Here is a little insect that with all his faults, and they are many, possesses certain virtues. He has solved the problem of race suicide, for he multiplies with astounding rapidity. He adapts himself easily, not to say gracefully, to uncomfortable, even unsanitary surroundings, and if he were permitted to speak in his own defense, would doubtless challenge you to show on all the pages of history any great military success attained by an army not accompanied and “egged on” as it were by cooties. Personally, I believe you would have difficulty in producing such an example.
— The Tar Heel World War Record 1917-’18, by J. R. Graham
Louse infestations during WWI were common and concern about louse-borne disease was so great that after the armistice of 1918, returning troops were deloused at home ports and quarantined for 2 weeks.
At the beginning of WWII, louse control involved dusting with NCI powder (96% naphthalene, 2% creosote, and 2% iodoform) or smearing vermijelli, made of crude mineral oil, soft soap, and water, along clothing seams. The delousing powder of choice was MYL, with pyrethrins as the active ingredient. Until DDT came along.
In 1942, a team of USDA entomologists, led by one Walter E. Dove, were drafted into the project of preventing louse-borne typhus in troops. They worked methodically, testing every chemical they could find to see what would kill lice. Among thousands of other samples, they received a waxy, granular substance from the Geigy Corporation in Switzerland.
Swiss chemist Paul Mueller had labored intensively at Geigy for four years to synthesize dichlorodiphenyltrichloroethane (DDT); the basic Swiss patent was granted in 1940. This compound was originally made in 1873 by an Austrian student, but had never received any particular attention.
Field trials now showed it to be effective not only against the louse; but also against a wide variety of pests, including the common housefly, the Colorado beetle, and the mosquito. Geigy began manufacting two products based on DDT, Gesarol and Neocide, in 1942.
Gesarol did kill lice, and every other insect in the lab, but a crumbly wax doesn’t work well as a delousing treatment, so the USDA crew did the unglamorous but essential job of reformulating it. By 1943, they were producing large quantities of several formulations, including powders and sprays, and they were referring to Gesarol by its generic name, abbreviated to DDT.
The USDA scientists promoted DDT only for a few circumscribed uses, including delousing and malaria control. Indeed, project director Walter Dove specifically cautioned against spraying the stuff willy-nilly outdoors, arguing as early as 1944 that DDT was “definitely poisonous,” and that its environmental consequences might be bad.
It’s the only pesticide celebrated with a Nobel Prize: Paul Mueller won in 1948 for having discovered DDT’s insecticidal properties. But by then problems related to extensive use of DDT were already beginning to appear; DDT was discovered to have a high toxicity toward fish. Rachel Carson’s 1962 book “Silent Spring” raised alarm about DDT’s carcinogenic affects on humans. The insecticide was subsequently banned in the United States in 1973, although it is still in use in some other parts of the world.
This WWII-era Army poster from the collection of the National Museum of Health and Medicine at Walter Reed Army Medical Center instructs how to delouse an incoming recruit with DDT. “Both sleeves then three shots fore and three shots aft at both the neck and waistband.” “When numbers are to be treated a seat for the subject saves the back of the operator. Don’t forget the head and hat.”
“Delousing Procedures for the Control of Louse-borne Disease During Contingency Operations,” Published by the Armed Forces Pest Management Board Defense Pest Management Information Analysis Center Forest Glen Section/Walter Reed Army Medical Center, 2005, http://www.afpmb.org/pubs/tims/TG6/TG6.pdf
The Tar Heel World War Record 1917-’18, by J. R. Graham, World War Publishing Company, Charlotte, N. C., 1921