UK researchers have started a trial which will deliberately expose participants who have already had COVID-19 to the virus again to examine immune responses and see how many get reinfected.

The study launched on Monday seeks to reinfect people who have previously had COVID-19 in an effort to deepen understanding about immunity, rather than infecting people for the first time.

“The information from this work will allow us to design better vaccines and treatments, and also to understand if people are protected after having COVID, and for how long,” said Professor Helen McShane, a University of Oxford vaccinologist and chief investigator on the study.

She added that the work would help understanding of what immune responses protect against reinfection.