Was the bubonic plague the worst epidemic?

Kyle Harper, author of 'Plagues Upon the Earth', compares the COVID-19 pandemic to other disease outbreaks throughout history...

Kyle - Well, it depends on what you mean by worst. And if you mean the worst infectious disease in terms of total mortality, it's probably not actually plague, but it's something like tuberculosis or malaria that cause more suffering and death than probably any other infectious diseases.

If you mean the worst infectious disease in terms of pain and suffering, it'd be very hard to say. You'd probably want to put syphilis on the list before it was treatable. It was a pretty miserable scourge on human societies and tertiary syphilis, very advanced syphilis, was so bad they used to treat it with malaria.

In fact, a scientist won a Nobel Prize for coming up with malaria therapy. Luckily antibiotics were discovered soon after. If you're just talking about what epidemics cause the most extreme, sudden mortality events, then it would either be plague or influenza. The 1918-19 influenza probably killed more people, but also global population was larger than even the great plague pandemics of the past.

But if you're talking about the proportion of a population that succumbed to a disease on a short timeframe then it probably is bubonic plague, which is a bacterial disease caused by Yersinia pestis, that's a very strange germ. It's really a rodent disease that is transmitted by fleas, although it can be transmitted directly by droplets between humans as well. But it causes the Black Death. It causes plague outbreaks in Europe, down to the 17th and even early 18th century. In parts of the Mediterranean, near east, even later than that. And it probably does more damage than any other disease. It's a really kind of mind-boggling phenomenon to try and even imagine.

The Black Death we know killed half the population in very significant areas. And you just sort of compare that to COVID-19 and think of the disruption that it's caused our society, which of course is very different. Our society depends on the basic control of infectious disease, of course.

But even so I think it is, as someone who thinks about past societies, it's such a challenge to imagine what it must have really been like to live in a city or a country where in the space of a year, half the people were simply gone.