Sarah King isn’t afraid of having the flu — in fact, she considers herself an “excellent sick person.”

“I have a pretty high pain tolerance,” King said. “I'm not a person that whines a lot. I just kind of suck it up.”

When she heard about a medical study that pays volunteers about $3,000 to be infected with the flu virus, the marketing manager thought the offer sounded too good to pass up. Last month, she checked in for a 10-day stay at St. Louis University’s “Hotel Influenza,” a quarantine unit where researchers study how the human immune system fights the flu virus.

“My mom was not as jazzed about it,” said King, who lives in Webster Groves. “She said, ‘Oh, I’m so proud. You’ve grown up to become a lab rat.’”

After arriving at the quarantine unit in the university’s Salus Center, patients are exposed to the live flu virus through a nasal spray, said Dr. Daniel Hoft, a SLU professor of internal medicine and an infectious disease specialist.

“It's broken up into really tiny droplets to mimic what would happen when you breathe in microdroplets with influenza,” said Hoft, a study co-author.

None of the 17 patients has received a flu shot this year, Hoft said, because the research team wants to understand how the immune system naturally responds to the flu virus.

By sampling the immune cells and antibodies, the team hopes to learn whether certain immune responses suppress flu symptoms better than others — a finding that could help scientists develop more effective vaccines.

Credit St. Louis University A patient room at SLU's "Hotel Influenza." The university remodeled a floor of the Salus Center for the study and renovated the HVAC system to prevent the virus from being blown outdoors.

“We're also looking at what genes are switched on and off of the 35,000 genes we can detect now,” Hoft said. “This can help us discover new things that we never even thought about in terms of what's important for the immune response.”

The trial is part of a National Institutes of Health-sponsored study, with partner sites in Maryland, North Carolina and Ohio.

A vacation with strangers

True to its name, Hotel Influenza looks like a cross between a hospital and a budget motel. Each private room is furnished with a bed, a small desk and a sink.

A customized HVAC system keeps virus particles from escaping outside or recirculating to other floors of the building, while vinyl flooring makes for easy cleanup.

To keep from getting sick, the research team wore protective gear that looked like “spacesuits,” said study volunteer Matthew Meers.

“They wore face shields, aprons, gloves,” Meers said. “If I saw those nurses out in the open now, I wouldn’t be able to recognize them at all.”

Credit St. Louis University Azra Blazevica, assistant research professor at St. Louis University, prepares a nasopharyngeal swab sample for testing. The team collected blood and mucus samples from all patients throughout the study.

Meers took time off from his job as a grocery store meat department manager to participate in the study. He rarely gets the flu — and even after having the virus sprayed directly up his nose, he didn’t show any symptoms.

The most uncomfortable part of the study, he said, was the daily nasal swab.

“It was basically a 6-inch Q-tip shoved up your nose,” Meers said. “It felt like they were touching your brain or trying to poke your eye out of your socket. But you find little ways to get through it.”

At first, Meers took advantage of the unstructured time inside the flu hotel. He learned new card games, watched football and colored, he said, for the first time in decades. But after 10 days in quarantine, he started feeling antsy.

“I was getting stir-crazy,” Meers said. “I could feel my nerves getting jittery going through the final physical.”

Patients have to test negative for the virus for at least two days before being released. They leave the unit in a fresh set of clothing to reduce the risk of infecting the public.

For King, the marketing manager in Webster Groves, the quarantine unit offered a break from the “craziness of regular life.”

“There’s really no responsibilities in there,” King said. “I appreciated the simplicity, and I was a little hesitant to leave. It was a strange, twisted vacation.”

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