I’m going to talk about something scary today. Not an alien life form but a very real live virus called rabies. Rabies didn’t die out with Old Yeller – it is still very much with us, and definitely present in the wildlife of Merced County. In fact, Merced is considered an endemic area for the disease. We have positive cases every year! In the 30 plus years I have lived and worked here, I have watched both the Public Health Department and Animal Control cooperate to monitor Rabies positive cases turned in to the County. They map where the rabid animals were discovered, watching for “hot spots” of possible contagion in the wildlife. Positive rabid bats and skunks have been identified, often after a dog or cat has carried it into the house or killed it.

     But what about the animals that just quietly die in the wild, that may be carriers of the disease? This, of course, is how it is spread. Consider: Rabies virus enters the body through a direct bite or contact with the mucous membranes (eyes, mouth, nose). Once there, it slowly spreads into the nervous system, eventually reaching the brain. There is NO CURE for the disease at this point. In fact, only because the virus multiplies and spreads so slowly is it possible for post-exposure immunization to work and save human lives. Rabies is diagnosed after the brain of the suspect animal has been inspected. There is no way to diagnose the disease in a living patient.

     California is considered to have a high incidence of cases – over 400 cases in wildlife reported annually. Skunks and bats are the most frequent wildlife involved, but other carnivores such as  raccoons, foxes, coyotes and bobcats are often positive.

     Each year one or two cases of human rabies is reported in the United States. Since 2002, 21 of 24 reported human rabies cases in the US were linked to bats, per the Center for Disease Control (CDC). July 24, 2013 a young girl was bitten by a rabid bat at the Oakland Zoo- it was not an exhibit animal, just local wildlife. She received post-exposure immunization and is fine. Easter in Bakersfield, California of 2012 was grim for the family whose pet cat bit their child, after itself contracting rabies from area bats.

     In June, 2011 an 8 year old girl from Willow Creek, California actually survived the disease after intensive treatment at UC Davis’s Childrens Hospital. She is only the third person in the US to survive rabies without receiving the post-bite immunizations. Most people die or become vegetables. In countries where vaccination vigilance is not as high as the United States, rabies is a serious threat : 60,000 people die from this entirely preventable disease every year! Three “islands” are isolated enough to have no rabies : Hawaii, England and Australia. Travelling with pets to these places is a complicated process as they strive to remain rabies free, protecting people and their indigenous or native wildlife from sure death.

     Because wildlife cannot be vaccinated against Rabies, your FIRST LINE OF DEFENSE is to vaccinate your pets, the carnivores at highest risk of coming in contact with wildlife. ALL DOGS and CATS should be vaccinated against rabies. And you should never approach wildlife, especially when they seem sick.

     If your dog or cat is bitten by a bat or suspect carnivore that isn’t available for brain examination it is presumed exposed to a rabid animal. If the bat or skunk is confirmed positive and rabid and the dog or cat is NOT current with rabies vaccination protection it may be recommended that it be immediately destroyed. If the pet is current on vaccination, by law it will still be isolated for anywhere from 10 days to 6 months, depending on the individual circumstances of the case.

     If a human is bitten, whether it be a pet or a stray dog or cat, or any wildlife, it should immediately be reported to a physician. If the animal is available, it will be quarantined or its’ brain will be examined to check for rabies. The type of bite, animal involved, vaccination history and other factors will determine the recommendations made by your physician and public health authorities.

      This is where your money for those darned rabies licenses go. This is what it’s all about. The message : Vaccinate your pets against rabies. It’s the law – and it’s a good one!

Christine B. McFadden, DVM



     Moonshadow gently waved his tail from side to side, tongue pink as he greeted us. The older black lab moved with a stately grace across the exam room, a gentle cough escaping from his throat. “There, did you hear that? Why is he coughing like that?”, his owner queried anxiously. I stared down at him, mind running through possibilities. Moonshadow was old, so I had to put cancer on the list. Not a happy place to start. I said nothing as I began a full exam, checking out his teeth, moving over areas where lymph nodes lurked, probing his tummy, riffling through his fur. Moonshadow cooperated with everything, seeming to enjoy it all as one big petting fest. I pulled out my stethoscope and listened carefully to his chest, timing his heart rate and listening to his lungs expand and contract with each breath. A lot of times you don’t hear much listening to healthy lungs, maybe a quiet whoosh. Today I was hearing crackles and rales, sort of like Rice Krispy cereal when you first pour the milk on. Not a good thing to hear. I stood up from the floor where I’d been kneeling at Moonshadow’s side. He side-swiped me with a lick of appreciation, then coughed gently with the extra effort. His owner, in her late twenties, shifted from foot to foot anxiously. “We’ve been through so much together. He’s travelled across the country with me.” Her voice trailed off, tears threatening. Her dog walked over to her and pushed his head up under her hand.

     I asked to run a blood panel and take a set of chest x-rays. The x-rays would show me any masses in his chest that could be cancerous or might point to an odd disease like the fungal infection Valley Fever. I could evaluate his heart size and shape and find markers for other lung diseases. The bloodwork would check for signs of infection, diabetes, thyroid disorders and see if his liver and kidneys were functioning ok. Not much point in making a diagnosis of one problem and later finding out that my patient’s renal function was toast. Obtaining a complete picture up front was in the best interests of my patient so I could help him – or know that I couldn’t, should that be the case.

     One of the blood tests was for Heartworm, Dirofilaria immitis, a long spaghetti-like worm that lives in the blood stream, bobbing around through little capillaries and veins as larvae until they eventually grow up and take up residence in the lungs and heart. There can a fistful of worms clogging the heart. Nothing microscopic about it – unfortunately, the patient is usually dead when you get to see it that graphically.

     Heartworm goes through one of its life stages in the mosquito. It is when the mosquito bites your dog, sucking out a bit of blood (the mosquito’s meal) that it injects the microscopic larval form of Dirofilaria into your pets’ bloodstream. If you give your dog the heartworm preventative EACH MONTH it kills off all first-stage larvae encountered and the story ends there. If your dog isn’t protected by a heartworm preventative, or you forget to give it for a couple weeks (even if you re-start it and get back on track), then there is a window of opportunity for the first-stage larvae to grow on to the second stage and into the adult worms living in the chest. The whole process from mosquito bite to worms clogging the lungs and heart can take up to 2 years. The symptoms your pet shows may range from something mild like restless sleeping to wheezing to full out coughing and heart failure.

      Todays’ tests are very sophisticated, requiring only a few drops of blood to detect antigen, the bodies’ response to invasion by a foreign invader, in this case the heart worm. If your dog does test positive for heartworm, a second test is done to look for actual microfilaria larvae circulating in the blood, which helps stage the disease progression and predict the prognosis for your pets chances of beating this disease.

     Is there a treatment for dogs that have heartworm? Yes, an injectable form of arsenic. Can some dogs die from the treatment or get very sick from it? Yes. Does the treatment work 100% all the time? No. Once a dog has had heartworm and been successfully treated do its lungs go back to normal? It depends. Sometimes. Can cats get heartworm? Yes, statistically 5-10% as often as the dogs in a given area of California.

     In February 2015 there were two (2) cases of heartworm diagnosed in local dogs : a little Yorkie in Merced and a medium sized dog that lives in Atwater. Both are house pets and neither has ever travelled outside of town. For years we have known that pets that travel to the foothills, such as Mariposa or Sonora, are at very high risk; also the Delta area of Stockton. Most of the United States is infiltrated, so ALL travelling dogs and cats should be on monthly preventative. Heartworm is HERE in Merced County. Most dogs can be protected for less than $100 a year. Talk to your veterinarian about the best choices for your pet and family.

     And Moonshadow? He tolerated the arsenic treatments. His lungs were permanently damaged and he needed medicine for the rest of his life to keep the post-heartworm immune reaction under control. He was a dog that appreciated everything done for him and gave another two years of love to all he met in his journey through life.


Christine B. McFadden, DVM

Valley Animal Hospital, Merced

To Spay Or Not

     So you think your dog is cute and your friends wish they had one just like yours? Or you think it would be good for your children to witness a live birth? Or you paid money for a dog “with papers” and now it’s time to recoup the investment? You can breed it yourself and make a fortune (no fortune, of course, if the bitch requires a C-Section to deliver, or if you have the puppies examined and vaccinated, or heaven forbid they don’t sell quickly and you have to start feeding them). Yes, mutt or purebred, you have talked yourself into breeding your pet.

     Wait a minute. Please. Just because your pet is cute doesn’t mean its progeny will be equally attractive in looks or temperament (do you follow Hollywood?). And those friends who were just WAITING to get a dog often find it inconvenient when the time comes and decide to “wait till the next litter”. And why is it that you want your kids to experience the birth, but you fail to include them in the rest of the story – the ultimate Reality Show where you find out that half of the litter is not expected to stay in its original home? Should you tell your children to choose their favorite, then “kiss the rest goodbye”? Do you know that 25 % of the dogs turned in to Animal Shelters are purebred? That you can spay or neuter your dog for less than it costs to raise a litter of puppies? That HUNDREDS of dogs are euthanized every month, not just here in Merced County, but every city and county in the United States, because we would be over-run with stray and unwanted pets if we didn’t?


Start with one female dog and let’s do the math (as the Arizona Humane Society did years ago):

In her first year she produces 4 pups, 2 of them females (4 total)

Second year production of first and second generation females is 12 pups, 6 female (12)

Third year production of 3 generations of females is 36 pups, 18 females (36)

Fourth year production of four generations of females is 108 pups, 54 females (108)

Fifth year production of five generations of females is 324 pups, 162 females (324)

Sixth year production of 6 generations of females is 972 pups, 486 females (972)

Seventh year production is 2,916 puppies…..


If you think there is a population problem in the world, it does not even compare to the population explosion in the pet world!


Christine McFadden, DVM

Valley Animal Hospital, Merced