The 2012 Yosemite hantavirus outbreak was an outbreak of hantavirus infections linked to visits to Yosemite National Park in California, United States, during 2012.[1][2] The outbreak was unusual and represented a rare type of hantavirus outbreak, linked to rodent exposure in a specific type of housing.[3]
The outbreak resulted in nine confirmed cases of hantavirus pulmonary syndrome (HPS) in visitors to Curry Village, and in one who lived 15 miles away.[1] Three people died from the disease.[1] Following the discovery of the outbreak, the National Park Service closed and disinfected hundreds of tent cabins and notified thousands of visitors who may have been exposed.[7]
Health authorities from the Centers for Disease Control and Prevention and California investigated the outbreak. Officials determined that insulation in the tent cabin walls provided nesting spaces for infected rodents, increasing the risk of human exposure.[8]
Significance
At least until 2014, the 2012 hantavirus outbreak at Yosemite National Park was the largest recognised Sin Nombre virus outbreak in the U.S. since the 1993 Four Corners hantavirus outbreak, and included a case of HPS with an unusually long 49 days incubation period.[3][9][a]
The outbreak led to a marked increase in testing for Sin Nombre virus specific IgM by the National Reference Laboratory in 2012.[11][12] The additional data helped refine hantavirus antibody testing algorithms and improve specificity by raising the cutoff required for a positive result, thereby reducing false-positive results.[11][12]
The social significance of the 2012 Yosemite hantavirus outbreak included increased public awareness and fear of rodent-borne disease, disruption to tourism at Yosemite National Park, and improved public health communication, surveillance, and prevention measures for HPS.[13]
Timeline
2012
2 July: Onset of illness in an affected individual who had been staying at Curry Village since 3 June.[3]
16 August: California Department of Public Health report two confirmed cases of HPS in Californians who had resided in Yosemite National Park.[14]
21–22 August: 185 traps are placed around Curry Village.[3]
27 August:
US National Park Service report that in 2012 three visitors of Yosemite National Park had been diagnosed with HPS and a further visitor was suspected as having the illness.[1] All four visitors, two of whom died, had stayed at the Curry Village's signature tent cabins.[1]
Other visitors contacted and asked to seek medical attention if have symptoms.[1]
28 August: All 91 signature tent cabins at Yosemite are closed.[3]
30 August: US National Park Service report total confirmed cases reaches six.[1]
4–5 September: 89 traps placed in Tuolumne Meadows and 133 in Curry Village.[3]
1 November:
US National Park Service report total confirmed cases reaches 10, with three deaths.[1]
Nine of 10 cases reported to have stayed at signature tent cabins in Curry Village.[1]
2013
25 May: Hantavirus is detected in 14% of Curry Village's deer mice.[1]
↑Hantavirus surveillance in the U.S. commenced in 1993. From then to 2023, 890 cases were reported in the U.S.[10]
References
12345678910Conover, Michael R.; Vail, Rosanna M. (2015). "23. Hantaviruses". Human Diseases from Wildlife. Boca Ratan: CRC Press. p.380. ISBN978-1-4665-6214-1.
↑Danforth, Mary E.; Messenger, Sharon; Buttke, Danielle; Weinburke, Matthew; Carroll, George; Hacker, Gregory; Niemela, Michael; Andrews, Elizabeth S.; Jackson, Bryan T.; Kramer, Vicki; Novak, Mark (March 2020). "Long-Term Rodent Surveillance after Outbreak of Hantavirus Infection, Yosemite National Park, California, USA, 2012". Emerging Infectious Diseases. 26 (3): 560–567. doi:10.3201/eid2603.191307. ISSN1080-6059. PMC7045852. PMID32091360.
123456Núñez, Jonathan J.; Fritz, Curtis L.; Knust, Barbara; Buttke, Danielle; Enge, Barryett; Novak, Mark G.; Kramer, Vicki; Osadebe, Lynda; Messenger, Sharon; Albariño, César G.; Ströher, Ute; Niemela, Michael; Amman, Brian R.; Wong, David; Manning, Craig R.; Nichol, Stuart T.; Rollin, Pierre E.; Xia, Dongxiang; Watt, James P.; Vugia, Duc J. (March 2014). "Hantavirus infections among overnight visitors to Yosemite National Park, California, USA, 2012". Emerging Infectious Diseases. 20 (3): 386–393. doi:10.3201/eid2003.131581. ISSN1080-6059. PMC3944872. PMID24565589.
↑Hartline, James; Mierek, Chris; Knutson, Tristan; Kang, Christopher (June 1, 2013). "Hantavirus infection in North America: a clinical review". The American Journal of Emergency Medicine. 31 (6): 978–982. doi:10.1016/j.ajem.2013.02.001. ISSN0735-6757. PMID23680331.
↑"Hantavirus pulmonary syndrome – Yosemite National Park, United States of America". World Health Organization. September 4, 2012. Archived from the original on May 11, 2026. Retrieved May 9, 2026.
↑Krautkrämer, Ellen; Kruger, Detlev H.; Zeier, Martin (December 2, 2012). "Recent outbreaks of hantavirus disease in Germany and in the United States". Kidney International. 82 (12): 1243–1245. doi:10.1038/ki.2012.359. ISSN0085-2538. PMID23203017.
↑Vitek, Christopher R.; Breiman, Robert F. (2014). "Hantavirus Infections among Overnight Visitors to Yosemite National Park, California, USA, 2012". Emerging Infectious Diseases. 20 (3): 386–393. doi:10.3201/eid2003.131581. PMC3944872. PMID24565589. Retrieved May 9, 2026.
↑Vial, Pablo A.; Ferrés, Marcela; Vial, Cecilia; Klingström, Jonas; Ahlm, Clas; López, René; Le Corre, Nicole; Mertz, Gregory J. (September 2023). "Hantavirus in humans: a review of clinical aspects and management". The Lancet. Infectious Diseases. 23 (9): e371–e382. doi:10.1016/S1473-3099(23)00128-7. ISSN1474-4457. PMID37105214. Retrieved May 15, 2026.
↑"Reported Cases of Hantavirus Disease". www.cdc.gov. Centers for Disease Control and Prevention. May 8, 2026. Archived from the original on May 10, 2026. Retrieved May 10, 2026.
12Landry, Marie Louise (July 2016). "Immunoglobulin M for Acute Infection: True or False?". Clinical and Vaccine Immunology. 23 (7): 540–545. doi:10.1128/CVI.00211-16. ISSN1556-679X. PMC4933779. PMID27193039.
12Prince, Harry E.; Lieberman, Jay M. (August 2013). "Impact of the Yosemite Hantavirus Outbreak on Hantavirus Antibody Testing at a National Reference Laboratory". Clinical and Vaccine Immunology. 20 (8): 1213–1216. doi:10.1128/CVI.00326-13. PMC3754509. PMID23740929.
↑Bach, Michelle (2017). "Social Implications of the Yosemite Hantavirus Outbreak". Pathways: Stanford Journal of Public Health (SJPH). 6: 23–26. Archived from the original on May 10, 2026.
↑Osadebe, Lynda U. (November 16, 2012). "Notes from the Field: Hantavirus Pulmonary Syndrome in Visitors to a National Park — Yosemite Valley, California, 2012". Centers for Disease Control and Prevention. Archived from the original on May 10, 2026. Retrieved May 9, 2026.
