‘Stomach flu’ outbreak slams hikers on California section of Pacific Crest Trail

Dozens of hikers have fallen ill while on California section of the 2,650-mile Pacific Crest Trail, authorities said.

The trail runs from Canada to Mexico through Washington, Oregon and California.

The Pacific Crest Trail Association said in an Instagram post that it is aware of a “gastrointestinal illness in the Wrightwood area” in San Bernardino County.

A Reddit post said there have been dozens of cases and seven to 12 confirmed norovirus cases.

Noroviruses are highly contagious viruses that can cause vomiting and diarrhea.

The illnesses were first reported in early May, SF Gate reported.

“I’ve never been that weak,” hiker Ron Halls told the publication.

What to know about ‘stomach flu’ or noroviruses

Noroviruses, sometimes called “stomach flu,” cause vomiting, diarrhea and stomach cramps, according to the California Department of Public Health.

Every year, there are about 2,500 reported norovirus outbreaks across the country, with surges most common from November to April.

On average each year, the highly contagious viruses cause 109,000 hospitalizations, 465,000 emergency department visits and 19 million to 21 million illnesses, according to the U.S. Centers for Disease Control and Prevention.

Norovirus spreads easily from person to person, while infected individuals are experiencing symptoms, according to the California Department of Public Health.

Symptoms typically last one to three days, though someone can still be contagious up to two days after they feel better, according to the public health department’s website.

Good hygiene is key to avoiding noroviruses, WebMD.com suggests. Wash your hands frequently with soap and water, particularly after using the bathroom and before preparing food. Alcohol-based cleaners, such as hand sanitizers, are not as effective.

The site also advises carefully throwing away contaminated items, such as dirty diapers.

Wash raw fruits and vegetables, and cook oysters and other shellfish. Clean and disinfect surfaces with a mixture of detergent and chlorine bleach after someone’s sick, WebMD says.

And if you catch a norovirus, don’t prepare food for at least two to three days after you feel better.

What to know about the Pacific Crest Trail

The trail is a National Scenic Trail, the Pacific Crest Trail Association said.

“It reveals the beauty of the desert, unfolds the glaciated expanses of the Sierra Nevada, travels deep forests, and provides commanding vistas of volcanic peaks in the Cascade Range,” the association said.

Thousands of hikers trek along the trail each year, some for only a few miles and others on a monthslong journey along the entire trail.

The Pacific Crest Trail was featured in the book and movie “Wild.”

This story was originally published May 24, 2026 at 2:05 PM with the headline "‘Stomach flu’ outbreak slams hikers on California section of Pacific Crest Trail."