Mosquitoes are often viewed as a nuisance for humans, but they pose a genuine health risk to cats. The answer to whether mosquitoes bite cats is a definitive yes, and these bites are more than just an itchy irritation. While a cat’s fur offers some protection, mosquitoes easily find thinly covered areas to feed. This act can transmit a dangerous parasite, making mosquito prevention a serious consideration for all cat owners.
Do Mosquitoes Really Bite Cats
Mosquitoes are attracted to the carbon dioxide and body heat of mammals, and they readily bite cats despite their coat. The insects target areas where the fur is sparse, such as the bridge of the nose, the tips of the ears, the paw pads, and the abdomen. Even indoor cats are at risk, as mosquitoes easily enter a home through open doors, windows, or damaged screens.
The immediate reaction to a bite can range from a small, localized swelling to a more severe allergic response. Some cats develop Feline Mosquito Hypersensitivity, an intense immune reaction to the proteins in the mosquito’s saliva. This hypersensitivity causes crusted, ulcerated lesions, particularly on the nose and ear tips. These lesions may be mistaken for other skin conditions and are often accompanied by intense itching, hair loss, and sometimes fever or swollen lymph nodes.
The Main Danger Heartworm Disease
The most significant danger associated with a mosquito bite is the transmission of heartworm disease, caused by the parasite Dirofilaria immitis. The mosquito acts as an intermediate host, picking up immature heartworm larvae, called microfilariae, from an infected animal, most commonly a dog. When that infected mosquito subsequently bites a cat, it injects the infective larvae into the cat’s bloodstream.
Cats are considered resistant hosts, meaning the infection often does not progress to the adult stage as it does in dogs, and they typically harbor fewer worms. However, even the death of immature worms in the pulmonary arteries can trigger a severe inflammatory response. This reaction is known as Heartworm Associated Respiratory Disease (HARD), which causes damage to the lungs and small airways.
Symptoms of heartworm disease in cats are often subtle and non-specific, making diagnosis challenging. Common signs include intermittent vomiting, coughing, rapid breathing, and weight loss, which can be easily misdiagnosed as feline asthma or bronchitis. In some cases, the first sign of infection is sudden collapse or death, which occurs when adult worms die and cause acute respiratory distress and shock.
Unlike in dogs, there is no approved medication to kill adult heartworms in cats, as the drug used for dogs is toxic to felines. Treatment focuses on supportive care, such as using corticosteroids to manage the inflammation caused by HARD. Since diagnosis is difficult and a safe adulticide treatment is lacking, prevention is the only reliable way to protect a cat from this potentially fatal disease.
How to Protect Your Cat
The most effective strategy for protecting a cat from heartworm disease is year-round prevention with a veterinarian-prescribed product. The American Heartworm Society recommends continuous use of preventatives, even for indoor cats, because mosquitoes can easily enter a home and transmit the parasite. These medications, available as oral tablets or topical spot-ons, work by killing the heartworm larvae transmitted in the previous month before they can mature.
Environmental control is another element of protection to reduce mosquito exposure. Cat owners should ensure that all window and door screens are intact to prevent mosquitoes from entering the living space. Eliminating sources of standing water, such as old tires, clogged gutters, or frequently changed water bowls, removes potential breeding grounds near the home.
It is important to avoid using human or dog-specific insect repellents on cats, as many contain ingredients that are highly toxic to felines. Products containing DEET (N, N-diethyl-meta-toluamide) can cause severe neurological symptoms, including tremors and seizures. Similarly, dog-specific flea and tick products often contain permethrin, which is toxic and potentially fatal to cats. Always consult a veterinarian for advice on cat-safe mosquito repellent options.