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Finlay, Carlos Juan

Finlay, Carlos Juan

(b. Puerto Prínciple[now Camagüey], Cuba, 3 December 1833; d. Havana, Cuba, 20 August 1915)

medicine.

Finlay was the son of a Scotch father and a French mother whose family lived in Trinidad. An aunt who had a school in Edinburgh taught him at home until he was eleven; he then went to France for further, more formal schooling. There he 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. Undaunted, Finlay became and remained all his life an avid sportsman, swimmer, and horseback rider. Besides Spanish, he became fluent in English, French, and German.

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. After a brief trip to Peru, he 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 organism. 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 (who volunteered for the experiment, knowing that they would eventually get yellow fever anyway, since everyone did). 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 we know 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, Agramonte, and Carroll—came to Havana in 1900 Finlay provided them with 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 Nott 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.

BIBLIOGRAPHY

I. Original Works. Finlay’s works have been collected as Obras completas, 4 vols. (Havana, 1965-1970).

II. Secondary Literature. The best biographical source is his son, Carlos E. Finlay, Carlos Finlay and Yellow Fever (New York, 1940). See also William B. Bean, “Carlos Finlay,” in Current Medical Digest, 37 (1970). 366-367; S. Bloom, Dr. Carlos J. Finlay (Havana, 1959); J.A. Del Regato, “Carlos Finlay and the Carrier of Death,” in Américas (May 1968); “Editorial. Carlos J. Finlay (1833-1915). Student of Yellow Fever,” in Journal of the American Medical Association, 198 (1966), 188-189. A further source of information on Finlay’s life and work is Cesar Rodriguez Exposito, Centenary of the Graduation of Dr. Carlos J. Finlay in Jefferson Medical College (Havana, 1956).

William B. Bean

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Carlos Juan Finlay

Carlos Juan Finlay

The Cuban physician and epidemiologist Carlos Juan Finlay (1833-1915) discovered that certain mosquitoes transmit yellow fever.

Carlos Juan Finlay was born in Camagüey Province on Dec. 3, 1833, of a Scottish father and a French mother. He spent his early years on his father's coffee plantation but soon was sent to school in France and England. From there he traveled to the United States, where he received a degree in medicine at Jefferson Medical College, Philadelphia, in 1855. He returned to Cuba and began to practice medicine after revalidating his degree at the University of Havana. From Cuba he traveled to Peru, Trinidad, and France, working in various hospitals. In 1870 he settled in Cuba permanently, developing an interest in the island's sanitary and health problems.

When, in 1879, an American mission arrived in Cuba to study the causes of yellow fever, the Spanish government designated Finlay to work with the group. He developed the idea that the transmission of yellow fever required a vector. At the International Sanitary Conference, held in Washington in February 1881, he explained his theory. In August Finlay read before the Academy of Sciences of Havana his historic work showing a mosquito, Culex fasciatus or Stegomyia fasciata (later known as Aedes aegypti), to be the vector of the yellow fever organism. Although Finlay advanced numerous experiments and observations to support his conclusions, his theory was not accepted by the scientific world for almost 2 decades. In a report to the International Sanitary Conference held in Havana in 1901, Walter Reed confirmed Finlay's discovery.

When United States troops landed in Cuba in 1898 during the Spanish-American War, Finlay worked with the American army in Santiago de Cuba. He further tested his theories in practice and advocated a campaign against the mosquito. As a result of his urgings, W. C. Gorgas, United States health chief in Cuba, began a program, later extended to Panama, to exterminate the mosquito, thus putting an end to a sickness that had plagued the Caribbean for many years.

In addition to his work in the epidemiology of yellow fever, Finlay wrote extensively on ophthalmology, tuberculosis, tetanus, trichinosis, filariasis, leprosy, beriberi, cholera, and exophthalmic goiter. After the establishment of the Cuban Republic in 1902, he was appointed public health chief, and the Cuban government created in his honor the Finlay Institute for Investigations in Tropical Medicine. Finlay died in Havana on Aug. 20, 1915.

Further Reading

Carlos E. Finlay, Carlos Finlay and Yellow Fever (1940), is a valuable work by Finlay's son and includes most of the Cuban scientist's writings on yellow fever, as well as a section on his life. A collection of essays on Finlay published by the Cuban Ministry of Public Health is Dr. Carlos J. Finlay and the "Hall of Fame" (1959). See also Enrique Saladrigás y Zayas, A Tribute to Finlay (1952). □

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Finlay, Carlos Juan

Carlos Juan Finlay (kär´lōs hwän fēnlī), or Charles John Finlay (fĬn´lē), 1833–1915, Cuban physician of Scottish and French descent; studied in France; M.D. Jefferson Medical College, Philadelphia, 1855. Settling in Havana, he began his life work on yellow fever, suggesting in 1881 the mosquito as carrier and in 1882 specifying the genus Stegomyia. The Reed Commission of 1900 inaugurated experiments that conclusively proved his theories. Finlay served as chief health officer of Cuba from 1902 to 1909.

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Carlos Juan Finlay

Carlos Juan Finlay

1833-1915

Cuban Physician, Epidemiologist and Public Health Reformer

Although the American physician Walter Reed (1851-1902) is generally associated with the discovery of the means of transmission of yellow fever, it was the Cuban physician Carlos Juan Finlay who first provided evidence that the Aedes egypti mosquito served as the vector of the disease. Yellow fever was one of the most feared epidemic diseases of the nineteenth century. An understanding of the means of transmission of the disease led to a fairly high level of control over the disease and was instrumental in the successful completion of the Panama Canal.

Finlay was born in Camagüey, Cuba. His father was a Scottish physician and his mother was French. Finlay attended schools in France and Germany before enrolling at Jefferson Medical College in Philadelphia. While a medical student, Finlay became interested in Professor John Kearsly Mitchell's suggestion that an unseen botanical agent was the cause of tropical fevers. After obtaining his M.D. degree in 1855, Finlay continued his training in Paris. He returned to Cuba in 1863, where he established a private practice and pursued his interest in public health medicine.

Yellow fever was one of the most feared epidemic diseases of the nineteenth century. The disease was endemic in the Caribbean islands, but outbreaks also occurred in North America. Almost nothing was known about the cause of the disease or its means of transmission, and preventive measures seemed futile. In 1879 an official U.S. Yellow Fever Commission was sent to Cuba for an investigation. The Spanish government appointed Finlay to serve as the local liaison officer. After his participation in the work of the commission, Finlay developed new ideas about the disease and began his preliminary investigations.

At the International Sanitary Conference held in Washington, D.C., in 1881 Finlay pointed out the futility of the sanitary measures being used to fight the spread of yellow fever. He believed that an intermediate agent transmitted the disease from the sick to the healthy and that effective control measures would require the destruction of this vector. Finlay suspected that a mosquito served as the vector of yellow fever. After considering the characteristics of various species, he decided to investigate the Culex mosquito (Aedes aegypti), a nocturnal insect with a short flight span. Finlay collected eggs, hatched them, and allowed selected mosquitoes to bite patients with yellow fever. To confirm his hypothesis he needed non-immune volunteers who would allow themselves to be bitten by the infected insects.

Finlay obtained permission from the military authorities to inoculate soldiers who had recently arrived from Spain. Finlay eventually inoculated over one hundred volunteers, but the results were not always consistent. In 1894 Finlay presented his results and his recommendations for the control of yellow fever at the Eighth World Congress of Hygiene and Demography. He suggested that patients should be isolated, houses should be fumigated to keep away mosquitoes, and potential mosquito breeding sites should be eliminated.

In 1897 Giuseppe Sanarelli claimed to have discovered a bacterial agent that caused yellow fever. The Surgeon General of the U.S. Army appointed a Board to study the infectious diseases of Cuba. The Board included Major Walter Reed, James Carroll (1854-1907), Jesse Lazear (1866-1900), and Aristides Agramonte (1869-1931). The Board quickly discovered that Sanarelli's alleged causal agent was simply a bacillus frequently found in cadavers.

On August 1, 1900, the members of the Board visited Finlay, who gave them the eggs of the mosquito that seemed to be the vector of yellow fever. Lazear hatched the eggs and allowed the mosquitoes to bite yellow fever victims. Lazear then allowed the mosquitoes to bite several volunteers, including Carroll and himself. Carroll recovered from a severe case of yellow fever, but Lazear died. In October 1900, at a meeting of the American Public Health Association, Reed announced that a mosquito was the intermediate agent of yellow fever.

When he returned to Havana, Reed directed a program of controlled experiments that provided proof for Finlay's hypothesis. Leonard Wood (1860-1927), a physician who was serving as Military Governor of Cuba, called the confirmation of Finlay's doctrine the most important step forward in medicine since the discovery of the smallpox vaccination by Edward Jenner (1749-1823). Major William Gorgas (1854-1920) also praised Finlay and used the methods Finlay had suggested in the battle against yellow fever in Cuba and Panama.

LOIS N. MAGNER

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