Reservations are once again open at St. Louis University's "Hotel Influenza," where amenities include furnished rooms, daily nasal swabs and a special HVAC system that keeps the viruses infecting each guest from escaping beyond the sealed facility.
This unusual arrangement is the university's Extended Stay Research Unit. Converted from a former hotel, the facility's 24 rooms are reserved for test subjects willing to be infected with the flu for 10 days in exchange for about $3,500.
"It's hard in a field study to really know when people are getting infected," said Dr. Daniel Hoft, who directs SLU's Vaccine Center. "For an immunologist such as myself, a vaccinologist trying to make vaccines, it's really important to know what's happening very early on after exposure to a virus."
Each participant will be infected with the influenza strain A H3N2 while under medical staff's care. None of the subjects will be recently vaccinated against the flu.
"We want to know that the people we're studying are only getting the flu that we give them, and not something else," Hoft continued. "So, 48 hours after we bring them into the unit, we are testing them every day. If they remain healthy and we don't see any evidence of an already incubating infection, then we go ahead and challenge them."
The challenge comes from exposure to the live flu virus. The upcoming study is only the second time the facility has been used since its debut in 2019; at the time, one of the 17 participants remarked that the hardest part of the process was enduring "a 6-inch Q-tip shoved up your nose," which "felt like they were touching your brain or trying to poke your eye out of your socket."
Despite the discomfort, Hoft said the participants will be helping scientists answer critical questions about how the flu affects the human body. Those insights will be applied to developing new vaccines. Hoft also noted that the study can provide evidence that a particular vaccine just isn't working as intended.
"We don't always know what the important immune responses [are] that we should target with new vaccines," he explained. "With a small number of people … you can [identify] certain vaccines that probably are not really going to help the world. By doing that, you don't waste time, you don't waste money, and you can get more quickly to the products that are most likely going to help you."
The study will have a wide selection of test subjects to choose from. The center's existing database of potential volunteers — some of whom were part of previous vaccine trials — stretches back 33 years and includes 18,000 names. Interested participants should contact the St. Louis University Center for Vaccine Development.
"We're most interested in bringing in people that are excited about the work, the science, the potential for doing good," Hoft said. "There's a lot of volunteers like that out in the community."
To hear the full interview with Dr. Daniel Hoft, SLU Vaccine Center director, including his insight into the center's work on the COVID vaccine, listen to St. Louis on the Air on Apple Podcasts, Spotify or YouTube, or click the play button below.
"St. Louis on the Air" brings you the stories of St. Louis and the people who live, work and create in our region. The show is produced by Miya Norfleet, Emily Woodbury, Danny Wicentowski, Elaine Cha and Alex Heuer. The audio engineer is Aaron Doerr. Send questions and comments about this story to talk@stlpr.org.
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