Comb over Chemicals: Tool may rid heads of pesticideproof lice

When used systematically for 2 weeks, special combs may be more effective than a single, one-day application of an insecticidal shampoo at ridding a child’s scalp of head lice.

In some countries, including the United States and England, many lice have become resistant to pesticide treatments such as permethrin and malathion in lice shampoos (SN: 9/25/99, p.