Figure 8. Animals were infected with AY.20, a rare variant of SARS-CoV-2.

a) Virus from each of the 11 lions collected on October 14, 2021 and Hyena A collected on October 28, 2021 (first positive test for each animal) were sequenced and determined to be Delta lineage AY.20. Consensus whole genome sequences were aligned (numbers represent nucleotide position), with vertical lines representing single nucleotide polymorphisms between viruses. For each lineage, the b) number of cases and c) frequency as a percentage of all human SARS-CoV-2 sequences reported in Colorado in October 2021 (n = 20,051) were plotted by date. Red line shows lineage AY.20. Red, orange and blue arrows represent the date of first positive test in tigers, lions and hyenas respectively. d) States and countries with full genome sequences from tigers and lions (n = 109, Colorado in red, complete list in Supplemental Table 3). e) For each tiger/lion sequence, the frequency and rank of that lineage in humans in the same state/country in the week prior to infection was calculated (complete list in Supplemental Table 4).