In 1545, a smallpox epidemic hit India, presumably introduced by Portuguese colonizers, and killed 8,000 children in Goa. Paris was affected by a pertussis (whooping cough) epidemic in 1578. In the 16th and 17th century, smallpox was imported to North America by European colonizers. Smallpox had devastating effects on the native population across the colonial America. It killed many French Jesuits and Native Americans in Canada in 1625, as well as a large number of English settlers and Native Americans in Massachusetts in 1633.
Yellow fever spread epidemically in Cuba, Barbados, and the Yucatan, so Boston established a strict quarantine for ships from the West Indies in 1648. Nine years later, measles appeared in the city for the first time. In 1659, symptoms most likely pertaining to diphtheria were described as “bladders in the windpipe.” Around the same time, Chinese Emperor K’ang encouraged inoculation against smallpox among his subjects after he had survived the disease (his father Emperor Fu-lin had died of smallpox).
In 1667, English physician Thomas Sydenham published an article documenting details about measles and differentiating it from smallpox and scarlet fever. In 1678, a medical pamphlet on smallpox was published in response to the epidemic in New England. In 1684, Sydenham observed that the rich seemed to have a higher mortality rate from smallpox than the poor. He concluded that the medical treatments of the time, such as bloodletting from the tongue, might be rather harmful since they were only accessible for the rich. Queen Mary of England the II died of a severe case of smallpox in 1694.
In 1699, yellow fever broke out in the North American colonies, killing vast numbers of people. Boston minister Cotton Maher discovered in 1706 that an African Slave named Onesimus had a scar from a smallpox variolation and found that many slaves had been variolated and thought to be immune against the disease. Thus, Maher read up about variolation in English journals and promoted the practice in Massachusetts. In 1718, Lady Mary Montagu, wife of the British Ambassador to Turkey (who was disfigured by smallpox) had her son variolated in Turkey, where it was common, and endorsed the procedure back in England. In 1721, variolation was officially introduced in the American colonies as smallpox raged across the continent.
The practice was controversial as 2 – 3% of variolated people died of smallpox (in comparison to 15 – 40% who would die naturally of the disease). The 1730s saw devastating epidemics of smallpox, yellow fever and diphtheria. In 1740, German physician Friedrich Hoffmann identified “German measles,” rubella. Scottish physician Francis Home discovered that the measles virus is present in blood. Meanwhile, inoculation against smallpox became increasingly popular, though English farmer Benjamin Jesty already used cowpox to inoculate his wife and sons in 1774. Smallpox was also used as a weapon of war in 1776, which lead to mandatory inoculation of the Continental Army a year later.