Lyme disease is a bacterial infection transmitted by ticks but rarely seen in cats. Exposed cats do not always develop the symptoms seen in dogs and humans, and diagnosis can be tricky. Lyme disease can lead to fever, lethargy, and poor appetite. The right treatment can make your cat feel better in a short amount of time. Read on to learn about the symptoms, causes, risk factors, treatment, and prevention of Lyme disease in cats.

What Is Lyme Disease?

Lyme disease is a tick-borne disease caused by an infection of Borrelia burgdorferi bacteria. The disease affects many species, especially humans and dogs, but it rarely affects cats. It has been shown that cats can become infected with Borrelia burgdorferi bacteria, but many 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 can become infected with Borrelia burgdorferi without 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

The symptoms of Lyme disease in cats are similar to those in dogs and humans, though not as severe. Signs typically begin to appear within a few weeks after infection.

Contact your veterinarian if your cat develops these symptoms during the warm weather season when ticks are most active. Many other tick-borne diseases can affect cats, and most are prevalent in the northeastern portion of the United States. One illness, called anaplasmosis, occurs in cats and leads to fever, lethargy, and 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 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 lethargic and lose their appetite. The bacteria can also affect the heart, causing extreme exhaustion.

Secondary Kidney Disease

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

What Causes Lyme Disease in Cats?

Lyme disease is caused by the bacteria Borrelia burgdorferi. Ticks become infected with this bacteria by feeding on infected mice and other small animals. They then transmit the bacteria when biting other animals.

Lyme disease is transmitted by the deer tick (also called Ixodes scapularis or the black-legged tick) and some 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. Ticks can be carried into yards on other animals, so even cats that don't roam far can be bitten by a tick. Ticks are frequently found on dogs and can hitch a ride into the home to bite an indoor pet cat. There is no evidence that Lyme disease is spread by direct contact between animals, nor between infected pets and their owners.

How Vets Diagnose 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 some time after exposure.

Your veterinarian 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
• Sampling of joint fluid

How to Treat Lyme Disease in Cats

Lyme disease is typically treated with antibiotics. In dogs with Lyme disease, antibiotic treatment 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 is usually necessary, along with additional treatments. Your vet will develop a treatment plan 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 occur. 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 steps to keep your pet healthy:

Tick Removal and Handling

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.

Tick Prevention

Several preventive tick treatments for cats are available and should be used in at-risk cats. Be sure to follow your veterinarian's advice when using these products because cats are sensitive to several chemicals.

Yard Maintenance

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.​​