Nearly 1,400 Yellowstone employee surveillance tests conducted on front-line employees with zero positives
By Moosetrack Megan

Posted: August 19, 2020
Employee Surveillance Testing
In partnership with the states of Montana and Wyoming and surrounding counties, Yellowstone National Park has conducted nearly 1,400 employee (asymptomatic) surveillance tests since early June (346 tests in the past three weeks) on front-line employees and all test results have been negative. More information about the surveillance testing effort is available in park news releases dated June 30 and June 4.
  • Total tests conducted to date: 1,499
  • Total tests with negative results: 1,378
  • Total tests with positive results: 0
  • Total tests with results pending: 121
Zero-Positive Symptomatic Cases in Visitors or Employees
Yellowstone employees
The two Yellowstone concession employees who tested positive for COVID-19 in July have recovered. These cases are no longer active, and no other employees have tested positive in the previous four weeks out of a workforce of approximately 2,000. In accordance with the Centers for Disease Control and Prevention guidance, the park continues to proactively quarantine employees who have symptoms.
No visitors have tested positive in the last four weeks in any of Yellowstone’s medical clinics. There have been approximately 1.66 million visits to the park since it opened on May 18.
Wastewater Testing
The park continues to test wastewater with several surrounding counties in Wyoming and Montana. Information gathered allows the park to monitor levels of COVID-19 in wastewater at the park’s most popular developed areas (Mammoth Hot Springs and Old Faithful).
Recent samples taken from the Mammoth Hot Springs wastewater system indicated non-detectable levels of COVID-19. Samples taken from the Old Faithful system indicated near non-detectable levels. Visit Wyoming Department of Health Wastewater Monitor for details.
Wastewater testing for COVID-19 is a new technology and interpretation of the results is not well understood. At this time, the park hopes that results will be useful to identify trends.
The park, in partnership with the Wyoming Department of Health, will routinely take and test wastewater samples for a year to best protect public health.
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