re: #63 A hollow voice says Vaccinate the world!

Can’t speak for the 1918 flu, but yersinia pestis is a bacterium, not a virus, and I haven’t heard that it has changed significantly since we first encountered it. The main reason the epidemics of the 1350’s were so deadly was that the population was about the maximum that the economy (at 1350 tech levels) could support. A lot of people were borderline malnourished and they died quickly.

The book Biology of Plagues explores a fringe theory — and I don’t know if there is real evidence to support it — that it wasn’t the bubonic plague but instead some unknown Ebola-type virus.