Owning a pet comes with vet bills, ugly messes, and a sizable time commitment, but one liability most people don’t consider is the danger of contracting a disease from their pet. Recent news, however, has linked a cat-carried parasite called Toxoplasma gondii (T. gondii) to mental illness and schizophrenia.
Outdoor and feral cats have an increased likelihood of carrying the parasite, and the Centers for Disease Control and Prevention estimates that more than 60 million people in the U.S. may have T. gondii. However, most people never show symptoms even though the chances of developing mental illness due to the parasite are increased (though it's not clear by how much). Keeping cats indoors and cleaning the litter box daily can prevent contact with T. gondii. But there are more diseases out there than just T. gondii that you can contract from pets.
Exotic pets can be carriers, but most diseases come from our furry friends. "Reptiles are a concern for certain bacteria like salmonella, but by far the most common pets that cause illness are dogs and cats," says Dr. Polina Vishkautsan, an expert on small animal clinical infectious diseases at the UC Davis Veterinary Medical Teaching Hospital. "The main concern is when those animals are allowed to live in poor hygiene and not treated appropriately to prevent fleas and ticks."
The most common illnesses people get from pets are ringworms, toxoplasmosis, and cat scratch disease. Ringworms can be acquired from dogs and cats, and cause a fungal infection of skin from contact with animal feces. These worms, when swallowed by children, can cause blindness, but this is very uncommon. Toxoplasmosis can cause abortion or birth defects in pregnant women. But most women who get sick by contracting this parasite get it from undercooked food and not pet waste. Cat scratch disease is caused by a bacteria called bartonella, and it's carried by many healthy cats. It's rare that a scratch or a bite leads to the disease, but if a wound is inflated and is deep, seek medical attention.
Rabies, which is even less common but more dangerous, is mainly a disease of animals. Humans get rabies when infected animals bite them. And while these cases are very rare in the US, they can be fatal, so get any new dogs vaccinated. A person who is exposed and has never been vaccinated against rabies will need four doses of rabies vaccine after exposure.
Catching a disease from your pet is very preventable, says Vishkautsan, especially since most pets contract the illnesses they pass on to their owners from pests such as fleas and ticks. "Adequate external parasite control is very easy to do," she says. "And consult with your physician and your veterinarian if individuals in the household are immune-compromised, such as geriatrics, infants, and cancer patients." Maintenance of normal hygiene will ward off most risks: hand-washing before and after handling pets, daily cleaning of litter boxes for cats, and frequent picking up of feces in the yard for dogs. Also prevent excessive contact between pets and wild animal populations like rodents, deer, and feral cats.
Despite the risks, the benefits of having a pet outweigh the potential risks. Dog owners are less likely to be obese and get more exercise than the national average, according to the National Institute of Health. Studies by the Centers for Disease Control and Prevention and the National Institute of Health show that pet owners exhibit decreased blood pressure, cholesterol, and triglyceride levels, and that ownership lowers the risk for having a heart attack or heart disease later in life. More recent research also shows that pets improve the health of your microbiome and digestion. "We need to maintain the balance of providing disease prevention education while preventing irrational panic," says Vishkautsan. "Pets contribute to child development, provide mental therapy and companionship, and improve your overall health."