I thought that instead of showing gory pictures of heartworms spilling out of a dog’s heart, I would educate about what heartworms are and why we care so much about preventing them.
Heartworms start their lifecycle in the heart. They fall in love, and soon little heartworms are running all around the bloodstream. These are called microfilaria, and they are so small that they can go to the tiny vessels near the skin. It is here that mosquitoes suck them up when they take a bloodmeal. The baby heartworms mature into teenagers in the mosquito, then they are injected into another dog’s skin when the mosquito bites. They hang around for a month (you know teenagers), and then slowly meander into the bloodstream towards the heart. In the heart they become adults and live inside the chambers of the heart and vessels of the lungs, causing problems and waiting to fall in love to start the whole process again.
Problems with Heartworms
Heartworms cause problems a couple different ways.
They can interfere with the heart’s ability to pump blood throughout the body . This can create a backflow of blood, which results in heart failure (see my previous post about this). They can even cause a clot in the lungs and can cause sudden death or severe difficulty breathing.
Because they are foreign invaders in the system, the immune system reacts to their presence. The blood vessels in the lungs can become thickened and function less efficiently. Immune complexes in the kidneys can form and cause kidney failure.
Ounce of Prevention
Heartworm prevention is relatively easy. Prevention works by killing off any baby heartworms as they enter the skin from the mosquito.
Monthly preparations such as Heartguard, Interceptor, and Iverheart (or other generic formulas of Heartguard) are very inexpensive.
Prevention to control fleas and prevent heartworms includes Trifexis, Sentinel, Advantage Multi, and Revolution. These are also given on a monthly basis.
A six month injectible prevention called Proheart is also available. No forgetting to give pills for this one, and its only given twice a year.
All of these are relatively inexpensive -$5-20 a month – depending on generics vs combination products.
Pound of Cure
Heartworm treatment is expensive and potentially dangerous. The heartworms can cuase problems as they die, so we have to keep these patients strickely confined for anywhere from four to ten weeks. If they are not confined or if the prior damage was too much, the treatment itself can kill the patient. Even then, the injections are painful, and the average cost of treatment is around $400-500 here in South Atlanta.
Hopefully, with all the mosquitoes was have here in the South and with all of the heartworm postive dogs that live outside, there is no reason why the ounce of prevention shouldn’t win every time.
– Doc Cleland