The existing framework for testing, approving, and regulating vaccines does not consider that vaccines have broad effects on the immune system that may alter the risk of unrelated infections.

It is now clear that vaccines can have important non-specific effects that can sometimes be very beneficial and sometimes harmful. In current practice, this can go unnoticed.

We propose a new framework for testing, approving, and regulating vaccines, with phase III trials, which should collect data on all symptoms arising during the follow-up, and with phase IV trials designed to assess vaccine effects on overall health.