Older adults who are vaccinated against COVID-19 are significantly less likely to die or become seriously ill than those with natural immunity caused by previous infection of the disease, according to new research.
Researchers from the Regenstrief Institute, Indiana University School of Medicine and Vanderbilt University Medical Center compared the effectiveness of COVID-19 vaccines versus natural immunity in protecting against deaths, hospitalizations and emergency department visits of all causes, including COVID-19.
The study found the all-cause death and hospital admission rates for vaccinated individuals were 37% lower than the rates for those with natural immunity acquired from previous COVID infection, while the rate of ED visits for all causes was 24% lower for vaccinated individuals than for the previously infected. The lower death rate for vaccinated individuals was particularly impressive for individuals ages 60 and older, the researchers found.
“This study has important public health implications as previous studies investigated COVID-specific ED visits, hospitalizations and mortality but didn’t capture the non-COVID related ones,” study first author and Regenstrief Institute Research Scientist Wanzhu Tu, PhD, said in news release. “Our work confirms that mRNA vaccines have kept people out of the ED and the hospital as well as lowered the likelihood of death from any cause. And we saw this pattern in every age group.”
Using data derived from the Indiana Network for Patient Care, a central repository of clinical and administrative health data from across Indiana, researchers matched 267,847 pairs of individuals to compare those who had received vaccines versus those with previous COVID-19 infections. They then compared infection rates, as well as death rates and emergency room and hospital visits six months after the index date.
While the incidence of COVID-19 infection was higher (6.7%) for vaccine recipients than previously infected individuals with natural immunity (2.9%) six months later, the rates of death, hospitalization and ED visits from all causes including COVID were significantly lower in vaccinated individuals.
“The significantly lower rates of all-cause ED visits, hospitalization and mortality in the vaccinated highlight the real-world benefits of vaccination. The data raises questions about the wisdom of reliance on natural immunity when safe and effective vaccines are available,” the study concluded.
The article appeared in the January 2023 edition of the American Journal of Public Health.
