Health authorities in Baja California are calling on residents to protect their homes and pets against rickettsia, a tick-borne disease that has killed 19 people in the state so far in 2025. The warning comes as warmer spring and summer temperatures create peak conditions for tick activity across the region.
Rickettsia, also known as Rocky Mountain spotted fever, is caused by bacteria transmitted through tick bites. The disease spreads through the circulatory system and can damage the skin, lungs, brain, and other organs. Baja California leads the country in reported cases, according to state Health Secretary Adrián Medina Amarillas.
What Residents Should Do at Home
State health officials recommend several steps to reduce tick exposure. Residents should clear yards of dry leaves, weeds, and accumulated debris where ticks thrive. Sealing cracks in walls and foundations can block ticks from entering the home.
Fumigation inside and outside the house is also essential. Since 2023, the state has sprayed more than 28,000 homes in high-risk areas. The eastern zone of Tijuana has been a primary target for these campaigns, as unpaved neighborhoods with overcrowded conditions face the highest risk.
Pets Are the Main Entry Point
Dogs and cats are among the most common ways ticks enter homes. Regular deworming and parasite treatment for pets is critical. Authorities have dewormed more than 13,000 pets in recent campaigns. Stray and roaming dogs pose a particular danger, as a CDC-linked study published in February 2025 found that dogs permitted to roam and the presence of roaming dogs in a neighborhood were strongly associated with tick infestations in both dogs and homes.
The Rocky Mountain spotted fever epidemic has spread across Baja California over the past 15 years, beginning in Mexicali before reaching Tijuana and then Ensenada by 2018. In that study, conducted in Ensenada, 54.6% of surveyed dogs tested positive for spotted fever group rickettsiae antibodies.
Symptoms and When to Seek Help
Rickettsia symptoms typically appear within one week of a tick bite. They include high fever, severe headache, fatigue, nausea, and muscle pain. Without treatment, the disease can become life-threatening. Health officials strongly discourage self-medication and urge anyone with symptoms to seek medical attention immediately. Treatment is most effective when administered within the first week of infection.
If you find a tick attached to your skin, use tweezers to grip as close to the skin as possible and pull straight out. Tick checks after spending time outdoors, especially in areas with tall grass or vegetation, are the single most important preventive step.
This story was first reported by Baja Times.