CDC: More than 20 hikers contracted norovirus on Pacific Crest Trail in 2022

Today in Morbidity and Mortality Weekly Report Authors publish reports of at least 27 cases of acute gastroenteritis (AGE) among Pacific Crest Trail hikers in August and September 2022, suggesting a possible norovirus outbreak on hikes that share toilets and huts The person is sick.

Social media is awash with 2022 Washington hikers, although only 27 hikers responded to a September 2022 REDCap survey posted on the Washington Pacific Crest Trail Hiker Favorite Facebook group and reported illness. A large number of AGE accounts in .

Investigators collected symptoms, location and contact information from survey responses from 27 sick Pacific Crest Trail hikers. Twenty (74%) respondents reported short-term illness (median duration 2.5 days), and 17 (22%) reported vomiting and diarrhea.

“Twenty-one (95%) survey respondents who reported onset date indicated that they became ill within 73 miles of the Pacific Crest Trail in Washington; suggesting the possibility of environmental exposure,” the authors wrote.

The difficult environment of controlling norovirus

Environmental sampling of two toilets, a cabin and a water station in October showed no E. coli or norovirus contamination, but “…epidemiological links all support the conclusion that the outbreak was primarily caused by norovirus , and exposure to contaminated surfaces indoors in cabins and VIP toilets may amplify transmission.”

The hiking environment is a difficult environment for norovirus to control, the authors said, noting the lack of easily accessible clean water and soap for handwashing. Alcohol-based hand sanitizer, although common at campgrounds, is not effective against norovirus.