Homeowners in Cheshire are being urged to guard against a fresh invasion of rats this autumn.
Pest experts fear numbers could soar in the next few months boosted by a combination of cooler temperatures and increasingly wet weather.
A national survey carried out by the British Pest Control Association (BPCA) showed part of the county was among the areas which attracted the most call outs for rats per head in the UK last year.
And the trade body is warning sightings could rise once more as the onset of colder conditions prompts the rodents to abandon their summer habitats and seek food and shelter indoors.
BPCA technical manager Dee Ward-Thompson says residents should be doing all they can now to protect their properties.
She said: “Rain washes rats out of sewers and other nesting places and, inevitably, they go looking for shelter in higher ground.
“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.”
A typical home may have more than a dozen potential entry points for the rodents.
They get 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.”
BPCA says it’s much easier to prevent an infestation than to get rid of one and offers some simple precautions which can be taken to reduce the risk.
Inspect properties thoroughly and seal up any external gaps, holes or crevices that could provide rats with a way in.
Remove potential nesting sites by keeping yards and gardens clean and tidy, cutting back overgrown areas and clearing any piles of wood or debris.
Ensure doors and windows can be closed properly and that drain inspection covers are well maintained.
Keep bins well maintained with their lids closed, dispose of rubbish carefully and don’t leave leftover food lying around. Compost heaps should be covered.
Areas around bird feeders should be kept clean and pet food bowls should not be left out overnight.
It’s important for anyone who does find an infestation to employ recognised professionals, according to the non-profit BPCA – the leading national trade body for pest control.
Mrs Ward-Thompson said: “Rats must be dealt with by an expert technician who knows the area in question and their likely habitat, and knows how to treat any particular strain.
“Most people simply want the job done right first time and, by employing a company or individual affiliated with the BPCA, they can be sure they’re using an expert in the field.
“We’ve established strict criteria to ensure the professionalism of our members so controllers carrying our logo will carry out safe, effective and legal treatments.”