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.
The pandemic rages as the world waits for COVID-19 vaccines.
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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?
Vaccine development is usually a long process. The coronavirus pandemic is forcing researchers to innovate and test potential vaccines faster than ever before.