Damp weather and low temperatures may have spoiled a few summer holidays this year – but they could also lead to a major health hazard in the shape of an invasion of rats.

Homeowners across North Somerset are being warned to take steps to protect their properties to prevent the scavengers getting inside as they search for food.

Experts from the British Pest Control Association (BPCA) say the combination of cool temperatures and heavy rain are likely to force the rodents to abandon their summer habitats and seek food and shelter indoors.

The bad news for people in North Somerset is that very few homes are likely to be safe – the BPCA says the average house has as many as 12 different places where a rat could find a way in, as they can squeeze through gaps of little more than half an inch wide.

The BPCA’s technical manager Dee Ward-Thompson is urging people to take steps to rat-proof their homes before they find themselves hosting some unwelcome visitors.

She said: “Rain washes rats out of sewers and other nesting places and, inevitably, they go looking for shelter.

“They’ll try to find some sort of dwelling and that could be lofts, garages or sheds.

“Our members report the number of calls to deal with infestations often rises in the autumn when the temperature drops often quite dramatically and we’re expecting a similar pattern this time.

“So it’s important for homeowners to do as much as they can to ensure they’re not among those affected.”

Rats can enter through gaps as small as 15mm, often using plumbing pipes and unscreened vents or gaps in the eaves and roof edges.

Mrs Ward-Thompson added: “The first evidence of rats in a home is often noises under the floor, in the walls or loft as that’s where most will head to once they’re inside.

“Quite apart from the health risks, they’ll foul water tanks and chew on wood or electrical wires which can cause a lot of damage and poses a fire hazard.

“They’ll also do their best to find sources of food, which means they can soon move to other areas of the house occupied by humans.

“Rats also breed rapidly and will create nests in attics or walls, so it’s vital to act as soon as any evidence is found.”