The program decided to implement sentinel hospital-based type of surveillance using tertiary level hospitals of the Department of Health as sentinel sites with at least one hospital per region.

An in-depth data are gathered in a “community” of sentinel sites and the resulting analysis is used to inform programs and policies affecting a larger geographic area which, in the case of the ARSP, one region of the country.

The program started with only 8 laboratories all in Metro Manila and was later added with sentinel sites outside Metro Manila starting 1993.