North Haven, CT (April 28, 2018) The Animal Haven in North Haven wants to inform the community about the dangers of heartworm disease to companion animals. Heartworm is spread from animal to animal by the mosquito. It primarily affects dogs, though cats can contract the disease; symptoms include a chronic cough, exercise intolerance, poor appetite, weight loss, and a visibly distended abdomen. A simple blood test performed by your pet’s veterinarian can determine infection.
"Heartworm disease is a constant and serious threat to dogs and some cats in Connecticut," says Animal Haven Board member and retired veterinarian Dr. Arnie Cary. "In recent years the influx of dogs for adoption from Gulf states where there is a very high incidence of the disease has drastically increased the potential for infection in our already heartworm-prone state."
According to the American Heartworm Society: Adult female heartworms (foot long worms that live inside the heart) in an infected dog, fox, coyote, or wolf produce microscopic baby worms called microfilaria, that circulate in the bloodstream. When a mosquito bites, it ingests these baby worms which molt or mature in the mosquito over 10-14 days into “infective larvae”. When the mosquito then bites another dog (or the same dog), a cat, or susceptible wild animal, the larva enters the bloodstream and grows into an adult worm (over a period of about 6 months).
Symptoms of infection in a dog are caused by poor blood flow through the heart and lungs from the presence of worms and some inflammation inside the bloodstream. Symptoms in the cat may be vague, or sometimes dramatic. The cat is not a primary natural host, so an immune response can in many cases thwart the growth of the larva to adulthood. But it can occasionally happen if the dose of larvae is a large one. Vague respiratory symptoms may occur, or sometimes sudden collapse and death. Infection, though rare, can occur even in indoor cats.
A blood test is used to detect heartworm. It tests for the presence of adult heartworm proteins. If there are adult female heartworms, the test will be positive. If positive, treatment is suggested as early as possible. If negative, because it takes 6 months for adulthood to occur, it may be a false negative. As a consequence, yearly tests are suggested.
“Preventing heartworm is very easy and simple,” say Dr. Cary. “The newly acquired infective larvae are very susceptible to small doses of several safe and easy to administer medications for up to 45-50 days. If we dose with one of these medications once a month, we easily prevent the larvae from molting and becoming adults. If we miss a dose beyond 45 days, infection is likely to occur.” Once a month, every month, is generally the suggested way, according to the American Heartworm Society.
Pet owners can also take action to reduce the mosquito population around their livable space by eliminating standing water where mosquitos like to breed, by landscaping with mosquito-repellent plants, and by using bug lights outside and near entryways to the home. Other ways to deter mosquitos include application of pet and human-friendly mosquito repellents, using screening when sitting outdoors and fixing any tears or holes to prevent access inside the home.
Treatment for heartworms, once an infection has occurred, usually requires hospitalization and several injections of an adulticide medication. Complete rest at home for 6-8 weeks is suggested while the dead worms in the heart are dealt with by the body. It is a reasonably expensive procedure with some occasional side effects. Prevention is much preferred for the animal and one’s wallet.
Heartworm disease is a tropical disease gone awry in all 50 states now, including very definitely Connecticut. There are easy steps to test for and prevent this potentially fatal disease. Talk to your veterinarian about your dog and your cat before it’s too late. For additional information about heartworm disease, its prevention and treatment, visit www.heartwormsociety.org.
Animal Haven, Board President
Animal Haven, Board President