There is nothing unusual about devastating epidemics.
It is one of those things like earthquakes, volcanic eruptions or tsunamis that are well known and bound to happen at some point and which have never went away. The 1918 Spanish Flu pandemic killed 50 million people around the world and around 675,000 Americans. Influenza killed nearly as many American soldiers in World War I as those who died in combat. 70,000 Americans died from influenza in 1957/1958 and 34,000 died in 1968/1969.
Maybe the Wuhan coronavirus will fizzle out like SARS, Ebola, bird flu or swine flu before it. There is no reason to believe that epidemics are a thing of the past though because we have developed vaccines for the common flu. If you added up all the Americans who died from all causes in World War I, World War II, Korea, Vietnam, Iraq and Afghanistan, a century of war on foreign battlefields still wouldn’t have been as deadly as the Spanish Flu was a century ago.
Bad things do eventually happen on a long enough time scale. Disease is also now a greater threat than war between the great powers. China and the United States would much rather trade and grow wealthy than go to war over almost any conceivable issue. The same was true in the past. Plague came to Europe in the first wave through trade routes in the eastern Mediterranean and the second time via the Silk Road. There hasn’t been a major airborne pandemic in the age of global commercial air travel. It is only a matter of time though.
Note: In the age of mass shootings, the possibility of a rogue eco-terrorist motivated by some cause like climate change releasing a deadly genetically engineered virus is also worth thinking about. It was the plot of the movie 12 Monkeys in the 1990s.