I grew up with cats, and they were all indoor/outdoor. I never really thought about it since that was just the way things were done. Yet, as much as he’d like to convince us otherwise, our current cat Finnegan is an indoor cat. There are a lot of reasons for this.

One reason for keeping Finnegan in the house is zoonotic disease prevention. I was recently giving a talk about "Pets and immunocompromised owners" at the American College of Veterinary Internal Medicine forum, and a recurring theme for reducing the risks associated with cats was keeping them inside. (Want to reduce the risk of the cat being exposed to Toxoplasma? Keep it inside. Want to reduce the risk of Salmonella exposure? Keep the cat inside…).

Another important reason is the animal’s own health:

  • Cat vs car rarely ends well for the cat, and untold thousands of cats meet their ends on roads every year.
  • Cat vs cat isn’t as bad but can lead to cat bite abscesses and transmission of a few different pathogens such as feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV).
  • When outside, cats can also be exposed to various insect borne pathogens that can be of concern. This kind of risk varies between regions, with areas such as those where there are ticks carrying Cytauxzoon felis (a parasite normally carried by bobcats) perhaps being the biggest concern.

Wildlife is another concern, in two ways. Just like with cars, cat vs larger critter such as a coyote rarely ends well for the cat. From an ecological standpoint though, greater problems occur from cats killing smaller wildlife. It’s been estimated that free-roaming domestic cats kill billions (yes, Billions) of birds and small mammals every year. I won’t go into all the details here, but there’s a good article on the Canadian Cooperative Wildlife Health Centre’s website healthywildlife.ca about the impact such avid feline predators can have on local ecology.

Some people would argue that cats are better off going outside. Looking back at the cats with which I grew up, a lot died early because they were allowed to go outside. It’s hard for me to justify the risk to the cat, wildlife and public health for some anthropomorphic “he’d really enjoy being outside” argument.


  • Heather H

    This is a good, concise, and entirely fair argument that should resound with any cat owner.

    Anyone who believes that a cat’s enjoyment of outdoor freedom trumps its exposure to possible disease or injury (the “quality over longevity!” folks) should still seriously consider the many effects their cat can have on others’ environments – and this is even taking as a given that they’re neutered and not contributing to feral overpopulation. Peeing in the neighbor’s garage! Killing local wildlife, pests and endangered specimens alike! Harming or killing others’ pets through abscesses, infections or disease! There is more than your cat’s happiness to think about, and it’s unlikely kitty is the angel you think it is.

    Conversely, for anyone who could care less about their cat’s potential damage to the outside world and only their kitty matters, I’d think they would be swayed by the argument that kitty could be harmed or killed, or bring pests and disease into the house to potentially infect other pets. In my life my family has had cats whose habit of losing fights brought in a fortune in vet bills, and ultimately died of FIP/FELV; we’ve had spontaneous flea outbreaks that turn into months-long nightmares.

    Sure, it curtails the cat’s freedom and encourages laziness and obesity. But owning a pet is still a responsibility, as is being a good neighbor and conscientious of your effect on your surroundings. If you live on a farm and see a cat as a working animal that keeps away pests, that’s one thing, for sure. But if you live in a busy suburban/urban area and your house is too small for a cat, then rather than letting it roam outside OR keeping it cooped up, it may be best to seriously consider whether it would be fair to keep one in the first place.

  • Carolyn Cooper

    For the record, my cats too are indoor only.