can cats get heartworm

Cats can get heartworm disease, but they are less commonly affected than dogs and are considered an imperfect host. Heartworm disease in cats is caused by the parasite Dirofilaria immitis, which is spread by mosquitoes. While cats can become infected, only a smaller percentage of the worms reach adulthood in cats compared to dogs, and cats typically have fewer worms—often only one to four. The infection in cats often leads to a condition called Heartworm Associated Respiratory Disease (HARD), which causes respiratory symptoms like coughing, wheezing, and difficulty breathing. The disease progression in cats is different from dogs; many immature worms die before reaching maturity, but the dying worms can cause significant lung inflammation and damage. Adult heartworms in cats live for about 2 to 4 years and even a single worm can cause severe and potentially fatal lung disease. Cats get heartworm exclusively through mosquito bites that carry infective larvae; it is not transmitted directly from dogs to cats or from cat to cat. Since cats are less ideal hosts, the overall infection rate in cats is much lower than in dogs (approximately 5–20% of the infection rate seen in dogs in the same area).