Researchers Deliberately Infected People With COVID—Here's What They Learned

Key TakeawaysChallenge studies intentionally infect participants under very strict regulations to observe the full lifecycle of a virus.A U.K.-based study purposely infected 36 volunteers with COVID-19.Researchers gained insight into how the virus works in younger, healthy adults.

Key Takeaways

Challenge studies intentionally infect participants under very strict regulations to observe the full lifecycle of a virus.A U.K.-based study purposely infected 36 volunteers with COVID-19.Researchers gained insight into how the virus works in younger, healthy adults.

With great risk comes great reward—at least that’s what researchers were betting on when they began a COVID-19 challenge trial this year.

Challenge trials are studies where participants are intentionally infected with a virus or other pathogen. Scientists value challenge studies because of the opportunity to study infection from its origin. By doing so, researchers can observe details that might otherwise be missed.

Catherine Gregor, Chief Clinical Trial Officer atFlorence Healthcare, shared that challenge studies are not a new idea and have been used throughout medical history.

Why a COVID-19 Challenge Trial Is So Controversial

“This type of study is not new,” Gregor told Verywell via email. “It has been used throughout history to help researchers better understand how different viruses affect the body, going all the way back to the first smallpox experiments. What has changed over time is the rigor and regulatory requirements associated with clinical trials. Challenge studies and first in human studies are much more tightly controlled in today’s environment which in practice makes them safer for participants.”

Insight Into the Virus

Since there are so many ethical concerns with challenge studies, the study was small, with only 36 participants chosen out of 26,000 volunteers. Among those exposed to the virus, only 18 developed COVID-19. Gregor said that this could be the subject of further study to investigate what biological factors may have protected some from infection.

Among those infected, researchers observed that the infection began extremely quickly—within two days of first exposure. Prior estimates of infection times ranged from five to six days from exposure.

Why Diversity Matters In COVID-19 Vaccine Trials

While the virus was initially detected in the throat, despite the sample virus being administered through drops in the nose, it built the strongest colonies of virus in the nose. Scientists say that this indicates that the virus is much more likely to be spread through the nose, making proper mask-wearing essential to curbing virus transmission.

Of the 18 infected participants, only 13 of them lost their sense of smell, which has been considered one of the most reliable predictors of COVID-19 infection. All but three participants regained their sense of smell within three months.

What This Means For YouWhile controversial, the challenge study gave researchers an interesting look at how the virus affects younger, healthy people. It also further proved that properly worn masks can mitigate the spread of the virus since the viral load was most concentrated in the nose.

What This Means For You

While controversial, the challenge study gave researchers an interesting look at how the virus affects younger, healthy people. It also further proved that properly worn masks can mitigate the spread of the virus since the viral load was most concentrated in the nose.

Continuing Research

While researchers have released their initial findings, they will continue to follow all the participants in the study for the next 12 months to observe any further developments.

Gregor said that this small study could be a blueprint for expanded research in the future.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit ourcoronavirus news page.

1 SourceVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Killingley B, Mann A, Kalinova M, et al.Safety, tolerability and viral kinetics during SARS-CoV-2 human challenge.Research Square. Preprint posted online February 1, 2022. doi:10.21203/rs.3.rs-1121993/v1

1 Source

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Killingley B, Mann A, Kalinova M, et al.Safety, tolerability and viral kinetics during SARS-CoV-2 human challenge.Research Square. Preprint posted online February 1, 2022. doi:10.21203/rs.3.rs-1121993/v1

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Killingley B, Mann A, Kalinova M, et al.Safety, tolerability and viral kinetics during SARS-CoV-2 human challenge.Research Square. Preprint posted online February 1, 2022. doi:10.21203/rs.3.rs-1121993/v1

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