Norovirus Cases Reported Along Pacific Crest Trail in California

Several hikers reportedly sought treatment at medical facilities in Hesperia and Victorville and later reported being told they had norovirus.

Kelly McBride Ni

Published: 5/29/2026, 11:25:43 PM EDT

Norovirus Cases Reported Along Pacific Crest Trail in California — A couple hikes in the mountains close to Point Mugu as hiking paths reopen in Ventura County, Calif., on May 23, 2020. (Brent Stirton/Getty Images.)

Reports of norovirus among hikers on the Pacific Crest Trail in Southern California have raised concerns among trail communities as the highly contagious virus continues circulating across the United States.

The Pacific Crest Trail Association said in a public statement on May 21 that it is aware of "reports of gastrointestinal illness in the Wrightwood area," and is working with the San Bernardino County Department of Public Health as officials assess the situation.

Wrightwood is a mountain community northeast of Los Angeles. The Pacific Crest Trail is a 2,650-mile route stretching from the Mexican border in California to the Canadian border in Washington.

According to the U.S. Centers for Disease Control and Prevention (CDC), the norovirus causes an estimated 19 to 21 million illnesses each year, with about 2.27 million outpatient clinic visits, 465,000 emergency department visits, and 109,000 hospitalizations annually.

While most people recover without complications, the CDC estimates the virus contributes to about 900 deaths each year, primarily among adults age 65 and older.

During Aug. 1, 2025 to May 7, 2026, the CDC's NoroSTAT surveillance system recorded 1,194 outbreaks during the 2025-26 season. The CDC said that figure is within the middle range of outbreak activity reported over the past 13 seasons.

California, Ohio, and Wisconsin have the highest reported outbreaks in the U.S. from Sept. 1, 2025 to April 30, 2026.

Francis Delapaz, a spokesperson for the San Bernardino County Department of Public Health, told SFGATE that the department was aware of one reported case as of May 18 but did not have evidence of a confirmed increase or cluster of norovirus cases in the Wrightwood area beyond what would typically be expected.

Several hikers sought treatment at medical facilities in Hesperia and Victorville and later reported being told they had norovirus, according to SFGATE. At least one hiker was airlifted from the trail after becoming severely dehydrated, according to the outlet.

Norovirus spreads easily through contaminated food, water, surfaces, and close contact with infected people.

Trail known for Unexpected Acts of Generosity, Volunteers

Along the Pacific Crest Trail, hikers have a network of volunteer-supported food and water sources.

Many hikers rely on volunteers who often provide rides, meals, lodging, and other assistance referred to as “trail angels.” Hikers also encounter “trail magic,” a term for unexpected acts of generosity such as snacks, drinks or water left along the route. Various water sources and stations are mapped along the trail for hikers to refill their water.

In Southern California’s desert and mountain sections, hikers often depend on water caches maintained by volunteers because reliable streams and springs can be scarce, especially during warmer months.

Some hikers and volunteers told SFGATE that several illnesses may have been linked to a water cache in Swarthout Valley between Cajon Pass and Mount Baden-Powell, where ill hikers were seen filling their bottles with water.

According to SFGATE, volunteers later replaced shared containers with sealed water bottles and asked hikers to separate used bottles from clean supplies as a precaution. No public health agency has confirmed a source of the illnesses.

What is Norovirus?

According to the CDC, norovirus is a highly contagious virus that causes acute gastroenteritis, an inflammation of the stomach and intestines.

It is the leading cause of foodborne illness in the U.S. and can spread rapidly in settings where people share food, water, or living spaces.

Symptoms often develop 12 to 48 hours after exposure and most commonly include vomiting, diarrhea, nausea, and stomach pain.

Some people also experience fever, headache, and body aches. Most healthy adults recover within 1 to 3 days, although they can continue to spread the virus for several days after symptoms end.

The virus spreads through direct contact with an infected person, consuming contaminated food or water, or touching contaminated surfaces and then touching the mouth. Only a small number of virus particles can cause infection.

There is no specific antiviral treatment for norovirus, and antibiotics are ineffective because norovirus is a virus rather than a bacteria. The CDC recommends drinking plenty of fluids to prevent dehydration, as severe dehydration may require medical treatment and intravenous fluids.

Norovirus is also often associated with outbreaks on cruise ships, where large numbers of people live and eat in close quarters.

While cruise ship outbreaks account for about 90 percent of diarrheal disease outbreaks on cruise ships, the CDC notes, they account for only a small percentage of all reported norovirus outbreaks.

“Norovirus can persist on surfaces for days or weeks and is resistant to many common disinfectants,” says the CDC.

Most outbreaks occur in healthcare facilities, schools, restaurants, and other places where people gather.

Public health officials recommend frequent handwashing with soap and water, especially after using the restroom and before eating or preparing food.

Alcohol-based hand sanitizers may help reduce germs but are generally less effective against norovirus than proper handwashing.

Bleach-based products approved for norovirus control are recommended for cleaning contaminated surfaces.