There were thousands of deaths, from typhus, in the German concentration camps because the Nazis refused to use DDT to kill the lice that spread typhus. Bad Nazis!
Dachau was “liberated” by American troops on April 29, 1945 after the camp had been turned over to them under a white flag of truce. The man who had surrendered the camp was immediately killed, but that’s another story.
On 2 May 1945, the 116th Evacuation Hospital arrived at Dachau and set up operations. According to a report made on 20 May 1945, there were 140 prisoners dying each day in the camp; the principle causes of death were starvation, tuberculosis, typhus and dysentery. There were 4,000 prisoners in the prison hospital and an unknown number of sick prisoners in the barracks who had been receiving no medical attention.
There were 18 one-story wooden SS barrack buildings in the Dachau army garrison which were converted into hospital wards. The medical personnel were housed in the SS administration building. A Typhus Commission arrived and began vaccinating all medical personnel and the prisoners. There was a daily dusting of DDT to kill the lice which spreads typhus.
On 3 May 1945, the sick prisoners were brought to the hospital wards. They were bathed, dusted with DDT powder and given clean pajamas to wear; their old prison clothes were burned.
By July 1945, the typhus epidemic in the Dachau concentration camp had been brought under control by the US Army doctors, and all the prisoners had either been released or moved to a Displaced Persons camp at Landsberg. The photograph immediately above shows former inmates being tested for typhus before being allowed to leave.
This quote from Wikipedia explains why DDT is harmful and is no longer used.
In 1962, the book Silent Spring by American biologist Rachel Carson was published. It cataloged the environmental impacts of indiscriminate DDT spraying in the United States and questioned the logic of releasing large amounts of potentially dangerous chemicals into the environment without a sufficient understanding of their effects on ecology or human health. The book claimed that DDT and other pesticides had been shown to cause cancer and that their agricultural use was a threat to wildlife, particularly birds. Its publication was a seminal event for the environmental movement and resulted in a large public outcry that eventually led, in 1972, to a ban on the agricultural use of DDT in the United States. A worldwide ban on its agricultural use was later formalized under the Stockholm Convention, but its limited use in disease vector control continues to this day and remains controversial, because of its effectiveness in reducing deaths due to malaria, which is countered by environmental and health concerns.
Along with the passage of the Endangered Species Act, the US ban on DDT is cited by scientists as a major factor in the comeback of the bald eagle (the national bird of the United States) and the peregrine falcon from near-extirpation in the contiguous United States.