Jun 30, 2020
Vaccine challenge trials, in which healthy volunteers are infected with a pathogen to determine whether a vaccine works, can be done faster and with fewer participants than traditional efficacy studies. But there are downsides: challenge trials require young, healthy participants which may not help produce a vaccine that would protect older populations at risk for severe COVID-19 disease. There are also serious ethical considerations. Volunteers would be infected with a virus for which there is no cure, and so much is still unknown about why this coronavirus can cause severe disease in people without any known risk factors. Johns Hopkins vaccine researcher Dr. Anna Durbin talks with Stephanie Desmon about this method of getting to a COVID-19 vaccine, her experience with a dengue challenge trial, and what we know so far about whether COVID-19 antibodies confer immunity.