Berkeley Reports First Human Cases of Leptospirosis in Over a Decade

Months after Berkeley alerted its residents about the discovery of rats carrying leptospirosis near a homeless encampment in the Harrison Street area, officials have confirmed the city’s first human cases in more than ten years, which includes a fatality.

A public health update issued on Wednesday detailed that a person passed away in May after contracting leptospirosis while living in a recreational vehicle infested with rodents. Another individual who resided with the deceased also became infected but managed to survive after a prolonged hospitalization. Unfortunately, the first individual died shortly after being admitted to the hospital. Reports indicate that both delayed seeking medical attention for weeks or even months after their illnesses began.

City officials characterized the fatality as an “extreme situation.” Vector control teams removed nearly 200 rats from the RV before it was ultimately towed and destroyed. This vehicle was located about a mile from the Harrison Street encampment, which has been central to Berkeley’s ongoing response to leptospirosis.

Dr. Peter Chin-Hong, an infectious disease expert at UC San Francisco, noted that the high number of rodents increases the risk of exposure to any infected animals.

“The more rats you have, the more urine you might have, which raises the possibility of at least one of them carrying the infection,” he remarked. “If there’s just one rat, it’s kind of like playing rat roulette.”

Following the reported death, Berkeley Public Health has released updated guidelines advising medical providers to consider leptospirosis when treating patients who have been in contact with rats and present relevant symptoms.

Chin-Hong pointed out that this recent case highlights a paradox associated with leptospirosis: while it can be dangerous if overlooked, it is typically manageable when identified early on.

“Nobody should die from lepto,” Chin-Hong stated. “It’s a bacteria, and it’s treatable with antibiotics that all hospitals can provide.”

However, he acknowledged that many healthcare providers seldom see the disease, and patients frequently don’t seek help until it’s too late.

“Often, it gets misdiagnosed because it’s not common in the Bay Area,” he explained. “You really need to consider it or suspect it in order to treat it correctly.”

Leptospirosis spreads through exposure to the urine of infected animals, especially rats. The bacteria can enter the body through various entry points like the eyes, nose, mouth, or even cuts in the skin. Early symptoms typically resemble flu-like conditions such as fever, chills, headaches, muscle aches, nausea, and vomiting, but it can escalate to severe illness affecting multiple organs.

“It’s really a two-part illness,” Chin-Hong mentioned. “The initial phase mimics flu-like symptoms.”

According to Berkeley’s clinical guidelines, symptoms can manifest anywhere from two to 30 days post-exposure, with most cases appearing within one to two weeks. While many infections tend to be mild, around 10% may progress to severe cases that could lead to organ failure.

The city’s update revealed that the human cases occurred outside the previously defined risk zones around the Harrison Street corridor. Officials have since moved away from those specific zones and are adopting a broader approach that targets living conditions promoting transmission, particularly areas with significant rat infestations.

Despite the concerning nature of this death, Chin-Hong emphasized that leptospirosis is still relatively rare and that the overall risk for most residents remains low.

“There’s no need for panic,” he reassured. “But it should serve as a wake-up call that this bacteria is in our midst.”