Impact of the Delta Variant on Transmission, Vaccine, and Treatment Efficacy
June 21, 2021
One of the consequences of unchecked SARS-CoV-2 infections is the generation of mutations that have the potential to increase infectivity and transmissibility, confer a degree of resistance to vaccines, neutralizing antibodies, and monoclonal antibody therapy, and in some cases generate false negatives in RT-PCR tests. We have discussed some of these variants in previous Perspectives. The variant du jour is the Delta variant (B.1.617 lineage) that has arisen in India and contains a suite of 13 characteristic mutations. Questions about the new variant are similar to those arising from the appearance of the earlier variants. Is it more infectious? More lethal? Is it better able to infect people who have been vaccinated or previously infected? And will it be necessary at some point for vaccinated people to get booster shots? If so, when?