Ask the Vet: Ear Mites Contagious to Pets, Not People

December 19, 2020 Updated: December 19, 2020

Q: My new kitten Nala has ear mites, for which my veterinarian prescribed treatment. I know from reading your column that some animal parasites also infect people. Can Nala’s ear mites jump to me? What about my other cat?

A: Ear mites, the most common cause of ear infections in cats, are highly contagious among cats and dogs, particularly kittens and puppies. Ear mites prefer pets, so it’s unlikely Nala’s will venture into your ears.

Ear mites live in the cat’s ear canals, where they feed on ear wax and surface skin cells. Sometimes, the mites wander out of the ears to the nearby head and trunk.

Clinical signs include ear scratching, head shaking, and inflammation of the cat’s ears. The ear canals of cats with ear mites harbor debris that resembles coffee grounds. The black debris consists of the mites, their excrement, mite eggs, blood, and wax.

Diagnosis is made by examining the debris under the microscope and seeing the mites crawling through it.

It’s exceedingly rare for a cat’s ear mites to invade a human ear. However, a research-minded veterinarian conducted an experiment on himself, transferring ear mites from a cat’s ear to his own. In a veterinary journal article titled “Of Mites and Man,” he described the crunching sound of the mites feeding, the itchiness, the debris, and his temporarily muffled hearing.

Many products applied to the cat’s ear canals or skin quickly kill ear mites. Several of the medications also protect cats from additional parasites, including fleas, ticks, heartworms, roundworms, and hookworms. Since ear mites are easily transmitted from one cat to another, ask your veterinarian whether one of these products is right for your other cat.

Q: Henry, my young retriever mix, almost died after chewing a bottle of Gorilla Glue. It didn’t seem that he’d ingested much, but when he started vomiting, I took him to his veterinarian. She X-rayed his abdomen and found a large, solid mass of expanded glue completely filling his stomach.

If he hadn’t had immediate surgery, Henry would have died a painful death. Please warn your readers that sometimes what we think is innocuous can be deadly.

A: Your story will surely save lives.

Many glues, including some made by Gorilla Glue, Elmer’s, and other companies, contain diphenylmethane diisocyanate, often referred to as MDI, that swells to fill cracks.

Unfortunately, when a liquid glue that contains MDI is ingested, the warm, moist, acidic environment of the stomach quickly expands the glue into a large, hard polyurethane foam many times its original volume—and much bigger than it would be in air.

The hard foam blocks the gastrointestinal tract and causes retching, abdominal pain, loss of appetite, lethargy, and, sometimes, a distended abdomen. It can even rupture the stomach.

Since the body can’t digest the polyurethane foam mass, and it’s too big to be vomited, it must be removed through immediate surgery.

Super Glue, Krazy Glue, and other quick-setting glues that contain cyanoacrylate also pose a risk to pets. Though they don’t expand, they can adhere body parts to one another.

So, it’s important to securely store all glues and other chemicals where pets—especially curious dogs like Henry—can’t reach them.

Lee Pickett, VMD, practices companion animal medicine in North Carolina. Contact her at AskTheVet.pet. Copyright 2020 Lee Pickett, VMD. Distributed by Creators.com.