Norovirus can turn up in the most unexpected places, like in the middle of a forest in Tennessee. Though on second glance its old habits shine through, particularly its close association with people (we are its only host) and its ability to hang around in water.
Since mid-June, over 500 people have reported becoming sick after attending a popular zipline attraction in Gatlinburg. In the past few days the water system was identified as a likely source of the issue due to fecal contamination of the water, as the Tennessee Department of Health announced last Thursday.
Earlier news reports were perhaps more focused on E. coli (and it is admittedly much more difficult to test water samples for norovirus), yet norovirus has been identified from multiple people who visited the attraction (including one person who had norovirus and E. coli).
The zipline company has been working with the public health officials, and temporarily closed the attraction a few days ago to sanitize their facility. They added filtration to their well system, began distributing bottled water, and issued refunds to their patrons.
The investigators think additional modes of transmission may have been involved in spreading the virus, such as through touching contaminated surfaces and via person-to-person spread.
This is the first time we’ve heard of a zipline-related outbreak of norovirus, but the virus does cause misery at outdoor events from time to time.
A couple of years ago at a Tough Mudder race, a sick participant is thought to have contaminated the track and lead to a number of participants starting the race after them to get sick. Last year, a norovirus outbreak at a series of outdoor festivals was traced back to fecally-contaminated drinking water. In this case, it is thought a septic system on the site was leaking waste into the local groundwater, contaminating a well.
We will update this story if more information becomes available.