Vaccine development was one of the few shining lights during a dark past ten months. After a remarkably rapid design and trial period, pharmaceutical companies Moderna and Pfizer announced efficacy percentages in the high 90s. A tremendous achievement, but even an efficacy of 95% means five percent of vaccinated people are susceptible to Covid-19. Some vaccines, like the Oxford-Astrazeneca and Chinese vaccines, have efficacy around 90 or even 80%.

Assuming efficacy numbers hold true, many millions will still get infected after receiving a vaccine. Five percent of a global population approaching eight billion is upwards of 350 to 400 million people. Ten to twenty percent could be as many as 800 million to 1.6 billion people. For those people who were vaccinated that were later infected, what happened?

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