Carlos Juan Finlay (1833-1915) & Juan Gulteras (1852-1925)

Carlos Juan Finlay (1833-1915)

Juan Gulteras (1852-1925)

Two Cuban-born physicians, Carlos Juan Finlay and Juan Guiteras, endured years of ridicule and skepticism from the medical establishment while they advanced their novel theories to explain the spread of yellow fever. Eventually, their theories were accept¬ ed, and doctors were able to control the deadly disease.

Both men were raised in Cuba and later stud¬ ied medicine in the United States. As practicing physicians, Finlay and Guiteras also became experts in the study of tropical diseases, such as yellow fever and malaria, for which there were no known cures at the time.

Guiteras and Finlay worked together on the Havana yellow fever commission in 1879. Guiteras supported Finlay’s theory that yellow fever was spread by the bite of the common Havana mosquito, known in scientific terms as the Aedes aegypti. Neither doctor could prove the theory, however, and the skeptical medical community gave Finlay the unflattering nick¬ name of “mosquito man.”

Guiteras had also proposed a novel theory. Fie observed that people in areas where yellow fever was common developed lifetime immuni¬ ty to the disease after experiencing several mild bouts of it during childhood. The theory was significant because, if proven to be true, it would mean that doctors could develop a vac¬ cine for the disease.

It was not until 1898 that yellow fever became a high priority for the American med¬ ical community. That year, the Spanish- American War erupted, and the United States dispatched troops to Cuba. Prompted by the deaths of U.S. soldiers, the U.S. government established another yellow fever commission. It was directed by Walter Reed, a highly regarded surgeon in the U.S. Army.

Finlay convinced Reed and the commission to explore his theory about the role of the com¬ mon Havana mosquito in the transmission of the disease. Finlay and Guiteras worked with the commission and conducted experi¬ ments on human volunteers who agreed to be bitten by infected mosquitoes.

The Reed commission eventually confirmed the mosqui¬ to as the transmitter of yellow fever. After the U.S. government eliminated swamplands in Havana that served as breeding grounds for the insect, the incidence of the disease was dramatically reduced.Unfortunately, a number of human volun¬ teers who had worked with the commission died while under the supervision of Guiteras.

The outcry over their deaths brought an end to human experimentation. Guiteras was unable to prove his theory and replicate the lifetime immunity that he had observed in adults who had been exposed to yellow fever as children. It was not until twelve years after Guiteras’s death, in 1937, that doctors were able to isolate the yellow fever virus and develop a vaccine.