By some estimates, about 40 percent of the population of the United States will have been infected with the omicron variant of Covid-19 by the time the current wave fully subsides. The WHO estimates that half of Europe will have been infected as well. And nearly all of those infections will have occurred between mid-December and the beginning of February.

It’s hard to say for sure, but there’s good reason to think that never before have so many people been infected with an emerging virus in such a short timespan. For most of history, diseases traveled much slower, carried by travelers on boats or horses.

It took years for great historical plagues like the Black Death to spread across Europe and Asia. One of the biggest infectious disease-caused mass death events in history, the spread of smallpox and other European-originating diseases through the Americas, is estimated to have taken a few years to a decade.

But now, thanks to our far more interconnected world, an incredibly contagious virus required only about two months to go from when it was first detected — November 11 in Botswana — to when likely more than 2 billion people had been infected.

We are incredibly lucky that omicron seems to be milder than previous strains of Covid-19 and that both vaccinations and previous exposure have built up immune resistance. The massive spike in cases around the world — while badly taxing health care systems — hasn’t been matched by an equal spike in hospitalizations and deaths.

I think it’s hard to appreciate what a massive bullet we dodged: If omicron had been substantially more deadly, there is very little we could have done to stop the death toll.

Read the full article about the Omicron variant by Kelsey Piper at Vox.