The side effects of new SARS-CoV-2 vaccines are a result of immune system activation. While uncomfortable, they are both normal and expected. They are a sign that the vaccine is working.
Because Pfizer-BioNTech and Moderna vaccines have been developed in record time, many wonder whether companies cut corners or compromised safety.
There are two new COVID-19 vaccines that appear to be more than 90% effective. But what are these vaccines, and how are they different from those used previously?
Interim analysis of trial data isn't unusual – but leaves us with many things we still need to find out.
Vaccine development is usually a long process. The coronavirus pandemic is forcing researchers to innovate and test potential vaccines faster than ever before.