Posted on 06/24/2026 5:24:56 PM PDT by Red Badger
Scientists have uncovered a disturbing change in both mice and rats infesting America's biggest cities, making the rodents harder to kill than ever before.
Researchers at Rutgers University in New Jersey found the vast majority of smaller house mice and larger brown rats in New York, New Jersey, Pennsylvania and Washington DC have genetically mutated to become more resilient to poison.
Specifically, five out of every six rodents tested displayed at least one mutation in the Vkorc1 gene, which has been found to affect how well the poisons work.
This study of nearly 300 house mice and brown rats also confirmed that more than 69 percent of the rodents carried additional genetic mutations, which previous studies have proven make rodents immune to common exterminator poison.
The changes were significantly greater in the smaller house mouse, which typically measures between two and four inches in length and can squeeze through the tightest space to get inside homes.
Meanwhile, the brown rat, also known as the sewer rat or Norway rat, which can grow up to 10 inches long, was found to be much more susceptible to common pesticides as they displayed fewer of the mutations.
Rutgers postdoctoral researcher and lead study author Jin-Jia Yu said in a statement: 'Genetic mutation is not that special in these creatures. But we found that the house mouse shows a lot of genetic mutations related to rodenticide resistance.'
In large urban areas, rodent infestations have been a continuous public health threat for decades, as scientists consider them a major source of disease transmission from animals to humans, passing on illnesses such as hantavirus, salmonella and plague.
(Excerpt) Read more at dailymail.com ...
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Are they Rodents Of Unusual Size? 🤨
Thank goodness most US cities are run by Democrat mayors! They’ll know how to handle this crisis.
And by that I mean they’ll blame Trump. Then they’ll raise taxes on anyone unlucky enough to still be living there.
A good barn cat can work wonders.
I’ve seen rats bigger than cats!...........
There was an old The New Avengers episode about a giant mutant rat entitled GNAWS. (Because JAWS was the blockbuster a year earlier.)
Article only mentions resistance to the warfarin type. Zinc phosphide probably still works well.
Just be glad they aren’t Capybara Rats.
Biggest on the globe!
Adaptation is a hell of a thing...
And don’t forget the giant rat of Sumatra, a story for which the world is not yet prepared.
Rat Fink! I still have mine from a bubble gum machine.
Now, I have to look that one up!
I’m sure I’ll be wishing I hadn’t.
Capybaras are rodents, but not rats. (Different branch of Rodentia.)
They can make nice pets, if you have a little water feature for them to play in...
“Mutant sewer rats spreading through major US cities ...”
They are called democrats.
Hey, maybe they can make some of them into superheroes, like the Teenage Mutant Ninja Turtles.
It was from the Sherlock Holmes story “The Adventure of the Sussex Vampire”, in which Holmes makes a passing reference to the giant rat of Sumatra but doesn’t actually tell the story.
IIRC, the TMNT’s sensei is a mutant rat ...
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