featured on Fortune.com

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