... That the communities hardest hit by Covid-19 have also been woefully underrepresented in clinical trials is no coincidence, and in racing to find 30,000 participants who could represent an even broader population, pharma companies have found themselves face to face with health care’s deepest fault lines. Being Black, Latinx, Native American, or Pacific Islander, for instance, means you are more likely to go without health insurance than if you’re white, and that makes a difference. If you want people to sign up as test subjects for experimental vaccines, it helps if they feel comfortable going to a hospital — and are able to take sick leave.

... In emphasizing the need for diversity in these studies, vaccine makers have tried to put their money where their mouth is. The Pfizer-BioNTech team proposed expanding the number of participants in their trial from 30,000 to around 44,000, “to further increase trial population diversity.”

... For those who are even less at ease in a clinic or hospital, the worries often run even deeper. The federal government’s involvement in vaccine development makes some would-be participants — many of whom are not U.S. citizens — worry that they may not have control over who gets to see their data, and that that might affect their immigration status, explained Maldonado, the CEO of the Chicano Federation.

... The focus on underserved communities is closely tied to the fact that many among them are frontline workers — more likely, by the nature of their jobs, to be exposed to the coronavirus. Yet the logistics can be tough if your employer doesn’t allow you the flexibility that would allow you take time to visit a clinic for injections and follow-ups.