Insect repellents must be worn when in hot countries in order to reduce the risk of contracting serious vector-borne diseases.
This is the advice of Dr James Logan of the London School of Hygiene and Tropical Medicine, who explained good quality insect repellent is an essential back-up when vaccines and treatments for malaria and other diseases are unavailable or ineffective.
Expats who have recently moved to a hot foreign country and taken out expatriate healthcare insurance may want to consider using repellent until they have become accustomed to the climate and Dr Logan advised regular application to ensure it is as effective as possible.
"Many repellents only work at a short range and should therefore be applied like a suntan lotion – with complete coverage on exposed skin," he remarked, adding sweating and rubbing can cause it to be removed quickly.
"Repellents can be applied to clothing as well as skin but work best on the skin," he added, noting wearing long-sleeved shirts and long trousers will minimise skin exposure and therefore reduce the risk of bites occurring.
The foreign office also advises sleeping in a properly screened and air conditioned area if possible and using a mosquito net to minimise the risk of being bitten at night.
Deet is the most common active ingredient in most repellents and Dr Logan stated it is "one of the most effective" ways of dealing with mosquitoes and other disease-spreading insects, advising individuals to use a liquid that contains at least 20 per cent deet.
However, the ingredient does have drawbacks, as it has the potential to melt plastic items such as sunglasses or watch straps, as well as decolourise fabrics.
"Deet has a very good safety record but you should always follow the label. Like all repellents, Deet is not necessarily 100 per cent effective all of the time," he concluded.