The year-long study of more than 400 mice collected from seven sites in Manhattan, Queens, Brooklyn and the Bronx found they carry bacteria responsible for mild to life-threatening gastroenteritis in humans, and some of these bacteria may be resistant to antibiotics, CBS New York reports.
A second study in mBio found 36 viruses, including six new viruses, existing in mouse droppings.
IMPORTANCE Mice carry a wide range of infectious agents with zoonotic potential. None of the viruses, however, are known to infect humans. Some of the viruses that were found in mice were not associated with house mice. The researchers, conducting the largest survey of microorganisms living in city mice, also identified several genes that give germs resistance to antibiotic drugs. Most of the mice lived in trash compactor rooms in apartment building basements.
Although the study didn't establish a link between the pathogens found in NY mice and actual cases of bacterial infection in humans, Lipkin still advises caution.
A previous study of rats in NY by investigators at CII found several of the same pathogens, including E. coli, Salmonella, and C. difficile.More news: Body found at California SUV crash site identified as missing child
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"You not only have mice carrying bacteria that have the potential to cause human disease, but also carrying bacteria that have components that actually would thwart our ability to treat these infections with antibiotics", Lipkin said in a statement for NPR.
"If you've got mouse droppings and they're anywhere near food, for example, these need to be cleaned up with sterilizing disinfectant".
At least 2 million people are impacted by these superbugs every year and 23,000 of those are killed as a result, the Centers for Disease Control and Prevention (CDC) says. "One would really have to do the same experiments in the city and in the countryside to have a direct comparison", said Baines, who, for his own most recent research, "laid traps in and around farms" to find sick mice in the wild. These viruses, however, were linked to ones that infect other animals, including dogs and pigs, which indicates that the viruses can spread from species to species. "That's the normal state of animals, and it's true of humans as well, and the vast majority of these bacteria and viruses are harmless".
"I wouldn't think of mice in your house as Stuart Little", says Lipkin, who served as chief scientific consultant on the movie Contagion. Some of the bacteria had genes that confer resistance to quinolone and macrolide antibiotics and certain beta-lactams.
Together, the findings show that mice may be an untapped reservoir of potentially risky infections, and suggest that mouse populations should be studied when outbreaks of such infections occur - just as mosquitoes are investigated when cases of West Nile or Zika start to surge. "Those antibiotic-resistant bacteria are now capable of spreading to any number of unintended targets", said Schaffner.
"This is a hard kind of study to do, logistically", Lipkin said. "Then we only had to screen a tiny fraction of the entirety of the sequences that the computer was able to browse through", de la Fuente-Nunez says.