U.S. Army doctor Col. William Gorgas paved the way for the construction of the Panama Canal by destroying the mosquitoes that spread disease and doomed an earlier French effort.
When the Panama Canal Commission began construction in 1904, they began with the remains of a failed French canal. The French effort ended in bankruptcy in part because too many workers were hospitalized or died due to infections of malaria and yellow fever. Some estimates put it as high as one-third of all workers.
In Colón, an important city near the future Atlantic entrance to the Panama Canal, about 1 out of every 6 people was infected with malaria at any given time.
When the U.S. bought out the French company and began work, Gorgas was named the chief medical officer of the project. He immediately set his sights on controlling malaria. Gorgas had previously controlled yellow fever and malaria in Havana, Cuba by applying the research of U.S. Army Maj. Walter Reed and British Army Dr. Ronald Ross.
Ross and Reed had previously proven, during experiments with other doctors, that mosquitoes were the primary way that many diseases spread.
Gorgas drew up a $1 million plan with engineers and other doctors to reduce or eliminate the mosquitoes along the route of construction. Unfortunately, many other decision makers, including President Theodore Roosevelt, supported the "bad air" theory that said the diseases came from the soil and vapors in the air.
Roosevelt was eventually persuaded by his personal physician to back Gorgas' plan.
Once he had the funding and support of the president, Gorgas launched one of the largest sanitation campaigns ever. More than 4,000 people were enlisted into mosquito brigades that deployed across the isthmus.
Workers cut all grass to less than 12 inches high, drained open water where possible or sprayed a film of oil on it where it wasn't. Custom poisons were spread across areas where larvae grew. Workers cleaned homes regularly and placed screens over windows and doors.
Progress was slow, but success did come. The campaign launched in the summer of 1905. In Aug. 1906, new yellow fever cases were at less than half of their historical norm. After Nov. 1906, no more canal workers would die of yellow fever. Malaria never went away completely, but in Jan. 1910 the death rate fell to 1 percent of the historical norm.
Gorgas went on to fight disease in South African gold mines before becoming the Army's 22nd Surgeon General.