The Centers for Disease Control and Prevention (CDC) has issued a health advisory regarding an outbreak of Rocky Mountain spotted fever (RMSF) in Tecate, Baja California, Mexico. This alert is crucial for travelers and residents in and around Tecate, Mexico, as RMSF is a serious and potentially fatal illness if not treated promptly. This article provides essential information about the outbreak, symptoms, treatment, and preventative measures, ensuring you stay informed and safe when visiting Tecate, Mexico.
Understanding Rocky Mountain Spotted Fever (RMSF)
RMSF is a severe tick-borne disease caused by the bacteria Rickettsia rickettsii. It is transmitted to humans through the bite of infected ticks. While the name might suggest otherwise, RMSF is prevalent across North, Central, and South America, including northern Mexico. In these regions, the brown dog tick (Rhipicephalus sanguineus), commonly found on domestic dogs, is a primary vector, especially in urban and peri-urban settings like Tecate, Mexico.
From July to December 2023, health authorities identified five cases of RMSF in individuals who had recently traveled to Tecate, Mexico. These cases, reported in southern California hospitals, included both US and Mexican residents, with a concerning number being children under 18. Tragically, three of these five individuals succumbed to the illness, highlighting the severity and rapid progression of RMSF if left untreated.
RMSF is known for its rapid progression, and without timely treatment, it can be fatal within days. Early symptoms can be easily mistaken for other illnesses, making awareness and prompt medical attention critical.
Recognizing the Signs and Symptoms of RMSF
The initial symptoms of RMSF can be non-specific and may include:
- Fever (low to moderate)
- Headache
- Gastrointestinal issues
- Abdominal pain
- Muscle aches (myalgia)
- Swelling around the eyes and back of hands
A characteristic rash may appear 2-4 days after the onset of fever, typically starting on the wrists and ankles before spreading. Initially, the rash may be faint and macular (flat), but it can progress to petechial (small, pinpoint spots) around day 5 or 6. It’s important to note that not all patients develop a rash, and its absence should not rule out RMSF, especially in the early stages of illness.
As RMSF progresses, particularly after day 5, more severe symptoms can develop, including:
- Altered mental status
- Coma
- Cerebral edema
- Respiratory distress
- Necrosis (tissue damage)
- Multiorgan system failure
The disease can advance quickly, with approximately half of fatalities occurring within eight days of symptom onset. Untreated RMSF has a high fatality rate, especially in Mexico, where it can exceed 40%. Children under 10 are also at a significantly higher risk of fatal outcomes.
Diagnosis, Treatment, and the Importance of Early Action
Prompt diagnosis and treatment are crucial for surviving RMSF. If you experience these symptoms, especially after traveling to Tecate, Mexico, or other areas in northern Mexico known for RMSF, seek medical attention immediately and inform your healthcare provider about your travel history.
Diagnosis:
Healthcare providers should consider RMSF in patients presenting with fever, headache, and rash, particularly those with recent travel to Tecate, Mexico, or similar regions. Diagnostic testing, including PCR and serology, can confirm RMSF, but treatment should not be delayed pending test results.
Treatment:
Doxycycline is the recommended first-line treatment for RMSF for both adults and children, regardless of age. Early administration of doxycycline is life-saving. Even in cases of suspected RMSF, initiating doxycycline treatment immediately is vital and should not be postponed for lab confirmations.
Recommendations for Travelers to Tecate, Mexico
While visiting Tecate, Mexico, or other areas with RMSF risk, take these precautions to minimize your risk of tick bites and RMSF:
- Be Tick Aware: Understand that ticks are prevalent in outdoor and even urban areas in Tecate, Mexico.
- Use Repellent: Apply insect repellent containing DEET, picaridin, or other EPA-approved repellents on exposed skin and clothing.
- Treat Clothing and Gear: Use permethrin to treat clothing and gear, such as boots, pants, socks, and tents.
- Avoid Tick-Infested Areas: If possible, avoid wooded and bushy areas with high grass and leaf litter where ticks may be found.
- Walk in the Center of Trails: When hiking or walking outdoors, stay in the center of trails to avoid brushing against vegetation where ticks may be present.
- Check for Ticks Regularly: Conduct thorough tick checks on yourself, your children, and pets after spending time outdoors, especially in areas like Tecate, Mexico. Pay close attention to areas under the arms, in and around the ears, inside the belly button, back of the knees, in and around the hair, between the legs, and around the waist.
- Bathe or Shower Soon After Being Outdoors: Showering within two hours of coming indoors has been shown to reduce your risk of getting Lyme disease and may be effective in reducing the risk of other tick-borne diseases.
- Examine Gear and Pets: Check your clothing, gear, and pets for ticks after being outdoors. Ticks can come into your home on clothing and pets and then attach to you later.
If you develop symptoms of RMSF after returning from Tecate, Mexico, seek medical attention immediately and inform your healthcare provider about your travel to Tecate and possible tick exposure. Early diagnosis and treatment with doxycycline are critical to preventing severe illness and death from Rocky Mountain Spotted Fever.
Stay Informed and Stay Safe in Tecate, Mexico
This health advisory serves as a critical reminder of the potential health risks associated with travel to Tecate, Mexico, and other areas where RMSF is endemic. By staying informed about RMSF, recognizing the symptoms, and taking preventive measures, travelers can significantly reduce their risk and enjoy safer travels. Always prioritize your health and seek prompt medical attention if you suspect you may have contracted RMSF.
For more information about RMSF, please refer to the following resources from the CDC:
- Diagnosis and Management of Tickborne Rickettsial Diseases: Rocky Mountain Spotted Fever and Other Spotted Fever Group Rickettsioses, Ehrlichioses, and Anaplasmosis — United States
- RMSF Training Module: Clinical Diagnosis and Treatment for Healthcare Providers (Continuing Education) | Rocky Mountain Spotted Fever (RMSF) | CDC
- Health Department Directories – Public Health Professionals Gateway
- For Public Health Officials: Rocky Mountain Spotted Fever (RMSF) | CDC
