The Flu Virus

Oh come on now, I’m sure you’re saying. The flu virus here in a list of the most lethal microbes?

Sure, every year during what’s called "the flu season" tens of thousands of people get the flu. Despite feeling all achy and lousy for several days, most people eventually beat the virus and recover just fine.

But that’s not how it went during the 1918 flu season. That year, World War I was raging so the effects of the flu virus sort of got overshadowed by the bigger, more obvious effects of bullets and bombs.

However, in 1918 the flu virus killed at least 675,000 American people. Worldwide, it killed at least 21,000,000 people. These are low estimates. Some research now suggests that the flu may have killed 40,000,000 to 50,000,000 people around the world that year.

Researchers still aren’t sure why the 1918 flu virus was so deadly. Victims of the flu that year died in a gruesome way, the virus causing so much fluid to build up in their lungs so rapidly that it was like drowning.

If higher estimates of how many people died from the 1918 flu are true, then the 1918 flu is the deadliest microbe ever in a single year. Thank goodness we haven’t seen a flu bug that deadly again—but will we someday?