Introduction
Mosquitoes, sandflies, tsetse flies, and other biting insects cause much inconvenience because of local reactions to the bites themselves and from the infections they transmit. Mosquitoes spread malaria, yellow fever, dengue and Japanese B encephalitis. Sandflies spread leishmaniasis and tsetse flies spread sleeping sickness.

Mosquitoes bite at any time of day but most bites occur in the evening.

Precautions to Take
1. Wear loose long-sleeved clothing and long trousers to limit the skin available for bites. Mosquitoes that spread malaria tend to bite at night, especially around sunset.

2. Mosquitoes may bite through thin tight clothing, so use loose clothing or use an insecticide or repellent on the clothing itself. Socks can be sprayed with repellents. Insect repellents should also be used on exposed skin but remember DEET, which is in many repellants, damages plastic including contact lenses.

3. Spraying insecticides in the room, burning pyrethroid coils and heating insecticide impregnated tablets all help to control mosquitoes. Air-conditioning tends to make mosquitoes less active.

4. If sleeping in an unscreened room, or out of doors, a mosquito net (which should be impregnated with insecticide - usually pyrethrum) is a sensible precaution. Portable, lightweight nets are available.

5. Garlic, Vitamin B and ultrasound devices do not prevent bites.