Emergency rooms across the United States are seeing more patients for tick bites than at any comparable point in nearly a decade, and public health researchers say 2026 is shaping up to be one of the worst tick-borne disease years on record.
Emergency department visits for tick bites increased more than 25 percent in April 2026 compared to April 2025, according to CDC data cited at a Johns Hopkins Bloomberg School of Public Health media briefing on May 5, 2026. In concrete numbers, April 2026 saw 104 ER visits for tick bites per 100,000 total ER visits — up from 68 in April 2025, according to preliminary data from the CDC's Tick Bite Tracker.
July and August are the months when Lyme disease diagnoses peak across most of the United States. The tick season is not winding down — it is just getting started.
Why This Matters
Lyme disease is the most common vector-borne illness in the United States, and it is one of the most frequently misdiagnosed. Early infection is treatable with a standard course of oral antibiotics. Late-stage disease — which can involve the joints, heart, and nervous system — may require more intensive treatment and can produce symptoms lasting months or years even after antibiotic courses are completed.
Nicole Baumgarth, DVM, PhD, director of the Lyme and Tickborne Diseases Research and Education Institute at the Johns Hopkins Bloomberg School of Public Health, said the current data suggest the U.S. is in for a very bad year. She noted that the emergency room numbers represent only the tip of an iceberg, meaning the true burden of tick-borne illness is substantially higher than what ER visits capture.
The 25 percent increase in ER visits reflects only patients who sought emergency care. It does not capture the far larger number of people who were bitten, developed symptoms, saw a primary care doctor, or recovered without seeking care at all.
There is also a geographic dimension that makes this season different from prior years. Lyme disease is actively spreading into regions where it was once rare, and where clinicians and residents may not yet be thinking about it.
What We Know So Far
In all regions except the South Central United States, weekly rates of ER visits for tick bites in April 2026 were the highest for any April since 2017. The Northeast saw a 40 percent increase in tick-related ER visits in April compared to the same month in 2025, according to CDC data reported by multiple outlets.
The Pennsylvania Tick Research Lab at East Stroudsburg University reported testing 55 percent more ticks submitted for analysis in 2026 compared to 2025. In Connecticut, the state's tick testing program was receiving an average of 30 tick submissions per day, with greater than 40 percent testing positive for Lyme disease spirochetes.
The official CDC case count for Lyme disease in 2023 — the most recent year with final national data — was more than 89,000 confirmed cases. Researchers believe that number represents only a fraction of the real burden. The estimated true annual total approaches 476,000 Americans diagnosed and treated for Lyme disease each year, per the CDC.
Where the Risk Is Highest
As of April, the Northeast saw the largest increase in tick-related ER visits — rates far higher than in other parts of the United States. The highest-risk areas are often not deep in the woods but along the edges of daily life: where lawns meet brush, where pets walk through tall grass, where children play near leaf piles, and where hikers brush against vegetation along trails.
Lyme disease is expanding into states where it was once considered rare. Ohio, Indiana, Illinois, and Michigan are all showing measurable increases in tick activity and Lyme disease cases, according to MedicalDaily's prior coverage of the 2026 tick season. Residents of newly endemic counties in those states may not recognize tick exposure as a health concern — and their doctors may not automatically order Lyme disease testing.
States with traditionally high Lyme disease burden — Connecticut, New York, New Jersey, Pennsylvania, Massachusetts, Maryland, Virginia, Wisconsin, and Minnesota — remain the core endemic zone. But the boundaries of that zone continue to expand southward and westward.
What Doctors and Experts Say
Dr. Alison Hinckley, PhD, epidemiologist and Lyme disease expert with the CDC's Division of Vector-Borne Diseases, said tick season has arrived, and these small insects can cause serious illness. She noted that people have effective options — EPA-registered insect repellent, permethrin-treated clothing, tick checks after outdoor time, and removing attached ticks as quickly as possible.
Dr. Jonathan Jennings, MD, a board-certified internist with Medical Offices of Manhattan, told Healthline that rising temperatures have contributed to shorter and milder winters, allowing ticks and the animals they depend on to flourish. He said that since tick activity has increased, the risk of Lyme disease and other tick-borne diseases increases proportionally.
Dr. Robert Glatter, an emergency medicine physician, also told Healthline that emergency departments in endemic areas should be prepared for a corresponding rise in patients presenting with early Lyme disease and other tick-borne infections during peak season, from May through August.
What the Evidence Shows and What It Does Not
The 25 percent increase in April ER visits is a surveillance signal — a real and statistically meaningful change captured by the CDC's National Syndromic Surveillance Program. It does not by itself prove that Lyme disease case totals will rise proportionally in 2026. It is an early indicator, not a final case count.
MedicalDaily Evidence Check
- Data source: CDC National Syndromic Surveillance Program / Tick Bite Tracker
- Finding: Greater than 25% increase in ER visits for tick bites, April 2026 vs. April 2025
- Briefing source: Johns Hopkins Bloomberg School of Public Health, May 5, 2026
- Context: Highest April ER visit rate since 2017 in all regions except South Central U.S.
- What it proves: Increased tick-human contact and a likely early signal of an elevated tick-borne disease season
- What it does not prove: Final 2026 Lyme disease case totals will be a specific percentage higher than prior years
- What readers should know: Take prevention seriously now; do not wait for a diagnosis to act
Who Faces the Greatest Risk?
People most at risk for Lyme disease in 2026 include outdoor workers in landscaping, forestry, agriculture, and construction; hikers, campers, hunters, and people who spend time in wooded or grassy areas; children between 5 and 15 years old, who show consistently higher case rates in national surveillance; adults between 45 and 55; and residents of newly endemic counties in Ohio, Indiana, Illinois, and Michigan who may not recognize tick exposure as a health concern.
Pet owners also face elevated risk. Dogs that roam outdoors bring ticks into the home, potentially exposing family members who never enter the woods. The Companion Animal Parasite Council has issued elevated tick risk forecasts for 2026 across most of the United States.
Symptoms and Warning Signs to Watch For
Not all Lyme disease infections produce the classic bull's-eye rash. Studies suggest the rash is absent in a meaningful proportion of cases — meaning its absence does not rule out infection.
Early Lyme disease, appearing days to weeks after a bite, may include a round or oval expanding rash (with or without a central clearing), fatigue, fever and chills, headache, muscle and joint aches, and swollen lymph nodes.
Later-stage Lyme disease, appearing weeks to months after untreated infection, can cause severe joint pain and swelling (especially in the knee), facial drooping or Bell's palsy, irregular heartbeat, episodes of dizziness or shortness of breath, inflammation of the brain and spinal cord, and nerve pain or numbness in the hands or feet.
If you develop a rash or fever in the days to weeks after a tick bite, or after spending time in an area with ticks, seek medical care promptly, the CDC advises. Removing attached ticks within 24 hours can help prevent Lyme disease. Do not wait for a rash that may not appear.
What You Can Do Now
- Use an EPA-registered insect repellent containing DEET (20 to 30 percent), picaridin, or IR3535 when outdoors in grassy, brushy, or wooded areas. Find options at the EPA's repellent search tool .
- Apply permethrin to clothing, shoes, and gear — or purchase pre-treated clothing.
- Shower within two hours of coming indoors from outdoor activities to wash away unattached ticks.
- Perform a full-body tick check on yourself, your children, and your pets after all outdoor time.
- If you find an attached tick, remove it as soon as possible with fine-tipped tweezers . The CDC advises against waiting to go to the ER just for tick removal.
- Contact a health-care provider if you develop fever, rash, or flu-like symptoms within days to weeks of a known or suspected tick exposure.
- Tell your doctor about the tick exposure. Do not assume they will consider it without being told.
Cost and Access: What Patients Should Know
Early Lyme disease is treated with oral antibiotics — typically doxycycline for adults and amoxicillin or cefuroxime for children and pregnant people. A standard course runs 10 to 21 days. Generic doxycycline is widely available and typically costs under $20 at most pharmacies.
Lyme disease testing — the CDC-recommended two-tier blood test — is available through primary care doctors, urgent care centers, and many health department clinics. For uninsured patients, federally qualified health centers offer sliding-scale fees at findahealthcenter.hrsa.gov.
One access barrier worth noting: Lyme disease is still sometimes under-recognized in expanding-risk states. If your provider dismisses symptoms consistent with Lyme disease following a tick bite, requesting a referral to an infectious disease specialist is a reasonable step.
What Happens Next
Updated CDC case count data for 2024 are expected to be published later in 2026 and may confirm the geographic expansion already visible in tick surveillance data. Lyme disease vaccine research continues — a Phase 3 clinical trial showed 74 percent efficacy in a new candidate — though no human Lyme disease vaccine is currently approved in the United States. The 2026 tick season is expected to remain active through October in most endemic regions. MedicalDaily will report on new case data, vaccine developments, and any significant changes in CDC tick surveillance data as they become available.
The Bottom Line
Tick bite emergency room visits are up 25 percent, and tick populations are elevated across most of the United States. Peak season is here. Early Lyme disease responds well to standard antibiotics. Late-stage disease does not. The difference between those two outcomes often comes down to whether a tick bite is recognized, tested for promptly, and treated early. Prevention is straightforward and inexpensive. Do not wait for the rash that may not come before seeking evaluation after a tick bite during peak season.
