Tick-Borne Diseases: Lyme Disease, Symptoms, and Prevention

Ticks are more than a nuisance — they’re vectors for serious, potentially debilitating diseases. In the United States, tick-borne illnesses account for more than 50,000 reported cases per year (and many more unreported), with numbers rising as tick populations expand northward.

Understanding which tick species are in your area, how to prevent bites, and what to do after a tick bite can protect your family from significant illness.

Common Tick Species in the U.S.

Different tick species transmit different diseases. Knowing which tick bit you helps guide medical decisions.

Black-Legged Tick (Deer Tick) — Ixodes scapularis and I. pacificus

Range: Eastern U.S. (I. scapularis); Pacific Coast (I. pacificus) Diseases: Lyme disease, anaplasmosis, babesiosis, Powassan virus Description: Very small — adult female is about 1/8 inch, nymph is barely visible (poppy seed-sized). Dark reddish-brown. Red-orange body with dark scutum (shield).

The black-legged tick is the primary public health concern in the Northeast, mid-Atlantic, and upper Midwest.

American Dog Tick — Dermacentor variabilis

Range: Eastern U.S. and parts of the Pacific Coast Diseases: Rocky Mountain spotted fever, tularemia Description: Larger than the deer tick — adult about 3/16 inch. Brown with silver-white markings.

Lone Star Tick — Amblyomma americanum

Range: Southeast, south-central, and increasingly the Midwest and Northeast Diseases: Ehrlichiosis, tularemia, STARI (Southern tick-associated rash illness), alpha-gal syndrome (red meat allergy) Description: Distinctive white dot (star) on the back of females. Reddish-brown, aggressive biter.

Rocky Mountain Wood Tick — Dermacentor andersoni

Range: Rocky Mountain region Diseases: Rocky Mountain spotted fever, tularemia, Colorado tick fever, tick paralysis

Gulf Coast Tick — Amblyomma maculatum

Range: Coastal areas of the Southeast and Atlantic Coast Diseases: Rickettsia parkeri rickettsiosis, spotted fever

Major Tick-Borne Diseases

Lyme Disease

Caused by: Borrelia burgdorferi bacteria Transmitted by: Black-legged tick (requires 36–48 hours of attachment for transmission) Geographic range: Highest risk in Northeast, mid-Atlantic, upper Midwest Reported cases: ~500,000 annually in the U.S. (CDC estimates)

Symptoms:

• Early localized (3–30 days after bite):

  • Erythema migrans (bull’s-eye rash) — appears at bite site in 70–80% of cases; expands over days and may exceed 12 inches in diameter
  • Fatigue, fever, headache, muscle and joint aches, swollen lymph nodes

• Early disseminated (weeks to months after bite if untreated):

  • Additional rashes on other areas of the body
  • Facial palsy (Bell’s palsy)
  • Severe joint pain (Lyme arthritis)
  • Heart palpitations (Lyme carditis)
  • Nerve pain

• Late stage (months to years if untreated):

  • Severe joint arthritis
  • Neurological issues (encephalopathy, memory problems, neuropathy)

Treatment: Antibiotics (doxycycline, amoxicillin, or cefuroxime). Most cases treated early resolve completely. Delayed treatment can lead to longer-lasting symptoms.

Note: “Post-treatment Lyme disease syndrome” (sometimes called chronic Lyme) describes persistent symptoms in some patients after treatment — this is a real and recognized phenomenon, though its causes and treatment are subjects of ongoing research.

Rocky Mountain Spotted Fever (RMSF)

Caused by: Rickettsia rickettsii bacteria Transmitted by: American dog tick, Rocky Mountain wood tick, brown dog tick Geographic range: Throughout the U.S., highest incidence in North Carolina, Oklahoma, Arkansas, Tennessee, Missouri

Symptoms (appear 2–14 days after bite):

• High fever, headache, fatigue, and muscle pain
• Rash: Typically appears 2–5 days after fever — small, flat pink spots that later become petechiae (small red or purple spots that don’t blanch when pressed). Often begins on wrists and ankles, spreading to trunk. Rash absent in up to 20% of early cases.

Severity: Can be rapidly fatal without treatment — one of the most severe tick-borne diseases in the U.S.

Treatment: Doxycycline. Must be started promptly — do not wait for lab confirmation if RMSF is clinically suspected.

Anaplasmosis

Caused by: Anaplasma phagocytophilum bacteria Transmitted by: Black-legged tick Geographic range: Northeast, upper Midwest

Symptoms: Fever, headache, chills, muscle aches, sometimes nausea and vomiting. Rash is uncommon.

Treatment: Doxycycline. Usually resolves quickly with appropriate antibiotic treatment.

Ehrlichiosis

Caused by: Ehrlichia species bacteria Transmitted by: Lone star tick (primary), black-legged tick Geographic range: Southeast, south-central U.S.

Symptoms: Similar to anaplasmosis — fever, headache, muscle aches, malaise. More likely than anaplasmosis to cause severe illness in immunocompromised individuals.

Treatment: Doxycycline.

Babesiosis

Caused by: Babesia microti parasite (a red blood cell parasite, similar to malaria) Transmitted by: Black-legged tick Geographic range: Northeast (especially New England islands), upper Midwest

Symptoms: Range from no symptoms to severe hemolytic anemia. Fever, chills, sweats, headache, fatigue, nausea. Severe cases primarily in asplenic, immunocompromised, or elderly patients.

Treatment: Atovaquone + azithromycin (mild to moderate); clindamycin + quinine (severe)

Alpha-Gal Syndrome

Caused by: Lone star tick saliva sensitizing the immune system to alpha-gal (a sugar molecule in red meat) Result: Allergic reaction (ranging from hives to anaphylaxis) after eating red meat (beef, pork, lamb, venison) Note: A growing concern, particularly in the Southeast. May persist indefinitely.

How to Remove a Tick Correctly

Proper tick removal reduces disease transmission risk.

1. Use fine-tipped tweezers — not your fingers, nail polish, petroleum jelly, or heat
2. Grasp the tick as close to the skin surface as possible
3. Pull upward with steady, even pressure — do not jerk or twist (can cause mouthparts to break off)
4. After removal, clean the bite area with alcohol or soap and water
5. Dispose of the tick: submerge in alcohol, place in a sealed bag, or flush down the toilet
6. Do NOT crush the tick with your fingers

Transmission time: Most tick-borne diseases require several hours of attachment before transmission occurs. Checking for ticks after outdoor activities and removing them promptly significantly reduces risk.

Tick Prevention Strategies

Personal Protection

• Wear long pants tucked into socks and long sleeves in tick habitat (wooded or grassy areas)
• Use DEET (20–30% concentration) or picaridin on exposed skin — most effective and long-lasting repellents
• Apply permethrin to clothing and gear — kills ticks on contact, lasts through multiple washes. Do not apply permethrin directly to skin.
• Stay on trails in wooded areas; avoid brushing against vegetation

Top repellent products:

• OFF! Deep Woods (25% DEET) — reliable, widely available
• Sawyer Premium Permethrin — for treating clothing; lasts 6 weeks/6 washes
• Sawyer Picaridin Insect Repellent — effective DEET alternative, less greasy feel

After Outdoor Activities

• Perform a full-body tick check immediately after returning from wooded or grassy areas. Check: hairline, ears, neck, armpits, behind knees, groin, and belly button
• Shower within 2 hours of being outdoors — reduces risk of tick attachment
• Tumble dry clothes on high heat for 10 minutes to kill any attached ticks

Protect Your Yard

• Create a 3-foot-wide wood chip or gravel barrier between lawn and wooded areas
• Keep grass mowed and eliminate leaf litter where ticks shelter
• Treat the yard perimeter with bifenthrin (e.g., Ortho Home Defense) or permethrin-based granules in early spring and summer
• Apply Damminix Tick Tubes (cardboard tubes with permethrin-treated cotton) in wooded yard areas — mice pick up the cotton for nesting and the permethrin kills ticks on the mice, reducing the reservoir

Protect Your Pets

Keep dogs and cats on year-round tick prevention products (see our guide on flea and tick prevention).

When to See a Doctor After a Tick Bite

See a doctor promptly if:

• You develop a rash (especially a bull’s-eye pattern) within 30 days of a tick bite
• You experience fever, headache, muscle aches, or fatigue within 30 days of tick exposure
• The tick was attached for more than 36 hours (particularly in Lyme-endemic areas)

In high-risk Lyme areas, a single dose of doxycycline given within 72 hours of a known deer tick bite lasting 36+ hours can prevent Lyme disease. Ask your doctor about prophylactic treatment if you’ve had a high-risk exposure.

Bottom Line

Ticks are a serious health risk in much of the U.S., and the diseases they carry range from manageable (with prompt treatment) to potentially fatal (especially RMSF). Personal protection — DEET repellent on skin, permethrin on clothing, and thorough tick checks after outdoor activity — dramatically reduces exposure risk. Year-round tick prevention for pets reduces the risk of ticks being brought indoors. If you develop a rash or fever after a possible tick exposure, see a doctor promptly — early treatment with antibiotics is highly effective for most tick-borne diseases.