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Are there natural ways to prevent heartworms?

I’d like to find a natural way to protect my pets from heartworms. What are my options?
This is a valid question and one veterinarians frequently hear. Certainly, drug-free strategies can help reduce the risk of heartworm transmission to a dog or cat. Because heartworms are spread by mosquitoes, keeping pets indoors overnight and avoiding walks at dusk or dawn when mosquitoes may be feeding can help prevent exposure to mosquitoes that could be carrying heartworms. Eliminating standing water close to your home that could serve as mosquito breeding grounds is also recommended. Finally, natural repellents such as Neem oil and CedarCide may help diminish the chances that pets will be bitten by infected mosquitoes; however, Neem oil products should be used with caution in cats.

Unfortunately, mosquito control is not enough. While the risk of heartworm exposure can be reduced with these strategies, it can’t be eliminated.

To give pets the best chance of being protected, the American Heartworm Society recommends yearround use of U.S. Food and Drug Administration (FDA)-approved heartworm preventives.

Here’s why:

  • It only takes one bite from an infected mosquito to transmit heartworms to a dog or cat.
  • Ensuring that your pet is never bitten by a mosquito is virtually impossible. Dogs need exercise—plus most go outside for bathroom breaks.
  • Indoor cats aren’t completely shielded either. In fact, a heartworm study showed that 1 in 4 cats infected were indoor cats. Why? Mosquitoes can sneak inside and often lurk in doorways and breezeways. Once indoors, mosquitoes see your pet as the source of a tasty blood meal.

To give pets the best chance of being protected, the American Heartworm Society recommends year-round use of U.S. Food and Drug Administration (FDA)-approved heartworm preventives. While you may have seen websites that promote nosodes and herbal preventives, none of these products has been proven or FDA-approved to prevent heartworms in pets—nor do respected alternative-therapy veterinarians endorse their use.

I don’t like the idea of giving my pet a drug month after month. Is it safe?
This concern is understandable, but you can feel confident that keeping pets on approved heartworm preventives currently is the best—and safest—way to protect their health. The FDA requires extensive testing to confirm the effectiveness and safety of heartworm medications before approval, and monitors safety after the medications are on the market. It is also worth noting that the avermectin class of medications, to which heartworm preventives belong, are naturally occurring compounds that are generated as fermentation products of a soil-dwelling bacterium.

Some heartworm preventives protect only against heartworms, while others protect against everything from intestinal parasites to fleas and mites. Work with your veterinarian to determine what your pet needs—and doesn’t need.

A final thought: the biggest threat to your pets’ health is not protecting them from heartworm. Once infected, dogs must undergo a costly and potentially risky treatment regimen, and the damage left by the infection can be lifelong. Meanwhile, there is no approved heartworm treatment for cats. The best and safest alternative is year-round prevention.

Some heartworm preventives protect only against heartworms, while others protect against everything from intestinal parasites to fleas and mites.


Will Heartworm Preventives Protect My Pet?

Year-round administration of an approved preventive is your pet’s best defense against deadly heartworm disease. While some concerns have arisen in recent years about the potential for heartworms to become resistant to common heartworm medications, the facts do not indicate that you should stop using them. Instead, you should make sure you understand how you can best protect your pet.

How do preventives work?
Heartworm prevention medications are given monthly or at six-month intervals, depending on the product. These medications do not actually prevent pets from becoming infected with heartworm; they work by helping kill new, developing heartworms that have infected the pet between doses. Resistance occurs when a heartworm isn’t affected by the medication and matures into an adult. The result is heartworm infection.

Is resistance common?
Several research studies have confirmed that resistant worms can develop in dogs. However, there are no indications that resistance is common—nor is resistance increasing at a rapid rate. While reports have mostly been limited to the south-central United States, where heartworm infection is most prevalent, resistant heartworms could develop in other locations as well. Should heartworm infection result from the failure of a heartworm preventive, the infection can be successfully treated.

What should I do for my pet?
The most important step is to continue to give your dog or cat its heartworm medication faithfully. Approximately 1 million dogs in the U.S. are estimated to have heartworm disease, and the most common reason is failure to provide year-round prevention. Prevention offers the best protection available to pets and is effective in the vast majority of cases.

The other important step is to follow the American Heartworm Society (AHS) guidelines for heartworm prevention and treatment. Specific recommendations include the following:

  • Puppies and kittens should be started on a heartworm preventive as early as possible, no later than 8 weeks of age. Only use heartworm preventive medications approved for pets and prescribed by your veterinarian.
  • Give heartworm preventives as directed. Make sure your pet gets the right dose (no more, no less) for its weight and give the medication on schedule. Large-animal medications should never be administered as preventives.
  • Dogs and cats over 6 months of age put on heartworm preventive for the first time should be tested before dosing is started. Dogs should be tested a second time six months later and thereafter a minimum of once a year. Early detection provides the best opportunity for treatment success.
  • If your dog tests positive for heartworms, do not use unapproved therapies such as the “slow-kill” method, which is a term for using heartworm preventives alone as a treatment. This approach puts a pet’s health at risk and can actually increase the chances of developing resistance. It’s also essential to work closely with a veterinarian. Treatment includes the use of a prescription drug called melarsomine, which kills adult heartworms, as well as other medications.
  • Ask your veterinarian for recommendations on minimizing mosquito exposure, since mosquitoes spread heartworm.

The best offense against heartworm disease is a good defense. Follow AHS recommendations and Think 12: Give heartworm preventives 12 months a year and test your dog every 12 months.

What if My Cat Tests Positive

While many pet owners think heartworm disease only happens to dogs, cats are just as likely to be infected by mosquitoes. These infections are serious — and sometimes fatal — in both dogs and cats, but there are differences in the nature of the disease and in how it’s diagnosed and managed.

Because a cat is not an ideal host for heartworms, some infections resolve on their own, although these infections can leave cats with respiratory system damage. Heartworms in the circulatory system also affect the cat’s immune system and cause symptoms such as coughing, wheezing and difficulty breathing. Heartworms in cats may even migrate to other parts of the body, such as the brain, eye and spinal cord. Severe complications such as blood clots in the lungs and lung inflammation can result when the adult worms die in the cat’s body.

Diagnosing and managing heartworm disease in cats
While infected dogs may have 30 or more worms in their heart and lungs, cats usually have six or fewer — and may have just one or two. But while the severity of heartworm disease in dogs is related to the number of worms, in cats, just one or two worms can make a cat very ill. Diagnosis can be complicated, requiring a physical exam, an X-ray, a complete blood count and several kinds of blood tests. An ultrasound may also be performed.

Unfortunately, there is no approved drug therapy for heartworm infection in cats, and the drug used to treat infections in dogs is not safe for cats. Nevertheless, cats with heartworm disease can often be helped with good veterinary care. The goal is to stabilize your cat and determine a long-term management plan.

Here’s the plan of action you should expect if your cat tests positive for heartworm:

Monitor your cat
Heartworm-positive cats may experience spontaneous clearing of heartworms. If your cat is not showing signs of respiratory distress, but worms have been detected in the lungs, chest X-rays every six to twelve months may be recommended. If mild symptoms are noted, small doses of prednisone may be administered to help reduce inflammation.

Provide veterinary care
If the disease is severe, additional support may be necessary. Your veterinarian may recommend hospitalization in order to provide therapy, such as intravenous fluids, drugs to treat lung and heart symptoms, antibiotics, and general nursing care. In some cases, surgical removal of heartworms may be possible.

Maintain prevention
A cat that has developed heartworm disease has demonstrated that it is susceptible to heartworm infection, and both outdoor and indoor cats are at risk. It’s important to give your cat monthly heartworm preventives, which are available in both spot-on and pill form. Preventives keep new infections from developing if an infected mosquito bites your cat again. As a bonus, some preventives also protect cats against other parasites that can affect their health.

Heartworm disease is serious in cats, but many cases can be managed with good veterinary and home care. Meanwhile, healthy cats should be kept healthy with year-round heartworm prevention.

Welcoming a New Pet

Congratulations on your decision to bring a pet into your home. Whether you’re acquiring a puppy or kitten, or adopting an adult pet, you’re probably eager to learn more about proper care and feeding. The following tips can help you get off on the right foot with your new family member.

Veterinary care
Just as you require regular visits to your doctor to stay healthy, so does your pet. At a minimum, a veterinary visit should be a once-a-year event, and more frequent checkups may be needed. Regular exams are likely to include a thorough physical exam, a weigh-in, immunizations and parasite checks (a heartworm test and fecal exam). Blood tests and dental cleanings are also routine procedures.

Your new pet may be eyeing your plate with interest, but don’t give in! Pets shouldn’t eat like people. Cats are carnivores, so they need plenty of protein in their diets — roughly twice the percentage that you do — and they need it in the form of meat, poultry or fish. And while your dog, like you, is an omnivore, that doesn’t mean he should share your meals. A food formulated especially for dogs is much better, and treats should make up no more than 10 percent of a dog’s caloric intake.

Parasite prevention
You’ve probably heard of pests such as heartworm, fleas, ticks and intestinal parasites, but understanding how and when to prevent them is a different matter. Both dogs and cats can become infected with heartworms, whether they spend their time indoors or out. Because mosquitoes spread heartworms, dogs and cats need protection year-round, thanks to a mosquito’s ability to survive in a variety of environments. A bonus is that many heartworm preventives also protect pets against other internal parasites. Meanwhile, fleas and ticks live on the outside of pets. Not only are these pests unwelcome houseguests, they also can cause allergies and spread diseases to your pet and your family. Ask your veterinarian how you can keep your pet protected from all these parasites.

Most of us wouldn’t dream of letting a day go by without a shower or bath. But daily bathing is unnecessary for pets, and can dry out their skin and hair. Most dogs are fine with a bath every three months, unless they get extra dirty or have silky hair. Cats usually keep themselves clean without any help from you, although brushing long-haired cats on a regular basis is advised to keep their fur tanglefree and help prevent hairballs.

Communicating with your pet
Dogs and cats relate to their owners in different ways. As pack animals, dogs expect you to lead their pack and to give them rules to follow. Cats attach to their people as social partners, using affectionate behaviors, such as purring, kneading and rubbing against you to show their affection. Bringing a pet into your home is one of the greatest joys in life, but it means more responsibilities. Understanding your pet’s behavior, as well as the do’s and don’ts of pet health care, will help make your bond with your pet a lasting one.

The Truth About Cats and Dogs

Heartworm disease is a very serious disease in both cats and dogs, but the unique physiology of each species means that it is really two very different diseases. As you learn about the similarities and differences here, however, remember the bottom line: both dogs and cats need heartworm testing and year-round heartworm prevention.


Heartworm disease is a year-round health threat that has been diagnosed in all 50 states. Prevalence and risk Heartworm disease is a year-round health threat that has been diagnosed in all 50 states.
Dogs become infected through the bite of mosquitoes, which acquire heartworm larvae from infected dogs, coyotes, foxes and wolves. Transmission Cats become infected through the bite of mosquitoes, which acquire heartworm larvae from infected dogs, coyotes, foxes and wolves.
Heartworms in dogs grow to an average of 12 inches in length. Worms live 5-7 years. Heartworm characteristics Heartworms in cats are shorter than those in dogs, averaging 8-9 inches in length. Worms live 2-4 years.
Dogs are a natural heartworm host; heartworms that live inside a dog mature, mate and produce offspring. Host animal Cats are a susceptible heartworm host, but are more resistant than the dog. Most worms do not survive to be mature adults, but still cause damage.
Nearly 100% of dogs exposed to infective heartworm larvae become infected. Susceptibility Approximately 75% of cats exposed to infective heartworm larvae become infected.
The average number of heartworms in an infected dog is 14-20. It is not uncommon for a dog to have more than 50 worms. Worm numbers Most cats with infections have less than 6 heartworms; 1- to 2-worm infections are common.
Worms living in the heart, lungs and arteries cause an inflammatory response that results in blockages in blood vessels. The damage from heartworms can be permanent, affecting a dog’s health and quality of life. Heartworm disease tends to progress as worm numbers grow and cause damage to arteries and organs. Disease characteristics Cats are highly sensitive to heartworms and, unlike dogs, do not need to harbor adult worms to become ill. Heartworm larvae can trigger a severe immune reaction called heartworm associated respiratory disease (HARD); this syndrome occurs in an estimated 50% of heartworm infections in cats.
Symptoms in dogs usually start with a cough, which worsens as the disease progresses. Fatigue, difficulty breathing and weight loss are common in later stages. Ultimately, affected dogs can experience heart failure and death. Disease symptoms Cats develop an asthma-like lung disease with respiratory distress and chronic coughing or vomiting. In cats with adult worms, the death of just one worm can cause sudden death.
Heartworm is easily diagnosed in most dogs with a simple blood test. Testing is recommended before the dog is started on preventive, then annually thereafter. Diagnostic testing Heartworm in cats is difficult to diagnose with blood tests. Further testing, including x-rays, may be required to make a diagnosis. Blood tests are recommended before a cat is started on a preventive.
An FDA-approved medication is available to eliminate heartworms in dogs Treatment There is no approved treatment for heartworms in cats
An estimated 37% of dogs in the U.S. are on heartworm prevention.
The American Heartworm Society recommends year-round heartworm prevention.
Prevention is easy and highly effective!
Prevention Less than 5% of cats in the U.S. are on heartworm prevention.
The American Heartworm Society recommends year-round heartworm prevention. Prevention is easy and highly effective!


The DO's and DON'Ts of Heartworm Protection

Knowledge and proper care keep dogs heartworm-free.

DO have your veterinarian test your dog each year for heartworm infection. It takes roughly 6 months for an infection to be detected with a standard heartworm test, so if your dog becomes infected, this schedule helps ensure early diagnosis and treatment.

DON’T skip testing just because your dog is on year-round heartworm prevention. While this will likely keep him or her heartworm-free, if you miss a dose, are late with it—or your dog spits out or rubs off the medication—it could create an infection opportunity.

DO give your dog his or her heartworm preventive on time, every time. Whether you give a monthly pill or spot-on medication—or you visit your veterinarian for a semi-annual injection—being consistent is essential. Not only is your dog protected, but you stay in the prevention habit.

DON’T stop prevention just because you haven’t seen a mosquito lately. Heartworm preventives work retroactively, eliminating new infections that were transmitted months earlier. Rather than guessing at when it might be “safe,” keep your pet on prevention year-round.

DO make sure the product you rely on actually is a heartworm preventive. With so many parasite protection products on the market, it’s easy to get confused. Far too many people assume their flea and tick product is protecting their dog from heartworms when it isn’t.

DON’T forget that many heartworm pills and spot-on products protect against other parasites. Some protect pets from intestinal worms; others also protect against fleas and certain ticks and mites. Talk to your veterinarian about what product offers the protection your dog needs.

Think 12. Show your love for your pets by giving them 12 months of heartworm prevention and having them tested for heartworm every 12 months.

The DO's and DON'Ts of Feline Heartworm Protection

Prevention is the only way to keep cats heartworm-free.

DO give your cat his or her heartworm preventive on time, every time. Whether you prefer giving your kitty a monthly pill or administering a spot-on medication, being consistent is essential. Remember: no heartworm treatment is approved for use in cats (the medication approved for heartworm treatment in dogs is not safe for cats), so prevention is the ONLY option.

DON’T rely on “seasonal” heartworm prevention. Just because you haven’t seen a mosquito lately doesn’t mean you should stop protecting your cat. Heartworm preventives work retroactively, eliminating new infections that were transmitted months earlier. Rather than guessing at when it might be “safe,” keep your kitty on prevention year-round.

DO give heartworm preventives to all the cats in your household. The average number of cats in a U.S. household is 2.1, so you may need to double up when purchasing heartworm preventives. If you bring a kitten into your house, he or she should be on a heartworm preventive by 8 weeks of age (follow the product label).

DON’T skip heartworm prevention just because you have an “indoor” kitty. Heartworms are spread by mosquitoes, but outdoor cats aren’t the only cats at risk. Mosquitoes are sneaky and know how to come inside! In fact, 1 in 4 cases of heartworm infection in cats occurs in indoor kitties.

DO make sure the product you rely on actually is a heartworm preventive. With so many parasite protection products on the market, it’s easy to get confused. Far too many people assume their flea and tick product is protecting their cat from heartworms when it isn’t.

DON’T forget that many heartworm pills and spot-on products protect against other parasites. All heartworm preventives for cats prevent at least some intestinal worms, while others also protect against fleas, mites and additional worms. Talk to your veterinarian about what product offers the protection YOUR cat needs.

Think 12. Show your love for your pets by giving them 12 months of heartworm prevention and having them tested for heartworm every 12 months.

Should You "Winterize" Your Pet?

The arrival of autumn signals many changes in the household — switching from salads to soups, pulling sweaters out of storage, changing furnace filters. With pets, however, you may need to think as much about what you don’t change as what you do.

Don’t fall off the exercise wagon. With days getting shorter — and cooler — it can be tempting to skip your early morning or evening walk. But with more than half of all pets in the U.S. being overweight or obese, exercise is vital. A daily walk can rev the metabolism of both two- and four-legged walkers for hours.

Do ensure your pet is outfitted for cooler weather. Small, light-bodied dogs; those with very short hair; and older dogs with weakened immune systems are likely to need sweaters when venturing outside. And once truly cold and snowy weather sets in, dogs may require protective footwear to keep their paw pads from freezing.

Don’t assume that cooler weather eliminates the threat of diseases like heartworm, which are spread by infected mosquitoes. Mosquitoes have been known to survive well into the winter months, thanks to indoor havens and protected microclimates existing within larger, cooler climate zones. For this reason, the American Heartworm Society recommends year-round heartworm protection for both dogs and cats.

Do ensure your senior pet has a warm, draft-free place to sleep. Many older dogs and cats suffer from arthritis. Just as sore joints in people tend to feel worse in cold weather, the same is true for pets. A warm, cozy bed can make nights — and mornings — more comfortable.

Do be sensitive to your pets’ feelings if fall brings changes to your household. Just like people, pets can get depressed. If you’re missing a son or daughter who has moved away to start college or a job, chances are your family pet is also feeling the loss. Spending time with your pet and giving him an extra measure of cuddling and affection will help both of you feel better.

Puppies and Kittens Need Protection Too

Protect them from the start
Puppies and kittens may be the picture of health — but their risk of getting heartworm disease is equal to that of adult pets. That’s why the American Heartworm Society recommends that puppies and kittens be started on a heartworm preventive as early as the product label allows, and no later than 8 weeks of age. Heartworms are found in all 50 states, so every young pet is at risk.

Monitor growth — and dosage
The dosage of a heartworm medication is based on body weight, not age. Puppies and kittens grow rapidly in their first months of life, and the rate of growth — especially in dogs — varies widely from one breed to another. That means a young animal can gain enough weight to bump it from one dosage range to the next within a matter of weeks.

For example, a large-breed dog such as a German shepherd typically weighs about 17 pounds at 4 weeks of age. By 8 weeks of age, he’s likely to tip the scales at 29 to 30 pounds. That’s nearly a doubling of body weight in one short month. And for some heartworm medications, that could mean a change from one dosage size to another.

Remember that different breeds of dogs mature at different rates. Small dogs tend to reach maturity much sooner than large and giant dogs. The weight of a Great Dane puppy, for instance, may need to be monitored for much longer than that of a Chihuahua to ensure the heartworm preventive dosage is correct.

Make a plan with your veterinarian

  • You’re making the effort to protect your young pet from heartworm disease — go one step further and ask your veterinarian for advice about anticipating when a dosage change will be needed.
  • Check into buying one or two heartworm preventive tablets at a time rather than 6 months’ worth, if a dosage change is anticipated. (There is a sustained-release injectable preventive available for dogs 6 months of age or older.)
  • Bring your pet in for every scheduled well-puppy or well-kitten exam, so that you stay on top of all health issues, including heartworm protection.
  • Confirm you are giving the right heartworm preventive dosage by having your pet weighed at every visit.

Prevent so there’s no need to treat
Starting heartworm preventive as soon as possible is one of the most important steps you can take to help ensure a long, healthy life for your young pet.


Pets on the Go

If you do a little planning, it’s easy to travel with your pet. Whether it’s a weeklong getaway or your annual migration to escape the winter cold, you may be making plans to take a four-legged family member with you. Keeping your pet safe and healthy on the road is easy, but it does take some preparation. Consider these tips:

Consult your veterinarian. Start with a phone call to your pet’s veterinarian. He or she will provide valuable advice.

Ask yourself if it’s the best choice for your pet. The logistics of some trips might make it difficult to include your pet. Your veterinarian can help you decide if leaving your pet at home with a pet sitter or at your favorite kennel is a better option.

Check with your airline. If you’re flying, call your airline to find out the requirements for pet travel. Each airline has its own rules and regulations.

For travel by car, invest in a carrier. Your pet will appreciate having a safe haven while in transit and when arriving at a strange new destination. Add a favorite blanket or rug to provide a sense of familiarity. Another alternative is a pet safety harness that attaches to a seat belt.

Bring the comforts and routine of home. Travel bowls, plenty of pet food, a few favorite toys, supplies for clean-ups and all your pet’s medications are necessities, not luxuries. Bringing water from home can help prevent diarrhea. And don’t take a “vacation” from your pet’s health maintenance. Whether it’s a daily medication or a monthly preventive, don’t let travel disrupt his treatment schedule. You especially don’t want to miss administering heartworm, flea and tick preventives while you’re away from home.

Help your pet avoid motion sickness. Although you want to make sure your pet has access to water, don’t feed your pet right before departure. Restricting food can help prevent digestive upset while in transit. Also, if your pet isn’t used to traveling, getting your pet accustomed to car travel is important.

Inspect your new environment. Your ski chalet, beach house or hotel room may not be pet-proofed. Look for potential dangers, such as top-heavy furniture and weak door latches, to ensure your pet isn’t injured or can get loose. Keep holiday decorations, such as candles, plants and goodies out of reach.

Monitor your pet’s exploration of the new digs. Although you may enjoy settling into a new place, your pet might be stressed with the strangeness of it all. Let your pet acclimate for a few minutes before removing the leash or opening the carrier. Make sure your pet has an identifi cation tag or a microchip to ensure you can be contacted if your pet escapes.

Enjoy yourselves! Most important, relish this break from your busy, workaday life to spend some quality time with your pet.

No Crystal Ball

Why pets need year-round heartworm protection
If only veterinarians had a crystal ball that could reveal exactly when and where heartworm was going to pose a threat to every pet in the country, they could counsel pet owners accordingly. However, crystal balls are in short supply, and weather and environmental conditions that are conducive to heartworm transmission are impossible to predict. For example, who would have predicted that the winter of 2012 would be—as the U.S. National Climatic Data Center has confirmed—the fourth warmest winter in more than a century? Meanwhile, in the past six years, the U.S. has experienced the most extreme negative and positive temperatures on record.

Across the country — from east to west and north to south — balmy winter weather is creating ideal conditions for an early crop of mosquitoes. And for pets, mosquitoes are more than a nuisance; these pesky little blood-sucking beasts are responsible for transmitting deadly heartworm disease.

Heartworm: impossible to predict
A nationwide incidence survey conducted by the American Heartworm Society in 2010 confirmed that heartworm incidence and its risk factors are impossible to predict. Multiple variables, from microclimates to the presence of wildlife carriers, cause rates of infection to vary dramatically, even within communities. Because these factors are so variable, we never know when mosquitoes will emerge in the spring or how late into fall they’ll hang around.

Protect your pets
Heartworm is a serious disease that threatens the lives of infected dogs and cats. Fortunately, heartworm prevention is relatively inexpensive and easy to administer. And because neither you nor your veterinarian can predict when or where your pet might be exposed, the American Heartworm Society recommends that you Think 12: (1) get your pet tested every 12 months for heartworm and (2) give your pet heartworm preventive 12 months a year.

Think 12 and you won’t need a crystal ball!


Mosquitoes in Winter

In the dead of winter in parts of the country where the mercury drops below the freezing point and it snows often, owners are probably not seeing mosquitoes.

But that doesn’t mean the threat of heartworm disease goes into hibernation.

Preventing heartworm can be as important in the winter as it is in the summer.

  • Heartworm medicine works by killing the parasites that your pet picked up the previous month. If you stop giving it in the fall or early winter, the parasites might remain and cause an infection.
  • In many regions, the weather remains mild and mosquitoes continue to bite and cause heartworm disease.
  • If you live in a cold climate, but travel with your pet to warm places, you may expose your pet to the threat of heartworm infection.
  • Finally, getting the timing of when to stop and start giving heartworm medicine right is much more difficult than staying on a regular monthly schedule. And while prevention is inexpensive, treatment is not.

You may not see mosquitoes buzzing around in the middle of winter, but the threat of heartworm disease hasn’t disappeared.

Protect your pet — every month, all year round.

It Pays to Test: Why Your Dog Needs an Annual Heartworm Checkup

Spring, summer, winter or fall—your pets need year-round prevention to keep them free of deadly heartworms and other parasites. While an annual heartworm check-up with your veterinarian is one of the best moves you can make as a responsible pet owner, it’s helpful to understand why heartworm testing and examinations are important.

My dog was just tested for heartworm a year ago. Why does he need a test again so soon?
Your dog should have a heartworm test once a year to determine if he became infected with heartworms during the previous season. It takes months before a dog with heartworm will test positive on a heartworm test, so testing annually—usually at the time the prescription for his heartworm medication is being renewed—makes sense. As with many diseases, the earlier heartworm can be diagnosed, the better the chances he will recover. If heartworm disease in a dog goes undetected and untreated, the worms can cause progressive and potentially fatal damage to his arteries, heart and lungs.

If my dog is on continuous heartworm prevention, why does he need to be tested?
That’s a logical question if you’re a responsible owner who keeps your dog on heartworm prevention yearround. The reason for annual testing of dogs in this case is to ensure his prevention program is working. Heartworm medications are highly effective, but dogs can still become infected.

Why? A common reason is simple forgetfulness. Missing just one dose of a monthly medication—or giving it late—can leave a dog unprotected. Even if you do everything right and on time, it’s no guarantee. Some dogs spit out their heartworm pills when their owners aren’t looking. Others may vomit their pills or rub off a topical heartworm medication. Whatever the cause of missing or delaying a dose, any of these mishaps can put your dog at risk of heartworm infection.

I have several cats as well as a dog. Do my cats need heartworm protection too?
Like dogs, cats get heartworm disease. And while cats are not as easily infected as dogs, it only takes one or two heartworms to make a cat very sick. That’s why the American Heartworm Society recommends year-round protection for both dogs and cats.

Because heartworm disease in cats may or may not involve infection with adult worms, the diagnosis can be challenging. Veterinarians typically run heartworm blood tests on cats before putting them on medication the first time, but later rely on procedures such as chest x-ray or ultrasound to confirm diagnoses.

Remember, the best offense against heartworm disease is a good defense. Follow AHS recommendations and Think 12—give heartworm preventives 12 months a year and test your dog every 12 months.


Only Takes One Bite

The mosquito is a small but mighty pest that most of us encounter when the weather turns warm and we spend more time outdoors. And because fur doesn’t stop mosquitoes from biting cats and dogs, they get attacked, too. Unfortunately, there’s more at risk for pets from mosquito bites than the itching we endure. Because mosquitoes transmit heartworm disease, just one bite can be deadly to a pet.

1. How do dogs and cats get heartworm disease?

  • There’s only one way — through a mosquito bite. It cannot be spread from one pet to another.
  • Mosquitoes become infected by biting an animal that has the disease.
  • The infected mosquito then bites a dog or cat and passes microscopic, infective larvae to them.
  • If the pet is not on a heartworm preventive all year, the larvae mature and multiply, causing damage to the heart and lungs.

2. Is it true cats don’t get heartworm disease?

  • Cats can get heartworm disease from a mosquito bite, just like dogs. It is true that cats tend to have significantly fewer adult heartworms than dogs when infected, but the infection is no less serious.

3. Can indoor pets get heartworm disease?

  • Yes, mosquitoes frequently get inside our homes. It only takes one bite for a cat or dog to become infected, so any exposure to mosquitoes — inside or outside — puts a pet at risk.

4. How can I prevent my pet from getting heartworm disease?

  • The best way to prevent this potentially fatal disease is to use and keep your pet on preventive all year.
  • It’s also important to have your pet tested once a year.
  • Talk to your veterinarian if you have any questions about heartworm disease and how best to protect your pet.

Heartworm Testing 1-2-3

1. Why should I have my pet tested for heartworm?

  • Heartworm disease is a serious, progressive disease. The earlier it’s detected, the easier it is to treat.
  • There are often few, if any, signs of disease when a dog or cat is infected with heartworms, so detecting their presence with a heartworm test is important.

2. What is a heartworm test?

  • A heartworm test is simple and only requires a small blood sample from your pet.
  • A heartworm test works by detecting the presence of heartworm proteins.
  • The test may be read right at the clinic or sent out to a laboratory.
  • If a pet tests positive, further tests may be ordered.

3. When will my pet be tested for heartworm?

  • Yearly testing is the standard of care and is recommended by the American Heartworm Society.
  • If a pet is showing signs of heartworm disease, such as coughing or stress during exercise, your veterinarian may order a test.
  • A heartworm test may be part of screening before surgery to help reduce the risk of complications.
  • Your veterinarian may test your pet before giving heartworm medication for the first time.

Ask your veterinarian if you have additional questions about heartworm testing or the important role it plays in managing the health of your pet. And in addition to thinking about the 1-2-3 of testing, remember to “Think 12.”

  • Test for heartworm every 12 months.
  • Give heartworm preventive 12 months a year.

Further Reading
Heartworm Disease in Dogs. ©Heska
Heartworm Disease in Cats. ©Heska
Heartworm Disease in Dogs. ©Idexx Laboratories Laboratories 

Health Tips for Shelter Cat Adopters

Adopting a cat from a local animal shelter or rescue organization is a great way to save a life while gaining a loving companion. Just be sure you’re prepared to supply good health care along with lots of unconditional love. Cats in animal shelters have varied health histories—some arrive with a complete record of veterinary care, while others come in as strays with unknown histories. Because of this, it’s important to understand the basics of disease prevention and management.

If you’re considering adopting a shelter cat, consider the following questions:

  1. Why does my cat need veterinary care? Just like you, your cat needs regular physical examinations and preventive care. Routine veterinary visits can actually save money in the long run by catching signs of health conditions early, when intervention can be most effective.
  2. Who will be my cat’s veterinarian? If you don’t have a veterinarian in mind, ask the animal shelter staff for recommendations. Look for options such as cat-only practices and general practices that promote a cat-friendly or “fear-free” environment.
  3. What should I take to my cat’s first veterinary visit? Plan to take your newly adopted kitty to a veterinarian within the first week. Bring your cat’s health records (the shelter should supply these), so your new veterinarian can make decisions about disease testing and prevention. If you’ve adopted a kitten, be aware that you will be making frequent visits during the first year of life.
  4. Is my cat protected from parasites? “Inside” parasites such as heartworms and intestinal parasites are mostly out of sight, but shouldn’t be out of mind. While often associated with dogs, heartworms can infect cats, too, causing severe lung disease. Roundworms and hookworms, meanwhile, are fairly common in cats, and can even infect your human family. 
    A monthly heartworm preventive can protect your cat from both heartworms and intestinal worms. Depending on the product recommended by your veterinarian, your preventive may also protect your cat from pesky “outside” parasites, such as fleas, ticks and mites, which can spread discomfort and disease. Just be sure to administer the preventive year-round, even if your cat lives indoors. And remember: feline heartworm infection cannot be treated, so monthly prevention is vital.
  5. Will my cat be stressed? While your cat will adjust to his or her home in a matter of weeks, the transition can be stressful. Appetite loss is common, so continue feeding the food he or she was eating at the animal shelter, at least for awhile. Stress can also cause symptoms such as diarrhea. If this is an issue, your veterinarian may recommend a probiotic supplement or a medication to help manage the problem.

Finally, give your new kitty time to get used to the sounds and smells of your home. Start him or her up in a quiet room that’s off the beaten path. Stock the basics, such as food, fresh water, a litter box and a comfortable bed.

Congratulations on your new pet’s adoption! With the help of your veterinarian, you and your new kitty can look forward to many happy, healthy years together.

Get the Right Parasite Protection

Parasites come in many different species and forms and can live both inside and outside your pet. Some of the more common types of internal and external parasites include:

Internal parasites:
Intestinal (GI) worms

  • Roundworms
  • Hookworms
  • Tapeworms
  • Whipworms


  • Toxoplasma
  • Giardia

External parasites:

  • Deer tick
  • American dog tick
  • Brown dog tick


  • Sarcoptes (scabies)
  • Demodex
  • Ear mites

Know your pet’s parasite risk
The risk of your pet contracting any one type of parasite can vary, depending on:

  • Where you live (certain species of ticks, for instance, are much more prevalent in some locales that others),
  • Your pet’s environment (does she spend most of his time inside or outside; if outside, where?), and
  • Your pet’s lifestyle (for instance, do you and your pet travel or do lots of outdoor activities together? Is he frequently in contact with other pets?).

Some parasites are so prevalent and represent such a significant risk that prevention is a universal recommendation. For example, the risk of exposure to heartworm—which is spread by mosquitoes—is usually greater for a dog that spends its days outside than it is for an indoor cat that is only occasionally exposed to mosquitoes that come indoors. Nevertheless, both of these animals are at significant enough risk to warrant routine protection.

In addition, many parasites, such as roundworms and hookworms, can be transmitted to people as well; this is called zoonosis. Zoonotic parasites are especially a concern if you have young children or older adults either living or frequently visiting in the household, as their immune systems are not as strong as those of healthy adults. Protecting your pet can keep your family safe as well.

Use the right product(s)
Veterinarians report that pet owners frequently assume their pets are getting more parasite protection that they are because they simply don’t always understand what different products are for.

Some broad-spectrum products are effective against a number of different internal and external parasites, while others may be designed for only one or two pests—or even killing pests at specific stages of their life cycles. In this case, giving your pet the protection it requires will likely involve giving several different medications. For example, you may need to give one product for fleas, another for ticks and another for heartworms and intestinal parasites. The important thing: know the difference. Read the products’ label and follow your veterinarian’s instructions carefully.

Pet owners today are fortunate to have a wide variety of safe, effective and easy-to-administer products to protect their pets from parasites. By knowing which parasites put your pets—and your family—at risk, and ensuring that the products you give are providing complete protection, you can keep your household safe and healthy.


Ferreting Out Heartworm Prevention

Not just dogs and cats
Ferrets are popular pocket pets that need to be seen by a veterinarian regularly, just like dogs and cats. And like dogs and cats, ferrets can become infected with heartworms. It only takes one mosquito bite for a ferret to contract this dangerous — and sometimes fatal — disease.

The signs of disease
The signs of heartworm disease in ferrets are similar to those in dogs, but they develop more rapidly because the ferret’s heart is quite small. While dogs may not show symptoms until they have many worms infecting their hearts, lungs and blood vessels, just one worm can cause serious respiratory distress in a ferret. Symptoms of this distress include

  • Lethargy (i.e., fatigue, tiredness)
  • Open-mouth and/or rapid breathing
  • Pale blue or muddy gum color
  • Coughing

Prevent so you don’t have to treat
While heartworm disease in ferrets can be treated, the treatment regime is particularly hard on them and oft en unsuccessful. Preventing heartworm is less expensive and much safer than treating it — just as it is for other pets. A veterinarian must prescribe heartworm medication for ferrets. As an added bonus, some preventives also work against other pests that can aff ect ferrets, such as fl eas and intestinal parasites.

Ferrets are extremely susceptible to heartworm disease and are at risk for the disease even if they are indoor pets. The American Heartworm Society recommends year-round prevention for ferrets as well as regular checkups with a veterinarian to ensure they stay healthy and heartworm-free.

Special thanks to Jaclyn Bruce, DVM, Marathon Veterinary Hospital, Marathon, Florida, for her help in preparing this fact sheet.

Don't Try to Predict - Protect

Mosquitoes Thrive in Drought
Weather is always changing and hard to predict. One year, rains are torrential and the next there’s a drought. Many people know that mosquitoes thrive in wet years and breed in wet places. But did you also know that a lack of rainwater doesn’t stop the pesky mosquito from thriving and reproducing in the U.S.? These tiny insects are highly adaptable creatures and easily find other places to breed.

And that means, despite a drought or deluge, your pets are always at risk of getting heartworm disease.

Mosquitoes Are Persistent
When drought conditions exist, many people assume mosquitoes and the diseases they carry are also gone. But despite dry conditions or lack of rainfall, there are plenty of breeding grounds, wherever you live.

While some mosquitoes breed and hatch in response to rainfall, others prefer old tin cans, tires, or they like to lay eggs in birdbaths. In urban areas, many breeding havens are man-made. When it’s very dry, say experts, these pests will search out watered lawns, garden features and underground storm systems to lay their eggs.

Mosquitoes can also carry disease, despite a drought. In humans, West Nile virus doesn’t disappear during droughts. And heartworm, which is transmitted through mosquito bites to pets, is also ever-present.

Heartworm disease is devastating. It can lead to severe lung disease, heart failure, organ damage and death. Both cats and dogs can develop heartworm from the bite of one infected mosquito. That’s why the American Heartworm Society recommends that you Think 12: (1) get your pet tested every 12 months for heartworm and (2) give your pet a heartworm preventive 12 months of the year.


Battling Boredom: Tips for Surviving Cage Rest

Exercise is a serious “no-no” when your dog is undergoing treatment for heartworm infection, so keeping your dog quiet and calm is essential. The following tips can help you navigate this challenging but crucial time period.

What does the treatment for heartworm infection involve?
After your dog has been diagnosed with heartworm infection, he will likely be given a series of different medications. One of these medications is an adulticide that kills the adult heartworms in your dog’s bloodstream. Your veterinarians will administer several injections of this medication over a period of a month. From the first injection until six to eight weeks following the last injection, it will be absolutely essential to keep your dog quiet. That means strictly restricting all exercise and activity that would elevate your dog’s heart rate or increase his blood pressure.

Why does my dog need to be kept quiet during heartworm treatment?
Killing the heartworms that live in the dog’s bloodstream is essential to restoring your dog’s health, but at the same time, the death of the worms—which can grow to be a foot long or longer—poses risks. When heartworms die, pieces of the decomposing worm bodies can block blood vessels in the lungs, causing a potentially fatal pulmonary embolism (blood clot). If the dog’s heart rate is increased by exercise or excitement, the worm pieces can be forced into the tiny blood vessels of the lungs, increasing the chances of complications.

How much do I need to restrict my dog’s exercise— and how do I keep him happy?
Keep your dog indoors and/or in a kennel most of the time. When he needs to go outside to relieve himself, keep his leash on, so that a sudden encounter with a squirrel or other distraction doesn’t send him running.

Here are several other tips to consider:

  • Give him companionship. Social interaction is key to your dog’s behavioral health. Replace activity with affection by keeping him close to you while you watch TV or read. Avoid visitors of both the two-legged and four-legged variety. You may also want to keep your dog away from windows if he’s prone to barking when he sees passersby.
  • Make mealtime last. There’s no need for quick meals, so try feeding toys like Kongs or puzzle feeders that require your dog to quietly play for hours in order to extract food or treats.
  • Let him chew. Dogs that are bored can be destructive to themselves or their environment. Longlasting, safe chew toys can channel this behavior and help keep your confined dog happy.
  • Train the brain. New tricks and games that keep your dog’s brain busy and body rested are perfect for eliminating boredom. Try a game of stationary catch or use a clicker to train him to follow quiet commands while he’s in his crate.

Keeping your treated dog calm and quiet is one of the most important responsibilities a pet owner has during heartworm treatment. Talk to your veterinarian about when increased activity can be reintroduced and take a gradual approach to resuming exercise and activity.

A Walk on the Wild Side

A heartworm-infected animal in the vicinity of an unprotected pet poses an immediate threat. Mosquitoes are like the middleman in a business transaction: they ensure that the “product” — in this case, heartworm infection — gets from Point A to Point B. The trouble is that even if the number of infected dogs and cats is low in a given area, many wild animals living in and around cities, towns and farms can be deadly carriers of heartworm infection.

Mosquito as middleman
It’s not unusual to see foxes and coyotes in backyards across the country. For example, biologists caught and tagged nearly 200 coyotes living in city parks and among apartment buildings and industrial parks in the Chicago area over a six-year period. Although our pets don’t usually come in contact with these critters, the mosquitoes that bite both wild and domestic species expose pets to the infection the critters carry.

Why worry?
Heartworm-positive wildlife should give pet owners cause for concern.

  • These animals are free roaming, so they can spread heartworm disease across wide geographical areas.
  • Because wild animals are not given heartworm preventives, they serve as a constant source of infection.
  • Even if our pets stay indoors, mosquitoes infected by a fox, wolf or coyote in the vicinity can bite them.

Prevention stops heartworm transmission
Since we can’t escape the potential for heartworm disease, the best thing we can do is protect our pets against it. Once a dog gets the disease, treatment is expensive, takes a long time and cannot always repair damage that’s been done to the heart. And because there’s no approved treatment for cats, the best your veterinarian can do for an infected feline is treat the symptoms.

Prevention is the best option. Keeping dogs and cats on year-round heartworm prevention is the best medicine. So think 12 — protect your pets every month, all year long.


5 Facts About Heartworm Disease

The American Heartworm Society (AHS) recommends annual heartworm testing and year-round heartworm prevention. Here are five reasons why:

  1. More than a million pets in the U.S. have heartworm disease. A look at the AHS heartworm incidence map* reveals that in most veterinary clinics in the U.S., a minimum of 1-5 heartworm cases per clinic were diagnosed in 2013, while numerous regions reported 100 cases per clinic or more. These reports do not reflect the status of the millions of dogs and cats that aren’t regularly seen by a veterinarian or tested for heartworm.
  2. Heartworm disease has been diagnosed in all 50 states. Heartworms are spread by mosquitoes. While heartworm disease tends to be associated with regions that have warm, humid weather and high counts of pesky bloodsuckers, heartworm infection is widespread in most states of the country, including states like California and Arizona where the disease was once considered rare, thanks to dog mobility and the variety of mosquitoes that carry heartworm.
  3. Both dogs and cats get heartworm disease. In dogs, adult heartworms that develop from heartworm larvae deposited by mosquitoes cause disease. Cats can also harbor adult heartworms, but it is more common in cats for heartworms to die before reaching maturity. However, even immature worms can cause respiratory disease in cats.
  4. Heartworm disease can be fatal. Heartworm disease affects the heart, lungs and pulmonary blood vessels of pets and can be fatal to both dogs and cats. Annual testing and monitoring is important, because infected dogs can be successfully treated, and the earlier the better. There are no approved treatments for cats, but supportive care can help manage complications.
  5. Prevention is safe, effective and cost-effective. The American Heartworm Society recommends year-round prevention for dogs and cats in the U.S., even in regions that experience cold winters. Heartworm preventives work retroactively, so an animal that acquires an infection one month must be given heartworm preventives in the months that follow to be protected. And with unpredictable weather patterns and the ability of hardy mosquitoes to survive in protected areas—as well as indoors—it’s difficult to predict when heartworms aren’t in season.

Fortunately, heartworm prevention is highly effective when given faithfully, and the year-round cost of preventing the disease in dogs is a small fraction of the cost of heartworm treatment.



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RT @VipPetCare: It is a common myth that the cold, winter months mean your pets are out of harm’s way from heartworm disease, fleas, and ti…

by Heartworm Society