Reuters
British scientists on Monday launched a trial which will deliberately expose participants who have already had COVID-19 to the coronavirus again to examine immune responses and see if people get reinfected. In February, Britain became the first country in the world to give the go-ahead for so-called "challenge trials" in humans, in which volunteers are deliberately exposed to COVID-19 to advance research into the disease caused by the coronavirus. "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 Helen McShane, a University of Oxford vaccinologist and chief investigator on the study.