What is Heartworm?
Heartworm is a parasite which lives in the blood of a dog’s heart and adjacent blood vessels. The adult heartworm produce offspring, called microfililariae, which circulate in the infected dogs blood.
When a mosquito “bites” an infected dog, it sucks out blood containing the microfilariae. After about two weeks in the mosquito, the microfilariae become infective larvae. This step is necessary for the transmission of heartworm. When the mosquito bites another dog, the infective larvae are transmitted.
The infective larvae migrate through the tissues of the dog’s body and reach the heart in about 2 to 3 months. In the heart the larvae develop into adult heartworms. It takes about six months from the time the dog is bitten by an infected mosquito until adult heartworms produce microfilariae.
In the early stages of disease most dogs show few symptoms. As the disease progresses dogs may show difficulty breathing, coughing, listlessness, weight loss and rough hair coat. If not detected and controlled with proper treatment, heartworm can lead to congestive heart failure and death.
Prevention and Testing
Heartworm preventative medications (Heartguard, Sentinel, Interceptor, Revolution, Advantage Multi) prevent the heartworm larvae from developing into adult heartworms. These medications are given monthly from June until November. It is necessary to have your dog heartworm tested prior to using a preventative.A small amount of blood is all that’s necessary for the test which is very accurate in detecting the presence of heartworm. Dogs with a negative test can start on preventative. Dogs with a positive test require special treatment to kill the adult heartworm and microfilariae.
To set up an appointment for your dogs heartworm test and preventative give us a call at 519-542-2553.