Skip to content

New Hampshire

Lone Star ticks in Merrimack County

CDC county record, 2025

Yes. Lone Star ticks are established in Merrimack County.

CDC counts a county as established when 6 or more Lone Star ticks, or more than one life stage, are found there in a year. They live in wooded edges, tall grass, brush and leaf litter, so people and pets who spend time outdoors here should expect to meet them in the warmer months. CDC county data, 2025 (opens in a new tab)

Peak season
April – AugustNo state figure; regional source: University of Rhode Island TickEncounter (opens in a new tab)
What to do
Use repellent outdoors and check yourself, your kids and your pets for ticks when you come in.
All of New Hampshire
SpreadingCDC lists 1 of New Hampshire's 10 counties as established and 1 more as reported.Ticks in New Hampshire

Loading counties…

Fig. 1. Merrimack County, outlined in ink, among New Hampshire’s 10 counties, by CDC’s 2025 record.
  • Established1
  • Reported1
  • No records8

If you find one on you

Take it out with fine-tipped tweezers, pulling straight up, and write down the date. The step-by-step guide tells you what to watch for, and for how long.

How to avoid bites in Merrimack County

  • Use EPA-registered repellent (DEET, picaridin, or oil of lemon eucalyptus)
  • Treat clothing and gear with permethrin
  • Wear long sleeves and tuck pants into socks in brushy areas
  • Stay on cleared trails and avoid tall grass and leaf litter
  • Shower within two hours of coming indoors
  • Do daily tick checks on people and pets during the season
The full prevention guide

Common questions

Are there Lone Star ticks in Merrimack County, New Hampshire?

CDC's 2025 county record for Merrimack County says "Established". CDC counts a county as established when 6 or more Lone Star ticks, or more than one life stage, are found there in a year. Ticks are most active from April to August. Finding ticks is not the same as personal disease risk.

When is tick season in Merrimack County?

In New Hampshire, Lone Star ticks are most active from April to August. They can still bite on warm days outside those months, so keep up tick checks.

Can a tick bite in Merrimack County cause alpha-gal syndrome?

It can. Lone Star tick bites are linked to alpha-gal syndrome, a delayed allergy to red meat. Most bites do not cause it, and only a doctor can diagnose it. Watch for hives, swelling or stomach trouble 2 to 6 hours after eating red meat.

What should I do if I find a tick in Merrimack County?

Remove it with fine-tipped tweezers, pulling straight up with steady pressure, then clean the area. Save a photo, note the date, and watch for symptoms over the following weeks. Contact a licensed clinician if a rash, fever, fatigue, or a delayed reaction to red meat develops.

How do I report or identify a tick found in Merrimack County?

Save the tick in a sealed bag with a moist paper towel and take a clear photo. Your New Hampshire health department or a university extension program may identify or test it. LoneStarMap does not collect tick reports. Official surveillance runs through those agencies.

Where this comes from8 sourcesShow
  1. 1.
    Where Ticks Live (opens in a new tab) · CDC

    The Lone Star tick is widely distributed in the Northeast, South, and Midwest U.S.

  2. 2.
    Lone Star Tick Surveillance (opens in a new tab) · CDC

    County-level established vs. reported records. 'Established' = 6+ ticks or multiple life stages collected in 12 months.

  3. 3.
    Alpha-gal Syndrome (opens in a new tab) · CDC

    What alpha-gal syndrome is, symptoms, and its association with tick bites.

  4. 4.
    Current and Future Distribution of the Lone Star Tick in North America (opens in a new tab) · Raghavan et al., PLOS ONE (2019)

    Ecological niche modeling of Amblyomma americanum range and projected northward expansion.

  5. 5.
  6. 6.
    Find the Repellent That Is Right for You (opens in a new tab) · EPA

    Search tool for EPA-registered repellents (DEET, picaridin, oil of lemon eucalyptus).

  7. 7.
    Lone Star Tick Surveillance Map Data, 2025 (county status) (opens in a new tab) · CDC

    Every county's status: Established (6 or more ticks, or more than one life stage, found in a year), Reported (fewer), or No records. Linked from CDC's Lone Star Tick Surveillance page.

  8. 8.
    Lone Star Tick (opens in a new tab) · University of Rhode Island TickEncounter

    Adults are active April to late August. Larvae typically latch on by the hundreds. Rhode Island reports have mostly been confined to Prudence Island.

Regional data last reviewed:

Educational information only, not medical advice. If someone is struggling to breathe or having a severe reaction, call 911. Read the disclaimer.