A bill for $476 for inquiring about participating in a medical research study? This is no joke.

Children have suffered both physical and mental illness during the pandemic. Nearly 200 children in the United States have died. Acute mental health crises increased during the pandemic. Getting children immunized is the best way to get back to normal. We suggest an option that would permit children under 5 to be vaccinated without waiting until traditional prospective randomized trials can be completed.

In late May, an international organization eliminated a 40-year prohibition against human embryo research beyond 14 days. The legal and scientific consequences will vary around the world.

In an essay published in Scientific American, we call for immediate and intensive research into the possibility that exposure to one of the coronaviruses that cause the common cold could decrease the severity of Covid-19, and could be leveraged to expand what’s been called “pre-existing” immunity to the disease by deliberate transmission of common cold coronaviruses. Here, we expand on our proposal.

As multiple Covid vaccine candidates enter clinical trials and hopefully move closer to approval, one important unanswered question is how to compensate the rare cases of serious vaccine harm.

The Covid-19 pandemic is unlikely to end until there is a safe, effective, and widely distributed vaccine. How soon can researchers achieve this goal? The answer largely depends on which strategies researchers are willing to adopt. One potential strategy is to conduct human challenge studies, in which researchers give an experimental vaccine to healthy volunteers and then test—or “challenge”—the vaccine by purposely exposing volunteers to the virus. Although a growing number of voices are calling on researchers to employ this strategy, the proposal is generating a heated debate about the ethics of such research.

Experts in infectious disease and public health warn that the Covid-19 pandemic will be with us until there is an effective vaccine, possibly 12 to 18 months in the future. This situation has given rise to calls for human challenge studies, in which healthy volunteers are injected with an experimental vaccine and then infected with the disease to test the vaccine’s efficacy. Is this ethically justifiable?