The United States Public Health Service is the health component of the U.S. Department of Health and Human Services. It originated in 1798 with the organization of the Marine Hospital Service, out of concern for the health of the nation's seafarers who brought diseases back to this country. As immigrants came to America, they brought with them cholera, smallpox, and yellow fever; the Public Health Service was charged with protecting the nation from infectious diseases.

Today the Service helps city and state health departments with health problems. Its responsibilities include controlling infectious diseases, immunizing children, controlling sexually transmitted diseases, preventing the spread of tuberculosis, and operating a quarantine program.

The Centers for Disease Control in Atlanta, Georgia, is the Public Health Service agency responsible for promoting health and preventing disease.