Massachusetts smallpox epidemic
The Massachusetts smallpox epidemic or colonial epidemic was a smallpox outbreak that hit Massachusetts in 1633. Smallpox outbreaks were not confined to 1633 however, and occurred nearly every ten years. Smallpox was caused by two different types of variola viruses: variola major and variola minor. The disease was hypothesized to be transmitted due to an increase in the immigration of European settlers to the region who brought Old World smallpox aboard their ships.