Presenting Heartworm Awareness Month

mt. carmel animal hospital heartworm awareness month

Since it’s Heartworm Awareness Month, discuss heartworm preventive medications with our vets to determine the best option for your dog.

Heartworm disease is likely fatal to dogs without treatment and is caused by foot-long worms that linger in their heart, lungs, and blood vessels. When left untreated, canines can have hundreds of worms at a time, causing permanent damage to their organs. In honor of Heartworm Awareness Month, Mount Carmel Animal Hospital wants to ensure you are equipped with what you need to prevent this possible harmful disease in your dog.

What is Heartworm Disease?

Heartworm disease is caused by Dirofilarial immitis, a type of roundworm. This parasite lives in the lungs, heart, and blood vessels of affected pets. If left untreated, it may lead to lung disease, heart failure, and general organ damage. A single adult heartworm can grow up to 12 inches long and survive for up to 7 years in your dog.


Mosquitos are the most prevalent carrier of heartworm. A mosquito picks up heartworm larvae known as microfilaria when it feeds off of an infected cat’s or dog’s bloodstream and then transmits them into the next animal it bites. Even though dogs are ideal for receiving heartworms, cats can also become hosts. Heartworm larvae take about six months to evolve into adult worms that settle into the animal’s organs.

Signs of Heartworm Disease

The bite of an infected mosquito leads to heartworm disease, making dogs prone to it any time mosquitoes are around. In the early stages of heartworm disease, canines might exhibit little to no symptoms. As the infection develops and disease progresses, symptoms will show up:

  • Mild persistent cough
  • Fatigue following even moderate exercise or activity
  • Decreased appetite
  • Weight loss
  • Labored breathing
  • Pale gums
  • Swollen abdomen


Once diagnosis has been confirmed with the proper testing, treatment can be administered to dogs to kill the heartworms. The treatment process recommended by the American Heartworm Society involves several medications prior to three injections given at specific time periods. Treatment takes three months. The dog’s activity needs to be severely restricted during treatment to prevent pieces of the dead worms from being forced into the blood vessels of the lungs and causes a fatal pulmonary embolism. A month after your dog has finished treatment, they will be retested for the larvae. If positive, your dog will need another injection and then retest again one month after. If negative, your dog will need one more blood test in 6 months to ensure the infection has been cleared.

Cats with heartworms are more difficult to diagnose and treat than dogs. Cats require a blood draw to search for antibodies and antigens in response to a heartworm infection. At this time, there is no approved treatment approval for infection in cats, so prevention is key. Cats should be started on a heartworm preventative as soon as possible.


Fortunately, heartworm disease is preventable! Heartworm prevention medicine comes in different forms, including flavored chewable pills, injectable medications, and topicals. Many heartworm preventatives, like the Sentinel Spectrum that we carry at Mount Carmel Animal Hospital, also protect against intestinal parasites. This includes roundworms, hookworms, whipworms, and tapeworms. Heartworm medication is only available by prescription via your vet. Since it’s Heartworm Awareness Month, discuss heartworm preventive medications with our vets to determine the best option for your dog.


Mount Carmel Animal Hospital has been serving the Northern Baltimore/Southern York community for over 30 years and is proud to be an independently operated, small animal practice committed to excellence in veterinary medicine and client service. From grooming to wellness services, along with Canine Life Skills Training Courses, and surgical procedures, we have the expertise that will best serve the needs of you and your pet. Contact us at 410-343-0200 and follow us on Facebook

This entry was posted on Friday, April 12th, 2024 at 9:16 am. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.