Heartworm disease is caused by a parasitic worm that is transmitted through the bite of an infected mosquito and can infect both dogs and cats. Early in the disease, dogs can be asymptomatic. Signs are often progressive over weeks to months, and if left untreated the infection can be fatal. Heartworm infection can affect many different organs of the dog including the heart, lungs, kidneys, and liver, so symptoms may be varied. Most commonly though, signs of heart or lung disease are present. A veterinarian may suspect that a dog has been infected if an active animal tires easily or shows shortness of breath or coughing.

Heartworms have been found in dogs in all 50 states so all dogs are at risk anywhere infected mosquitos inhabit, even those animals that primarily live indoors. It’s now more important than ever to keep your pet protected as heartworm prevalence is expanding greatly across the U.S. The increase in prevalence can be attributed to several factors including warmer and humid weather patterns that create ideal breeding conditions for mosquitoes; transportation of companion animals from one are of the country to another; and pet owners who don’t administer parasite preventatives 12 months of the year. Year-round preventative care is the best way to keep your pets protected.

Talk to your local vet about the best preventative options for your pet and be sure to test your pet annually for heartworms as they can show no symptoms until the infection is well-established. Pet Disease Alert’s 30-Day forecast maps are a great way to visualize high-risk areas for heartworm disease, but they can also serve as an early-warning system for areas of emerging risk.