Robust public health evidence should concede multifactorial causation

The recent controversy surrounding Covishield vaccine and its rare side effects reported by AstraZeneca raises an important ethical question in public health practice. Public health ethics has not been perceived as distinct from medical ethics and by default, evidence in medicine is at times interpreted as being the same as public health evidence, when the context of practice of the two disciplines is distinct. There is a tendency in public health practice to opt for those interventions with maximum benefit to the maximum number, guided by utilitarian ethics, whereas in medical ethics the focus is on benefits vs risks. It is important to examine whether the side effects of any public health intervention can be justified against the risk it can pose to even a single healthy individual?