Spike in Leptospirosis Cases Among Bay Area Dogs Raises Concerns in Southern California

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Veterinarians are sounding the alarm about a spike in leptospirosis, a highly contagious bacterial disease, among dogs in the Bay Area. Clinicians and pet owners in Southern California are now wary of a possible outbreak, especially since the same illness sickened and killed many animals in the region a few years ago.

Why it matters

Leptospirosis can lead to a range of serious symptoms in dogs, including organ damage, and in rare cases, can also spread to humans. The disease is typically spread through contact with contaminated water or soil, raising concerns about potential outbreaks in areas with homeless encampments or other sources of standing water.

The details

Leptospira, the bacteria that causes leptospirosis, is found in wet soil and standing water. Dogs can be exposed at dog parks, day care, or while hiking. The Bay Area outbreak is also involving homeless encampments where the housed have companion dogs, a scenario that could potentially occur in Los Angeles as well.

• In 2001, there was a bad outbreak of leptospirosis in Southern California.
• From July 2021 through early 2022, there was a relatively smaller outbreak among dogs in LA County, with hundreds of dogs becoming sick and at least a dozen dying.

What they’re saying

What’s next

Veterinarians and public health officials in Southern California are closely monitoring the situation and urging pet owners to vaccinate their dogs and avoid contact with floodwater, standing water, or muddy run-off to prevent the spread of leptospirosis.