Itchy pets, perplexed vets: It’s unclear whether oak leaf mites are to blame

Linda Morales noticed that her shih tzu, Sofie, has been scratching and biting at her fur a lot lately — significantly more than her cocker spaniels Paco, Coco and Rico.

When news broke this week that this could be another bad year for bites related to the oak leaf itch mites, Morales couldn’t help but wonder if Sofie’s discomfort was caused by such a bite. In humans, the mites’ bites leave persistent itchy red marks that sometimes have fluid-filled centers.

“I wondered if there was a connection,” said Morales, who lets her dogs outside into her yard frequently. “Oak mites — I never heard of that.”

With two big old oak trees in her yard — one in the front and one in the back — and others in her Kansas City, North, neighborhood, she was curious if mites might have an effect on animals.

“We don’t really know, unfortunately, whether dogs and cats are attacked by these little guys,” said Michelle LeRoy, a dermatology associate with Veterinary Allergy & Dermatology Clinic in Overland Park.

“They are certainly a nuisance for people, but for dogs and cats, we haven’t necessary seen the exact sort of lesions that people get. But we are still kind of learning about whether they do affect pets.”

Knowledge of the microscopic mites is relatively new. The first recognition of the mite in the United States was in the autumn of 2004 in Kansas. The mites feed on larvae found in galls on the leaves of oak trees. Once done feeding in the fall, they exit the gall and drop or become airborne. That’s how they get on people and pets.

Most people don’t know when they are bitten by mites. By the time welts start forming, the mites have likely moved on. The very itchy bites, however, can linger for up to two weeks.

“People don’t get really bit on the head or scalp from those bites very often from what we can tell,” LeRoy said. “So we wonder if perhaps there’s some protective effects from the hair coat.”

Gonzalo Erdozain, a veterinarian with Kansas City Veterinary Care in the Waldo area, said the question about whether pets are affected by the mites has become a common one recently.

“Unfortunately, we don’t have any published data that would suggest or prove that the oak itch mites actually will bite our pets,” he said. “If, assuming they could bite our pets, it would be something you would see on pets who go outdoors, particularly those who get under infected trees.”

Erdozain said that they do see an increased caseload of itchy pets this time of year.

“Usually it starts two to three weeks before Labor Day — so late summer or early fall,” he said. “We attribute that to patients of ours that have seasonal allergies.”

Fleas also are a common cause of itchiness among both indoor and outdoor pets, as well as other mites that are known to affect pets.

Because there is no proven medication that would prevent or kill the itch mite, Erdozain advised pet owners to continue with the flea and tick prevention so those could be ruled out as a possible cause for itchy pets.

He also suggested limiting the pets exposures to the trees and leaves that possibly have the mites.

If pets are showing discomfort from itchiness, Erdozain advised owners to seek immediate care from their vet to prevent secondary infection and to determine the cause and proper treatment.

For now, uncertainty remains whether oak leaf itch mites bite pets.

“My boss and I would love to demonstrate whether that is true or not and if so write it up for the literature,” LeRoy said. “But at this point, we haven’t seen anything, even last year, that made us say, ‘Hey, this is most likely exclusively oak mite bites to this pet.’ ”

This story was originally published October 1, 2016 at 11:00 AM.