Lyme Disease in Cats

Lyme disease and the bacteria that causes it can be transmitted to cats through ticks though the illness is very rarely seen in felines. Cats do not always develop symptoms like dogs and humans, so diagnosis can be tricky. Lyme disease can lead to fever, lethargy, and a poor appetite but the right treatment can make your cat feel better in a short amount of time.

What Is Lyme Disease?

Lyme disease is a tick-borne illness that affects a variety of species and is commonly seen in humans and dogs. It has been shown that cats can become infected with Borrelia burgdorferi bacteria (the causative agent of Lyme disease), but many cats do not show signs of the disease. Nevertheless, it is a diagnosis to consider when cats have symptoms compatible with Lyme disease, especially in areas where Lyme disease is common, such as New England, New Jersey, New York, Maryland, Delaware, and even Pennsylvania, Wisconsin, and Minnesota.

Cats and dogs can become infected with Borrelia burgdorferi without ever developing symptoms of Lyme disease. Where Lyme disease is common, cats may test positive for exposure to the bacteria despite not showing any signs of the disease.

Symptoms of Lyme Disease in Cats

If a cat develops Lyme disease, the symptoms are similar to dogs and humans though not as severe, and they begin to appear within a few weeks after infection. If your cat develops these symptoms during the warm weather season when ticks are active, see your vet. It is important to note, however, that many other tick-borne diseases are prevalent in the northeastern portion of the United States that can affect cats. One illness, called anaplasmosis, occurs in cats and leads to fever, lethargy, and a poor appetite. It is also treated with antibiotics.

Limping

Because Lyme disease affects the joints and muscles, your cat may begin limping. The limping may shift from leg to leg as the cat tries to manage the discomfort. The limbs may begin to feel better, then pain recurs at a later date.

Stiffness and Pain

The infected cat may experience painful stiffness and pain around the joints and muscles. The limb joints may also be swollen.

Fever

A fever in a cat can indicate a number of maladies, including Lyme disease. Though it's best to let your vet take your cat's temperature with a thermometer, you can watch for fever symptoms, such as listlessness, shivering, or an increased breathing or heart rate. If the symptoms of a fever have not diminished, call your vet immediately.

Lethargy and Decreased Appetite

A cat with Lyme disease may act listless and lose its appetite. The bacteria could be affecting its heart, as well, which could cause extreme exhaustion.

Secondary Kidney Disease

If the Lyme is left untreated, a cat may experience kidney disease as the bacteria travels throughout the bloodstream. The kidney problems will lead to increased thirst, urination, and vomiting. The Lyme disease may be causing inflammation of the kidney which negatively affects the way it filters the cat's blood and toxins.

Causes of Lyme Disease

Ticks become infected with the Borrelia burgdorferi, bacteria by feeding on infected mice and other small animals. When an infected tick bites other animals, it can transmit the bacteria to these animals. Lyme disease is transmitted by the deer tick (also called Ixodes scapularis or the black-legged tick) and a group of other closely related ticks. The exact tick species varies by location, but the deer tick is small enough to bite animals and people without being easily detected.

Cats that spend a lot of time outdoors, especially in areas with bush or tall grass, are most at risk of being infected with Lyme disease bacteria. It is important to remember that ticks can be carried into yards on other animals, so even cats that don't roam far could potentially be bitten by a tick. Ticks are frequently found on dogs, so if you have a one, the tick can hitch a ride into the home on it and then bite an indoor pet cat. There is currently no evidence that Lyme disease is spread by direct contact between animals, including between infected pets and their owners.

Diagnosing Lyme Disease in Cats

Because so few cats develop symptoms after infection with Borrelia burgdorferi, a diagnosis of Lyme disease must be made on a combination of factors. An antibody test is not enough to make a diagnosis on its own because not all cats that are exposed to Borrelia burgdorferi get sick, and the antibodies can persist in the blood for a period of time after exposure. Your vet will use the following tools to help diagnose Lyme disease:

• History (especially exposure to ticks)
• Clinical signs
• Laboratory tests, such as blood, urine, and X-rays may rule out other causes
• A sampling of joint fluid

Treatment

In dogs with Lyme disease, treatment with antibiotics usually produces a rapid improvement in symptoms and the same should hold true for cats. If there are more serious issues that might be secondary to Lyme disease, such as kidney disease, a longer course of antibiotics along with additional treatments is usually necessary. Your vet will come up with a treatment plan that is aligned with your cat's needs and medical situation.

Prognosis for Cats With Lyme Disease

The prognosis for cats with Lyme disease is good. If the cat is treated in a timely manner, a full recovery should be fast. Delayed treatment can still lead to a good outcome, but it will take longer to achieve, and some tissue or joints may become irreversibly damaged and remain painful.

How to Prevent Lyme Disease

Tick control is extremely important for the prevention of Lyme disease (and other diseases that can be transmitted by ticks). This is true for both pets and humans. Take these three steps to keep your pet healthy:

• Remove ticks: Check outdoor cats daily for ticks and safely remove them as soon as possible. Pull back the fur and examine the cat at the skin level. A tick that is feeding will attach itself to the animal's skin, not to its fur. Since ticks must feed for at least 12 hours (possibly 36 to 48 hours) before transmitting the bacteria that causes Lyme disease, removing the tick as soon as possible can help prevent transmission. Be careful handling ticks as they can potentially infect people, too. It also helps to know that ticks do not jump around like fleas, though it may at first be tough to distinguish between the two bugs.
• Use correct products: Products that kill ticks should also be used in at-risk cats, but be sure to follow your veterinarian's advice when using these products, because cats are extremely sensitive or allergic to a variety of chemicals.
• Trim grass: Keep grass and brush trimmed in your yard and remove leaf litter and other materials where ticks may hide. You can also treat your yard for ticks if you live in a high-risk area.​​