A U.K. study is looking to see the effects of COVID-19 on people who have been either previously exposed to the virus through infection or vaccination, and it will pay a hefty sum to those who participate in the research trial.

Researchers from the University of Oxford are seeking a number of volunteers to be purposely exposed to a COVID-19 pathogen. This pathogen may obviously make study volunteers sick and comes with some risks, but researchers maintain it is a way for them to study the body’s immune response to the virus and could help to improve COVID vaccines.

Helen McShane, professor of vaccinology at the Department of Paediatrics, University of Oxford, and chief investigator on the study, said: “A human challenge model is where, under very carefully controlled conditions, we deliberately expose healthy volunteers to a bug or pathogen.

“The aim of this trial is to find out what level of immune response - antibodies and T cells - we need in our bodies to prevent infection when healthy people are exposed to the virus. This is the immune response we then need to induce with a new vaccine.”

The study, which began in April 2021, first infected 50% of participants with a low dose of the virus to produce infection with little to no symptoms.

The study, which is in phase two, is working with young, healthy adults aged 18 to 30. Using droplets that are inserted up the nose, the study aims to infect all participants with a standardized dose of the virus.

The study’s research team has been working to develop the minimum dose of the virus that would be needed to induce an immune response.

“We have learned a lot about COVID over the past two years, but the emergence of new variants means that we will probably have to keep refining the vaccines,” McShane said. “If we know what level of immune response we need the vaccine to induce, it will make future vaccine development much quicker and much more efficient.”

The strain of the virus studied is the original COVID virus from Wuhan, China.

Volunteers that participate in the study will need to quarantine in a specially designed hospital suite for a minimum of 17 days under the care of the research team. Here, they will undergo a series of medical tests that will include CT scans of the lungs and MRI scans of the heart.

Participants who develop symptoms from their COVID infection will be treated with a Regeneron monoclonal antibody treatment known as Ronapreve.

The study will last for 12 months, with at least five follow-up visits required after discharge.

Payment for the full study participants is at least £4,995, or about $6,681.

A man undergoes a rapid Covid-19 test at a medical van in New York on December 17, 2021 A man undergoes a rapid COVID-19 test at a medical van in New York on Dec. 17, 2021. Photo: AFP / Ed JONES