Yellowstone National Park continues to test its employees for the coronavirus. In partnership with the states of Montana & Wyoming, over 1,000 COVID-19 tests have been given to front-line Yellowstone employees over the past eight weeks. The results of those tests have netted zero positive cases to date.Two concession employees, however, and three visitors with COVID-19 symptoms did test positive  

About 200 tests are currently pending.
  • Total tests conducted to date: 1,237
  • Total tests with negative results: 1,032
  • Total tests with positive results: 0
  • Total tests results pending: 205
Regarding the two Yellowstone concession employees who tested positive for COVID-19: They were isolated and mitigation steps were taken in accordance with CDC (Centers for Disease Control and Prevention) guidance. Officials also conducted contact tracing for individuals who they were in contact with. Several other employees were quarantined as a precaution
The first employee experienced COVID-19 symptoms while away from the park and was tested outside the park. Once the positive test was confirmed, the employee was isolated. Based on contact tracing by health officials, the employee had limited interactions with visitors or employees. It is likely this employee contracted the virus while out of the park.
These two cases are the first positive tests out of the nearly 2,000 concession and National Park Service employees who work in the park.
Park Visitors & COVID-19
Three separate visitors have tested positive recently after being in the park. One visitor spent one night in the park, the other did not stay overnight. Park officials don't believe that these visitors had the virus prior to entering Yellowstone. A third visitor was tested outside the park after visiting for a week. It has not been determined if the virus was contracted while the visitor was in the park or prior to entering.
These are the first park visitors out of an estimated 1.4 million visits since the park opened who had symptoms while in the park and tested positive after seeking medical attention.
“At this point, a limited number of cases have appeared in different locations around the park,” said U.S. Public Health Officer, George Larsen. “Currently, there is no indication of any type of community spread in the park although we are monitoring it very closely.”
Yellowstone National Park Superintendent Cam Sholly is asking people to please not visit the park if you're showing symptoms of coronavirus. “If you have symptoms as your visit is approaching, do the responsible thing and don’t come to the park. You end up putting our employees, health care providers, and other visitors at risk," said Superintendent Sholly. "Our thanks once again to the states of Wyoming and Montana (Park County, Wyoming, and Park County, Montana), for assisting us with testing capacity and additional public health expertise.”
Wastewater Testing
The park has participated in four rounds of wastewater testing which allows them to monitor levels of COVID-19 in the wastewater in some of the park's most popular developed areas. These tests took place in counties in Montana and Wyoming that are adjacent to Yellowstone.
Samples taken in May and early June were COVID-19 free. Samples taken in late June at two of the most populated areas indicated a low-level detection of the virus, within 10% of the lowest measured across over 400 jurisdictions across the United States participating in this type of testing.
Recent sampling conducted in mid-July indicated a prevalence level slightly lower than samples taken in late June. The park intends to continue this testing in partnership with the Wyoming Department of Health.