Over the past few months, there have been concerns over how effective and how safe the AstraZeneca COVID-19 vaccine really is. But results from the most recent clinical trial, announced on March 22, have shown it to be 79% effective and with no serious side effects. Maureen Ferran, a virologist at the Rochester Institute of Technology, answers five questions about the AstraZeneca vaccine’s safety and efficacy, and when it might be available for U.S. residents.
Overall, the studies show that the AstraZeneca vaccine is effective at preventing disease caused by the original strain of SARS-CoV-2. However, evidence is emerging that it isn’t very good against some of the new variants of SARS-CoV-2.
In a small preprint study that has yet to be peer reviewed, researchers found that the AstraZeneca vaccine is only 22% effective at preventing mild or moderate illness caused by the variant first discovered in South Africa. As a result, the South African government has decided to no longer use the AstraZeneca vaccine and is instead relying on other ones.
As of late March, the AstraZeneca COVID-19 vaccine has been given authorization in 86 countries – first by the U.K. in December and then by the European Union, Canada, India, Argentina, the Dominican Republic, El Salvador, Mexico and Morocco in January. In February, the World Health Organization granted the vaccine emergency use listing, making the vaccine available in low- and middle-income countries.
So far, over 17 million doses have been administered in the European Union and the U.K., but none yet in the U.S.
4. When Might the U.S. Authorize the Vaccine?
Although the AstraZeneca vaccine has been approved for use in many countries, the company has not yet applied for emergency use authorization in the U.S. AstraZeneca is expected to do so in March or early April, and if the Food and Drug Administration gives the vaccine the green light, vaccines could be shipping out by mid- to late April in the U.S. It is hoped that U.S. authorization will bolster global confidence in the vaccine.
Maureen Ferran is an Associate Professor of Biology, Rochester Institute of Technology. Ferran earned her M.S. and Ph.D in Genetics from the University of Connecticut, where she studied how viruses evade the host immune response. She then went to the Laboratory of Viral Genetics within the National Institute of Allergy and Infectious Disease at the National Institutes of Health, where she studied Human Papillomavirus. Maureen Ferran is an associate professor at the Rochester Institute of Technology in Rochester NY, where she teaches several courses including Virology, Infectious Disease: Impact on Society and Culture, and Eukaryotic Gene Regulation and Disease. Her research lab focuses on the development of viruses as a cancer therapy and the use of imaging agents to detect and target cancer.