Delta variant. President Joe Biden said the announcement showed that America needs to "do better" on vaccinations, adding that a vaccine mandate for the country's more than two million federal workers was now "under consideration." COVID-19 vaccination remains the most effective means to achieve control of the pandemic.
In the United States, COVID-19 cases and deaths have markedly declined since their peak in early January 2021, due in part to increased vaccination coverage.
However, during June 19–July 23, 2021, COVID-19 cases increased approximately 300% nationally, followed by increases in hospitalizations and deaths, driven by the highly transmissible B.1.617.2 (Delta) variant* of SARS-CoV-2, the virus that causes COVID-19.