They deliberately infected volunteers with Covid.

The Download Your daily dose of what's up in emerging technology Infectiousness insights 02.03.22

Hello! Today: insights have started trickling in from the first study to deliberately infect people with covid—we break down the most significant findings. Get your friends to sign up here to get The Download every day. What researchers learned from deliberately giving people covid   The news: People who’ve caught covid become infectious far more quickly than previously believed, according to the world’s first “human challenge trial” study in which healthy young volunteers were deliberately infected with the virus. The study, carried out by a team led by researchers at Imperial College London, is the first to watch what happens from the moment someone is infected with SARS-CoV-2. The findings: The 36 volunteers, all aged 18-30, were exposed to a low dose of the original SARS-CoV-2 virus in the nose. Half of the participants developed covid symptoms, and became infectious within just two days, with levels of infectious virus peaking at five days. It has previously been estimated that it took about five days from exposure to first symptoms. Participants in the study remained infectious for an average of nine days. What it all means: The findings come with the caveat that they’ve been derived from a small pool of volunteers. However, they provide useful insights nonetheless. The fact that people become infectious so quickly and stay infectious for so long suggests that recommended isolation periods should be kept at around ten days. Although the virus was detected in the throat first, it was eventually present at much greater levels in the nose, highlighting the need to wear face masks properly. The research also supports the regular, widespread use of lateral flow testing. And the fact that the challenge trial was carried out safely also suggests that this approach could help test future vaccines, variants or treatments.