The water was badly contaminated and threatened a major epidemic.

During the colonial period, there were major epidemic outbreaks which led to the implementation of sanitary and preventive policy.

A major epidemic was averted due to high rates of vaccination in the surrounding communities.

Large outbreaks of the disease occur with regularity and major epidemics occur in cycles - usually every 8 to 12 years.

There were at least three, separate, major epidemics that decimated the population: smallpox (1520 to 1521), measles (1545 to 1548) and typhus (1576 to 1581).