CDC Study: COVID Vaccines Are Effective
Abt Partners With CDC on NEJM Study Showing COVID-19 Vaccines Effective At Preventing and Moderating Effects of Infections
Rockville, Md. – A forthcoming New England Journal of Medicine article on a Centers for Disease Control and Prevention (CDC) study shows COVID-19 vaccines are highly effective among working-age adults in real-world conditions. Abt Associates partnered with the CDC on the study, which showed that the vaccines not only prevent SARS-CoV-2 infections but also reduce serious symptoms among those with breakthrough infections despite vaccination. The study was released in preprint via medRXiv.
This publication pools data from two CDC-funded studies: Research on the Epidemiology of SARS-CoV-2 in Essential Response Personnel (RECOVER), an Abt-led study, and Healthcare, Emergency Response, and Other Essential Workers Surveillance (HEROES), which is run by University of Arizona. A group of 3,975 healthcare personnel, first responders, and other essential and frontline workers completed weekly SARS-CoV-2 nasal swab testing from December 14, 2020, to April 10, 2021. They were located in eight locations, six of which are managed by the Abt team under RECOVER: Tucson, Arizona; Miami, Florida; Duluth, Minnesota; Portland, Oregon; Temple, Texas; and Salt Lake City, Utah. The University of Arizona manages the other two locations, which are in Arizona.
The results showed that adjusted vaccine effectiveness for full vaccination was 91% against symptomatic or asymptomatic SARS-CoV-2 infection. For partial vaccination, the effectiveness rate was 81%. Moreover, among partially or fully vaccinated participants with SARS-CoV-2 infection, the viral RNA load was substantially reduced compared with the load in unvaccinated study participants, the data showed. That means less of the virus causing COVID-19 was present. For those vaccinated, the risk of self-reported fevers was 58% lower, and they spent 2.3 fewer days sick in bed than those who were not vaccinated.
“It’s heartening to see that vaccines operating in the real world can effectively prevent the vast majority of COVID-19 infections—and, moreover, can moderate the impact of those ‘breakthrough’ infections when they do occur,” said Lauren Olsho, the Abt principal investigator on the study and an Abt principal associate.
Such studies “increase the public’s knowledge and understanding of COVID-19,” adds Project Director Danielle Hunt, an Abt vice president and senior epidemiologist. “The data we bring to the table can help produce evidence-based policies.”
About Abt Associates
Abt Associates is a global consulting and research firm that uses data and bold thinking to improve the quality of people’s lives. From combatting infectious disease and conducting rigorous program evaluations, to ensuring safe drinking water and promoting access to affordable housing—and more—we partner with clients and communities to tackle their most complex challenges. http://abt.associates/cdcsolutions