2 Years of the COVID-19 Vaccine: How Many Severe and Fatal Infections Have Been Prevented?

Today, December 13, marks 2 years since the first US patients received a COVID-19 vaccine.

The first American to receive a COVID-19 shot outside of a clinical trial was critical care nurse Sandra Lindsay. “It didn’t feel any different than taking any other vaccine,” Lindsay said at the time.

Of course, the COVID-19 vaccine was different due to its potential to help end the worst of the global pandemic. In the 2 years since the first doses were rolled out, the US has administered over 655 million COVID-19 vaccines. The Commonwealth Fund estimates 80% of Americans have received at least 1 COVID-19 shot.

Commonwealth Fund investigators conducted a study to simulate disease transmission if there had been no COVID-19 vaccines. They concluded that the US COVID-19 vaccination program prevented 120 million additional COVID-19 infections, as well as over 18.5 million hospitalizations and 3.2 million deaths.

Using the reported COVID-19 incidence per 100000 Americans, the investigators estimated severe and fatal disease in a scenario without COVID-19 vaccines. They utilized a computer model of disease transmission to calculate averted hospitalizations and deaths from December 2020-November 2022. The investigators included age-stratified demographics and risk factors to ensure the best estimate of the immunological differences in vaccination and infection.

Since December 12, 2020, the US reported 82 million infections, 4.8 million hospitalizations, and 798000 deaths. With vaccinations, the investigators calculated the US would have had 1.5 times more infections, 3.8 time more hospitalizations, and 4.1 times more deaths.

Vaccines reduced both COVID-19 incidence and symptom severity. Thus, in addition to avoiding additional infection, illness, and death, the COVID-19 vaccination program likely saved the US $1.25 trillion in medical costs.

“The impact of the vaccination program is more remarkable given the challenges posed by the multiple variants that have arisen,” the study authors wrote. Indeed, the continually mutating Omicron variant has proven exceptionally infectious and evasive. The US Centers for Disease Control and Prevention (CDC) currently estimates the Omicron BQ.1.1 and BQ.1 variants are responsible for a combined 68% of COVID-19 infections.

Even with the ceaseless mutations of COVID-19, vaccines have remained effective. Now, bivalent COVID-19 vaccines offer even higher levels of protection against these emerging strains. Notably, COVID-19 vaccines also helped keep children in school.

The effective curbing of COVID-19 infections proves especially vital now, when we are seeing unprecedented cases of influenza and RSV. “Moving forward, the investigators concluded, “accelerating uptake of the new booster will be fundamental to averting future hospitalizations and deaths.”