The researchers compared actual trends in Covid-19 cases, hospitalizations, and deaths against a modeled trajectory of what these trends would have been if there had been no vaccinations.
By the end of June, researchers estimate there would have been about 279,000 more deaths due to Covid-19 – about 46% more than there were – and as many as 1.25 million more admissions if there were none vaccinations. And if vaccinations had come at the half-pace that they did, about 121,000 more people might have died, and more than 450,000 more would have been hospitalized.
At a briefing Thursday, White House Covid-19 Response Director Jeff Zients called this new research “a strong reminder of what is at stake in our vaccination efforts.”
“This is further evidence that our overall government strategy is working and has prevented significant further tragedy and disruption to Americans’ lives and livelihoods,” he said.
The researchers’ model considered factors including the occurrence and transmissibility of new variants, vaccine efficacy rates, mobility patterns that drive daily contacts, and age-specific risks of serious health outcomes due to Covid-19.
Most of the additional deaths would have occurred due to an “increase and spread of the more transmissible alpha variant,” according to the researchers. The alpha variant – also known as B.1.1.7 and first identified in the UK – became the dominant strain in the US in the spring. Without vaccinations, researchers estimate there could have been a spring rise of nearly 4,500 deaths each day, even more than the January peak of about 3,400 daily deaths.
The researchers compared their model with actual trends between mid-December 2020 – when vaccinations began in the US – and the end of June 2021. However, the model was simulated using data back in October 2020 to balance lower incidence with these from winter shocks. .
Nearly 48% of the US population – approx. 156 million people – are fully vaccinated according to data from the US Centers for Disease Control and Prevention. Over the past week, an average of about 432,000 people were fully vaccinated each day, which is about 76% lower than the maximum rate of nearly 1.8 million people each day in mid-April.