Greek letter used for a 2021 Covid variant

The Greek letter Delta is the answer to the crossword question regarding the Covid variant that emerged in 2021. This variant, also known as B.1.617.2, was first identified in India and has since spread to other parts of the world. The Delta variant is believed to be more transmissible than previous strains of the virus, making it a cause for concern among health officials. Despite the challenges posed by this variant, efforts are underway to contain its spread through vaccination campaigns and other public health measures.