Heartworm is a disease caused by worms that live in the heart and lungs of dogs and cats.
Heartworm can lead to lung disease, heart failure and damage to other organs.
Mosquitoes can carry and transmit the disease between pets. Other animals, such as ferrets, can contract heartworm as well.
According to the American Heartworm Society, baby worms in affected pets can be picked up by mosquitoes. When the worms develop into infective larvae, they can be passed on to other animals through bites.
It can take up to six months for the larvae to mature, and they can live for five to seven years in dogs and two to three years in cats once mature, the Heartworm Society said.
In the early stages of the disease, signs may not be obvious in dogs. According to the Heartworm Society, visible signs may include a mild but persistent cough, decreased appetite, weight loss and fatigue.
Dogs with many heartworms may develop blockages of blood flow within the heart. This could result in a cardiovascular collapse. Signs of this include labored breathing, pale gums and dark bloody or coffee-colored urine, according to the Heartworm Society.
The signs of heartworm in cats can include coughing, asthma-like attacks, periodic vomiting, a lack of appetite or weight loss. Cats may also have trouble walking, have seizures or faint, or get fluid in their abdomen.
According to the Heart Society, dogs should be tested annually for heartworms. Cats should be tested before beginning prevention and retested at a veterinarian’s discretion.
If a pet tests positive for heartworm, treatments can be given to dogs. Exercise should be limited in an affected dog. There is no approved treatment for cats, according to the Heartworm Association, though a vet can help stabilize the cat.
Pets should be on preventative medication that can be prescribed by a vet.