Carlos Juan Finlay was a Cuban physician and epidemiologist. He is best known for his discovery that yellow fever is transmitted from infected to healthy humans by a mosquito.
Background
Ethnicity:
Finlay's father was Scottish, and his mother was French.
Carlos Juan Finlay was born on December 3, 1833, in Puerto Príncipe, Cuba, the son of Edward Finlay Wilson and Isabel de Barres. His father was a physician who had fought alongside Simón Bolívar, and his family owned a coffee plantation in Alquízar.
Education
An aunt who had a school in Edinburgh taught Finlay at home until he was eleven; he then went to France for further, more formal schooling.
Finlay attended Jefferson Medical College in Philadelphia, where he studied under Robley Dunglison and John K. Mitchell and his son, Weir. He graduated in 1855, rejecting lucrative offers to practice in the Spanish colony of New York City.
Career
After a brief trip to Peru, Finlay settled in Havana, where he practiced general medicine and ophthalmology. In Philadelphia, John Mitchell taught that malaria and other epidemic fevers were caused by living organisms. In 1879 the U.S. Yellow Fever Commission in Havana concluded that yellow fever was transmissible and that its vector was probably airborne, would attack a person once only, and produced a specific, self-limiting disease. Finlay had written much about yellow fever as arising from telluric influences, miasmata, and meteorological conditions. He had theorized that filth was converted into some hypothetical vegetable-animal germ and had suggested that alkalinity of air caused yellow fever. Working closely with the Commission, he shortly suggested that the disease was transmitted by the household mosquito, Culex fasciatus, now called Aedes aegypti.
Finlay thought that the mosquito’s bill acted in transferring virus in the same way as a dirty needle acts in transferring hepatitis. He considered that the morbific cause of the disease was carried from the blood of an infected patient to a healthy person, but did not mention any change in the material thus transferred. From 1881 until 1898 he conducted 103 experiments wherein he induced mosquitoes to bite yellow fever patients and then bite healthy recent immigrants. The experiments lacked control, because none of Finlay’s subjects was kept within screens or away from patients who had yellow fever. From the protocols it is known that yellow fever probably was not transmitted; nor were the experiments accepted by physicians and students of the disease in Cuba or elsewhere. Finlay became the laughingstock of the orthodox physicians of Havana.
Finlay thought that a mosquito which drew only a little blood and was only slightly infected would produce mild disease which would confer immunity. Although a shrewd observer and a splendid and kindly physician, he was not trained as an investigator and that he experimented at all was remarkable. When the Yellow Fever Board - Reed, Lazear, Agramóme, and Carroll - came to Havana in 1900 Finlay provided them with mosquitoes, eggs, and instructions for raising mosquitoes. He was also one of a team of physicians who verified the diagnosis of epidemic and experimental yellow fever, an essential function, since there was no laboratory test.
In 1900 Walter Reed and the Board excluded filth as the route for infection, found that Sanarelli’s yellow fever bacillus was the familiar hog cholera organism, and showed that the virus was transmittable to the female mosquito from an affected patient only during the first two to three days of the course of the illness. The mosquito then must incubate the virus for about two weeks before her bite could infect a susceptible person.
Finlay was exactly right in naming the mosquito as the vector of the disease and in identifying the variety of mosquito. The precision of his hypothesis is admirable, but his ideas were neglected - as were the similar proposals made by Josiah Notl in Alabama in 1854. Perhaps in atonement for their rejection of his ideas, Cubans have made Finlay a national hero, an honor well deserved for the brilliant hypothesis that he staunchly stuck to against universal disbelief. Happily he lived to see it proved correct.
Finlay was all his life an avid sportsman, swimmer, and horseback rider.
Besides Spanish, he was fluent in English, French, and German.
Physical Characteristics:
While in France, Finlay developed severe chorea which left him with a speech impediment - a lisp - that he never lost. In 1851, having returned home to Cuba, he nearly died of typhoid fever.
Quotes from others about the person
His obituary in the Journal of the American Medical Association on August 28,1915, noted his humility: "He lacked the genius for self-exploitation and having established his doctrine modestly lived on with no thought of further recognition".
Interests
Sport & Clubs
swimming, horseback riding
Connections
In October 1865 Finlay married Adela Shine, a native of the Island of Trinidad. They had three sons, Charles, George and Frank.