Norovirus outbreak hits Pacific Crest Trail

Pacific Crest Trail hikers near Wrightwood, California, have been reporting gastrointestinal illness in what trail groups and media reports describe as a suspected norovirus outbreak along a Southern California stretch of the route. The Pacific Crest Trail Association said it was aware of reports of illness in the Wrightwood area and was working with the San Bernardino County Department of Public Health as the situation was assessed. The Inertia reported on May 21 that at least two dozen hikers had symptoms consistent with norovirus and seven had been diagnosed. One 73-year-old hiker was evacuated by helicopter to a hospital in Lancaster and diagnosed there, according to that report. ### Where on the trail are hikers getting sick? Wrightwood, a trail town in the San Gabriel Mountains north of Los Angeles, has been the center of the reported illnesses. The Inertia, citing earlier reporting by SFGATE, said the outbreak appeared to be centered around Swarthout Valley, between Cajon Pass and Mount Baden-Powell, where hikers often rely on volunteer-supported water caches. (theinertia.com) A shared water cache in Swarthout Valley has emerged as one possible link among sick hikers, but the source has not been confirmed. The Inertia reported that one local volunteer said the contamination point could have been farther south because norovirus typically has an incubation period of about 48 hours. ### What do officials and the trail association say so far? (theinertia.com) The Pacific Crest Trail Association said in a statement that it was “aware of reports of gastrointestinal illness in the Wrightwood area” and was working with San Bernardino County public health officials. The group said it planned to share information publicly when it became available. San Bernardino County’s Department of Public Health has public guidance on norovirus and says suspected outbreaks of acute gastroenteritis must be reported immediately to local health authorities in California. (theinertia.com) California does not require reporting of every individual norovirus case, which can make early outbreak counts harder to pin down. ### Why is norovirus a particular problem on a long trail? (theinertia.com) Norovirus spreads through contaminated food or water, person-to-person contact, and contaminated surfaces, according to the Centers for Disease Control and Prevention and California health authorities. The PCTA says gastrointestinal illness can become a wilderness medical emergency and notes that shared surfaces and containers — including water-cache containers — can become sources of spread. (cdph.ca.gov) The Pacific Crest Trail Association says most water filters do not remove viruses. Its guidance tells hikers to boil or chemically treat water if they are worried about norovirus, avoid sharing food or bottles, and stay away from others for two days after symptoms stop. The group also says alcohol-based hand sanitizer may be ineffective against norovirus. ### How large does the outbreak appear to be? (theinertia.com) The Inertia reported at least two dozen hikers with symptoms and seven diagnosed cases as of May 21. Other follow-on reports described the number of sick hikers as “dozens,” but county officials had not publicly confirmed a larger cluster in the material reviewed here. A 73-year-old hiker’s evacuation underscored the severity of some cases. (pcta.org) The hiker told reporters he had been extremely weak from the illness, and media reports said lodging in Wrightwood that usually hosts Pacific Crest Trail hikers had temporarily closed while the situation was brought under control. Trail volunteers also replaced a communal water fill station with sealed bottled water, according to The Inertia. (theinertia.com) ### What should hikers watch for next? The Pacific Crest Trail Association has directed hikers to report the date and location of illnesses to local health departments and to file a U.S. Forest Service Pacific Crest Trail incident report. The association’s trail-conditions and safety pages are the main public channels likely to carry updates as San Bernardino County public health officials continue their assessment. (pcta.org) (theinertia.com)