UK holidaymakers are being urged to use insect repellent to protect themselves against bites and the diseases they can spread as travel to tropical countries rises among Britons.

Scientists from repellent testing facility arctec at the London School of Hygiene & Tropical Medicine recently launched the Bug Off campaign to highlight the issue.

According to analysis by experts from the School of Overseas Travel, the number of visits by Britons to tropical countries went up by two million between 2002 and 2012 (4.02m to 6.03m).insect bite

The scientific team who studied the effects of preventatives recommend applying repellents containing 20-50% DEET, a repellent applied to the skin to repel biting insects, when in countries with diseases spread by insects, such as malaria and dengue fever.

Although medicine and vaccines can prevent some diseases, they don’t prevent them all; in those cases, stopping the bite in the first place is seen as the best line of defence.

In their analysis of animal research and other safety assessments carried out previously, the researchers concluded that there is no evidence of association between severe adverse events and recommended DEET use.

They looked at case reports of people suffering encephalopathy (a brain condition) following exposure to DEET in the 1980s. The researchers stated that, even when allowing for underreporting, “the incidence of 14 reported cases of DEET-associated encephalopathy since 1957 is small when considered against the context of an estimated 200 million applications of DEET worldwide each year”.

Dr James Logan, Senior Lecturer in Medical Entomology at the London School of Hygiene & Tropical Medicine and Director of arctec, said: “Biting arthropods can transmit a whole range of diseases to humans and it is vital to protect ourselves.

“Vaccines and treatments are available for some diseases but not all and so the best way to keep as safe as possible is to use an insect repellent containing DEET and reapply it regularly.

“We want people to enjoy their holidays and tropical trips – we don’t want them ruined by illness so we want to do all we can to help inform and educate people about the facts rather than the many myths surrounding this issue.”

Dr Ron Behrens, Consultant in Travel Medicine and Senior Lecturer at the London School of Hygiene & Tropical Medicine, said: “Travellers often underestimate the need for and application of repellents. I always encourage them to take along enough supplies of repellent and always carry a bottle with them when out and about to maintain protection throughout the day and evening.

“If bites do happen, make sure they don’t become infected by applying an antiseptic and try to avoid scratching them.”