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What to know about the delta variant
The delta variant has become the dominant strain of COVID-19 in the U.S. in the summer of 2021, driving up cases and hospitalizations.
SAN FRANCISCO - As the nation braces for yet another potential surge in COVID-19 infections and cold weather approaches, new data suggests an estimated 90,000 COVID-19 deaths in the United States could have been prevented since June 2021.
The analysis, conducted by the Kaiser Family Foundation, estimated how many COVID-19 deaths were among unvaccinated adults and could have been prevented since June 2021 "when safe and effective COVID-19 vaccines became widely available to all adults in the U.S."
Medical personnel move a deceased patient in New York City. (Photo by Angela Weiss / AFP) (Photo by ANGELA WEISS/AFP via Getty Images)
"From June through September 2021, approximately 90,000 COVID-19 deaths among adults likely would have been prevented with vaccination," the organization wrote. "Most of these preventable deaths occurred in the last month, well after vaccines became available. In September 2021 alone, approximately 49,000 deaths likely would have been averted if they had chosen to get vaccinated against COVID-19."
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To estimate the number of COVID-19 deaths among adults that could have been prevented with vaccines, the organization looked at COVID-19 deaths among unvaccinated people in the months after vaccines were widely available (June through September 2021).
From there, the foundation added COVID-19 deaths up in each month since June and subtracted COVID-19 deaths among children age 0-17 years. Then, they subtracted COVID-19-related deaths among vaccinated people with a breakthrough COVID-19 infection from total COVID-19 deaths among adults in each month.
A recent study by the U.S. Centers for Disease Control and Prevention showed age-standardized vaccine effectiveness against deaths of 91% in the June 20–July 17 period. Based on this study, the foundation assumed 91% of COVID-19 deaths among unvaccinated people likely would have been prevented with COVID-19 inoculations.
RELATED: US COVID-19 deaths top 700,000 as delta variant fuels pandemic
The organization also found that COVID-19 was the second leading cause of death in September and the number one cause of death for people age 35-54.
Earlier this month, the COVID-19 death toll in the U.S. reached a grim milestone of 700,000 people, and the number is still climbing daily.
The number of lives lost, as recorded by Johns Hopkins University, is greater than the populations of Las Vegas, Nashville and Boston. It’s also greater than the number of cancer deaths in the U.S. in 2019.
"To heal we must remember, and as our nation mourns the painful milestone of 700,000 American deaths due to COVID-19, we must not become numb to the sorrow," President Joe Biden said in a statement marking the death toll. "On this day, and every day, we remember all those we have lost to this pandemic and we pray for their loved ones left behind who are missing a piece of their soul."
The U.S. leads the world in coronavirus-related deaths. Globally, nearly 4.9 million people have died of COVID-19, according to Johns Hopkins data.
This story was reported from Los Angeles.