Koplik spots (gray–white papules on the buccal mucosa) may be seen during this prodromal phase. Approximately 3–4 days after the prodromal symptoms, the typical exanthem of coalescing ...

In the early 1950s there were four vaccines routinely used in the United States: diphtheria, tetanus, pertussis, and smallpox. Three of these vaccines (diphtheria, tetanus, and pertussis) were ...