{"id":823604,"date":"2026-05-26T16:23:22","date_gmt":"2026-05-26T16:23:22","guid":{"rendered":"https:\/\/www.europesays.com\/us\/823604\/"},"modified":"2026-05-26T16:23:22","modified_gmt":"2026-05-26T16:23:22","slug":"dog-daycare-leptospirosis-outbreak-in-los-angeles-highlights-vaccination-gaps-and-public-health-risks","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/us\/823604\/","title":{"rendered":"Dog Daycare Leptospirosis Outbreak in Los Angeles Highlights Vaccination Gaps and Public Health Risks"},"content":{"rendered":"

A 2021 outbreak of leptospirosis that sickened more than 200 dogs in Los Angeles County reveals critical gaps in vaccination practices and raises broader concerns about the spread of the disease between animals and people, according to new research<\/a> led by the University of California, Davis.\u00a0<\/p>\n

Leptospirosis is a bacterial disease that can cause severe illness in dogs, including acute kidney injury. In severe cases, dogs can die. Humans can also contract the disease through contact with contaminated animal urine (especially from rodents or livestock) or contaminated water. Human cases often result in flu-like symptoms that can be treated with antibiotics.<\/p>\n

In the new study, scientists traced the outbreak to dog daycare environments where close contact among animals could have accelerated dog-to-dog transmission, an atypical occurrence.\u00a0<\/p>\n

\u201cWe know that the boarding itself was a risk factor,\u201d said lead author Jane Sykes<\/a>, professor of small animal internal medicine at the UC Davis Weill School of Veterinary Medicine. \u201cIt might have been rodent problems in those facilities, or it might have just been really overcrowded facilities with lots of dogs in close contact with one another.\u201d<\/p>\n

The study<\/a> was published in Journal of Clinical Microbiology, an American Society for Microbiology journal.<\/p>\n

Daycare environments accelerated spread<\/strong><\/p>\n

During the peak of the outbreak, some veterinary clinics were seeing more than one case of leptospirosis a day coming from dogs that had recently been at dog daycare facilities in the westside of Los Angeles County.\u00a0<\/p>\n

\u201cThe outbreak was massive,\u201d Sykes said. \u201cIt might have been the biggest outbreak of leptospirosis in dogs that\u2019s ever been recognized.\u201d<\/p>\n

Video of leptospirosis growing in a specialized medium developed at the USDA-ARS National Animal Disease Center (NADC) in Ames, Iowa (Courtesy: Jarlath Nally, Animal Leptospirosis Research Laboratory at NADC)\u00a0<\/p>\n

Researchers analyzed 59 confirmed cases from two specialty veterinary centers and compared them with more than 15,000 control patients. The study confirmed the infections were caused by Leptospira interrogans serovar Canicola, one of the four strains the dog leptospirosis vaccine protects against.\u00a0 \u00a0<\/p>\n

While this strain is known to infect dogs, transmission typically occurs through contaminated environments, not direct contact between dogs. But conditions inside crowded daycare facilities after the COVID pandemic could have changed that dynamic.\u00a0<\/p>\n

Lack of vaccinations played key role<\/strong><\/p>\n

The findings underscore the importance of vaccinations and vigilance in settings where dogs congregate.<\/p>\n

\u201cAt the time, Los Angeles area veterinarians rarely offered leptospirosis vaccinations because the bacteria thrive in water from heavy rainfall and L.A. is an arid climate,\u201d Sykes said. \u201cIt was considered a low risk.\u201d<\/p>\n

As vaccination rates increased and some dog daycares temporarily closed, the outbreak subsided. Major veterinary organizations now recommend annual leptospirosis vaccination for all dogs.<\/p>\n

Leptospirosis is a bacterial disease that can cause severe illness in dogs, including acute kidney injury. These three doberman pinscher dogs were among other dogs at a homeless encampment in Oakland. Without vaccinations, they could be at risk of leptospirosis. (UC Davis)<\/p>\n

Disease not limited to Los Angeles<\/strong><\/p>\n

While the westside of Los Angeles outbreak was centered in high-end dog day care facilities, researchers are now investigating cases in homeless encampments in Berkeley and Oakland, where dogs, wildlife and environmental conditions are creating new pathways for transmission.<\/p>\n

\u201cThis disease \u2014 there\u2019s no boundaries for it,\u201d Sykes said. \u201cWe\u2019re talking about dogs with this disease owned by wealthy people in L.A. and dogs that are in homeless encampments on the streets of Berkeley dying with this disease because of rodent exposure.\u201d<\/p>\n

Early findings from investigations in the Bay Area show high infection rates in local rat populations. Rats are the most likely hosts for leptospirosis.\u00a0<\/p>\n

Public health implications<\/strong><\/p>\n

Dogs in encampments often roam between locations and may end up in shelters, increasing the risk of exposure to other animals and people. Although no human cases were linked in the Los Angeles outbreak, experts say the disease is likely underdiagnosed in people, and in recent years, leptospirosis has been recognized in people in large U.S. cities, albeit rarely.<\/p>\n

\u201cIt\u2019s probably the tip of the iceberg,\u201d Sykes said. \u201cThere are probably more unrecognized cases than we know about.\u201d\u00a0<\/p>\n

Leptospirosis is also expected to become more common as climate change brings more flooding.\u00a0<\/p>\n

Researchers emphasize that vaccination is the most effective way to protect dogs and reduce the risk of transmission to people.\u00a0<\/p>\n

\u201cThis is a really important One Health<\/a> problem,\u201d Sykes said. \u201cIt affects dogs and it affects people.\u201d<\/p>\n

Other UC Davis authors include Max W. Randolph and Krystle Reagan. No funding was received for this study.\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"A 2021 outbreak of leptospirosis that sickened more than 200 dogs in Los Angeles County reveals critical gaps…\n","protected":false},"author":3,"featured_media":823605,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_share_on_mastodon":"0"},"categories":[5123],"tags":[1582,276,4654,9619,2961,93001,224,5337,338447,2857],"class_list":["post-823604","post","type-post","status-publish","format-standard","has-post-thumbnail","category-los-angeles","tag-ca","tag-california","tag-dogs","tag-homeless","tag-la","tag-leptospirosis","tag-los-angeles","tag-losangeles","tag-uc-davis-weill-school-of-veterinary-medicine","tag-vaccines"],"share_on_mastodon":{"url":"","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/823604","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=823604"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/823604\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/823605"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=823604"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=823604"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=823604"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}