19 vaccines have received emergency use authorization from the relevant regulatory authorities in at least one country.However, one issue has continued to agitate the minds of the general public and health experts alike: What side effects might these vaccines cause, how often, and under what circumstances?Commonly reported side effects across the different types of vaccines include fevers, fatigue, headaches, and body aches.Serious side effects are extremely rare, and national and international health agencies continue to collect and monitor reports about any adverse reactions.However, as vaccination rollouts have progressed around the world, some people have pointed out a potential side effect that feeds into existing debates about the.