October 25, 2021

Denver Zoo’s 11 African Lions Test Positive for COVID-19

November 3 Update: All 11 African lions are still testing positive for COVID-19, but keepers say the lions’ symptoms are improving. 


On October 25, we shared that our 11 African lions, ranging in age from 1 to 9, tested positive for the virus that causes COVID-19. After their keepers observed coughing, sneezing, lethargy and nasal discharge, the lions tested presumptive positive through nasal swab samples at the Colorado State University Veterinary Diagnostic Laboratory in Fort Collins, CO. The results were also confirmed positive by the United States Department of Agriculture’s National Veterinary Services Laboratories. Animal care and veterinarians describe their symptoms as relatively mild at this point, and are closely monitoring and treating the lions individually as needed.

“There have been a number of big cats to come down with COVID-19 at zoos throughout the country, including our two tigers, Yuri and Nikita,” said Brian Aucone, Senior Vice President for Life Sciences for the Zoo. “Fortunately, the vast majority have fully recovered, and the upside is that there’s an established knowledge base for us to draw from to help treat our animals. We’ve been in touch with other zoos that have also recently managed COVID cases in their big cats to inform the care we’re providing.”

The Zoo is home to two African lion prides—the first made up of brothers Jasiri, Usiku, Bahati and Kito (age 6); and our family group with males Tobias (age 5), Tatu (age 2) and Oskar (age 1), and females Neliah (age 9), Sabi (age 9), Kamara (age 6) and Araali (age 1). They all started showing symptoms soon after we announced that Yuri and Nikita had tested positive; however, there is no indication that the two groups of positive cases are connected.

Since the beginning of the COVID-19 pandemic, we have taken extraordinary measures to safeguard the health of its guests, staff, and animals. We’ve worked closely with a number of partners to develop effective health and safety protocols, including Colorado Department of Public Health and Environment (CDPHE), Denver Department of Public Health and Environment (DDPHE), Colorado Department of Agriculture (CDA) and United States Department of Agriculture (USDA). Our animal care staff adheres to strict COVID-19 protocols around our animals, including required use of personal protective equipment, hygiene, cleaning, employee self-screening, and health management.

Similar to Yuri and Nikita, none of the lions had been vaccinated against COVID-19, but our veterinarians are planning to vaccinate them along with the tigers as soon as more doses of the animal-specific Zoetis vaccine become available. We will continue to provide health updates as their status changes.

For a health update on our Amur tigers, Yuri and Nikita, please click HERE.


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