Norovirus Update

River trip illnesses down from last year
By Brad Fuqua, September 24, 2003
Grand Canyon News Editor

One year after a series of norovirus outbreaks on the Colorado River, things appeared to be pretty much back to normal this summer as river runners made their way through Grand Canyon. Last year, dozens of river trip passengers fell sick to the gastrointestinal illness, the same strain that ran rampant on cruise ships. This summer at Grand Canyon, only one trip reported three or more sick passengers. The infected trip launched from Lee's Ferry on Sept. 1 and a passenger became sick the following day. As a result, there is a theory that the person may have arrived for the trip already carrying the virus.

"The first person got sick on the 2nd, so our wildest guess is that it was brought in," said Michael McGinnis, Grand Canyon National Park river sub-district ranger. "The Coconino County Health Department actually has the toilets ... they took samples and are testing for norovirus. That's what they think it is, they don't know for sure." McGinnis said it appears 13 people got sick from the incident. Two people were flown out and taken to the hospital in an evacuation done above Crystal Rapid. Last year's problems with the illness were traced to discharges from Glen Canyon Dam's water-treatment plant. This year, McGinnis said "they did testing and did not find it," so that problem has seemingly been solved.

In addition, the National Park Service, commercial river runners and public boating groups met in a series of meetings to go over sanitation practices. Out of those meetings came a policy that private or commercial boating groups must report three or more illnesses immediately via satellite phone. That happened just the one time this year.

If fewer than three people become sick with contagious gastrointestinal illness on a river trip, the boaters are not required to report it until the end of the trip. That happened 12 times this summer, including one person who had to be flown out. According to the Centers for Disease Control, symptoms of norovirus usually include nausea, vomiting, diarrhea and some stomach cramping. Sometimes people additionally have a low-grade fever, chills, headache, muscle aches and a general sense of tiredness. The illness begins suddenly is usually brief, with symptoms lasting only about one or two days, the CDC reports.