Figure 2. Rapid replacement of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants by Delta and subsequent arrival of Omicron, Uganda, 2021. A) Coronavirus disease pandemic waves. Confirmed cases of daily coronavirus disease and trends of the SARS-CoV-2 pandemic over time. Three waves of the pandemic dominated by the A.23.1 in the first wave (December 2020‒January 2021), Delta in the second wave (May‒July 2021), and the Delta and Omicron variants in the third wave (Omicron emerged in late November 2021 and the wave began in December 2021). B, C) SARS-CoV-2 variants over time (950 genomes deposited in the GISAID database [https://www.gisaid.org] by January 10, 2022). D) SARS-CoV-2 variants during the third wave among travelers and community samples. E) Violin plots showing the distribution of whole-genome nucleotide mutations in each of the SARS-CoV-2 lineages by using the wild-type Wuhan-Hu-1/2019 isolate (GenBank accession no. MN908947) as the reference. Black dots indicate median number of nucleotide mutations. Error bars indicate interquartile ranges.