Rocky Mountain Spotted Fever in Mexico

Level 4 - Avoid All Travel
Level 3 - Reconsider Nonessential Travel
Level 2 - Practice Enhanced Precautions
Level 1 - Practice Usual Precautions

Key points 

  • Illness and death due to Rocky Mountain spotted fever (RMSF) have been reported in the northern region of Mexico along the U.S. border, particularly in Baja California, Sonora, Chihuahua, Coahuila, and Nuevo León.
  • RMSF has been found in several cities in northern Mexico, including
    • Tecate, Tijuana, Ensenada, and Mexicali in Baja California
    • Hermosillo in Sonora
    • Ciudad Juarez and Chihuahua City in Chihuahua
  • Ticks spread the bacteria that cause RMSF. The type of ticks that spread RMSF live on dogs and can be found anywhere that dogs live, including close to people’s homes and in their yards. RMSF is NOT spread from one person to another person.
  • You can protect yourself by:
    • Using Environmental Protection Agency (EPA)-registered insect repellant on exposed skin and clothing.
    • Checking your body, your child’s body, and clothing for ticks daily while traveling to the impacted areas.
      • If you find a tick on your body, remove it as soon as possible.
      • Ticks can be tiny and their bites may be painless, so you may not always notice a tick bite.
  • If traveling with your dog, you can protect yourself and your dog by using tick preventatives on your dog. Talk to your vet for further guidance.
  • RMSF can be deadly if not treated early. Seek medical attention immediately if you or a family member has traveled to northern Mexico and develop symptoms including: fever, headache, nausea, vomiting, abdominal pain, aches, rash, or swelling around the eyes or on the back of hands during travel or within 2 weeks of returning to the United States.

Traveler Information

Clinician Information

Map of northern Mexico
Map of northern Mexico (View larger)
What is RMSF?

Rocky Mountain Spotted Fever (RMSF) is a potentially deadly bacterial disease spread through the bite of an infected tick.  

RMSF is spread by the brown dog tick (Rhipicephalus sanguineus) (PDF) in parts of the southwestern United States and Mexico.

Symptoms of RMSF include fever, headache, and rash. The rash usually appears about 2–4 days after onset of symptoms. However, some patients never develop a rash. The disease can rapidly progress and be deadly if not treated early with the recommended antibiotic, doxycycline. Children younger than 10 years old are 5 times more likely than adults to die from RMSF.

Doxycycline is recommended for the treatment of RMSF in adults and children of all ages.