People walk on a street, as the coronavirus disease restrictions ease, in London, Britain April 12, 2021. — Reuters picLONDON, April 19 — British scientists today 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.
The study launched today differs from the one announced in February as it 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. She added that the work would help understanding of what immune responses protect against reinfection.
The first stage of the trial will seek to establish the lowest dose of the coronavirus needed in order for it to start replicating in about 50 per cent of participants, while producing few to no symptoms. A second phase, starting in the summer, will infect different volunteers with that standard dose.