Heartworm disease (HWD) is a serious and potentially fatal disease in dogs and cats that is spread by over 30 species of mosquitoes. Adult heartworms live in the heart and lung blood vessels of infected animals; one pet can have up to 300 worms! Heartworms live for up to 5-7 years and produce millions of offspring that live in the bloodstream until they develop.

Heartworm disease occurs all over the world, but has been increasing in prevalence in the United States, and spreading further and further across the country. New England has been seeing a significant increase in heartworm disease in the past 3-5 years. According to the Companion Animal Parasite Council, there were 674 reported cases in New Hampshire alone in 2018.

Signs

The signs of HWD depend on a number of variables, but are typically due to heartworms clogging the heart and major blood vessels. Signs can include:

  • A soft, dry cough.
  • Shortness of breath, exercise intolerance.
  • Weakness, listlessness, loss of stamina, collapse.
  • RARELY – swelling of the legs and belly, weight loss, and some animals may die suddenly during exercise or excitement.

Diagnosis

Diagnosis of HWD is done by a blood test that can be run in the veterinary hospital. Following diagnosis, further testing is recommended (such as bloodwork and x-rays) to determine if the dog can tolerate the appropriate treatment.

Treatment

In dogs, treatment of HWD is complex, expensive, and can be painful – it involves antibiotics (Doxycycline), an injectable arsenic-based compound to kill adult worms, and steroids to help decrease the inflammatory response when the worms begin to die. Strict rest for several months is incredibly important, as exercise and excitement can lead to dangerous and sometimes life-threatening clots. As long as the disease is not significantly advanced, this disease is treatable. However, in more advanced cases, prognosis can be poor due to substantial damage to the heart, lungs, blood vessels, kidneys and liver. Unfortunately, there is no current treatment for cats.

Prevention

Prevention is so important when it comes to heartworm disease, for both dogs and cats. Preventing the disease prevents damage to the heart and lungs, and avoids a painful and expensive treatment process, as well as strict activity restriction. By preventing this disease, you and your pet can enjoy a life of play and adventure without restriction!

Here are a couple of excellent options for preventing heartworm disease that we recommend here at Hampton Veterinary Hospital:

  1. Interceptor PLUS for dogs – a chewable tablet given monthly, year-round.
  2. Proheart Injection for dogs – an injection given here at Hampton Vet, and lasts 6 months.
  3. Revolution PLUS for cats – a monthly topical, applied year-round.

To learn more about heartworm disease, please visit The American Heartworm Society website.

Always remember, we are here to help! If you have any questions or concerns about your pet and heartworm disease, please don’t hesitate to contact us!