Malaria in Batavia in the 18th century.

In 1733 an unknown deadly disease broke out in Batavia (now Jakarta), then the main seat of the Dutch East India Company (VOC) in Asia. Mortality among its personnel rose alarmingly and caused serious shortages of sailors, soldiers and craftsmen. Ever-growing numbers of people had to be sent from the Netherlands to Batavia to make up for the high losses. In the end, military posts could no longer be filled, homeward-bound vessels no longer be manned and precious cargo had to remain in Batavia. The unhealthiness of the town, 'so deadly for the growth and prosperity of the colony [and] ruinous for the interests and finances of the Company' (Nederburgh 1794), claimed more than 85,000 victims among VOC personnel. The 'unhealthiness of Batavia' remained unexplained through the ages. In this paper reasons for its origin and aftermath are proposed.