Yosemite Valley, Yosemite National Park, California
Sin Nombre hantavirus HPS · Yosemite National Park, California · verified historical
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Summary
Long-term post-outbreak surveillance event rather than a clinical outbreak. Following the 2012 Curry Village hantavirus cluster, the California Department of Public Health and the National Park Service conducted 11 rodent-trapping campaigns in Yosemite Valley and 6 in Tuolumne Meadows between May 2013 and October 2018, plus more than 300 building evaluations to support rodent exclusion. Deer-mouse trap success and Sin Nombre orthohantavirus seroprevalence remained below 2012 levels, and no further laboratory-confirmed visitor cases of HPS attributable to Yosemite exposure were identified during this surveillance period.
Why this matters
Demonstrated that aggressive rodent exclusion and remediation in developed areas of Yosemite Valley sustained reductions in deer mouse abundance and SNV seroprevalence and prevented further visitor HPS clusters in the years immediately following the 2012 outbreak.
Sources
- T1 Long-Term Rodent Surveillance after Outbreak of Hantavirus Infection, Yosemite National Park, California, USA, 2012 Emerging Infectious Diseases (CDC) · 2026-05-07
- T1 Hantavirus in Yosemite U.S. National Park Service · 2026-05-07