Tijuana’s municipal health department has begun a citywide operation to hunt down, capture, and kill dogs found running loose on the streets in an effort to stem an outbreak of illnesses caused by the tick-borne bacterium Rickettsia.

“If you have a dog, guard it carefully and make sure it doesn’t go into the street because after Monday, May 18, the Municipal Health Department will implement an intense operation to capture street dogs as part of the preventive measures being taken against Rickettsia in the city,” warned the Tijuana daily Frontera.

In Mexicali, where the outbreak began, 1600 dogs have already been captured and put to death, according to the Baja California secretary of health.

By late April, 9 of 14 people infected with a mysterious disease had died in three of Mexicali’s poorest neighborhoods. Health authorities now say they believe the illnesses may have been caused by Rickettsia, but only nine cases have been confirmed by blood tests.

On May 12, health officials announced the first confirmed case in Tijuana — a boy who lives in the Francisco Villa neighborhood. According to various news reports, the child was infected by a tick bite but is recovering from his illness.

Normally, owners have 72 hours to claim their pets in the city’s dog pound, but Tijuana health officials are recommending that dogs captured in the street be immediately euthanized. Officials have also ordered the fumigation of public schools. Health authorities recommend that anyone experiencing headache, high fever, and general malaise should go immediately to one of the six special centers set up across the city for evaluation.