April is National Heartworm Awareness Month, which is a good time to brush up on your facts. Heartworm affects an estimated one million dogs each year and can be costly to cure. Knowing how to prevent your dog from getting heartworm is important for your dog’s health.
Getting the heartworm
The only way for a dog to get heartworm is from a bite of an infected mosquito. Dogs cannot transfer heartworm to each other or to humans. There have been some rare cases of humans getting heartworm from the bite of an infected mosquito, but the parasite is able to thrive more in dogs and cats and isn’t complete its full life cycle in humans. Heartworm in dogs has been reported in all 50 states. Once a dog has been bitten, it takes around seven months for the parasite to develop from the larvae into adulthood. Heartworms embed themselves into the heart, lungs, and surrounding blood vessels to begin reproducing. Heartworms can live for as long as five to seven years and can grow to be 12 inches in length. An infected dog can have around 250 heartworms.
Treating an infected dog
When a dog is first infected with heartworm, he won’t have any symptoms which make it harder to diagnose. Over time, he will develop a cough and may not exercise as long; he will be short of breath easily. Heartworms can prevent blood flow to the brain, causing your dog to pass out. If not treated, your dog will die. Your veterinarian will need to run tests, including x-rays and blood work, to determine how serious the infection is. Your dog will be given injections containing the drug Immiticide, which is an injectable, arsenic-based product. Your dog will receive two to three injections which will kill the heartworms. After receiving treatment, your dog will need to rest for several months. As the worms begin to die, they break up into pieces which can cause blockage in the pulmonary vessels and can cause death. Studies have shown that dogs who exercise after treatment are more likely to die. This stems from the popular belief that the treatment drug causes dogs to die. One common misconception about heartworm treatment is that once a dog has been treated, he can’t get heartworm again. This is false; your dog can still get heartworm again after being treated. This is why prevention is so important.
Some people might believe that preventing heartworm is too expensive, but keep this in mind: treating heartworm and the damage it does to your dog’s health is much more costly. You can purchase pills or topical that is applied to your dog’s skin. Your veterinarian can also administer injections every six months. Do not skip a month; some people believe that it’s useless to do prevention during the winter months when mosquitoes aren’t around. Skipping a month or more may cause your dog to be less protected. You wouldn’t skip a dose or two of your own medication, so why do it to your dog? Many of the heartworm preventative medications available today contain other intestinal parasite controls, just another reason to keep up with your dog’s medication.