02/08/2022

What Researchers Learned From Deliberately Giving People COVID-19

The trial provided insights into the infection's progress

The news: People who have caught covid become infectious far more quickly than previously believed, according to the world’s first "human challenge" 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 (COVID-19/coronavirus).

The findings: The 36 volunteers, all aged 18 to 30, were exposed to a low dose of the original virus in the nose, the equivalent of the amount found in just a single drop of nasal fluid. Half the participants developed covid symptoms; they became infectious within just two days, with levels of infectious virus peaking at five days. It has previously been estimated that the time from exposure to first symptoms was about five days. Participants in the study remained infectious for an average of nine days and still had detectable levels of virus in their nose 12 days after initial exposure.

Almost all the volunteers lost their sense of smell and experienced cold-like symptoms such as a runny nose and sore throat. None reported serious symptoms. Some of the patients were also given the antiviral drug remdesivir before they were infected, but the trial didn't pick up any noticeable difference in the severity of the symptoms.

Please select this link to read the complete article from MIT Technology Review.