The vaccines authorized for emergency use do not contain the live virus that causes COVID-19, so it cannot make you sick with COVID-19. The vaccines are made with mRNA technology which works by teaching your immune system how to recognize and fight the virus that causes COVID-19.  Sometimes when this happens, the process can cause symptoms like a fever or muscle aches. This is normal and, most importantly, proof that the vaccine is working, building immunity to COVID-19.

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