SARS Cov 2 Delta

About SARS Cov 2 Delta

The Delta variant B 1 617 2 was first identified in India in October 2020 and designated a Variant of Concern in May 2021. Delta was estimated to be roughly twice as transmissible as the original strain. It caused devastating outbreaks in India in April to May 2021, and excess mortality studies suggest deaths far exceeded official reports. Delta spread to over 180 countries and became dominant globally by mid 2021. Delta caused more severe disease than previous variants, with studies suggesting roughly twice the hospitalization risk. Vaccine effectiveness against Delta infection was reduced but protection against severe disease remained high. The Delta wave motivated acceleration of vaccination campaigns globally. In the US, the Delta surge in summer 2021 primarily affected unvaccinated populations in southern states. Delta demonstrated how a more transmissible and virulent variant could reverse pandemic progress. The variant was eventually displaced by Omicron in December 2021.