A new report from the US Centers for Disease Control and Prevention (CDC) highlights extensive efficacy in preventing infections from the Moderna and Pfizer-BioNTech COVID-19 vaccines.
The report shows the 2 vaccines were 90% effective in preventing infections—regardless of symptom status—14 days after the second dose was administered.
In addition, the 2 vaccines were 80% effective 14 days after the first dose, but before the second dose.
The findings come from studying nearly 4000 health care personnel, first responders, and other frontline workers from mid-December 2020 through mid-March 2021. The participants were tested weekly for 13 weeks in 8 US locations.
According to the CDC, both vaccines were given to participants in all the locations, but the timing on their availability differed. Of the vaccinated, 62.7% of participants received the Pfizer-BioNTech shot and 29.6% received the Moderna shot.
“Among fully immunized (≥14 days after second dose) persons, 0.04 infections per 1000 person-days were reported, and among partially immunized (≥14 days after first dose and before second dose) persons, 0.19 infections per 1000 person-days were reported,” the CDC stated on their website.
“These findings indicate that authorized mRNA COVID-19 vaccines are effective for preventing SARS-CoV-2 infection, regardless of symptom status, among working-age adults in real-world conditions,” the CDC stated.