The Balmis Expedition is a three year mission to the Americas led by Dr. Francisco Javier de Balmis with the aim of giving thousands the smallpox vaccine.

He sets off from La Coruña on 30 November 1803.

It may be considered the first international health-care expedition in history.

King Charles IV of Spain supports his royal doctor Balmis, since his daughter María Luísa had suffered the illness.

The expedition occurs on the Maria Pita ship and carries 22 orphan boys (8 to 10 years old) as successive carriers in vivo of the vaccine, Balmis, a deputy surgeon, two assistants, two first-aid practitioners, three nurses, and Isabel López de Gandalia, the rectoress of Casa de Expósitos a La Coruña orphanage.