Heartworm disease is a serious and potentially fatal condition caused by parasitic worms living in the arteries of the lungs and occasionally in the right side of the heart of dogs, cats and other species of mammals like ferrets. Heartworms are classified as nematodes (roundworms) and are filarids, one of many species of roundworms. Dogs and cats of any age or breed are susceptible to infection.
So, how could my pet get heartworms? How would I know if they have them? What happens if they do? How do I keep my pet from getting them?
Well, lets try and hone this down a little to the skinny of the matter.
How do pets get Heartworms?
Dogs or other animals harboring adult worms are the recognized reservoir of heartworm infection. The disease is spread by mosquitoes that become infected with microfilariae while taking a blood meal from an infected dog.
(As we all know mosquitoes and Georgia are a hand in hand statement, especially this year. )
Within the mosquito, the microfilariae mature into the infective larval stage. When the mosquito then bites another dog, cat, or susceptible animal, the larvae are deposited on the skin and actively migrate into the new host. For about 2 months the larvae migrate through the connective tissue, under the skin, then pass into the animal’s venous blood stream and are quickly transported to the arteries of the lung. It takes a total of approximately six months for the infective larvae to mature into adult worms that begin producing offspring, microfilariae. Adult heartworms can live for five to seven years in the dog.
The larvae progress in their development to an adult form of the worm, and live in the pulmonary vessels (leading and in the heart) , where they continue the life cycle and cause extensive injury. The period of time when heartworms are reproductively capable is referred to as patency.
In cats, it takes seven to eight months before adult worms potentially reach potency in the pulmonary vessels, and this is referred to as transient potency, as reproductive capability in the cat is usually very short (months) compared to that of dogs years).
In the cat, the larvae molt as well, While dogs may suffer from severe heart and lung damage from heartworm infection, cats typically exhibit minimal changes in the heart. The cat’s primary response to the presence of heartworms occurs in the lungs, but heartworms can also lead to sudden death in many cases. Heartworms do not need to develop into adults to cause significant pulmonary damage in cats, and consequences can still be very serious when cats are infected by mosquitoes carrying heartworm larvae. Newly arriving worms and the subsequent death of most of these same worms can result in acute pulmonary inflammation response and lung injury. This initial phase is often misdiagnosed as asthma or allergic bronchitis but in actuality is part of a syndrome now known as Heartworm Associated Respiratory Disease.
The thing is is in a lot of cases our pets don’t show symptoms of heartworms until it has become a serious issue. Which is why with a minimum of once a year, again especially living in Georgia, you should test your pet for Heartworms. Even more important is to have and/or get your pet on preventative. The thing about being on preventative though, is you ALWAYS want to test for hearworms before administering preventative. Why?
Dogs & Cats older than six to seven months of age should be tested for heartworms before starting heartworm prevention. They may appear healthy on the outside, but on the inside, heartworms may be living and thriving. Although they may shorten the lifespan of the worms, heartworm preventives do not kill adult heartworms. If a heartworm-positive dog is not tested before starting a preventive, the dog will remain infected with adult heartworms until it gets sick enough to show symptoms. Also, giving a heartworm preventive to a dog that has an adult heartworm infection may be harmful or deadly. If microfilariae are in the bloodstream, the preventive may cause the microfilariae to suddenly die, triggering a shock-like reaction and possibly death in some animals.
There are a variety of options for preventing heartworm infection, including daily and monthly tablets and chewables, monthly topicals and a six-month injectable product. These products are extremely effective and when administered properly on a timely schedule, heartworm infection can be prevented.
We recommend year-round prevention, even though it is Georgia and there are ALWAYS mosquitos, it is important no matter where you live to do year round preventative. One reason for this is compliance – to make sure the medicine has been given properly. In addition, most monthly heartworm preventives have activity against intestinal parasites. Many of these same intestinal parasites that infect dogs can also infect people, with estimated infections occurring in three to six million people every year. So this added benefit of monthly deworming makes A LOT of sense.
As far as preventative our facility prefers the use of Revolution. Just one application a month provides protection against heartworms, fleas and other parasites.
Heartworms can be dangerous to our pets, and the ONLY way to ensure your pet doesn’t suffer from them is to test each and every year and maintain usage of preventative each month on the same day preferably.