Heartworm: It’s a word we dread hearing, because we know that a dog diagnosed with it has a long, expensive and potentially risky road to recovery ahead.

Last year, the Brown County Humane Society treated 10 dogs for heartworm disease at a cost of more than $1,000. Left untreated, some of those dogs may have died from heartworm disease.

Heartworm disease is caused by a worm spread by the bite of a mosquito. Although it can be found in other mammals, it’s seen most often in dogs.

Initially, there may be no symptoms. In fact, once a dog is infected, it takes about seven months for the larvae to mature. Then, they lodge in the heart, lungs and surrounding blood vessels where they can grow to a foot long and reproduce.

As it progresses, most dogs will develop a cough, become winded with exercise and may have a decreased appetite and weight loss. Dogs with large numbers of heartworms can develop sudden blockage of blood flow within the heart, leading to a life-threatening cardiovascular collapse.

The good news is, heartworm disease is easily preventable.

Heartworm preventatives can be oral, topical or injectable and should be given year-round, even if your dog spends most of the time indoors. The American Heartworm Society recommends giving it all year, for life.

Prevention will generally cost less than $100 per year and may also help prevent other internal parasites.

The preventative may seem like a lot of money “just in case,” and most dogs with mild infections can survive the actual treatment of heartworm if they get it.

However, treatment is expensive, much more so than prevention. It’s also very time-consuming, requiring multiple trips to the vet, blood work, hospitalization and a series of injections.

Much worse than any of that, though, is treatment can be painful and dangerous for your pet. It requires careful monitoring, and your dog would need to have severely limited activity for six weeks or more.

If your dog is at least 6 months old, be sure to have your veterinarian test for heartworms before starting prevention. Preventatives do not kill adult heartworms, and giving a heartworm preventative to a dog with an adult heartworm infection may be harmful or deadly.

Talk to your vet about the best preventative for your pet.

All dogs at the Brown County Humane Society are tested for heartworms (and treated, if necessary) before adoption.