Outbreak of Acute Gastroenteritis Among Rafters and Backpackers in the Backcountry of Grand Canyon National Park, April–June 2022

A significant outbreak of acute gastroenteritis, primarily caused by norovirus, affected 222 backcountry visitors—including rafters and backpackers—in Grand Canyon National Park between April and June 2022. The highly transmissible nature of the virus, particularly in settings with close contact and limited hygiene access, was confirmed through testing of portable toilet specimens from nine rafting groups. Public health agencies recommended enhanced infection prevention measures, such as regular disinfection of water spigots, promotion of handwashing, and separation of ill individuals to mitigate future outbreaks. The study underscores the need for rapid illness reporting, adherence to IPC guidelines by commercial outfitters, and minimizing interactions among groups to prevent such incidents in protected backcountry environments.

Dale, A. P., Miko, S., Calderwood, L. E., King, R. F., Maurer, M., Dyer, L., Gebhardt, M., Maurer, W., Crosby, S., Wikswo, M. E., Said, M. A., & Mirza, S. A. (2022). Outbreak of Acute Gastroenteritis Among Rafters and Backpackers in the Backcountry of Grand Canyon National Park, April–June 2022. MMWR. Morbidity and Mortality Weekly Report, 71(38), 1207–1211. https://doi.org/10.15585/mmwr.mm7138a2