A leptospirosis outbreak initially detected around a large homeless encampment in North Berkeley has led to one fatality and one hospitalization among individuals living in an RV approximately one mile from the site. These are the first known human cases of the disease in Berkeley in over a decade.
The patients, who resided together in an RV, reportedly fell ill but did not seek medical attention for weeks or potentially months, a delay believed to have contributed to the severity of their conditions. The surviving patient required a lengthy hospitalization before recovering, according to city officials. The cases were confirmed in May.
Spread and Risk Assessment
While the outbreak appears to have spread beyond the initial radius where public health officials advised precautions in January, the risk to housed residents of Berkeley is considered “extremely low.” This is because they are less likely to come into contact with infected rats, the primary vector for the bacteria. Individuals living in camps or RVs, or those with greater exposure to rats, face a higher danger.
The disease typically spreads through the urine of infected rats, which can contaminate standing water and infect other animals through consumption or absorption into open wounds. The two individuals known to have contracted leptospirosis were reportedly using their RV to trap, feed, and breed wild rats, according to a memo from City Manager Paul Buddenhagen. The city has not publicly identified the patients.
Public Health Recommendations and Mitigation Efforts
Public health officials are recommending that dog owners ensure their pets are up-to-date on leptospirosis vaccinations, as dogs are a common domesticated animal to contract the illness. Vaccines are available for dogs, cats, and many livestock animals.
For the general public, officials advise against attempting to exterminate rats independently. Instead, residents are directed to contact Alameda County Vector Control Services for assistance. County officials and contractors are actively working to eliminate infected rats.
Residents of camps and RVs are urged to store food and water in sealed containers, manage trash to prevent rat nesting, and avoid contact with rats or their excretions. Broader recommendations for infection prevention include washing produce from local gardens, wearing protective clothing, covering wounds, avoiding contaminated water, showering after potential exposure, cleaning wounds, not touching sick or dead animals, and consuming only clean drinking water.
The city has removed approximately 40 tons of trash from the Harrison Street encampment since February to help control rat populations. Testing of 14 dogs at the camp by UC Davis researchers yielded negative results, and owners were offered free vaccinations, though two dogs tested positive late last year. Berkeley public health workers have distributed protective gear, clothing, and educational materials about leptospirosis to individuals residing at the camp.
Mitchell Landsberg is the senior reporter for News Raise and focuses on Technology. Mitchell regularly writes about social media platforms and how influencers, industry and general people use them to communicate and make money.
