Would you sign up to catch a deadly disease and live in isolation for weeks? These friends did

On an overcast afternoon in Halifax, Amy Mullin has wrapped up her remote workday — filled with emails and video calls — and is getting ready for yet another night alone.

She's going to do virtual yoga with her friend Tato Crisanto and maybe a distanced movie night, with the pair planning to hit "play" at the same time on their respective laptops.

During this time of being stuck inside 24/7, all by herself, Mullin says she feels like a bit of a hypochondriac.

"I sneezed two times in succession, and I was kind of like — oh no — is it starting?"

That isolation and anxiety might feel overly familiar, but Mullin isn't talking about catching COVID-19 or enduring a lockdown in early 2020.

Instead, after years of restrictions and rapid tests and far too many Zoom calls, Mullin and Crisanto both signed up for several weeks alone in separate hospital rooms, all for the sake of science.

The friends are among dozens of Canadians participating in a human challenge trial — a type of medical study that involves purposely infecting people with a particular pathogen. In this case, it's the bacteria Bordetella pertussis, known for causing potentially deadly whooping cough.

The study, more than a decade in the making, is one of the first of its kind in Canada. It's run by the Canadian Center for Vaccinology (CCfV) inside an airlocked hospital unit at Halifax's IWK Health Centre, which features 10 isolation rooms equipped to control infectious agents like pertussis.

The research team's goal? Better understanding the progression of whooping cough, which affects between 1,000 and 3,000 Canadians each year, in hopes of eventually developing an improved vaccine.

"These types of studies have been done for over 70 years," said Dr. Scott Halperin, director of the CCfV, "but there has really been a re-emergence of them because of the number of things that one can learn."

Human challenge trials made headlines during the COVID-19 pandemic as researchers used the approach to study the progression of SARS-CoV-2 infections.

They've also been used to research diseases from cholera to malaria, and earlier this year, one participant in a trial to study dysentery — an illness known for causing painful stomach cramps and bloody diarrhea — went viral for live tweeting his unpleasant experience.

Not surprisingly, the approach can be controversial — scientists are infecting people on purpose, after all — and there are plenty of hoops researchers need to jump through.

"In order to make this type of study ethical, the pathogen has to be one that is not going to cause, or unlikely to cause, severe disease or death," Halperin says.