What is Heartworm Disease?
Heartworm disease is a serious and potentially fatal condition caused by parasitic worms which live in the arteries of the lungs and heart of dogs and more rarely cats. The microscopic form of these worms is transmitted by mosquitoes. They are then injected into the pets where they mature into adult worms.
Adult female heartworms inside of a dog release the baby heartworms, called microfilariae into an animal's bloodstream. When mosquitoes feed upon the infected host, they ingest the microfilariae while taking their blood meal. During the next 10 to 14 days, the microfilariae mature to the infective larval stage within the mosquito. After that, the mosquito bites another dog, cat or other susceptible animals, and the infective larvae enter through the bite wound. It then takes a little over six months for the infective larvae to mature into adult worms. In dogs, the worms may live for up to seven years. Microfilariae cannot mature into adult heartworms without first passing through a mosquito.
How is Heartworm Disease detected/prevented?
Heartworm disease is detected by drawing three drops of blood and looking for an antigen to microfilariae. It takes only eight minutes and is done in-house. Once the animal is found to be negative, they are started on a preventative product. This product not only prevents heartworm but also intestinally deworms the dog on a monthly basis. For the pets overall best interest, heartworm products should be given year-round. The product needs to be given at least 30 days past the last mosquito to thoroughly kill any microfilaria which may be inside the pet. There is a different type of heartworm product available- either chewable tablets, topical products or even an injectable which lasts for six months. The intestinal parasite coverage varies with each product but they all do a great job at prevention of heartworm disease.
What happens if a dog tests positive?
Usually, all but the most advanced cases of heartworm disease can be successfully treated in dogs. Adult heartworm in dogs is killed using a drug called an adulticide which is injected into the deep muscle of the back through a series of treatments. Because this is a very serious condition, we need to keep the activity level of the dog to a minimum for a number of months.
When the dog is sent home, exercise should be limited to short leash walks for the duration of the recovery period.
This restriction decreases the risk that a partial or complete blockage of blood flow happens which can result in sudden death.
Many dogs are treated in the United States each year and have a very positive outcome, however, it is a much easier disease to prevent than treat. The best prevention to use is HeartGard which your Pipestone vet professional can speak to you about.