Two people living in a heavily contaminated RV near a homeless encampment in Berkeley, California, contracted leptospirosis, a potentially fatal disease associated with infected rat urine. One of them later died following a prolonged hospital stay.
The patients were staying in a rat-infested recreational vehicle roughly one mile from the encampment near Eighth and Harrison streets, where Berkeley officials eventually identified rats carrying the same disease.
“Both individuals had been living in a severely rat-infested RV about one mile from the Harrison Street encampment. Tragically, one of the patients died and one recovered after a lengthy hospitalization,” a city memo released in June stated.
Leptospirosis is a flu-like illness that can become life-threatening. People and animals may contract it after coming into contact with urine from infected animals, including rats.
Berkeley began removing the encampment Tuesday after a court authorized the city to dismantle its tents and other structures. Officials had classified the sprawling site as both a fire risk and a public nuisance, citing the leptospirosis outbreak and a serious rat problem.
The city first learned of a possible health threat in December 2025, when veterinarians treated dogs that had fallen ill.
Subsequent testing showed that rats living at the encampment were infected with leptospirosis. In response, Berkeley issued a public health alert and encouraged people to take precautions.
City officials urged pet owners to “ensure dogs have the leptospirosis vaccine” and said the encampments should be closed.
The cases involving the two RV residents add to the growing health and safety concerns surrounding the rat-infested Berkeley encampment as the city works to clear the area.
Efforts to carry out a complete cleanup had been delayed several times by court orders and lawsuits. Berkeley ultimately secured permission to proceed, but the city was required to help residents with disabilities find new accommodations.
Leptospirosis is relatively rare in Berkeley and is more commonly associated with warm, tropical settings such as Hawaii.
“Humans swim in the water, and then the bacteria that lives in the urine multiplies with warm weather and then gets into the cuts on the skin of humans or the eyes or dogs, too. That’s how people get sick,” an infectious disease specialist at UCSF told SFGATE.
About 1 million leptospirosis infections occur worldwide each year, resulting in approximately 60,000 deaths.