Positive COVID-19 tests reported in Yellowstone National Park


YELLOWSTONE NATIONAL PARK – More than 1,000 COVID-19 tests have been performed on Yellowstone employees in the past eight weeks, with 2 dealership employees and 3 visitors with COVID-19 symptoms testing positive. There have been no positives to date with frontline employees.

The tests were conducted in association with the states of Montana and Wyoming and the surrounding counties.

A further 455 tests were recently confirmed negatively in the fifth (162 tests), sixth (244 tests), and ninth (49 tests) round of tests, bringing the total number of confirmed negative tests to 1,032. About 200 tests are currently pending. More information on the surveillance testing effort is available in the park’s press releases dated June 30th [nps.gov] and June 4 [nps.gov].

  • Total tests performed to date: 1,237
  • Total tests with negative results: 1,032
  • Total tests with positive results: 0
  • Total pending test results: 205

Confirmed symptomatic cases

Yellowstone Employees Two Yellowstone dealership employees with symptoms recently tested positive for COVID-19. Once positive tests were confirmed, these employees were isolated and mitigation measures were taken in accordance with the guidelines from the Centers for Disease Control and Prevention. Consequently, health officials led the tracing of contacts.

According to a press release, the first employee experienced symptoms of COVID-19 while outside the park and was examined 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. This employee likely contracted the virus while out of the park.

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The second employee had symptoms while in the park, was examined at the clinic, and was found to be positive. The employee was immediately isolated while contact tracing occurred. Several other employees were quarantined as a precautionary measure. Surveillance tests for the week of July 20 were concentrated in and around the area where the positive employee worked. About 40 people were evaluated with assistance from Park County, Wyoming, health officials, and all tests came back negative. As a precautionary measure, approximately 10 additional health officials and first responders were also evaluated with negative results.

The park is closely monitoring new cases with its county health and business partners. No further information will be released to protect the privacy of each employee. These are the first positive tests of the nearly 2,000 concession and National Park Service employees working in the park in the past two months.

Visitors Three separate visitors recently tested positive after being in the park. These visitors sought medical assistance at Yellowstone clinics, were evaluated and tested positive. One visitor spent one night in the park and the other did not stay overnight. These visitors most likely had the virus before entering the park. The third visitor was tested outside the park after visiting for a week. It has not been determined whether the virus was contracted while the visitor was in the park or before entering.

These are the first visitors 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 United States Public Health Officer George Larsen. “Currently, there is no indication of any type of extended community in the park, although we are closely monitoring it.”

“Some of these visitor cases had symptoms before entering the park,” said Superintendent Cam Sholly. “If you have symptoms as your visit approaches, do the responsible and don’t come to the park. You end up putting our employees, healthcare providers and other visitors at risk. Once again, we thank the states of Wyoming and Montana (Park County, Wyoming, and Park County, Montana) for helping us with assessment capacity and additional public health expertise. “

Wastewater test

The park has participated in four rounds of wastewater testing with several surrounding counties in Wyoming and Montana. The information collected allows the park to monitor COVID-19 levels in wastewater in the park’s most popular developed areas.

The first two samples of wastewater from the park taken in May and early June detected zero presence of COVID-19. Samples taken in late June in two of the most populous areas indicated low-level detection of the virus, within the lowest 10% of measurements measured in more than 400 jurisdictions in the United States participating in this type of testing. The most recent sampling in mid-July indicated a slightly lower prevalence level than the samples taken in late June. The wastewater test for COVID-19 is a new technology and the interpretation of the results is not well understood. At this time, the park hopes the results will be useful in identifying trends.

Going forward, the park, in association with the Wyoming Department of Health, will collect and analyze wastewater samples for one year to better protect public health.