An overview of the Harrison Street encampment in Berkeley, where leptospirosis has been discovered.
BERKELEY, Calif. - Berkeley city leadership issued a public health warning on Monday after animals in a homeless encampment tested positive for leptospirosis, a bacterial disease that can be fatal in dogs and humans.
City staff discovered the disease was present after testing animals in the vicinity of a homeless encampment on Harrison Street. Berkeley’s Public Health Officer recommended that encampment residents move out of the area as soon as possible, and relocate to at least a third of a mile away due to public health risk caused by the rat infestation transmitting the disease.
"The absence of confirmed human cases is reassuring but does not remove the risk of undiagnosed cases or future cases," Noemi Doohan, Berkeley’s Public Health Officer said in a Jan. 6 court filing. "If a human case were confirmed, that would elevate the urgency of the recommended response to protect human life and other animal life in the city of Berkeley."
The city advises dog owners to vaccinate their pets against leptospirosis, and the wrote the owners of "free roaming cats" should consider the same.
Signs of pet illness may include "excessive thirst, vomiting, shivering, and lethargy, and can progress to liver failure if untreated. Lepto can also be fatal to dogs."
In humans, leptospirosis can cause sudden high fever, throbbing headache, severe calf/leg pain, and red eyes (conjunctivitis), the court documents state. Without treatment the disease can cause kidney damage, meningitis, liver failure, trouble breathing, and even death.
The disease may not be immediately recognizable by doctors either, as it is usually associated with tropical conditions.
Problem area
Rats and their urine are a common vector for the disease.
"Current Harrison Street encampment conditions (tents, refuse, uncontained foods, RVs, standing water) prevent standard vector control teams from accessing and destroying rat nesting sites," the city alert states. "Rodent eradication, ongoing rat testing for leptospirosis, and remediation of the area to prevent a growing rat infestation is a medical and public health safety necessity that cannot be successfully completed while the encampment is occupied by temporary dwellings, people and dogs."
In addition to pushing for Harrison Street residents to relocate, the city is also encouraging residents to take precautions by avoiding touching the water in Codornices Creek or walking or biking through standing water in the area.
The creek has not been tested for leptospirosis, but noted that the presence of the disease so close to the creek means there is a significant risk of the disease spreading to the creek and wildlife if the infected rodent population is not brought under control.
Veterinarians treating sick dogs at the Harrison Street encampment first identified the disease in November, and Alameda County Vector Control confirmed the presence of leptospirosis by trapping and testing rats.
"This was of particular concern because testing of rats trapped at encampment over the last five years… had never previously produced any findings of leptospirosis in rats," the city’s health advisory states.
What's next
Berkeley city staff have launched an ongoing public health investigation into the disease’s spread in the encampment and the nearby community.
Cleanup will take at least 30 days — the length of time leptospirosis can live in soil — and the eradication of rats requires "many cycles of baiting the rats with poison in their underground burrows, removing the carcasses, and rebaiting over time," the advisory states.
The city is barred by a federal injunction from clearing the Harrison Street encampment, which has blocked the city from "implementing fully effective eradication efforts," in stopping the spread of the disease.