Mosquitos and The Panama Canal

The French and mosquitoes do not get along. Were it not for mosquitoes we might all be calling McDonald’s “Big Mac,” “Le Gran Mac” as John Travolta so eloquently pointed out in “Pulp Fiction.”

Napoleon sold Louisiana to the United States and lost Haiti, but the French kept a lease on the Panama Peninsula from Columbia. That six-mile strip of land was the only possible place to build a canal that would create a passage between North and South America. A passage was desired by all trading nations, and particularly attractive after the 1859 gold rush in California.

First Attempt to Build a Canal

Ferdinand de Lesseps, a Frenchman, decided it was time to build a canal to help regain France’s once prominent authority in the new world and make himself rich in the process. Lesseps had the experience, having helped plan and build the Suez Canal, and figured it couldn’t be that hard to build one in the swamps of Panama. Work began in 1882. Seven years later and an estimated 20,000 casualties, due mainly to yellow fever, Lesseps company was bankrupt. France’s lease was valid through 1903 so they needed a buyer, and once again, as was the case with the Louisiana purchase, the United States was willing and able.

Teddy Roosevelt Sets Sites on a Canal

President McKinley probably would have eventually signed off on the building of the canal, but he was shot. The United States at the time was an isolationist country. So long as we were left alone we let almost anything happen in the world. This all changed with the inauguration of Theodore Roosevelt. He carried a fifty-five gallon container of whoop-ass and was anxious to open it on the world. The canal was right up his alley. The ability to trade faster was fine, but the ability to get war ships from the east coast to the west in a third of the time was imperative.

The Mosquito Obstacle

Before any work on the canal could be attempted the most deadly problem in Panama had to be overcome. Roosevelt could not condone heavy losses of life, except perhaps those connected with battle, so he sent Doctor Gorgas, an experienced scientist, to examine the problem. Gorgas had worked in Cuba with Walter Reed who discovered, about the time that Roosevelt was walking softly and carrying a big stick up San Juan Hill, that mosquitoes transmitted, and were vectors of Yellow Fever. The problem was identified; now all Gorgas had to do was stop the mosquitoes from biting.

Breeding Sites, Natural and Man Made

The French didn't know mosquitoes were their main problem. They apparently didn't know about mosquito breeding habits or didn't care and had consequently developed a veritable mosquito paradise. Sewage and drainage ditches were everywhere along the canal and these provided breeding sites for mosquitoes by the millions. They also had a problem with a particularly voracious ant, the Sauba, or Umbrella ant. These ants carry leaves covering their bodies, thus umbrella, to their mounds and these mounds can reach forty foot in diameter. The Umbrella ants are not deadly, but there are so many of them that they will completely demolish a food storage in one night. So the French built trenches around their food storage to discourage the ants and the trenches attracted more mosquitoes.

A Solution is Found

Gorgas had the problem of all these man made breeding sites as well as all the natural ones. There were very few insecticides in the early 1900’s, so Gorgas decided to attack the mosquitoes where they were breeding. He discovered that a film of oil placed over the water would kill the mosquito larvae not allowing metamorphosis to occur. No adults, no eggs: the first larvicide. Gorgas got control of the mosquitoes and the canal was completed in 1914.


Alan Kerbey
Special Chemical Applications
Houston, Texas