74% of UK Rats carry immunity to popular rodenticides

A new study of rats in the UK has uncovered that 74% carry a resistance gene, making them potentially immune to current pest control methods. This together with a 25% increase in the rat population due to lockdown means without a cold winter, 2021 may well be the Year of the Rat!

“It’s very worrying because this ‘hybrid-resistance’ means that some common rodenticides simply won’t work to control rat numbers, this together with a bumper breeding year means we are in for a heck of a ride in 2021 if we don’t have a very, very cold winter”

The 2019-20 Campaign for Responsible Rodenticide Use survey of rats showed that 74% of rats in the UK carried a resistance gene to popular rodenticides, and even more worrying in some locations in the UK, 20% have two different genes, making them super resistant.

• Learn about our Rat Control services here

“Although one such rat was found in 2017, this is the first time in the UK that ‘hybrid-resistance’ has been found on this scale, with potentially unknown difficulties for pest rodent control,” says Dr Buckle of the Campaign for Responsible Rodenticide Use. “This is happening because different resistance foci, that were once separate, are now merging and interbreeding.

Conditions this year have created a “perfect storm” for breeding rats with lockdown causing a 25% increase in the population of rats in the UK, with many people reporting seeing rats out in the open for the first time.

“This year has been very challenging for pest controllers with an increase of 25% in the population thanks to lockdown plus a shift in where rats are looking for food and shelter – the news that interbreeding is causing a resistance to the bait and poison we use to control infestations is very worrying for next year”, explains Rathbone.

The population of rats in the UK is now at around 150 million, up 25% from 2019.

This news is worrying for some homeowners in the UK where rat numbers have grown.

“The best deterrent I can recommend is removing all sources of food – bird feed is the worst at this time of year as bird lovers over stock bird tables, this high energy food is like a Michelin starred meal to rodents”, says Rathbone.

Pest.co.uk is issuing the following advice to anyone worried about rats in their home:

• Block up holes – Fill any gaps in brickwork, shed doors and any holes on external walls of your home including cellars and attics
• Clear cupboards – Empty unused cupboards of bags, clothes, rags and keep them clean
• Secure all food sources – Make sure food is not left out, tidy away any open food sources and keep worktops and floors clean of crumbs
• Prepare traps – by leaving out rat traps you can pre-empt any future infestation, however it is better to bait with official rat poison than leaving food scraps out – if in doubt get expert advice on the type of bait to use

“Without a very cold winter, we will be entering 2021 with huge numbers of breeding rats carrying a new resistance due to interbreeding to common pest control methods, it’s going to be interesting, that’s for sure!”, concludes Jenny Rathbone from Pest Control Experts Pest.co.uk