SpaceX is preparing to carry four astronauts to a crowded International Space Station on Thursday, in the second routine mission since the United States resumed crewed space flight, and the first with a European.Chinese researchers are conducting a trial to see if mixing Covid-19 vaccines that use different technologies is safe and whether it could boost immunity.
“Various vaccine trials have been conducted in countries with a different Covid-19 status, at different times and on different study groups,” Lau said. “Different trials use different outcome measures for vaccine efficacy, so the safety and efficacy of various vaccines should not be casually linked.” Virologist Jin Dong-yan, from the same university’s medical school, supported research to see if mixing vaccines could improve efficacy and potentially “help to build up stronger herd immunity”.