Bites and stings Dr Trisha Macnair Insect bites and stings are rarely more than an irritation in the UK, but if you're abroad insects can pose a significant danger.

In this article

Possible problems in the UK Possible problems abroad

Can bites transmit HIV? How can they be prevented?

How are they treated?

Allergy to wasp stings can trigger potentially fatal anaphylactic shock, with symptoms including breathing problems and an extreme drop in blood pressure.

It's possible to protect yourself from such an allergy by having a series of injections of diluted venom.

If you are stung, you should remove the bee or wasp sting as quickly as possible, before the venom can be released.

Mites, ants, fleas and mosquitoes are also common causes of irritating insect bites.

When you travel further afield, you risk a much nastier dose of poison with far more unpleasant effects. Stinging caterpillars in the southern US, for example, can cause severe pain, dermatitis and even intestinal disturbances.

The bites of more than 600 species of scorpion can lead to problems, ranging from a simple nip to (very rarely) an injection of fatal paralysing toxins.

Many insects carry infectious organisms that are passed on when they bite. These infections include malaria from mosquito bites, especially in Africa, Asia and South America, relapsing fever and Chagas disease from bed bugs in Mexico, yellow fever from mosquitoes in Venezuela and Lyme disease and Rocky Mountain spotted fever from ticks in eastern US states.

Always check for potential problems in the country you're travelling to, and get yourself vaccinated if you can.

Studies have shown no evidence of HIV transmission through mosquito or other insect bites.

When a mosquito bites a person it doesn't inject its own or a previously bitten person's blood, but saliva. In addition, HIV lives inside an insect for only a short time, so even if a mosquito bites someone with HIV, it doesn't become infected.

Follow these general rules to avoid insect bites and stings:

• Learn about the risks in the area you're visiting
• Cover up when outside, wearing full-length trousers, socks and long sleeves
• Use insect repellents, following the directions on the label
• Try to stay indoors at dawn and dusk when mosquitoes are most active
• Use insect screens on doors and windows
• Mosquitoes often breed in stagnant water, so don't let it collect around your home, in ditches, gutters or pools
• Don't camp overnight near freshwater swamps
• Don't leave litter or food where it may attract wasps
• Get experts to deal with nests when you find them
• Treat pets regularly to prevent fleas

In many cases, all that's needed is to clean the bite or sting and reduce any irritation with local anaesthetic or anti-histamine cream.

However, you should seek urgent medical help if:

• You're not sure what caused the bite
• You have an allergic reaction
• The insect could be dangerous (a scorpion, for example)
• You're in a malarial area

This article was last medically reviewed by Dr Rob Hicks in November 2007