Without such a trial, the appearance of efficacy may be an illusion, because other factors would have led to a lower rate of infection anyway. Yet if a promising vaccine is available – and if safety trials in healthy human volunteers who are not at risk of infection demonstrate that it does no harm – to deny it to those who are tending to the sick and dying, at great risk to their own health, seems unethical.
如果不进行这样的实验，效果就有可能只是幻觉，因为可能是其他因素导致了低传染率。但如果成功的疫苗可以获得&mdash;&mdash;并且以没有传染风险的健康志愿者为对象的安全性实验证明它没有危害&mdash;&mdash;那么不把它送到照顾患者和重症患者、自己也极有可能染上埃博拉的医护人员手中就是不道德的。