Bed bugs are tiny blood-sucking insects that do not transmit disease but leave their victims itchy.

Bed bugs were a thing of the past in most Western countries by the early 1990s, but they have staged a spectacular comeback since the banning of the powerful insecticide DDT.

“The movement of travellers around the time of the Sydney Games helped to spread things around,” said Cameron Webb, an entomologist at Sydney’s Westmead Hospital. “Our message to visitors to London is make sure you’re not bringing them home.” 

Bed bugs take up residence wherever people sleep.

“From backpacker hostels to five-star hotels, from trains to boat cruises, anywhere people sleep, there’s now a risk factor there of bed bugs being present,” Webb said.

A hard, clamshell suitcase is a better luggage option than a rucksack with lots of hidey-holes, and for those worried about being an unwitting bed bug vector, stowing your luggage in the bathtub or shower is better than leaving clothes on the floor or unpacking and filling up hotel room drawers.

Do not put your faith in mosquito coils, roll-ons or aerosols, experts said.

“There’s no strong evidence that insect repellents provide much protection,” Webb said.

Once home, guard against a bedroom infestation by killing bed bugs that might have hitched a ride by putting soft belongings in a hot clothes drier for a 30-minute spin.

Webb said bed bugs cause some people great anxiety, especially the fear of unwittingly bringing them home and setting up a bedroom infestation.

“The message we always like to share is that your worry about bed bugs isn’t going to worry the bed bugs themselves,” he said.

“You’re better off being calm. Being aware of them is dramatically going to reduce the risk of both being bitten by them and bringing them home.”