National Doctor’s Day is observed in Cuba every December 3, commemorating the birthday of Carlos Juan Finlay, a notable Cuban physician and epidemiologist born in 1833. The day celebrates Finlay's significant contributions to medicine, particularly his discovery of the mosquito as a transmission vector for yellow fever, which was confirmed by the U.S. Yellow Fever Commission in 1900. This professional holiday emphasizes the vital role of Cuban doctors in the country's healthcare system. Finlay's work in epidemiology and his tenure as chief health officer of Cuba from 1902 to 1909 highlight his impact on public health. The observance serves to honor the dedication and achievements of medical professionals in Cuba.