Current SARS-CoV-2 Variants of Concern
Alpha (B.1.1.7) was the first identified major variant of concern. It was first identified in the United Kingdom in the fall of 2020 and spreads approximately 50% better than the original SARS-CoV-2. There is some evidence that the Alpha variant may cause more severe disease. Current SARS-CoV-2 vaccines and monoclonal antibody therapies appear to be effective against the Alpha variant.
The variants Beta (B.1.351), first identified in South Africa, and
Gamma (P.1), first identified in Brazil, both exhibit increased transmissibility, but not as much as the Alpha variant. Some of the current monoclonal antibodies are less effective against the Beta and Gamma variants. Both Beta and Gamma variants are less well neutralized by antibodies in vaccinated individuals, and there is a small decrease in the effectiveness of currently available vaccines against these 2 variants.
Delta (B.1.617.2) is currently the most prevalent variant in the United States. Early data suggest that the Delta variant spreads almost twice as quickly as the original SARS-CoV-2 virus. It is not yet clear whether Delta causes more severe disease. The Delta variant may not be neutralized as well by antibodies in vaccinated people. Early data suggest a small decrease in vaccine effectiveness in patients who are fully vaccinated against SARS-CoV-2. However, individuals who have received only a single dose of a 2-dose vaccine regimen are much less protected against the Delta variant. People who have not received a COVID-19 vaccine are at high risk of becoming infected with the Delta variant because of its increased transmissibility.
Surveillance programs will continue to monitor for SARSCoV- 2 variants and the possible implications of these variants for disease spread, treatments, and vaccines. Vaccination is safe and remains the most effective way to prevent severe disease and limit spread of SARS-CoV-2.
https://www.cdc.gov/coronavirus/2019-ncov/variants/variant-info.html#Concern
Videos
https://youtu.be/EAR0Tsq6srA?t=21960
https://www.youtube.com/watch?v=X3Sd3b7ZPn8
https://www.youtube.com/watch?v=Cw3BIr1dRNc&list=PLZ8RoZIYEDV3yaOiTwtyWSqukKdAPGnL9&index=9