One mosquito bite can cause the parasite to enter a pet’s body and mature into long worms that live in the heart and major vessels surrounding the heart. Heartworm disease can affect both dogs and cats. Untreated, the disease leads to significant and deadly damage to the pet’s heart, lungs, kidneys and liver.

Although heartworm disease is present in all 50 states, Banfield’s Applied Research and Knowledge (BARK) team reports that heartworm disease is most prevalent for dogs in Mississippi, Arkansas, Louisiana, Texas and Alabama. In cats, heartworm is not as common, but according to BARK, the consequences can be very serious since the disease is much more difficult to treat in cats than in dogs.

Symptoms of heartworm disease
While heartworm disease might not cause your pet to exhibit symptoms in the early stages, if left undetected and untreated, it can cause sudden death. In most cases, a pet will show no initial signs of having the disease.

Symptoms of heartworm disease can include the development of a persistent cough, reluctance to exercise, fatigue after light exercise and a decrease in appetite and weight. Cats’ symptoms of heartworm disease can include vomiting, rapid breathing and weight loss. The treatment of adult heartworms in cats is usually not recommended so prevention of the disease is particularly crucial for cats.

Diagnosis and treatment
If your dog is diagnosed with heartworm disease, your Banfield veterinarian will perform lab tests, such as a complete blood count and a urinalysis. He or she will then begin treatment, which typically includes medications to end the lifecycle of the heartworms. During the treatment process—which can vary in length but usually lasts for a few months—your veterinarian will continue to perform routine blood work to monitor the progress of the treatment. He or she will instruct you to limit your dog’s activity. After treatment, heartworm preventives will generally be recommended to prevent re-infection.

Heartworm disease prevention
Heartworm is easily transmittable—in fact, heartworm can be passed through the bite of just one mosquito. Implementing a year-round monthly heartworm preventive, as well as a yearly heartworm test, is crucial for minimizing your pet’s risk of contracting heartworm disease. If you have questions about this or any medical topic, please contact your veterinarian today.