Spread of super mutant (ninja?) rats makes catchers ask for stronger poison West Berkshire council say they need more effective poison as the "super rats" have developed a resistance to common vermin control methods. Graham Chappell, from Rapid Pest Control in Newbury is contracted by West Berkshire Council. He said: It's becoming more of an issue now simply because of the number of rats that are being seen. They've also mutated genetically and are bred to be immune to standard poisons. It sounds like an opening to a comic book series, but the rats do carry diseases that can be passed on to humans so there is a concern to control their spread. A man also recently caught a giant rat in Consett earlier this year, with a video of his extreme catch (worth watching as long as you aren't scared of rats). Not a good year for musophobics.