Here's How Many CA Lives Were Saved By COVID Vaccines: Study

CALIFORNIA — Before the COVID-19 vaccines were introduced, the only tools available to evade the rapidly spreading virus were social distancing, hand washing and masking.

The Pfizer, Moderna and Johnson & Johnson vaccines ushered in a new phase of the pandemic and allowed Californians living in the most populous state to return to a semblance of normalcy.

A new study from a partnership between researchers at UC San Francisco and the California Department of Public Health presents just how many lives were saved by the shots and what life might have looked like without them.

Within the first 10 months, the vaccines prevented an estimated 1.5 million infections, 73,000 hospitalizations and 20,000 deaths in the Golden State, according to the study, COVID-19 Vaccination and Estimated Public Health Impact in California, which was published by the JAMA Network.

The study also found that the vaccines contributed to an estimated 70 percent reduction in cases.

Vaccines helped especially in corralling the deadly and highly transmissible delta surge, in which researchers estimated that more than 65 to 90 percent of cases were averted after the delta variant became the dominant variant.

"The burden of COVID-19 cases and more severe outcomes would have been significantly greater in the absence of vaccination, including in the Omicron surge," researchers wrote.

Researchers also illustrated how California might have fared without the vaccines, using a pair of statistical models. In one model, coronavirus infection rates were calculated from November 2020 to October 2021 in children 11 and under — the only population ineligible to receive a shot at the time. That infection rate was applied to the rest of the population.

A second model separated vaccine-eligible groups into four sections and analyzed the estimated risks of infection, hospitalization and death for each population.

The first model showed that the first 10 months of the vaccination campaign prevented 1.52 million infections, compared with the second model, which estimated that the shots subverted fewer infections but prevented more hospitalizations and deaths.

The results of the study "provides evidence of the public health benefit of COVID-19 vaccination" and continuing the shots, authors said.

“The impact that vaccines have had, and the findings that we have, are dramatic,” Dr. Nathan Lo, an infectious disease specialist at UCSF and a co-author of the study, told the Los Angeles Times.

Each of infection avoided represents an opportunity to "allow people to actually go to work, to be with their family safely, to not have such socioeconomic disruption," he told the newspaper.

Another study from the Commonwealth Fund estimated that vaccines have saved 2.2 million lives and 17 million hospitalizations in the U.S. since they were first introduced.

On Tuesday, CDPH reported that the state's testing positivity was 2.7 percent, which has crept up from 1.7 percent on April 8.

In California, 74,815,999 total vaccines administered, and 82 percent of the eligible population — 5 and up — has been vaccinated with at least one dose, according to the state.