COVID-19 is the disease caused by SARS-CoV-2, and resulted in a global pandemic in 2020. Due to community spread of the virus throughout the United States and other countries, there has been interest in developing a vaccine to hopefully stop the spread of the virus.

In November 2020, Pfizer and Moderna announced their COVID-19 vaccines were more than 90% effective according to early trial data. Both vaccines require two doses per person. Government officials expect there to be 40 million doses from the Pfizer and Moderna vaccine available in 2020 if both vaccines are approved, enough to vaccinate 20 million people. (Washington Post) By the end of 2021, Pfizer estimates it will be able to produce 1.3 billion doses, and Moderna estimates it will be able to produce 1 billion doses. (The Guardian)

Based on a chart from an analysis by McKinsey, a 90% effective vaccine covering 50% of the population, along with an additional ~15% natural immunity level, may be sufficient to achieve herd immunity. This model assumes that immunity is reached when the immune population reaches 58%, calculated from the expression 1 − 1/R₀, where R₀ is 2.4.

When will 150 million Americans be vaccinated against COVID-19?

This question will resolve as the date when 150 million Americans (people residing in the United States) have been vaccinated for COVID-19, according to a reliable media or reliable official government source. If this does not resolve before 01 January 2023, it resolves as >01 January 2023.