You might wonder at the title here. It is intentional. The people of the world are often unaware of how far we have risen from the era when plagues and pandemics would strike and wipe out forward progress, families, and hope from the world populations. Black Death, Bubonic Plague, Ebola, and Spanish Flu have killed multi millions of people. And, with human population numbers increasing, and the density of humans per mile increasing, a major event that will once again adjust the numbers of humans, as well as strike fear into the heart of people who have no defense against the villain, will absolutely happen. Just when, how badly, and why, I don't know.
Such horrors have been fictionalized, in small scale as in Daniel Defoe's plague year journal, which was fiction, though based upon real events, or upon a major scale, such as found in the Stand by Stephen King, or Michael Crichton. Whatever humans do we cannot escape the possible outbreak of disease, or plague. We don't control all of our risk areas.
But some authors study plague, pandemics, and place them in a context of numbers and world history events. Plagues affected great empires, and weakened them allowing for rebellions to succeed. Pandemics caused wars of limited nature to be far worse than we could ever have imagined. The Spanish flu left few American families untouched, and the terror of World War 1 was made worse by such a pandemic beast.
On occasion I've been accused of being to pessimistic about the future. This isn't one of those times. This is a time where I point to what has happened, and how some research it, and others use fiction to explore it. One can live a perfectly normal life without knowing about all of this, but, who knows who might be inspired to fight it all, and perhaps improve the species' chance in the future?