This week, I joined a rapidly growing group of 14,183 people via the organization 1 Day Sooner in volunteering for human challenge trials (HCTs) to test promising vaccines against the novel coronavirus. If selected, I would be administered a vaccine candidate or a placebo then deliberately exposed to the SARS-CoV-2 coronavirus.

I did not sign up for this endeavor seeking heroism or notoriety, but because I weighed my own personal risks against the benefits to global society. In this calculation, there is an overwhelming net benefit. As a white, healthy, physically active 32-year-old with no underlying health conditions, my risk of death from COVID-19 could be as high as 1 in 1,200, but more likely as low as .014 percent, roughly 1 in 7,400. Participants in HCTs would be given small, controlled doses of virus and quarantined with excellent medical care, so that rate could be even lower. Still, we can estimate that if 20,000 people took part in HCTs, between two and seventeen participants could die.

In the absence of HCTs, thousands of participants would be given experimental vaccines or placebos in phase III trials then asked to go about their lives so they can potentially be exposed to the novel coronavirus. These trials last many months to ensure adequate infection numbers and sample sizes to ascertain efficacy.