Norwalk Talk

The Norwalk virus and the fact that it made more than 130 Grand Canyon river runners sick this last summer garnered national attention with press in major newspapers and through the involvement of the Center for Disease Control (cdc). New reports show that water flowing into the Colorado River from the sewage treatment plant inside Glen Canyon Dam may be the culprit. Ironic to be sure. As many of you know, and too many have experienced first-hand, the Norwalk virus is a highly infectious agent that causes acute gastrointestinal illness. While most healthy adults recover within 24–48 hours, it can pose health risks for the immuno-compromised, the elderly and the very young.
Chuck Higgins, the regional public health consultant for the National Park Service in Denver, recently addressed attendees of the Grand Canyon River Guides Fall Meeting on November 2nd. Chuck informed us that work is now underway to break down the genetic code of the viral strains found in the river and in the treated wastewater to see if they match.

Should the virus prove to be resistant to the level of chlorine used in the wastewater treatment plant, there will be ramifications—from the way that water is treated, to the way river guides filter their water while on the river. It may have national implications as well since Norwalk-type viruses are commonly present among the general population.
Much more work will be done in the ensuing months to substantiate the source as well as develop protocols for prevention. The Park Service will be working together with the Coconino County Health Department, the Grand Canyon river outfitters, and members of Grand Canyon River Guides to mesh science with practicality and feasibility as much as possible. Look for more information in upcoming bqr’s and at the spring Guides Training Seminar. The heat is on to finalize their findings and review all public health related practices on the river before the start of another river season.
If you are interested in viewing the preliminary summary of the outbreak investigation, you may contact the gcrg office for a copy of this scintillating document. We’ll be in touch!