Heartworm disease is a major threat to dogs and cats. Heartworm is a parasite that can also live in other animals, for example, foxes, coyotes, wolves, ferrets, and sea lions. According to recent findings, over 100,000 domestic dogs contract heartworm disease annually in the U.S. If untreated, the infection can result in heart and lung conditions and even death. The prevalence of heartworm has increased in San Diego County in recent years, and it is recommended that every dog and even cats receive heartworm preventative monthly. 

Understanding Heartworm 

This disease comes from the parasitic worm called Dirofilaria immitis. The thread-like worms can reach up to 14 inches long and the adults live in the pulmonary artery of your animal’s heart. 

Consequently, heartworms create blockages and interrupt blood flow. By doing so, the parasite may inhibit proper oxygenation of the tissues of the body. This could stress major organs such as the kidneys, liver, and of course, the heart itself. 

How Dogs Get Heartworm

Since the disease isn’t contagious, your pet cannot catch heartworms by staying near an infected animal. However, heartworm disease spreads through a mosquito bite from an infected animal to a healthy one. Note that dogs are definitive heartworm hosts–their bodies allow the parasite to mature and reproduce. Without treatment, heartworms live between five and seven years and multiply to the hundreds. On the other hand, cats don’t host heartworms to sexual maturity. Because the parasite doesn’t breed, cats typically host around one to three heartworms However, because of their size, even 1-2 heartworms can be detrimental to an infected cat. 

Symptoms of heartworm disease may go unnoticed during the initial stages. The fact that animals hide their vulnerabilities doesn’t help the situation. However, symptoms begin to show as the infection progresses. Heartworms manifest in different ways depending on the animal. For example, dogs may exhibit the following signs:

• Breathing difficulties

• Low appetite

• Weight loss

• Lethargy

• A swollen belly from fluid accumulation

• Dry cough

Note that heartworm disease could prove fatal if left untreated. If the worms shut off blood flow, immediate surgery might be necessary to remove the parasite. This last stage of heartworm disease is called Caval Syndrome which displays symptoms such as pale gums, dark urine, and labored breathing.

Conversely, infected cats may show nonspecific symptoms that could pass for other diseases. That includes weight loss, vomiting, poor appetite, and decreased activity. Although infected cats rarely exhibit symptoms of heart failure, the animal may experience respiratory difficulties due to lung damage. You may notice coughs, breathing difficulties, and an increased respiratory rate. 

Heartworm Testing and Treatment

Since initial infection can go unnoticed and signs can be non-specific, yearly heartworm testing is essential. You also might want to get your pet tested if they show any of the aforementioned symptoms. Ordinarily, the vet takes your dog’s blood sample to look for heartworm proteins. When the test is positive, the doctor may administer confirmatory checks such as X-rays, additional blood tests, and echocardiograms.

The vet then proceeds to stabilize the symptoms with appropriate therapies to prepare your pet for treatment. Afterward, your vet administers melarsomine dihydrochloride, an FDA-approved treatment that kills adult heartworms. If the case is severe, your pet undergoes surgery to pull out the parasite. You will also have to confine your pet to minimize stress on the lungs and heart and accelerate recovery.

In the case of cats, the vet administers a series of tests to look for the illness. For example, an antibody and antigen test may detect the disease in its early and later stages. Ultrasound imaging could also reveal worms inside the heart and pulmonary vessels.

When it comes to treating cats, veterinarians monitor the condition to see whether it resolves itself. Because cats have no approved heartworm treatment, the vet manages the disease through supportive therapy or surgery for serious cases.

Preventing Heartworm

You can save your pet’s life and avoid hefty treatment costs through preventative measures. The vet can examine your animal for heartworms and similar parasites during routine checkups. If there are no signs of the disease, your veterinarian can administer injectable, oral, or topical preventatives to avoid infection.

Read more:

• These Are Some of the Most Commonly-Performed Pet Surgeries

• What Your Vet Means by “Routine Diagnostics”

• What to Expect During Your Pet’s Annual Exam