If veterinarians are not dispensing heartworm preventives to their clients, there’s a good chance their clients are not protecting their pets

Heartworm prevention typically costs pet owners as little as $10 each month. But, for those who neglect to follow through, the toll on their pets’ health, as well as the expense of treatment, can be tremendous.

A large number of dogs, and an even greater percentage of cats, are not on heartworm prevention but should be, according to experts. In part, this is due to client misperceptions: Many pet owners do not realize that the disease is easily transferred by mosquitoes, while others believe that heartworm is easily “cured” by giving their pet a pill. At the same time, some vets fail to convey a sense of urgency about heartworm prevention to their clients. Before sales reps can sell their customers on the importance of heartworm prevention, they should help vets understand their clients’ complacency.

What is heartworm
Heartworm infection is caused by worms (Dirofilaria immitis), which sometimes mature into 14-inch-long adults, according to the American Heartworm Society. Adult worms live in the right side of the heart and the arteries of the lungs, causing arterial damage and eventually heart failure. In extreme cases, the disease leads to organ damage as well, particularly liver and kidney.

The infection is spread from one animal to the next by mosquitoes, which become infected with microfilariae while taking a blood meal from another animal. The microfilariae mature to the infective larvae stage in the mosquito for the next 10 to 14 days. When the mosquito bites another animal, the infective larvae enter through the bite wound.

A number of animals, including dogs, cats, ferrets, coyotes, wolves and sea lions, may be infected with heartworm. However, the two largest reservoirs are untreated dogs and coyotes.

Generally, cats appear to be less susceptible to the disease, with fewer worms surviving into adulthood. When an infected mosquito bites a cat, it takes about eight months for the infective larvae to mature into adult worms, which may live for two or three years in the cat. In dogs, on the other hand, infective larvae take a little over six years to mature into adult worms, which live between five and seven years. While heartworm is more prevalent in regions more heavily infested with mosquitoes, the disease has been identified throughout the nation with the exception of Alaska.

Testing and treating
For both cats and dogs, clinical signs of heartworm disease often are not apparent in the early stages, since heartworms tend to accumulate gradually over a period of months or years, and after repeated mosquito bites, according to the American Heartworm Society. As the disease progresses, cats exhibit non-specific clinical signs, which mirror other feline diseases, including vomiting, gagging, difficult or rapid breathing, lethargy and weight loss. Untreated cases may result in death. Dogs exhibit such signs as mild, persistent coughing, reluctance to move or exercise, exhaustion following moderate exercise, reduced appetite and weight loss. Untreated cases lead to heart or lung failure, and fluid buildup in the abdomen.

Despite the danger, data indicate that about 60 percent of client-owned dogs have not been placed on heartworm prevention. Pet owners are often unaware that the disease is so easily transferred via mosquito bites. Sometimes they think they can save money by foregoing the preventive medicine, and then simply give their dog a pill if it is diagnosed with heartworm. The reality is, it costs less than $10 a month for preventive medicine, whereas treatment can run as much as $1,000.

Diagnosing canine heartworm infection involves several steps:
• Recording an accurate patient history.
• Recognizing clinical symptoms.
• Administering several diagnostic procedures, including serological testing (for antigens and antibodies), microfilarial detection and differentiation, X-ray and angiography.

Treatment, which involves administering an organic arsenical compound, can be expensive. As the heartworms die, inflammation may occur in the dog’s lungs, so veterinarians often require that they be hospitalized for a couple of nights and restrained in a crate for as long as a month or more.

Feline heartworm infection is more difficult to diagnose, and negative results do not always rule out an infection. In fact, an antigen test detects only adult female or dying male worms. Immature or male-only worm infections are rarely detected. The diagnostic plan for heartworm in cats may involve:
• Physical exam.
• X-ray.
• Echocardiograph.
• Angiocardiograph.
• CBC.
• Serological testing (for antigens and antibodies).
• Microfilaria testing.

There is no approved treatment for feline heartworm infection. In some cases, cats are monitored with chest X-rays. Cats with radiographic or clinical evidence of lung disease may be given small, decreasing doses of prednisone. In severe cases, the animals require intravenous fluids, oxygen therapy, cage confinement, bronchodilators, cardiovascular drugs or antibiotics.

Prevention
For your customers and their patients, heartworm prevention is not only a practical solution, but a much gentler approach than permitting the disease to progress to the point where treatment is needed. But, unless veterinarians communicate the importance of a good preventive program, clients likely will not take this route.

Depending on the product, heartworm treatment should begin around the age of six weeks. Heartworm preventive products should be administered to pets on the same day of each month. This dose kills heartworm larvae that are migrating in tissues under the skin. However, when the dog or cat ventures outdoors again, it may be bitten by a mosquito and reinfected with new larvae. If the pet does not receive the next dose of preventive medication a month after the last dose, the new larvae have an opportunity to mature into adult worms that cause heartworm disease.

How to sell
When sales reps pay their veterinarian customers a visit, they should not assume all practices are equally diligent about dispensing heartworm preventives. Often, veterinarians have great intentions of ensuring their patients are on a heartworm preventive, yet they do not realize how many clients leave their office without a prescription.

Reps should begin the sales process by discussing the clinic’s policy for addressing heartworm prevention. Some good probing questions for vets include the following:
• “Doctor, what is your recommendation to your clients regarding heartworm prevention?”
• “Do you know whether your clients are leaving the clinic with the products you recommend?”
• Would you mind if we look at some records and verify this?”

As many as 1 million dogs are infected with heartworm in this country, and thousands become infected each year, according to some experts. A simple discussion can lead to healthier dogs and cats, more satisfied clients and a stronger bond of trust between doctor and client.

Editor’s note: Vet-Advantage would like to acknowledge the contribution of MERIAL Ltd. (Duluth, Ga.).

Sidebar:

When Results Count
On-the-spot test results help veterinarians keep their heartworm patients on track

When it comes to their pets’ health, owners are looking for information – and lots of it. And, the faster veterinarians can provide that information, the happier their clients are. Distributor reps may not be magicians, but in some cases, they can help their veterinarian customers provide more data, efficiently and accurately.

Heartworm testing for dogs and cats is not new, yet some veterinarians may need a bit of encouragement to come on board. Available as a blood or serum test, the heartworm test reportedly yields results in less than 10 minutes, enabling veterinarians to inform their clients if their pets have heartworm (or in some cases, another vector-borne disease, such as Lyme disease or ehrlichiosis) and place the animal on a preventive before they leave the office. It’s better for patients and more convenient for clients, who will appreciate the quality of care their pets are receiving.

Benefits of heartworm testing include:
• Immediate results, which facilitate immediate consultation with clients.
• Clients can leave with a heartworm preventive.
• Testing ensures the warranty on the preventive remains valid.
• The veterinarian knows his treatment plan is on track from the start.

What your customers don’t know
Although heartworm testing has been available to veterinarians for about 20 years, the technology is only recently catching on for cats. “Cats have handled heartworm better in the early stages, so testing is lagging behind here,” says Michael Sullivan, director of marketing, IDEXX Laboratories Inc. (Westbrook, Me.). “But the reality is that different problems affect cats [than dogs], so they need to be screened and put on prevention as well.”

Indeed, cats are at risk for feline asthma (associated with juvenile-stage heartworms) and acute death (associated with adult-stage heartworms). “So, cats need to be screened and put on preventive [medication] as well,” says Sullivan. “The issue for cats is real.” But, people can be slow to change their ways of thinking, he adds.

Even when veterinarians are aware of the importance of screening both dogs and cats for heartworm, in some cases, they prefer to send the tests to a reference lab, notes Sullivan. “It’s a workflow issue,” he points out. “Some practices don’t have enough in-house staff to run the tests.”

However, most practices are used to running some level of testing in-house, he continues, and sales reps should initiate a discussion with their veterinarian customers to gauge their needs. “Reps should get the veterinarians to talk about their wellness programs,” says Sullivan. “Some practices have moved to twice-a-year wellness checks, one of which [includes] heartworm screening.”

Distributor reps should begin a discussion by asking some questions, including the following:
• “Doctor, can I ask you about your heartworm prevention protocols?”
• Have you considered testing for related diseases, such as Lyme disease or ehrlichiosis?”

“Heartworm testing can be the link for further healthy animal discussions,” says Sullivan. Indeed, the rep can springboard from heartworm preventives to flea and tick care, weight issues and nutrition. After all, the more information reps can offer their veterinarian customers, the better the care veterinarians can offer their patients.