AURORA, Colo. (CBS4) – New research from the Centers for Disease Control and Prevention suggests the Moderna COVID-19 vaccine is the most effective against the delta variant. The new report from the agency analyzed data from 187 hospitals and 221 emergency departments and urgent care clinics across 9 states, including Colorado. It found the Moderna vaccine was 95% effective at preventing hospitalizations against the Delta variant in adults. Pfizer was 80%, while Johnson & Johnson was 60%.
“Hospitalization is really the important measure because we really want to keep people from getting sick enough to have to be admitted to the hospital,” said Dr. Thomas Campbell, professor of medicine and chief clinical research officer for UCHealth.
Campbell said the study shows Moderna’s vaccine efficiency was also higher in emergency department and urgent care encounters, which suggests it’s also slightly better at preventing infection. For those figures, Moderna was found to be 92% effective, and Pfizer was 77%.
“When we were talking about vaccines a year ago, the bar we were aiming for was 60% effective,” Campbell said. “We’re still in the 70% range and greater for all measures, so both of these vaccines are still highly effective.”
According to Campbell, the gap in outcomes could be due to a number of factors, including the fact that Moderna’s vaccine carries more RNA per two doses than Pfizer’s. Differences in the ages and health conditions of the people who got each vaccine could have also affected the findings.
He said the results of the study align with the findings of several other recent reports on vaccine effectiveness versus the delta variant, but ultimately, any vaccine is better than none.
Currently, about 82% of UCHealth patients hospitalized for COVID-19 are unvaccinated.
“I think the choice of either Pfizer or Moderna is still an excellent choice,” he said. “I would not recommend one over the other at this time.”
Jonathan Mendez, a microbiologist, said the findings of the CDC report give him peace of mind.
“It was really exciting,” Mendez said. “It’s more than I could have hoped for.”
In 2020, Mendez was among the first to sign up for UCHealth’s clinical trial for the Moderna COVID-19 vaccine. While he later learned he was in the placebo group, he received the Moderna vaccine in January.
“The fact that this is still as effective or comparably effective against some of these new, the delta variants… It’s really exciting and more than I could have hoped for.”