tl;dr: The Plague of 1541 may be the closest parallel to what is going on in the world today with the Covid-19 coronavirus.
In 1541, Hernando de Soto led the first European expedition to sail up the Mississippi River.
As part of the expedition, they left with 200 pigs, but even before they were out to sea for a week, 2 of the pigs developed the telltale signs of smallpox and were summarily thrown overboard.
Unfortunately, the plague continued to brew among the pigs, but because the Spanish had such a high immunity to smallpox, the Captain just ordered that the obviously infected be thrown overboard. By the time they reached Tampa Bay, Florida, on 15 May 1539, three weeks later, only 13 pigs remained on board, much less than expected.
Relieved to finally be onshore, the sailors did not adequately seal the quickly-built pig pen and somewhere between 4 and 8 pigs escaped into the wilderness.
Over the next few years, Hernando de Soto explored much of the southeastern region of North America, including much of the Mississippi River.
According to the book “1491: New Revelations of The Americas”,
Smallpox was a novel virus to the Native Americans. As such, it infected very close to 100% of them and may have had a fatality rate over 95%.
Because of this, De Soto reported back to Europe (paraphrased) that “The Mississippi is completely occupied. There is no room for colonization.” It was over 140 years later until the next set of European explorers traveled up it, and this is what they saw:
By some estimates, over 90, even as high as 95%, of all North American Indians may have succumbed to a mixture of Smallpox and Chickenpox carried over from both the Spaniards and their pigs in the next 5-10 years.
Thus, by the time Europeans once again revisited the Mississippi River in the late 1600s, the Native Americans the French and British encountered were not the highly civilized and organized city-states Hernando de Soto had encountered, but roaming tribes of a Post-Collapse pandemic survivors. Long lost (except for the Micmacs of Upstate New York) was the written word, most of their histories were in shambles, and the people themselves were forced into roaming with their prey just to have enough meager portions to survive the next Winter.
Lethal novel viruses — like smallpox is to the Native Americans and the Covid-19 coronavirus is to us all — usually infect 90%+ of the population and only run their course after it has spread to everyone who can be infected.
Please prepare today.