Protection Against Insect Bites

To minimize insect bites, travellers should wear light-colored, long-sleeved shirts, pants and socks. The most effective topical insect repellent is N, N-diethyl-m-toluamide (DEET). Sprayed on exposed skin, DEET repels mos- quitoes, ticks, chiggers, fleas, gnats and some flies. DEET is available in formulations of 5-40% and 100%. Higher concentrations do not improve efficacy, but usually protect longer; 30-35% DEET formulations are preferred by Medical Letter consultants. A long-acting DEET formulation originally developed for the US Armed Forces (US Army Extended Duration Topical Insect and Arthropod Repellent - EDTIAR) containing 25-33% DEET (Ultrathon) can provide protection for 6-12 hours