Tick season has barely started, and the CDC is already sounding alarms. Emergency room visits for tick bites are running at the highest rates the agency has tracked at this point in spring since 2017 — and the most dangerous stretch of the year for dogs hasn't even arrived yet.
According to the CDC's Tick Bite Data Tracker, every region in the country except the South Central states is logging above-normal weekly tick-bite ER visits. The Northeast is leading the surge: emergency department visits there were up 40% this April compared to the same month last year. Roughly 476,000 Americans are treated for Lyme disease every year, and our dogs — closer to the grass, often sniffing through hedgerows and forest understory — are even more exposed.
For dog owners, the practical question is simple: what should I be doing right now, and how worried should I actually be?
What the 2026 outlook says
Each spring, the Companion Animal Parasite Council (CAPC) publishes a national pet parasite forecast that has historically been more than 94% accurate at predicting county-level disease prevalence. Its 2026 outlook is not subtle. Lyme disease risk continues to climb across the Upper Midwest and Northeast, with new expansion projected into Ohio, Kentucky, West Virginia, and parts of Tennessee and North Carolina. Anaplasmosis is following the same blacklegged tick range — including a growing footprint up the West Coast from northern California through Oregon and Washington. Ehrlichiosis remains stubbornly high across the Southeast, Southwest, and coastal Atlantic states, with new ground gained in Arizona, New Mexico, Colorado, Utah, and Wyoming.
Translation: there are very few places left in the continental U.S. where you can credibly tell a dog owner, "you don't really have to worry about ticks here."
The poppy-seed problem
The reason the next 60 days matter most isn't because there are more ticks in late spring — it's because nymphal blacklegged ticks are about to emerge in force. CDC epidemiologist Alison Hinckley put it bluntly to reporters: "Tick season is here and these tiny biters can make you seriously sick."
An adult deer tick is about the size of a sesame seed. A nymph is the size of a poppy seed. They're roughly the diameter of the period at the end of this sentence, and on a dog with a thick coat, they're almost impossible to spot before they've latched on.
That stealth is biological, not accidental. Northeastern University tick researcher Constantin Takacs has explained that deer ticks deploy a cocktail of proteins that locally suppress the immune response and dampen nerve sensitivity at the bite site. As Takacs told Northeastern Global News, "There's no pain and there's no swelling or itchiness," which lets ticks feed undisturbed for the 24-plus hours generally required to transmit pathogens like Borrelia burgdorferi, the bacterium that causes Lyme.
The peak nymphal window in the Northeast and Upper Midwest typically runs from mid-May through mid-July. If you have ever wondered why "tick season" suddenly feels like it gets serious right around Mother's Day, that is why.
What ticks actually do to dogs
Most owners hear "Lyme disease" and picture the bull's-eye rash people get. Dogs don't get the rash, and that's part of what makes canine Lyme dangerous: it's quiet. According to the American Veterinary Medical Association, only 5% to 10% of infected dogs ever go on to develop visible signs of illness — but when they do, symptoms typically don't appear until two to five months after the tick bite, long after the bite itself has been forgotten.
The classic canine Lyme symptoms are:
- Shifting-leg lameness — limping that moves from one limb to another
- Fever and reduced appetite
- Lethargy or general "not himself" behavior
- Swollen lymph nodes
- Joint pain and swelling
The AVMA also notes that 1% to 5% of infected dogs go on to develop Lyme nephritis, a kidney disease that can cause weight loss, vomiting, and diarrhea. Lyme nephritis is the version of canine Lyme that most often kills, and it can develop in dogs who never showed any joint symptoms at all.
Anaplasmosis, the second most common tick-borne disease in U.S. dogs, looks a lot like Lyme on presentation: lethargy, fever, joint pain, sometimes thrombocytopenia (low platelets) that shows up only on bloodwork. Ehrlichiosis tends to look similar but is more common in the Southeast and Southwest. And in many parts of the country, dogs who get one tick-borne infection are also at risk for picking up a second.
What prevention actually looks like in 2026
Year-round tick prevention is the baseline — not seasonal, not "May through October." Warmer winters across most of the U.S. now allow ticks to be active during any month with a few mild days in a row, and CAPC's 2026 forecast explicitly calls out year-round transmission as the new normal.
Beyond a vet-prescribed oral or topical preventive, the protocol is unglamorous but effective:
- Daily tick checks. Ears (inside and the base), under the collar, around the eyes, between the toes, in the armpits, around the tail and groin, and anywhere a tick can hide in a fold of skin. After a hike, do it twice.
- Avoid high-risk terrain in May–July. Tall grass, leaf litter, marsh edges, and the brushy borders between woods and lawn are nymph hot zones. Trails that stay in the open are dramatically lower risk.
- Yard maintenance. Keeping grass short, clearing leaf piles, and creating a 3-foot wood-chip or gravel barrier between lawn and woods sharply reduces tick density at home.
- Remove attached ticks within 24 hours. Use fine-tipped tweezers, grasp at the skin, pull straight out, then disinfect. The 24-hour transmission window is your main margin.
- Annual screening. A 4Dx blood test at your dog's wellness visit screens for heartworm plus Lyme, anaplasmosis, and ehrlichiosis exposure — often catching infections before symptoms.
The Lyme vaccine for dogs is a non-core vaccine, meaning your vet will recommend it (or not) based on your dog's lifestyle and where you live. VCA Animal Hospitals notes that the vaccine reduces risk but isn't 100% effective and is best understood as one layer in a strategy, not a replacement for tick preventives. PetMD recommends it especially for dogs in high-prevalence areas — most of the Northeast and Upper Midwest at this point — or dogs who spend significant time in wooded or grassy environments.
When to call the vet
If you find a tick, remove it and note the date. If your dog develops shifting-leg lameness, runs a fever, stops eating, or seems "off" in the weeks or months that follow, mention the tick bite to your vet specifically — the lag between bite and symptoms is what makes canine tick-borne illness easy to miss. And if you ever see vomiting, weight loss, or excessive thirst and urination after a known tick exposure, treat it as urgent: those are early signs of Lyme nephritis.
Spring is loaded with hidden hazards for dogs — we've covered foxtail awns and pollen-driven allergy flares in the past two weeks alone. Ticks are different in one important way: the damage they cause may not show up for months, by which time the bite is long forgotten. The dog owners who come through 2026 unscathed will be the ones who treat tick prevention the way they treat heartworm prevention — quietly, every month, all year.
Your dog can't tell you they got bitten. The best thing you can do this week is run your hands through their coat after every walk, talk to your vet about your county's risk profile, and put tick prevention on autopilot for the rest of the year.
