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Heartworm Awareness Month

April is Heartworm Awareness Month  

Heartworm disease is a serious and potentially fatal disease most commonly found in dogs. It is caused by the parasitic roundworm called Dirofilaria immitis. These worms can grow to be very large and live in the heart, lungs, and the associated blood vessels, causing severe heart and lung diseases, heart failure, and damage to other organs.

Dogs are natural hosts for these worms, meaning heartworms that live inside of dogs have to ability to mature into adults and produce offspring.  If left untreated, the number of worms will continue to multiply and lead to irreversible damage. Cats on the other hand are atypical hosts for heartworm, and most worms in cats do not survive to the adult stage.

Heartworm is transmitted through mosquitos. Adult female heartworms living in an infected dog, fox, coyote, or wolf produce tiny baby worms called microfilaria that circulate in the bloodstream. When a mosquito bites and takes blood from an infected animal it picks up these baby worms, which then develop into mature larvae in 10-14 days. Then, when the infected mosquito bites another susceptible animal, the larvae enter the new host’s bloodstream though the mosquito’s bite wound. It takes approximately six months for the larvae to develop into mature adult heartworms that can live for 5-7 years inside a K-9 host.

Areas with low populations of mosquitos can still have a high level of heartworm infections. Many factors come into play when looking at the transmission of the disease. While you and your dog may not travel to areas of greater heartworm risk, other pets in the area do and may bring the disease back with them.  The truth is heartworm can be found in all 50 states in the United States.

The good news is heartworm prevention is very easy. The American Heartworm Society recommends the ‘Think 12’ method. This method encourages owners to get their animal tested every 12 months and to give their pet heartworm preventative 12 months a year.  Heartworm disease is a very serious, progressive disease; the earlier that it is detected the better the chances of recovery. Signs of heartworm disease may include mild persistent cough, fatigue, decreased appetite, and weight loss.

With the weather getting warmer here in Fort Collins, and the mosquitos coming out, now is the perfect time to get your pet tested and put on preventative medicine.

Blog by Nicole Lathrop, senior at Colorado State University


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