On Mar. 2, 1799, an amending act extended benefits of the Marine Hospital Service to officers and men of the U.S. Navy. This arrangement continued until 1818 after which the Navy built its own hospitals.

John Adams, second President of the United States, signed into law on July 16, 1798 the Act for the Relief of Sick and Disabled Seamen, which established what is now the Public Health Service. Twenty cents was deducted from the monthly wage of each merchant seaman to build or rent hospitals and pay for the medical care provided.

Castle Island in Boston Harbor was chosen as the temporary site for the first marine hospital.