What diseases can ticks pass to dogs?
When an infected tick bites a dog, it can transmit several serious illnesses. Most common diseases dogs can get from ticks include:
- Anaplasmosis: May cause fever, limping, bruising, or bleeding problems.
- Lyme disease: Can lead to limping, stiffness, low energy, or swollen lymph nodes.
- Ehrlichiosis: May cause fever, weight loss, enlarged lymph nodes, bruising, or bleeding problems.
In some cases, tick-borne diseases can lead to more serious problems, such as kidney failure, nervous system issues, and even death. Understanding how the risk of exposure to ticks and the diseases they carry is changing can help keep your dog healthy and is an important step in protecting their long‑term health.
Why is the risk of tick-borne diseases changing?
The risk of tick-borne diseases is changing because ticks haven't stayed in one confined area. Instead, the geographic range where they live is slowly changing over time, and with it, so are the diseases they carry.
Many things can cause ticks to migrate to new areas, such as:
- Changing landscape: If a wooded area is cut down, the ticks inhabiting that area may shift to a new location. On the other hand, reforestation (planting trees to restore forests) can provide new areas for ticks to move into.
- Wildlife movement: In addition to dogs, ticks feed on wild animals, such as rodents and deer. If these animals move to a different area, ticks may follow them.
- Movement of people and pets: As people travel with pets and animals are relocated, infected ticks can be carried into new areas.
- Climate changes: Different types of ticks prefer different climates, with some liking cooler areas and others liking hot, humid areas. As weather patterns change, ticks may move into new areas that were previously unsuitable for them.
Also, ticks don't die off during the cold winter months, as many people assume. They hide in leaf litter and brush piles and emerge when warmer weather returns. As winter temperatures become milder, ticks can emerge during warmer days, or they may be active all year long.
As ticks move into new areas and emerge year-round, the rate of tick-borne diseases in those areas increases. This means that dogs living in areas previously considered low risk may now be more likely to get a disease spread by a tick.
How to stay informed about the changing threat of tick-borne diseases
Tick‑borne diseases are on the move. Keeping an eye on where they’re showing up can help you and your veterinarian understand whether your dog may be at risk.
For example, when more dogs are diagnosed with a disease like Lyme disease in an area that’s usually considered low risk, it’s often a sign that infected ticks have moved into that region. As ticks spread, the risk to dogs can increase, sometimes faster than people realize.
The great news is there are resources to help you learn where the risks are.
The Companion Animal Parasite Council (CAPC) is an organization that was started to keep pet owners and vets informed about parasites and the diseases they cause. CAPC gathers data on diseases spread by ticks, including where positive tests for certain diseases occur, and shares it through Parasite Prevalence Maps, which are free and available to the public.
Using CAPC’s Parasite Prevalence Maps
CAPC’s interactive maps show where dogs are testing positive for diseases spread by ticks across the United States. This provides an estimate of regional risk by displaying the percentage of tested dogs that receive a positive result in each area.
With these maps, pet owners can:
- Select a specific disease and year (from 2012 through 2026).
- See how the risk in different areas has changed over time.
- Zoom in from the state level down to individual counties.
- See how many tested dogs have received a positive result in each county of their state.
By monitoring where dogs test positive and how disease distribution changes over time, you and your vet can estimate the risk for dogs in their areas. Your veterinarian can help you interpret this information, discuss the risks, and recommend the best ways to protect your dog.
How to know if your dog is at risk for tick-borne diseases
CAPC's Parasite Prevalence Maps can also tell you which diseases have been found where you live. The disease risk of a specific area depends on which ticks are found there.
For example:
- Lyme disease is spread by blacklegged ticks (also called deer ticks), which live mainly in the New England and Upper Midwest states—making these areas the highest risk.
- Ehrlichiosis is diagnosed most commonly in Southern states, where lone star ticks are commonly found; however, brown dog ticks can also transmit Ehrlichia and are found throughout the United States.
How often your dog is exposed to ticks also plays a role. Dogs who spend more time in areas where ticks are found, like those who go camping or hiking, are more likely to encounter a tick than dogs who spend most of their time inside. While ticks can latch onto any dog, shaggy breeds and those with longer fur may be more likely to brush up against leaves and other hiding spots, allowing ticks to attach. Ticks might also be harder to find and remove on longhaired dogs.
Although outdoor activities increase a dog's risk, ticks aren't only found in the woods. They can also be found in tall grass, brush, and backyards. Some tick species make their homes indoors. This is why tick prevention is important for all dogs.
How to protect your dog from diseases carried by ticks
Steps you can take to keep your dog healthy include:
- Provide year-round tick prevention: Since ticks can be active all year long, it's important to provide continuous protection for pets. Talk to your vet about safe products and methods they recommend.
- Get rid of tick hiding spots: Clean up leaf litter, wood piles, and brush in your yard, and keep your grass cut short.
- Perform routine tick checks: Check your dog's entire body any time they are in areas where ticks live, such as the woods or tall grass.
- Remove ticks: If you find a tick on your dog, remove it immediately. If you aren't able to remove the tick, the area becomes red or inflamed, or your dog isn't acting like themselves, schedule an appointment with your vet.
- Regularly screen your dog for disease: Testing for diseases spread by ticks is recommended annually to help catch problems early, before there are noticeable signs or symptoms.
- Vaccinate your dog for Lyme disease: Vaccination is typically recommended for dogs at high risk of exposure to tick-borne diseases. Talk to your vet about whether your dog should be vaccinated for Lyme disease.
- Keep track of disease patterns: Since the risk of diseases spread by ticks changes as ticks move into new areas, it's important to check the CAPC Parasite Prevalence Maps on a regular basis.
One of the best ways to keep your dog safe and healthy is to be proactive! Your vet can help you with preventive medications or other methods and provide recommendations based on your dog's specific risks.
Final thoughts: Staying aware of changing tick-borne disease risk
Although the risk of diseases spread by ticks can change, staying on top of current information can help you know if your dog is at greater risk, and help you keep them as healthy as you can. Remember that your vet is your partner in protecting your pet's health. They can help you understand which diseases your dog could be exposed to and how to keep them healthy.
Frequently asked questions
Frequently asked questions about this topic
Dogs are more likely to encounter ticks in places like the woods and high grass, but these ticks can be found in backyards. Some tick species even live inside. This means any dog can be exposed to ticks.
Many diseases spread by ticks don't cause obvious signs, so even dogs who seem healthy can be exposed. Yearly testing can help identify exposure or infection and support timely care if needed.
If your dog is on year-round parasite prevention that includes tick control, their risk of getting a tick-borne disease is lower. However, ticks are sometimes found on dogs that take preventive medication. This means you should still take other safety measures, such as performing tick checks and staying up to date on disease risk in your area, to reduce their risk as much as possible.
