In 1917 the United States Congress passed the Jones Act giving a large measure of self-government to the people of Porto Rico, in addition to making them citizens of the United States. This Act, in outlining the machinery of the local government, created a Department of Health whose Commissioner, appointed by the Governor, was placed on a parity with the heads of the other Departments, and given a place in the Executive Council, or Governor's “Cabinet.” Since that time the Department of Health has made remarkable forward strides.
Before 1917, the Division of Sanitation and Charities had been a minor, although efficient, branch of the government. Its change to a major branch shows the increasing importance being placed upon the question of the public health in Porto Rico.
Public health work may be said to have begun in 1918, when the Department of Health determined to initiate a systematic campaign against uncinariasis, then as now the most important and pressing problem confronting it.