DEAR READERS: I am sure many readers who love cats and wildlife will appreciate the article "The Outdoor Cat: Neighborhood Mascot or Menace?" by New York Times reporter Maria Cramer. She makes it very clear that one of the best solutions is an outdoor cat enclosure, or a "catio," to help protect wildlife and cats from injuries and cat-to-cat diseases.
But I was surprised at one serious omission in her article: No mention was made of the number of diseases cats can pick up outdoors and bring back into the home if they are allowed to roam free. These are called zoonotic diseases, and cats are more of a public health risk in this way than rats! According to the Merck Veterinary Manual (2010), there are at least 27 known cat-to-human zoonotic diseases. In addition, cats have infected people with influenza virus and COVID-19, and vice-versa. In contrast, a report from Washington State University lists only 12 rodent-to-human zoonotic diseases (see iacuc.wsu.edu/zoonoses-associated-with-rodents-wild).
As for cats controlling rats, adult rats are a challenge for most cats. Even if they do catch or kill one, cats (and their families) could be at additional risk from diseases the cat could catch from the rodent.
People are potentially at risk, children in particular, from petting any stray cat or from living with an indoor-outdoor cat. It is especially worrisome for children to play in sandboxes and other playground and garden areas where cats may have evacuated.
There is no need to get rid of your outdoor-indoor cats! Just visit the excellent American Bird Conservancy guide (abcbirds.org/program/cats-indoors) on how to make indoor life a safe and stimulating place. Ideally, you should have two cats, plus an outdoor enclosure or catio.
CATS OUTDOORS AT RISK FROM FUNGAL DISEASES
Often underdiagnosed when cats go blind, develop a fever, become lethargic or anorexic, or develop skin nodules and respiratory distress, histoplasmosis is a fungal disease in the soil. It is the second most commonly reported fungal infection in cats, following cryptococcosis.
Cryptococcosis is a type of fungal infection that occurs when a cat inhales spores from a type of fungus that grows in organic material such as soil, decaying wood or bird guano (especially droppings from pigeons). Spores also can enter the skin through an open wound.
Since these fungi are everywhere in the soil, cats are likely to get the soil on their paws and ingest it when grooming, along with fungal spores. The spores could be inhaled or get into the fur in dry and dusty weather and when cats dig into the soil chasing small rodents or making a pit in which to defecate. These fungal diseases are a major reason to keep cats indoors and never use soil in the cat's litter box.
The results of an experiment in Japan, published in Current Biology, reported that some dogs got watery eyes when reunited with their owners after more than five hours apart. The "tears of joy" response appeared to be driven by production of oxytocin, or the "feel-good hormone." People looking at photographs of dogs were more likely to want to nurture ones with watery eyes, suggesting that dogs might have evolved to tear up to get affection. (Full story: The New York Times and The Guardian, both Aug. 22)
Readers have informed me that their dogs shed tears when distressed. Such weeping from the eyes is also seen in other species when distressed, notably elephants and water buffalo.
Dogs who seem to cry a lot, especially small, fluffy breeds, should see a veterinarian because they could have chronic and potentially serious eye disease.
(Send all mail to firstname.lastname@example.org or to Dr. Michael Fox in care of Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.
Visit Dr. Fox’s website at DrFoxOneHealth.com.)