Published online by Cambridge University Press: 15 May 2009
Modern contact insecticides (like DDT) in powder form are ideal for combating widespread lousiness; but for various reasons they are not suitable for disinfecting small numbers of infested people under civilized conditions. It appears that the most convenient, efficient method in these circumstances is a small-scale fumigation of the infested garments, in either a metal bin or a plastic bag. Ethyl formate, one of the liquid fumigants suggested for this purpose by W. A. L. David in 1944, has been further tested and found efficient. In a plastic bag the size of a potato sack (about 30 × 40 in.), four blankets can be deloused by a dose of 100 ml. with an hour's exposure or a quarter of this dose with an exposure of 5 hr. or more. An overnight treatment with this dose would be safe and convenient, costing about Is. and the actual operations would take only a few minutes.