Tick-Borne Diseases in Dogs and Cats

While Southern California isn't known for having as many ticks as other parts of the country, dogs and cats in Los Angeles County are still at risk for tick bites and tick-borne diseases. Pets that hike in the Santa Monica Mountains, Angeles National Forest, Griffith Park, the Verdugo Mountains, local foothills, or other brush-covered areas are especially vulnerable. As tick populations continue to expand throughout California, year-round prevention is becoming increasingly important.

Where Do Pets Pick Up Ticks?

Ticks thrive in tall grass, brush, leaf litter, and wooded areas. They wait on vegetation until an animal brushes past, then attach and begin feeding. Even pets that spend most of their time indoors can occasionally bring home ticks after spending time in a backyard, neighborhood park, or on hiking trails.

The Western black-legged tick, the primary tick species found in California, is capable of transmitting several infectious diseases to pets.

Common Tick-Related Medical Problems

Lyme Disease

Although Lyme disease is less common in Southern California than in the northeastern United States, it does occur in California. The disease is caused by the bacterium Borrelia burgdorferi and is transmitted by infected ticks.

Dogs with Lyme disease may develop:

• Fever

• Limping or shifting leg lameness

• Swollen, painful joints

• Lethargy

• Loss of appetite

• Swollen lymph nodes

In rare cases, Lyme disease can lead to kidney damage if left untreated. Lyme disease is uncommon in cats, and clinical illness is rarely diagnosed.

Anaplasmosis

Anaplasmosis is one of the more frequently diagnosed tick-borne infections in California dogs. It can also affect cats, although this is much less common.

Signs may include:

• Fever

• Joint pain

• Stiffness

• Decreased appetite

• Vomiting

• Lethargy

Most pets recover well when treatment begins early.

Ehrlichiosis

Ehrlichiosis is another bacterial infection spread by ticks and is occasionally diagnosed in Southern California. Clinical signs may not appear until several weeks after the tick bite.

Symptoms include:

• Fever

• Weight loss

• Low energy

• Pale gums

• Bruising or bleeding

• Enlarged lymph nodes

• Joint pain

Without treatment, ehrlichiosis can become a chronic illness that affects the immune system and bone marrow.

Tick Bite Reactions and Skin Infections

Many pets experience localized irritation where a tick attaches. The bite area may become red, swollen, itchy, or infected if the pet scratches or chews excessively.

Although these reactions are usually minor, they should be monitored closely for worsening redness, swelling, or discharge.

How Veterinarians Diagnose Tick-Borne Diseases

If your pet becomes ill after tick exposure, your veterinarian will perform a physical examination and discuss recent outdoor activities or travel.

Diagnostic testing may include:

• Complete blood count (CBC)

• Blood chemistry panel

• Urinalysis

• Tick-borne disease screening tests

• Additional laboratory testing to identify specific infectious organisms when needed

Because many tick-borne diseases share similar symptoms, laboratory testing helps determine the most appropriate treatment plan.

Treatment Options

Treatment depends on the disease and the severity of illness. Most bacterial tick-borne infections respond well to antibiotics when diagnosed early.

Additional treatment may include:

• Pain relief for sore joints

• Anti-inflammatory medications when appropriate

• Intravenous fluids for dehydration

• Hospitalization for pets that are severely ill

• Supportive care until the infection resolves

Most pets improve significantly within several days of starting treatment, although follow-up testing may be recommended.

Protecting Your Pet from Ticks

Fortunately, tick prevention is highly effective. Southern California pet owners can reduce their pet's risk by:

• Using veterinarian-recommended year-round flea and tick prevention

• Checking your pet thoroughly after hikes or walks through brushy areas

• Paying close attention to the ears, neck, face, armpits, between the toes, and under the collar

• Keeping landscaping trimmed to reduce tick habitat around your home

• Removing ticks promptly using a tick-removal tool or fine-tipped tweezers

When Should You Visit a Veterinarian?

Schedule a veterinary examination if your dog or cat develops fever, limping, weakness, decreased appetite, swollen joints, unusual bruising, or lethargy after spending time outdoors or after a tick bite.

Even if you remove the tick successfully, your veterinarian may recommend monitoring or testing if your pet develops symptoms in the following days or weeks.

With routine tick prevention, regular tick checks after outdoor adventures, and early veterinary care, most tick-related illnesses can be prevented or treated successfully. Whether you're hiking the local trails, visiting the beach canyons, or simply enjoying your neighborhood park, protecting your pet from ticks is an important part of keeping them healthy year-round.

Questions about Your Pet’s Health? 

Schedule an appointment with your primary care veterinarian or visit our Burbank or Koreatown location if your pet has concerning symptoms. 

Call us at (818) 296-0700 in Burbank or (323) 302-5200 in Koreatown to speak with a member of our care team. We’re here to help for your furry loved one’s medical needs!