Yellow fever made its first appearance at the project during the summer of 1881 when the French company started digging.  The company's records list 60 deaths during the first year (almost certainly an underestimate), but de Lesseps denied that there was an epidemic in Panama.  In fact, more probably died then, as they certainly did over the entire period of construction, from malaria than from yellow fever.  There was no immunity to malaria, but because it was a constant presence in the region, it was known and expected.  

Yellow fever did leave its survivors with immunity, yet it occurred in epidemics that swept through areas with swift vengeance.  Many of the Panamanian natives had childhood immunity to yellow fever, so it was the French, Americans, and other outsiders who suffered most from "the white man's disease."  The symptoms of yellow fever were also worse than those of malaria.  With both diseases, victims had insatiable thirst, chills, and high fever.  Yellow-fever sufferers, however, endured severe aches in their heads, backs, and legs; became extremely restless; turned yellow, especially in the face and eyes; and vomited dark blood.  People often refused to touch victims for fear of contracting yellow fever, and quickly buried the dead.

When the French began their Panama Canal project, there was no cure for yellow fever, although quinine was taken as a malaria preventative.  The predominant theory among scientists and the public was that both diseases were caused by poisonous vapors, such as from swamps or marshes (malaria is Italian for "bad air").  Sewage, rotting animal carcasses, the patient's clothing, and other filth were considered as contagions for the airborne disease.  People tried to avoid the wind and night air when yellow fever was present.

In 1848, however, Dr. Josiah Nott of Alabama had published a paper in the New Orleans Medical and Surgical Journal in which he denied that vapor causation theory and hypothesized that insects, perhaps mosquitoes, transported yellow fever and malaria.  In the 1850s, Dr. Lewis Beauperthuy in Venzuela and Dr. Albert Freeman Africanus King in Washington, D.C., came to similar conclusions.  The medical community and the public, though, ignored their conjectures.  

In 1881, the year the Panama Canal project commenced, Dr. Carlos Juan Finley, a physician in Havana, Cuba, often the site of yellow fever epidemics, not only observed that mosquitoes spread yellow fever, but correctly identified the exact species (out of 800) that was the carrier.  It was a wonderful example of scientific imagination, but Dr. Finley could never produce evidence to support his theory.  Thus, he, too, was ignored.

Meanwhile, in the French hospital in Panama, bed legs set in pans of water to keep ants from climbing on the patients provided a breeding ground for mosquitoes.  There were also no screens on windows or doors, and open pots of water abounded in homes (for drinking) and in gardens (to keep pests off plants).

Finally, in 1897-1898, Dr. Ronald Ross, an English physician in India, proved that a certain type of mosquito absorbed a malaria-causing parasite into its salivary gland by biting a malaria victim.  The parasite multiplied within the mosquito, which then spread the disease by biting healthy people.  Dr. Ross was awarded the Nobel Prize for his momentous discovery.  

In 1901, a yellow fever epidemic erupted in Havana, which was under the control of American occupation forces following the Spanish-American War of 1898.  Dr. Walter Reed, who headed the American medical corps in Cuba, agreed that the mosquito was also to blame for spreading yellow fever.  Although initially skeptical, Dr. William Gorgas convinced Reed, his superior, to test the theory by eradicating the mosquito from Havana.  Amazingly, in eight months, Gorgas and his men were able to do just that, halting the yellow fever epidemic.  Playwright Sidney Howard dramatized their heroism in his play, Yellow Jack (which was later made into a movie).

When the United States took over the Panama Canal project in 1904, chief engineer John Walker of the Isthmian Canal Commission called the mosquito theory "balderdash," despite Ross's Nobel Prize work on malaria and Gorgas's success against yellow fever in Havana.  The rest of the commission agreed.  The health officer appointed to the project, though, was Dr. Gorgas, who planned to attack the problem of yellow fever first.  In Panama, however, he faced a large geographic area, limited supplies, and resistance from his commanding officers who thought chasing mosquitoes was a waste of time, money, and manpower.

Beginning in November 1904, cases of yellow fever began to appear, and in January 1905, headlines in American newspapers blazed "Yellow Jack in Panama!"  Panic was spreading in Panama as 200 of the staff resigned over a two-week span, and three-quarters of all Americans left before the situation was under control.  President Roosevelt, who had witnessed cases of yellow fever while fighting in the Spanish-American War, realized the Canal Commission members were a major obstacle, so forced their resignation.  Roosevelt named John Stevens as the new chief engineer.

With the president's blessing, Stevens cut red tape and allocated all the resources necessary to end the yellow fever epidemic.  Whereas Gorgas's budget had previously been $50,000, the physician now got $90,000 just for screen-wire.  Gorgas and his workers put screens on windows and doors, fumigated houses, isolated victims, oiled cisterns weekly, and replaced standing water with running water.  Not surprisingly, the task took longer than in Havana, but incidents of yellow fever dropped dramatically by the fall of 1905, and within a year-and-a-half, the Panama Canal Zone was rid of the dreaded disease.

Robert C. Kennedy