Heartworm Testing in Dogs
Published June 18, 2021
Heartworms are parasitic worms that live in the hearts and lungs of dogs and spread through the bite of an infected mosquito. All dogs are at risk, even those that are indoors only. Untreated, heartworm disease can result in severe heart damage and even death. Fortunately, a simple heartworm test and monthly preventative can keep your pet safe and healthy.
To understand the importance of heartworm tests, it is important to first understand the heartworm lifecycle. Heartworms are spread through the bite of an infected mosquito. When a mosquito bites an infected dog or other susceptible animal, it withdraws blood that contains immature heartworms called microfilariae. The infected mosquito spreads the disease to other animals through bites.
It takes about six months from the time of the mosquito bite before the immature heartworms develop into adult heartworms that are capable of reproducing microfilariae and also detectable on a heartworm test. An adult heartworm can live up to seven years in the dog, and a single dog can have up to one hundred adult worms in its heart, lungs and circulatory system. The more worms, the more damage that is caused to the heart and the vessels in the lungs. Eventually, without treatment, the dog will develop heart failure.
During the bite, the mosquito injects the immature parasite into the bloodstream. The immature heartworms use the animal’s bloodstream as a circulatory superhighway to spread out to the lungs and the heart where they mature into adult worms, eventually capable of producing more microfilariae. The cycle of the disease continues when another mosquito bites the newly infected animal and then moves on to infect more animals.