Many dog owners have heard of heartworm disease but may not fully understand how the disease develops. Some owners may even question if an annual test for heartworm disease is necessary. Dr. Sonya Wesselowski, clinical assistant professor of cardiology at the Texas A&M College of Veterinary Medicine & Biomedical Sciences, said testing for heartworm disease and administering regular monthly heartworm medication is crucial.
“All dogs should be tested for heartworm disease every year at their annual wellness visit. “Additionally, patients that have not previously been on heartworm prevention or those that have had a lapse in their heartworm prevention should be tested immediately, then again in six months, and annually thereafter.”
To help dog owners understand why preventing heartworm disease is so important, Wesselowski explained how the disease develops. “Heartworm disease is caused by a long, thin worm known as Dirofilaria immitis,” she said. “Heartworms live within the heart, lungs, and blood vessels and can cause damage in these areas. This damage can lead to lung disease, elevated blood pressure inside the lungs, and even heart failure. In some cases, other organs in the body are affected as well.”
“The first step in the heartworm lifecycle occurs when a mosquito bites an infected dog,” she continued. “The mosquito ingests the microscopic offspring of the adult heartworm known as microfilaria. These microfilaria then mature inside the mosquito over ten to 14 days and become infective larvae that can be deposited onto the skin of another animal when the mosquito bites again. The larvae enter their new host through the bite wound left by the mosquito and develop into adult heartworms in about six months. The adult heartworms can then live for five to seven years in the infected dog.”
Wesselowski also stressed that the treatment of heartworm disease is expensive for pet owners and taxing for affected pets. The heartworms can also cause long-term damage to the heart and lungs that remains even after the heartworm infection is successfully resolved. This means that when it comes to heartworm disease, prevention is key.
“Administration of regular monthly heartworm preventatives is crucial to prevent heartworm disease and to avoid the stress, expense, and potential complications that can be associated with heartworm treatment in our beloved family pets,” Wesselowski concluded.