E ric Feigl-Ding picked up his phone on the first ring. “Busy,” he said, when asked how things were going. He had just finished up an “epic, long” social media thread, he added—one of hundreds he’s posted about society’s ongoing battle with the coronavirus. “There’s so many different debates in the world of masking and herd immunity and reinfection,” he explained, among other dimensions of the pandemic. “We at FAS, we’ve been kind of monitoring all the debates and how we’re seeing signals in which the data goes one way, the debate goes the other,” he said, referring to his work with the Federation of American Scientists , a nonprofit policy think tank. He rattled off a rapid-fire sampler of hot-button COVID-19 topics: the growing anti-vaxxer movement, SARS-CoV-2 reinfection and antibodies, the body of research suggesting masks could decrease viral load, along with a quick mention of the debate among experts about what airborne means. This whirlwind tour through viral COVID-19 themes felt like the conversational equivalent of Feigl-Ding’s Twitter account, which has grown by orders of magnitude since the dawn of the pandemic. The Harvard-trained scientist and 2018 Congressional aspirant posts dozens of times daily, often in the form of long, numbered threads. He’s fond of emojis, caps lock, and bombastic phrases. The first words of his very first viral tweet were “HOLY MOTHER OF GOD.” Made in January, weeks before the massive shutdowns that brought U.S. society to a halt, that exclamation preceded his observation that the “R0” (pronounced “R-naught”) of the novel coronavirus—a mathematical measure of a disease’s reproduction rate—was 3.8. That figure had been proposed in a scientific paper, posted online ahead of peer review, that Feigl-Ding called “thermonuclear pandemic level bad.” Further in that same Twitter thread, he claimed that the novel coronavirus could spread nearly eight times faster than SARS. The thread was widely criticized by infectious-disease experts and science journalists as needlessly fear-mongering and misleading, and the researchers behind the preprint had already tweeted that they’d lowered their estimate to an R0 of 2.5, meaning that Feigl-Ding’s SARS figure was incorrect. (Because R0 is an average measure of a virus’s transmissibility, estimates vary widely based on factors like local policy and population density ; as a result, researchers have suggested that other variables may be of more use.) He soon deleted the tweet—but his influence has only grown. At the beginning of the pandemic, before he began sounding the alarm on COVID-19’s seriousness, Feigl-Ding had around 2,000 followers. That number has since swelled to more than a quarter million, as Twitter users and the mainstream media turn to Feigl-Ding as an expert source, often pointing to his pedigree as a Harvard-trained epidemiologist Read More …