Can a mosquito infect a dog with a deadly disease? Unfortunately the answer is yes and this happens repeatedly every year to dogs in Canada, the United States and worldwide.
Our beloved family dog is what is called the “natural host” for heartworm, and that means that this foot long adult worm can establish itself and breed in your dog’s heart and blood vessels. Other animals such as cats, ferrets and foxes, coyotes and wolves can be infected and the dog’s wild relations are thought to be a source of infection for the domestic dog. The mosquito takes a blood meal from an infected animal and then spreads the disease to uninfected individuals with subsequent blood meals. The small larval form that infects the dog, matures in the body tissues and sets up shop as an adult in the heart to mate and produce offspring and keeps the cycle going. As the parasite colony grows in the heart, problems with heart function and circulation occur. These signs look like a reduced ability to exercise, a cough and even sudden death.
Heartworm disease can be treated but the risks and costs can be substantial. This is a problem that is best prevented. The prevention program consists of annual testing of dogs 7 months or older and the prescription by a veterinarian of the product that best suits your dog’s lifestyle and needs. Many heartworm prevention products have other benefits such as flea prevention and/or internal parasite control as well.
The American Heartworm Society (AHS) has an excellent resources. Lifetime member of the AHS, Dr William C. Campbell has been awarded the Nobel prize in 2015 for his work that involves the family of worms that heartworm belongs to and drugs that can be used to manage infection. The web based resource does an excellent job describing the life cycle and also has important information about how heartworm can affect our cats as well. Education about heartworm is one of our best defences against this deadly scourge !