American Fancy Rat & Mouse Association

This article is from the WSSF 2014 AFRMA Rat & Mouse Tales news-magazine.

Medical - Rodent Diseases Contagious to People

By Karen Robbins

While a person can get a number of diseases from many species of animals, it is unlikely, though not impossible, to get something from pet rats or mice. There have been very few incidents of diseases that have been known to have come from domestic pet rats. Being informed of the various risks involved with any species you choose for a pet is important as well as practicing good hygiene before/after handling your pet of choice (parents need to be diligent in educating their children on hand washing before/after handling their pets). And don’t let pet rodents be exposed to wild rats or mice at any time. Also, buying your pets from reputable/responsible breeders is recommended rather than pet shops. For years we have heard of problems of people getting sick animals, pregnant animals, animals that carry diseases that can be fatal to the pets at home, animals that have lice or mites, or those that just don’t live very long, but now that “Rat Bite Fever” (Streptobacillus moniliformis) is being found in pet shops makes for yet another reason not to buy your pet rodents there. Since the big pet shops acquire their rodents from brokers or commercial breeders, you don’t know what kind of pet you are getting (health history, if there are any temperament issues in the line, how they were cared for/amount of handling they received prior to arriving at the pet shop). Each species of animal ends up all together from the various sources in the same cages which is very stressful for them, so you can be introducing disease to ones that are healthy which then results in everyone potentially getting sick/carrying disease.

It is a more common problem to have allergies to the rat urine or bedding used (see the article “Animal Allergies”), rather than getting a disease from them. Changing the bedding should take care of any bedding allergies.

Rat Bite Fever is a rare disease and even rarer that it is fatal. Contrary to the name, “Rat Bite Fever” is not just something rats can carry but many other species of rodents as well as other animals. Also, you don’t have to get bit to contract this disease from an infected animal, but a scratch from an infected animal or ingesting contaminated products (from infected rodent droppings) may be ways to get it. We have an article on “Rat Bite Fever” from our vet/pathologist. There are also many online research articles and books with information on this disease (one is Handbook for Zoonotic Diseases of Companion Animals)

We also have other articles on possible diseases (again rare) and problems:
“Illness in Rat Bites and Feces?”
“Leptospirosis in Pet Rats?”
“Papilloma Wart Virus or Rat Pox Virus”
“Contagious Rat Diseases?; Zoonotic Diseases”
For more on zoonotic diseases see “Zoonotic Diseases” from the UC Santa Barbara Office of Research web site (archived page)
“Ringworm & Rats”
“Ringworm on Mice”

There is an article by the HPA (Health Protection Agency; part of Public Health England) “Reducing the risk of human infection from pet rodents.” (PDF file; and in a PDF brochure) that goes into detail on caring for pet rodents that may be suspect to harboring disease such as leptospirosis, hantavirus, rat bite fever, or lymphocytic choriomeningitis (LCMV).

Having pet rodents is no more dangerous than having pets of other species and the reward and companionship they give to their owners is just as much (or more) as other common pets. Rats have been kept as pets since the 1800s (see “History of Fancy Rats”) which shows just how much of a great pet they are, where mice have been domesticated since 1100 B.C. (see “History of Fancy Mice”). Rats and mice are the most common animals used in research to study human diseases and find cures. A vet can do tests on a person’s pets to determine their health status.

And yes, rats make GREAT pets (talk to any rat owner or read the stories in “Our Pets & Friends” section on the web site). *

Additional reading: Guide to Diseases Spread by Animals by Wildlife Removal. New!

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Updated February 10, 2021