Baja California has recorded 10 rickettsia deaths so far in 2026, with Ensenada accounting for half of them. State Health Secretary Adrián Medina Amarillas confirmed that five people died in Ensenada, three in Tijuana, and two in Mexicali. Close to 100 confirmed cases have been logged statewide, and roughly half are concentrated in Ensenada.
Outbreak Shifts From Mexicali to Coastal Cities
The geographic pattern marks a notable change. Rocky Mountain spotted fever, the most dangerous form of rickettsiosis in Baja California, was historically concentrated in Mexicali. A CDC-linked study published in February 2025 documented how the epidemic spread from Mexicali to Tijuana and then to Ensenada by 2018. That research found over 54% of surveyed dogs in Ensenada tested seropositive for spotted fever group rickettsiae.
Medina Amarillas said the five Ensenada deaths are unusual for this early in the year. Rickettsia cases typically peak during the hotter summer months. In the summer of 2025 alone, 10 people died of rickettsiosis in Ensenada, with 28 confirmed positives out of 135 studied cases.
10 Day Emergency Response in Ensenada
State health teams have been working in Ensenada for roughly 10 days alongside municipal authorities. The response focuses on areas lacking basic sanitation services, where garbage accumulation and large populations of stray dogs create ideal conditions for the brown dog tick (Rhipicephalus sanguineus) that carries Rickettsia rickettsii.
Medina Amarillas said patients detected early have responded well to treatment with doxycycline, the standard antibiotic. But delayed diagnosis remains the primary factor in deaths. Research from a 2022 outbreak in northern Mexico found that starting treatment within 24 hours of symptom onset was statistically associated with survival.
Symptoms include sudden high fever, severe headache, muscle pain, and a rash that may appear several days after fever onset. Health officials urge anyone with these symptoms to seek medical care immediately rather than self-treating at home. Ensenada, a port city of roughly 540,000 people located about 80 miles south of the U.S. border on Highway 1, is home to a sizable foreign resident community in neighborhoods like El Sauzal, Chapultepec, and the downtown centro histórico.
Medina Amarillas noted that Mexicali has seen a decline in cases thanks to years of public awareness campaigns. State officials plan to replicate that community education model across Ensenada and Tijuana throughout 2026, according to El Imparcial.