Feral Cat Diseases

A feral cat is a feline that lives outdoors and has no owners. Some feral cats are tame, while others are wild, as they have never had human contact. Because they live outdoors and likely receive no health care, feral cats are at risk for developing serious diseases. Many of these diseases are contagious and are spread by coming in contact with other cats.



If you have an outdoor cat, it can potentially become sick from a feral cat. And if you bring a feral cat into your home where a cat already lives, the current feline can become ill if the feral cat is carrying a disease. Before you put your kitty at risk, you should know the diseases feral cats can carry.

  1. Rabies

    • The most dangerous disease a feral cat can carry is rabies. Rabies is a fatal virus that can be spread to humans as well as other mammals, such as foxes, raccoons and dogs. Rabies is spread through bite, which means that if the feral cat got into a tangle with a rabid animal and was bitten, it was likely infected with the deadly disease.

      If a rabid feral cat comes into your home or comes in contact with you or your animals, it could infect you. Always keep your animals’ rabies vaccinations current; and before you attempt to handle or trap a feral cat, you should receive a rabies pre-exposure vaccine, recommends the Feral Cat Coalition website. The length of time in which rabies vaccinations stay current in animals varies per state.

    Feline Immunodeficiency Virus

    • The feline immunodeficiency virus (FIV) is a condition that attacks a cat’s immune system, making it unable to fight off infections and cancers. It is similar to the human immunodeficiency virus, also called HIV. The feline version, however, can be spread only to other felines, states Dr. Holly Nash of the Doctors Foster and Smith website.

      FIV is spread to other cats through saliva, typically in the form of bite wounds. Although rare, it is possible for pregnant cats to spread the disease to their kittens if they become infected while pregnant or nursing. If an infected feral cat bites your cat, it could pass the virus on. Vaccines are available that can prevent the transmission of FIV; however, they are not 100 percent reliable.

    Feline Leukemia

    • Another disease that feral cats can carry is feline leukemia. According to Nash, this condition is a cancerous disease caused by the feline leukemia virus. Feline leukemia is similar to FIV, as they are both retroviruses. Feline leukemia is also spread through the saliva, like FIV; however, cats need only to come in contact with the saliva to become infected. For example, nose-to-nose contact between cats is enough to transmit the disease.

      It is extremely important to have the feral cat tested for feline leukemia before it comes close to your own cat. A vaccine is available to prevent cats from catching the virus, but it does not provide 100 percent protection.