Dear Doctor - April 2015
Letters to Tufts Veterinarians
Ebola transmission from dog to person
Q The Ebola scare seems to have died down for now, but I was wondering whether it’s possible for a person to get the illness from a dog?
Winter Haven, Florida
Dear Ms. Charles,
AThe chances are infinitesimally small. The American Veterinary Medical Association, or AVMA, says that “precautionary measures by Spanish health officials to euthanize the dog of an exposed healthcare worker” have “raised questions and concerns among veterinarians and the public alike,” but “there have been no reports of dogs…becoming sick with Ebola or of being able to spread the virus to people or animals. Even in areas of Africa where Ebola is present, there have been no reports of dogs or cats becoming sick with the virus.”
Furthermore, says the AVMA, the “chances of a dog being exposed to Ebola virus in the U.S. are very low. Exposure requires close contact with bodily fluids of a person with symptoms of Ebola infection,” for instance, urine, saliva, sweat, vomit, breast milk, or semen. Yes, it’s important for people symptomatic with the disease to avoid contact with animals to the extent possible, the organization cautions. It is known that nonhuman primates and fruit bats are susceptible to Ebola and capable of spreading the virus. But, the AVMA says, we do not even know at this point whether a dog’s body or fur can transmit Ebola to people. Not every disease can jump from one species to any other.
The Centers for Disease Control and Prevention are also not alarmed. They say “there is limited evidence that dogs can become infected with Ebola virus, but “no evidence that they develop disease.” In other words, on the list of things that should concern you about your pet dog, catching Ebola virus from him or her should be way, way down — or not there at all.
Cat fight? Dog fight? Cat-dog fight?
Q We are thinking of adding a cat to our family but are not sure how our four-year-old St. Bernard, Beethoven, will react. If he would absolutely hate it, we would forego adding a feline to the family.
Jamaica Plain, Massachusetts
Dear Mr. Patch,
AIt’s impossible to say ahead of time whether a particular dog and a particular cat are going to get along. It’s definitely not true that all dogs and cats hate each other — it’s not truly a Tom and Jerry world. But so much depends on the age of the two animals, their relative energy levels, and their personalities. A dog with a high prey drive and lots and lots of energy could potentially make life miserable for a cat. And a cat whose approach to life is “Scratch first, ask questions later” could make life miserable for a dog. Add crotchety-ness into the mix on either side, and the results could be a never-ending inter-species battle.
On the other hand, if Beethoven is a sweet-tempered giant whose mission in life is to get along, it could work out fine. When you bring the cat home, keep the dog on a leash at first so that neither one strikes out in defensiveness. And make them both feel good by speaking cooingly and encouragingly to them, petting them plenty, and providing delectable morsels of food. If need be, keep them in separate rooms for a couple of days.
For added safety, arrange escape routes and hiding places for the cat so he always has a chance to get away. Cats don’t always want to flee from danger. Sometimes, Greta Garbo-style, they simply “vant to be alone.” That said, we’ve known plenty of families where the dog and cat ended up happily snuggling with each other — or at least blithely ignoring each other. In almost all cases, they get the hang of each other’s presence.
The dog won’t play with toys
Q We’ve had a four-year-old, 14½-pound Yorkie for a year. He’s a lovely little guy, but he doesn’t play with any toys, with us or alone. We finally got him to chew on a hard store-bought bone a little bit — as long as we put a small amount of peanut butter in it. He is currently on anti-anxiety medication. I feel he would eliminate some of his anxiety if he were occupied with some kind of toy. Will he ever play with any or is he destined to sleep most of his waking hours? He's not a yappy small dog and talks to us only when he's hungry or just to “talk” at times, which is real cute. I should note that he does like to chase and bounce on our hand when we move around under a blanket or towel. We would like him to play with a toy, though. Any suggestions?
Sagamore Hills, Ohio
Dear Ms. Hart,
AThe first thing that jumps out at us is that your dog is on anti-anxiety medication and sleeps “most of his waking hours.” Anti-anxiety drugs from Valium to Xanax to Prozac can make a dog (or person) unusually sleepy if the dose is too high, so you’ll want to make sure with your pet’s veterinarian that the dose your little guy is on is right for him and also that he has no medical condition that would make him unduly tired.
As far as toys, it’s not important that a dog plays with toys per se. What’s important is that he remains active and stimulated. If objects with food get him going, so be it. Tufts animal behaviorist Stephanie Borns-Weil, DVM, particularly likes Pipolino. “It’s like a tube with wheels on the sides,” she says. “You put the kibble in and the dog chases it up and down trying to get the food to dispense.” There are other food puzzle toys as well. Also, since your dog likes to go for your hand under a blanket, try doggie pull toys. He may like the movement, the lure. Clicker training may work, too — anything to gain his interest and keep him engaged.
The dog’s nose changes color with the seasons
QMy dog’s nose is black in the summer but turns pink in the winter. Why is that? Is it something I should be concerned about?
Shore View, Minnesota
Dear Ms. Larson,
AThe reason for the change in nose color is unknown, although some have speculated that the periodic depigmentation is a consequence of different activities of the enzyme tyrosine, which is responsible for the synthesis of melanin — skin and hair pigment. Affected dogs might have a variant of the enzyme that is less active during the winter months, either because of reduced temperatures or a reduction in the amount of daylight. But that’s just a hypothesis. Whatever the reason, the condition, often referred to as “snow nose” or “winter nose,” is harmless — a cosmetic issue only — and nothing to worry about. It is relatively common in Siberian huskies, golden retrievers, Labrador retrievers, and Bernese mountain dogs and may also be seen in other breeds, albeit less frequently. The breed predisposition suggests a strong genetic component.
It is also nothing to worry about if your dog’s nose lightens with age, with no back and forth. The cause of that, too, is unknown but is probably just some kind of age-related change — likely a consequence of a genetic component combined with an environmental trigger, says Tufts Cummings School veterinary dermatologist Lluis Ferrer, DVM, PhD, DECVD.
Note that a dog’s nose color to begin with is indeed genetically determined, just like hair color, and can range from black to pink to liver-colored to the same color as the animal’s coat. All are normal. What’s not normal is if the nose changes color and the difference is not related to the season or aging. Sometimes it will lose pigment during an illness or trauma but then return to normal upon healing. Dermatitis can also lead to color changes. As an example, some dogs are sensitive to the materials used to make plastic food bowls, and the continued irritation causes the nose to turn pink. The lips will likely become inflamed as well. Switching to stainless steel utensils solves the problem.
You also want to make sure that only the nose is affected — not the lips, foot pads, eyelids, claws, or any part of the hair coat, Dr. Ferrer says. The nose depigmentation should also be symmetrical, with no lesions — no changes in the nose’s surface or texture.
Consider that the immune disease vitiligo, in which antibodies are formed against pigment-containing cells, can cause white patches on parts of the body other than the nose. And loss of nose pigment along with erosions or “crusts” on the nose’s surface can be the sign of a relatively severe inflammatory disease such as lupus.
Thus, if your dog’s nose changes color with accompanying blistering, dryness, or other texture changes, and if he seems uncomfortable around his nose, take him to the veterinarian to see if he has a condition that can and should be treated. But if his nose changes color but otherwise looks normal, and everything else about his mood and activity level seems the same as usual, you probably have nothing to worry about.
Do protect a pink or other-light colored nose from the sun with sunscreen, however. A pink nose can burn and blister — it is much more sensitive to solar radiation — and puts a dog at a higher risk for the development of cancer.