Climate change isn’t just about warmer temperatures—it’s fundamentally changing where and when ticks thrive, which means tick-borne diseases like Lyme disease are appearing in new areas and lasting longer through the year. Understanding these shifts helps you protect yourself and your family.
Here’s what’s happening and what it means for your health.
Ticks Are Moving North
Warmer winters allow ticks to survive in regions that were previously too cold. Areas that rarely saw ticks 20 years ago now have established populations.
Black-legged ticks that carry Lyme disease have expanded their range significantly northward into Canada and higher elevations. If you live in an area where Lyme disease was once rare, that might not be true anymore.
I’ve diagnosed Lyme disease in patients who never thought they were at risk because they didn’t live in “tick country.” The map of tick country is redrawing itself.
Longer Active Seasons
Ticks used to be mainly a spring and early summer concern. Now, with warmer falls and milder winters, tick season stretches from early spring through late fall in many regions.
Some areas see tick activity year-round during warm spells in winter. You can’t let your guard down in October or November anymore like you might have in the past.
This extended season means more opportunities for tick bites and disease transmission throughout the year.
Increased Tick Populations
Warmer temperatures and changing rainfall patterns create ideal conditions for tick reproduction and survival. Tick populations are growing in many areas.
More ticks mean more chances of encountering them during outdoor activities. Areas that had light tick pressure now have heavy infestations.
Deer and rodent populations—the hosts ticks depend on—are also affected by climate change in ways that can increase or decrease tick abundance in different regions.
New Diseases Emerging
As ticks expand their range, they bring diseases with them. Some tick-borne illnesses that were confined to specific geographic areas are spreading.
Powassan virus, a rare but serious tick-borne disease, is appearing in new locations. Other pathogens are emerging as warmer conditions allow different tick species to thrive.
The relationship between climate and disease is complex, but the overall trend points toward increased risk in more places.
What This Means for You
Check for ticks after any outdoor activity, regardless of season or location. Don’t assume you’re safe because ticks weren’t a problem in your area before.
Use insect repellent containing DEET, picaridin, or permethrin on clothing. Wear light-colored clothing so ticks are easier to spot. Tuck pants into socks when hiking in wooded or grassy areas.
Do thorough tick checks on yourself, children, and pets daily during warm months. Pay attention to hidden spots—behind knees, in hair, armpits, groin.
Recognizing Tick-Borne Illness
Know the signs of Lyme disease—the expanding bull’s-eye rash appearing days to weeks after a bite, fever, headache, fatigue, and muscle aches.
Other tick-borne diseases cause similar symptoms. Any unexplained fever, rash, or flu-like illness following time outdoors should prompt medical evaluation.
Through telemedicine, I can assess your symptoms and photos of any rashes. Early antibiotic treatment for Lyme disease prevents serious complications.
The Bigger Picture
Climate change is creating a new normal for tick-borne disease risk. Staying informed about tick activity in your area, taking preventive measures seriously, and seeking prompt evaluation for potential tick bites are more important than ever.
Public health officials are tracking these changes, but individual awareness and prevention remain your best defense against tick-borne illnesses in our changing climate.
