How To Prevent Heartworms

Heartworm prevention is crucial for maintaining your pet’s health and preventing sickness, along with routine immunizations and wellness checks. Keep your four-legged buddy on heartworm prevention year-round because mosquitoes don’t hibernate during the winter and heartworm illness has been identified in every U.S. state.


The heartworm life cycle

Any mammal can be infected with heartworms, although these parasites prefer canine hosts. When a mosquito bites an infected animal, they ingest microfilariae, or heartworm larvae (L1), from the blood vessels. The mosquito’s gastric juices stimulate the larvae to molt to the L2 stage, and they then migrate to the mosquito’s salivary glands and molt to infective L3 larvae. When the mosquito feeds, the L3 larvae swim under the pet’s subcutaneous tissue. Over time, the larvae molt through two stages, traveling toward the pet’s heart until they finally arrive in the main pulmonary artery, where they reach adulthood and reproduce.


How heartworm prevention works

The mosquito develops into several different stages within the pet, but only two of those stages are sensitive to heartworm prevention. Heartworm larvae cannot be killed by preventives once they reach the juvenile or adult stage and must be treated with a severe and expensive medicine that contains arsenic.

By giving your pet a monthly heartworm preventive, whether an oral chewable or topical liquid, you effectively kill off the heartworm larvae before they develop into a more hardy life stage. Since immature larvae can molt into the adult stage in as little as 51 days, monthly prevention that does not allow the life cycle to progress and harm your pet is critical. Injections with a slow-release mechanism that ensures heartworm larvae are killed before they molt can also be administered every 6 or 12 months. While heartworm prevention does not prevent mosquitoes from biting your pet, or heartworm larvae transmission, it ultimately prevents life-threatening heartworm disease. 

In honor of National Heartworm Awareness Month, investigate heartworm preventive options for your pet. Give our team a call to discuss the heartworm preventive that will best keep your four-legged pal safe from disease.