https://apnews.com/0c4ecadc0ca6dfd70ebead5173271fc7 > While a few have already hit the market, there are still dozens of coronavirus vaccines in development around the globe. > Some use tried-and-true technologies, other use novel approaches. The shots were all tested differently, and some were allowed to go into use even before they were rigorously tested. How well they work varies, with preliminary study results ranging from 50% effective to over 90%.