Researchers debated how rigorously to test Covid-19 vaccine candidates at a public meeting Thursday of the FDA’s advisory committee on vaccines.

“Simply preventing mild cases is not enough and may not justify the risks associated with vaccination,” said Peter Doshi, an associate professor at the University of Maryland School of Pharmacy, who detailed his concerns in an editorial in The BMJ.

But vaccine experts say there are good reasons to focus on milder cases of Covid-19.

Vaccines that prevent mild disease typically prevent severe disease, as well, said Dr. Arnold Monto, an epidemiologist at the University of Michigan’s School of Public Health and temporary chair of the vaccine committee.