Stomach illness hits Colorado River rafters

Wednesday, June 19, 2002 | 11:37 a.m.

A wave of stomach illness has been spreading among rafters along the Colorado River, but it has not been felt at Lake Mead, local officials said.

Fifty-nine people on five separate rafting trips through the Grand Canyon developed nausea, diarrhea and vomiting, said Maureen Oltrogge, spokeswoman for the Grand Canyon National Park Service on Tuesday. No new cases have been reported since Friday.

A virus, easily passed from person to person, is suspected as the cause of the illness, Oltrogge said.

The first illness, reported June 1, occurred at Colorado River mile 52, and the most recent cases were reported near National Canyon, about 20 miles east of Lake Mead.

To date no one has been hospitalized and no emergency evacuations from the river have occurred, although up to 1,000 people are on the river at any one time, Oltrogge said.

Many Las Vegans can sympathize with the misery being felt by the river visitors who have fallen sick. A similar illness has made a run through Southern Nevada.

The Clark County Health District identified Norwalk virus -- named for Norwalk, Conn., where it was first identified -- as the possible culprit in numerous gastrointestinal illnesses reported throughout the Las Vegas Valley over the past two months.

The virus is spread through sneezing and other airborne means, as well as poor hand-washing and eating produce that hasn't been properly washed or refrigerated. In the United States, such viruses cause an estimated 23 million illnesses, 50,000 hospitalizations and 300 deaths each year, according to the federal Centers for Disease Control and Prevention in Atlanta.

While Grand Canyon officials suspect a virus, the illnesses are still being investigated.

The National Park Service is working with the U.S. Public Health Service, Coconino County Department of Health Service, Arizona State Epidemiology Office and the Centers for Disease Control and Prevention in Atlanta to determine the source of the illness.

Meanwhile, downstream sites have been made aware of the illnesses and are keeping an eye for a spread.

The Bureau of Reclamation in Boulder City is among the agencies monitoring what's going on in the Grand Canyon, spokeswoman Colleen Dwyer said. So far the bureau has not received any reports of illness from Lake Mead boaters, she said.

In addition, the Southern Nevada Water Authority, which routinely looks for viruses in the water supply from Lake Mead, did not find any viruses that would cause human upsets in recent testing, microbiologist Peggy Roefer said.

It's not the first time the Grand Canyon has had an illness spread among vacationers. Illnesses with similar symptoms occurred during the summers of 1994 and 2000, Oltrogge said.

As a result of those outbreaks, the National Park Service developed a reporting system that requires commercial river guides to immediately report any illness that occurs in three or more rafters.

The best way to halt the spread of outbreaks is through thorough and frequent hand washing with soap, handling foods safely and filtering and treating drinking water with chlorine or iodine while floating on the river, the park service said. If iodine or chlorine is not available, boiling the water for 10 minutes will disinfect it of harmful viruses.

The Associated Press contributed to this story.