While coughing and sniffling students are not an abnormal sight on Georgetown University’s campus during the winter, this year’s flu season has drawn national attention. Nationwide, doctor visits for influenza among children have reached their highest level in a decade, sparking questions about whether this year’s outbreak is unusually severe.
Much of the early concern stemmed from public health surveillance data and reporting from health agencies, which indicated that the influenza virus had continued to mutate after this season’s vaccine was selected. Each year, flu vaccines are selected months in advance based on global surveillance data to allow time for manufacturing. Because influenza viruses continue to mutate, the strains circulating during flu season can differ from those included in the vaccine.
Dr. Juan Gea-Banacloche, an infectious disease specialist at MedStar Georgetown University Hospital, said that this year’s flu season likely appears worse due to routine changes in circulating virus strains.
“From time to time, what happens is that there is variation in the virus between the moment you choose the strains for the vaccine and the moment the season begins, and that has happened this year,” Gea-Banacloche told The Hoya.
Gea-Banacloche also said such changes are a known feature of influenza biology.
“There has been drift in the influenza virus,” Gea-Banacloche said. “It has acquired a number of mutations, making it significantly different from the virus that was included in the vaccine.”
Still, Gea-Banacloche said this year’s vaccine still offers meaningful protection, particularly against severe outcomes, according to data from the United Kingdom.
“The data from the U.K. show the vaccine is a little bit worse than other years at preventing hospitalization and severe disease, but not incredibly so,” Gea-Banacloche said. “The protection against severe disease and hospitalization is between 40 and 60 percent higher in children than in adults, which is pretty good.”
In the United States, surveillance data tracked by the Centers for Disease Control and Prevention (CDC) classify this season as “moderately severe,” based on indicators such as outpatient visits, hospitalizations and geographic spread.
One aspect of this season that has stood out is the unusually high number of flu cases in children. Influenza complications typically pose the greatest risk to older adults, making the increase in younger people notable.
On Georgetown’s campus, students have noticed more illness circulating this winter. Evana Moses (CAS ’29), a neurobiology major, said the increase aligns with her sense that this year’s vaccine may not match the dominant strain.
“I definitely think this is one of those years where the flu shot just predicted the strain wrong,” Moses told The Hoya. “The strain that’s going around isn’t one that’s included in the vaccine, so that might be why people are getting more sick.”
Moses said that belief influenced her personal decision not to receive the flu shot this season.
“I did not consider getting the flu shot, and it’s because they kind of predict the strain of the flu every year,” Moses said. “Sometimes they get it right and sometimes they don’t, so more often than not, even if you get the flu shot, you can still get the flu that’s going around. So I didn’t see the point.”
However, Moses added that her decision does not reflect opposition to vaccines more broadly.
“I literally have like every other vaccine you can think of,” Moses said. “Sometimes some years I get it, some years I don’t.”
Other students said the vaccine’s imperfect match did not outweigh its potential benefits. Ryan Nero (CAS ’29), a biology major, said he typically gets the flu shot because he sees little downside to taking the precaution.
“For me, getting the flu shot isn’t that big of a deal because I haven’t had to deal with any side effects,” Nero wrote to The Hoya. “If I can help decrease my chances of getting one of the strains of the flu, that’s better than being vulnerable to it and makes it worth the time to go get the shot.”
Gea-Banacloche said that declining vaccination rates nationally may help explain this season’s trends, particularly among children. Recent analyses indicate that flu vaccination coverage has fallen compared with past seasons.
“If that decline is more pronounced among children, that may explain what we’re seeing,” Gea-Banacloche said.
With college students living in close quarters, prevention strategies remain especially important, experts say. Moses said minimizing spread in shared spaces is important.
“I think it’s important to not be embarrassed to wear a mask, even though it’s not COVID anymore,” Moses said. “If you’re sick, just stick to your dorm as much as you can and try your best and be respectful of other people.”
Despite heightened attention, Gea-Banacloche said the current data does not suggest a historic shift.
“In all honesty, to my eye, it doesn’t even seem like an outlier,” he said. “With the information we have right now, this looks like just the usual flu, maybe a little bit worse.”
