Control of Human Lice (Anoplura: Pediculidae) Infestations: Past and Present

Abstract

Removing lice by hand or with a lice comb, and shaving the scalp and body, were some of the oldest methods of controlling human lice. Date flour was used in the 16th century B.C. for this purpose. Later, quicksilver, cresol, naphthalene, sulphur, mercury, and kerosene, alone or in combination with oil and vinegar, also were applied. Today, insecticides used for the treatment of head and body lice include organochlorines (DDT, lindane), organophosphates (malathion), carbamates (carbaryl), pyrethrins (pyrethrum), and pyrethroids (permethrin, phenothrin, and bioallethrin). Despite the introduction of these effective insecticides, the number of cases of lice infestation has increased worldwide since the mid-1960s, reaching hundreds of millions yearly. This is because most of the products in the market are either ineffective formulations, or they have lost their efficacy because of the development of resistant strains of lice. Cross-resistance of lice to different pyrethroids has been reported in Israel and several European countries. Mosaic treatment, rotation of the pediculicides, and combination of 2 insecticides within the same formulation, should be implemented to slow the development of resistance. Future efforts should be directed toward the development of pediculicides based on new chemicals. Biological control of lice in humans may be of scientific interest only. Education of the parents on the biology and control of head lice is important.