Med J Malaya, 1950;5.

Abstract

The prospects in Malaya in the immediate future may be briefly summarized as follows : For residual sprays, DDT and gamma BHC, unless some outstanding new compound appears, will continue to be the most widely used. Both kill the principal malaria carrier. Anopheles maculatus and gamma BHC for a short period after application also kills the common nuisance mosquito, Culex fatigans. Though DDT does not kill C fatigans it prevents them from resting in rooms and reduces the number of biting. Both insecticides should eliminate bed bugs Cimex hemipterus during the course of spraying and reduce cockroach infestation. For the elimination of cockroaches and ants from houses gamma BHC is superior to DDT but the effect is short lived. The other residual insecticides, Chlordane, Toxaphene, Methoxychlor and the newer products Aldrin and Dieldrin are not likely to be used extensively in Malaya. They cannot yet be purchased locally and on present indications have no outstanding advantages to recommend them instead of DDT or BHC. Personal protection against scrub typhus infection is now satisfactory. Either DBP or benzyl benzoate rubbed into clothing should prevent the attachment of mites for several days, and DMP is also effective if applied daily to the skin or clothing. The mite population in an infective area can probably be reduced effectively by spraying BHC on the vegetation, but this method of control is not likely to be attempted in many areas. DMP is a good mosquito repellent and forms the main ingredient of several commercial preparations; it is not as effective when incorpora ted in a cream as it is when pure. Of the several simple, efficient remedies now available for head louse and scabies control, gamma BHC in coconut oil is probably the most useful because of its cheapness, ease of application, and effect on both parasites.