According to federal data and experts, this year’s tick season could be one of the worst on record.
The Centers for Disease Control and Prevention’s tick bite data tracker, which uses real-time emergency room monitoring, shows that weekly tick-bite ER visits are higher than the historical average in every U.S. region except south central states, with the Northeast recording the highest level so far in 2026.
The CDC said that during the fourth week of April, about 114 out of every 100,000 emergency department visits nationwide were for tick bites — the highest rate at this point in the year since at least 2017. Nationally, the agency estimates that about 31 million people are bitten by ticks each year, and about 476,000 Americans are treated annually for Lyme disease, the most common tick-borne illness.
“Tick season is here and these little biters can make you seriously ill,” said Dr. Alison Hinckley, an epidemiologist and Lyme disease specialist in CDC’s Division of Vector-Borne Diseases. “This means ticks are out and people are being bitten, so now is the time for people to take steps to protect themselves and their loved ones.”
While the CDC only tracks ER visits related to tick bites — not tick bites or the presence of ticks overall — the increase indicates that weather patterns, normal year-to-year variation in tick survival, and the geographic expansion of tick populations may have resulted in one of the most abundant tick-bite seasons in recent memory.
Is tick season coming earlier?
Tick season was once shifted to the hot summer months. According to Dr. Jim Fredericks, chief entomologist for the National Pest Management Association, that is no longer the case.
“As we see this trend during these mild winters and the shorter seasons this spring, it looks like it’s going from winter to summer,” he said. “This allows a large proportion of the tick population to survive the winter, even in places where there is snow cover.”
The earlier arrival and longer duration of warm weather makes it possible for ticks to be prevalent almost all year round in some areas. And with that layer of ice you can expect to kill them? It serves as a more comfortable blanket.
“Ticks actually do better when there is more snow rather than less because a snowpack is insulating for them,” said Dr. Katherine Reiff, associate professor of parasitology at Auburn University’s College of Veterinary Medicine. “They’re in that dead layer of plant material where they’re completely warm.”
Why is tick season so bad this year?
In addition to the relatively mild winter and the snow-blanket effect, experts also point to what they call the “acorn effect.”
Wildlife that frequent acorns – deer, mice and squirrels – feed on acorns each fall. Oak trees do not produce the same crop every year; Instead, they follow an irregular cycle. A year with heavy acorn production is called an “excellent year,” Fredericks said, and the U.S. has seen several large-scale productions recently.
When small mammals can eat from an abundant food source and reproduce more, more ticks can use them as hosts.
“If our wildlife is healthy and they have plenty of food, it can certainly create more of them, which now has more hosts for these ticks to eat,” Reiff said.
And because ticks acquire the diseases they carry from mammals like chipmunks, rats and squirrels – not by birth – more of those animals means a greater chance of disease transmission.
tick-borne diseases persist
Lyme disease is often the first disease that comes to mind in association with ticks, but experts say ticks are carrying more disease-causing organisms than previously recorded.
Ehrlichiosis, anaplasmosis, Rocky Mountain spotted fever, babesiosis, tularemia, and tick paralysis are all diseases that can spread between humans and pets.
Lyme, ehrlichiosis and anaplasmosis are particularly prevalent in dogs and their owners, Reiff said. Their prevalence is also expected to increase in 2026, according to the Companion Animal Parasite Council, which estimates the prevalence of the disease in dogs with more than 94% accuracy.
Ehrlichiosis and anaplasmosis usually cause flu-like symptoms initially, but if untreated can lead to respiratory and organ failure, excessive bleeding, central nervous system damage, and death. Lyme is more diverse, with symptoms ranging from fever and rash to facial paralysis, irregular heartbeat, and arthritis.
“We have traditional hot spots where these tick-borne diseases are most common. And as the years go by, these areas never really shrink – they just keep expanding,” Reiff said. “These are definitely ongoing diseases.”
How to protect yourself from tick bites
Prevention is key when it comes to ticks.
If you have property, consult a pest-control specialist to tick-proof the space — which may include putting up barriers between the lawn and wildlife-access areas, keeping grass short and planting repellents, Fredericks said.
If you have pets, talk to your veterinarian about flea and tick prevention, annual checkups and Lyme disease vaccinations, Reiff said.
If you spend time outside, you should:
- Wear insect repellent.
- Cover exposed skin with clothing and appropriate footwear.
- As soon as you return home, take off your clothes and do a thorough examination.
After coming inside, you should also carefully examine your body. Ticks seek out warm, hidden areas of the body – pay special attention to hair, ears, back, underarms, groin, navel, groin, knees and between toes.
Reporting by Mary Walrath-Holdridge, USA TODAY.