Discussions on whether or not vaccination is a benefit to the public are often associated with how the risk of a particular vaccination program is communicated. Risk of vaccination is generally communicated to the public from so-called experts within the vaccination debate. Scientists involved in the research of these vaccines, efficacy testing and clinical trials are frequently required to explain their findings and give advice to government and regulatory bodies, such as the Therapeutic Goods Administration within Australia and the Federal Drug Administration in the US. It is these groups that make the decision, based on how they perceive the risk, as to how to communicate this risk to the public. In general, I would imagine that these groups would consider risk from a utilitarian perspective where any disadvantage that may affect a minority of the population can be justified by the much greater advantage to the majority of the population. These groups would look at the risk with respect to the regret rule of risk analysis which is similar to the utilitarian ethical approach, where the risk of not vaccinating could lead to many more deaths and spreading of disease is far greater that the risk associated with the act of vaccination causing illness or death.
Hansonn S.O., Ethical criteria of risk acceptance, ERKENNTNIS 59(3): 291–309