Omicron BA.5 and BA.2.75: is the End of the COVID-19 Pandemic Near?

COVID-19 mRNA virus (SARS-CoV-2) evolves constantly. Selective pressure has driven change from the ancestral strain into several variants-of-concern (VOC) during the pandemic. The latest VOC is Omicron (PANGO lineage B.1.1.529). Omicron further branched into several highly transmissible and immune-evasive sub-variants, for example, BA.1, BA.2, BA.2.12.1, BA.4 and BA.5. These novel sub-variants differ significantly and meaningfully from original Omicron. As of July 2022, BA.5 sub-variant progressively displaces earlier sub-variants, BA.2.12.1, BA.2 and BA.4, in many countries. BA.5 is driving a global epidemic wave due to its extreme biologic properties of immune escape and transmissibility. In addition, the novel Omicron sub-variant BA.2.75 first reported in India and became the dominant Indian strain during late August 2022, has now spread to different countries. This variant of concern sparks fears of another COVID-19 wave in these countries. This paper provides a comprehensive review of Omicron BA.5 and BA.2.75 with a focus on properties of immune evasion and severity of illness for each. Variant impacts on COVID-19 treatments are also discussed.