About LoneStarMap

Most people have never heard of alpha-gal syndrome, even where Lone Star ticks are common. People often find this site after a bite, when they are worried. So it puts the answer first, in plain words, and shows where each answer comes from.

Every state gets one of four levels. A level says where Lone Star ticks are found and, at the top level, where CDC has counted the most suspected alpha-gal cases. It is not your personal risk. A tick bite anywhere deserves the same care.

1. Rarely reported

   16 places

   Few or no Lone Star tick reports in public data. Other ticks still live here.

   What it rests on: CDC lists no county in the state where Lone Star ticks are established. At most a few counties have a report.

   Alaska, Arizona, California, Colorado, Hawaii, Idaho, Minnesota, Montana, Nevada, New Mexico, North Dakota, Oregon, Utah, Vermont, Washington, Wyoming

2. Spreading

   8 places

   Reports are increasing at the edge of the Lone Star tick's range.

   What it rests on: CDC lists the tick as established in a handful of counties at most (5 or fewer), often with reports from others nearby.

   Connecticut, Maine, Massachusetts, Michigan, New Hampshire, Rhode Island, South Dakota, Wisconsin

3. Found here

   14 places

   Inside the Lone Star tick's documented range.

   What it rests on: CDC lists Lone Star ticks as established in part or most of the state, inside the tick's documented range.

   Alabama, District of Columbia, Florida, Georgia, Iowa, Louisiana, Nebraska, New Jersey, New York, Ohio, Pennsylvania, South Carolina, Texas, West Virginia

4. Alpha-gal hotspot

   13 places

   Inside the range, and among the states where CDC found the highest rates of suspected alpha-gal cases.

   What it rests on: Found here, and one of the 13 states CDC's 2023 report names for the highest rates of suspected alpha-gal cases.

   Arkansas, Delaware, Illinois, Indiana, Kansas, Kentucky, Maryland, Mississippi, Missouri, North Carolina, Oklahoma, Tennessee, Virginia

The top and bottom levels follow fixed rules, and a test checks them against the data. “Alpha-gal hotspot” goes only to the 13 states named in CDC MMWR, 2023 (opens in a new tab). “Rarely reported” goes only to states where CDC lists no established county. Between “Spreading” and “Found here” there is no single cut-off number. We weigh CDC’s county counts with the state’s own sources, and each state page shows both.

Each county page opens with CDC’s own record for that county, from CDC county data, 2025 (opens in a new tab). CDC sorts every county into one of three groups:

• EstablishedCDC counts a county as established when 6 or more Lone Star ticks, or more than one life stage, are found there in a year.
• ReportedLone Star ticks have been found here, but fewer than CDC needs to call them established.
• No recordsNo Lone Star ticks from this county have been reported to CDC. That does not mean there are none.

We never invent a number for a county. Where CDC names a county for its alpha-gal cases, the page quotes CDC’s figures and links the report.

Each state’s peak months come from a named source. Where a state has its own figure, we use it. Where it does not, we use a neighbouring state’s figure or CDC’s national guide, and the page says which. See every state’s months and sources.

• Every fact on a page links to a source. The full list is on the sources page.
• We open each new source and find the sentence that supports the claim before it goes on a page.
• Medical facts come from CDC, state health departments, university extension programs and peer-reviewed research.
• Where public data is thin, the page says so instead of guessing.
• Reading pages show when they were last reviewed.

See every source.

• It does not give a personal risk score. Levels describe places, not people.
• It does not diagnose or treat anything. Only a clinician can diagnose alpha-gal syndrome or a tick-borne illness.
• It does not collect tick reports. Official surveillance runs through state health departments.
• The bite log stays on your device. It is never uploaded.

If something here is wrong or out of date, please tell us, with a link to the source if you have one. LoneStarMap is not medical advice. Read the disclaimer.