When Pfizer announced its late-stage novel coronavirus vaccine candidate was 90 percent effective on Monday, stock markets soared, critics started taking shots on Twitter, and right-wing conspiracy theories about the timing of the announcement—less than 48 hours after Joe Biden claimed the presidency—quickly proliferated.
The public-health implications are massive. Pfizer expects to request emergency-use authorization from the U.S. Food and Drug Administration before the end of the month. If that happens, the company could begin shipping doses to front-line health workers and vulnerable populations such as nursing-home residents. Still, experts warned against prematurely declaring victory over the novel coronavirus given just how unproven the technology at play here is.