I have tremendous respect for service dogs. Guide dogs for blind people were the pioneers of the service dog world, but they are hardly alone. Dogs can also be trained to assist people who have hearing deficits and Parkinson’s disease. They can alert people with diabetes that their blood sugar is low, and they can warn epileptics of impending seizures.

More controversially, service dogs sometimes assist people with non-physical disabilities. I have had clients tell me, for instance, that they suffer from agoraphobia. They suffer severe panic attacks when they leave the house — unless their dog is with them. Does their dog therefore qualify, officially, as a service dog?

From my perspective, the answer is that it’s none of my business. My job is to work to keep animals healthy whether they are service dogs or not.

The definition of a service dog is not up to me. And, on the few occasions when clients have asked me for a letter describing their animal as a service dog, I have demurred and referred them to their physicians, whose job it is to determine whether a dog qualifies as a service animal.

I live in San Francisco, a city known for its beauty and its eccentricity. Over the past several years it appears that a number of physicians have been quite liberal in writing letters for owners of dogs (and cats, birds, and snakes) who wish to have their animals officially sanctioned as service animals.

However, that practice appears to be on the verge of a backlash. Some physicians are taking umbrage at what they see as an abuse of the service animal label. Consider a recent column in the San Francisco Chronicle (and on SFGate) by Dr. Laura Davies. The column is titled, “Pets don’t meet definition of therapy animals.”

Dr. Davies is a psychiatrist. In the column she describes an incident in which a patient asked for help having her cat labeled as a service animal. The request was inspired by the fact that patient lived in an apartment that did not allow cats. The patient was hoping to use the service animal label to circumvent the rule. Dr. Davies viewed this as an abuse of the system.

The column went on to offer information that was news to me. The U.S. Department of Justice has an official definition for service animals. Dr. Davies writes, “In a clarification of the Americans with Disabilities Act, the U.S. Department of Justice said in March 2011 that only dogs — not cats, birds, or snakes — are recognized as service animals and that ‘a service animal is a dog that is individually trained to do work or perform tasks for a person with a disability. … [D]ogs whose sole function is to provide comfort or emotional support do not qualify as service animals under the ADA.'”

The column points out that overusing the service animal label reduces the status of “true” service dogs, and that a dog who prevents a panic attack in its owner might well inspire a panic attack (or allergic reaction) in someone else. These points are reasonable, but in my opinion they are not especially sympathetic coming from someone whose role in life is to ease the psychological pain of people in need.

After that, the column in my opinion veers wildly off course. Dr. Davies invokes zoonoses (diseases that can be spread from people to animals and vice versa) as a reason not to classify animals as service dogs.

Physicians often seem to have an academic understanding of the concept of zoonoses, but their real-world familiarity with the disorders can be unrealistic. And their invocations of zoonotic threats often seem unnecessarily sensationalistic. Consider the following quote from Dr. Davies’ column, with my thoughts in bold italic.

“Dogs also can carry diseases. Human noroviruses, which cause most of the world’s diarrhea, are carried by dogs. True, but dogs aren’t a common source of norovirus infection; rather, we should blame people who don’t properly wash their hands after using the toilet. E. coli, which also causes bladder infections, is often shared between family members and dogs. E. coli resides in the intestines of every mammal. Again, poor human hygiene causes the overwhelming majority of intestinal disease. When E. coli causes bladder infections, the source is almost always, or perhaps simply always, E. coli from the person’s own intestines.

“MRSA, a dangerous microbe resistant to antibiotics, is also shared among pets and humans. Yes, but transmission appears to be very one-sided: people usually contract MRSA in hospitals and then give it to dogs; dogs don’t usually give it to people. Dogs can also be infected with bird flu. But there is no evidence whatsoever that they can transmit it to people. And by the way, no case of the dreaded H5N1 bird flu has ever been confirmed in North America. There are 30 to 40 diseases that dogs and cats transmit to humans. And there are hundreds or thousands of diseases that humans can transmit to each other. Is contact with other humans therefore dangerous? They can be transmitted through the air, by touch, or exposure to urine or feces. They can also contaminate the water and soil.”

Yes, there are diseases that can spread between pets and people. Ringworm, toxoplasmosis, and toxocariasis appear to pose the biggest threats, and those threats are small. But service animals — whether properly labeled as such or not — are not likely to spread these diseases. Healthy dogs and cats who receive regular broad spectrum deworming medications pose minimal threat to humans. This is true of pets and service dogs alike.

When you dine at a restaurant, fly on a plane, or step out of your house for any reason, your health is at risk. But it’s not because of the service animals or pets you might encounter. The real threats are sniffling toddlers, sneezing commuters, and cooks who haven’t washed their hands.

Other stories by Dr. Eric Barchas:

• I Hear Gurgling Sounds in My Dog’s Stomach; Should I Worry?
• What Causes Seizures in Dogs and How Should They Be Treated?
• 11 Hazardous Items to Ban from Your Home if You Have a Dog

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