190 Yellowstone employees test negative for COVID-19 in fourth round of surveillance tests
By Moosetrack Megan

Posted: July 1, 2020
MAMMOTH HOT SPRINGS, WY – In the fourth round of surveillance testing on Yellowstone employees, all tests came back negative. On June 17 and 18, National Park Service (NPS) employees, with assistance from local and state health officials, tested 190 employees from the NPS and concession companies operating in the park.

Initially, one concession employee tested positive and was immediately isolated. The employee was retested twice more, and both tests came back negative. The state health office described the initial test as a “false positive” and the employee has returned to work. According to the county health officer, a small percentage of “false positives” are normal in widespread surveillance testing.
The total number of Yellowstone-employee tests completed since late May is 577. The week of June 22, 162 tests were conducted, and those results are pending. Moving forward, the park will continue to test employees in partnership with Montana and Wyoming.
As introduced in the park’s reopening plan, this surveillance testing will continue throughout the summer and target employees who are first responders and/or work directly with the public. More information about the surveillance testing effort is available in the park’s news release from June 4.
Additionally, the park sampled wastewater systems in Gardiner, Mammoth Hot Springs, and Old Faithful between June 13 and 16. Lab results indicated 0% prevalence of COVID-19 in those systems at the time they were sampled. Additional samples were taken at Mammoth Hot Springs and Old Faithful between June 27 and 29, which may give the park a better idea of COVID-19 increases due to reopening.
Visitation Statistics for June 16-29, 2020  


Vehicle counts


2020 percent of 2019 visitation


June 16-29, 2020

June 16-29, 2019







Wyoming Entrances

(East and South)




Montana Entrances

(North, West, Northeast)




Stay informed about changes to park operations due to COVID-19. Download Yellowstone’s App, and visit www.nps.gov/yell and the park’s social media channels.