1、Current data are insufficient to define the incidence of adverse events in primary vaccinees as opposed to individuals re-vaccinated after a long interval.

2、Consistent adverse effects reported in smallpox vaccinees have been myopericarditis and dilated cardiomyopathy; the frequency of each adverse effect exceeds what might have occurred by coincidence.

3、An important safety issue related to the varicella vaccine is the impact on the epidemiology of herpes zoster both in vaccinees as well as in individuals previously infected with wild-type varicella.