There’s been a gross deal of speculation about an (even bigger) Coronavirus outbreak, one that could cost countless lives and send the world economy into tailspin. It makes jolly good fodder for the internet activists of our time, but how accurate is the claim?
That depends. The folks over at Global Financial Data put together some nice info looking at the 1918 Spanish Flu pandemic, which killed tens of millions of people. The first graph shows the various peaks of the outbreak those years ago:

Next we have a trace of the stock market:

As you can see, the market was not visibly impaired by the rise of the flu, although the period also encompassed part of World War I. After the nominal end of the flu wave, which was relatively close to the finish of the First World War, the market experienced a period of handsome growth.
The applicability of the 1918 situation to today, or vice a versa, remains dubious, and yet it suggests that hysteria may not be the proper answer.