The introduction of smallpox vaccine in 1803 and the adoption of immunization as a government function in Puerto Rico.
Rigau-Pérez
J G
JG
D000486:Allergy and Immunology / Q000266:history*; D049711:History, Modern 1601-; D011634:Public Health / Q000266:history*; D011647:Puerto Rico; D012899:Smallpox / Q000266:history*