Study confirms vaccine benefit
Aaron Glatt, MD, chair of medicine at Mount Sinai South Nassau in Oceanside, New York, and a spokesman for the Infectious Disease Society of America, said in an interview that the study is important because it confirms the benefit of COVID-19 vaccination.
Regardless of whether the study’s results are statistically valid, he said, “I don’t think anyone can argue the benefit isn’t there. It’s a question of how important the benefit is.”
Dr. Glatt is not surprised that there are variations across states in the number of COVID-19 deaths averted through vaccination. “Clearly, in states where there was a lot of disease, a significant amount of vaccination is going to impact that tremendously.”
The authors note that their paper has some limitations. For one thing, they couldn’t determine what share of the estimated reduction in COVID-19 deaths was a result of the proportion of the population that was vaccinated or had antibodies and what share was a result of lower population-level risk for COVID-19 transmission.
Vaccination versus natural immunity
In addition, the researchers weren’t able to identify the roles of vaccination, natural immunity, and changes in mobility in the numbers of COVID-19 deaths.
Dr. Glatt says that’s understandable, since this was a retrospective study, and the researchers didn’t know how many people had been infected with COVID-19 at some point. Moreover, he adds, scientists don’t know how strong natural immunity from prior infection is, how long it endures, or how robust it is against new variants.
“It’s clear to me that there’s a benefit in preventing the second episode of COVID in people who had a first episode of COVID,” he said. “What we don’t know is how much that benefit is and how long it will last.”
The researchers also didn’t know how many people had gotten both doses of the Pfizer or the Moderna vaccine and how many of them had received only one. This is an important piece of information, Dr. Glatt said, but the lack of it doesn’t impair the study’s overall finding.
“Every vaccine potentially prevents death,” he stressed. “The more we vaccinate, the more deaths we’ll prevent. We’re starting to see increased vaccinations again. There were a million of them yesterday. So people are recognizing that COVID hasn’t gone away, and we need to vaccinate more people. The benefit from the vaccination hasn’t decreased. The more we vaccinate, the more the benefit will be.”
A version of this article first appeared on Medscape.com.