The black plague was so deadly because people were already in marginal health

I heard this theory, that a major reason the plague killed so much wasn’t so much due to the bacteria itself being extremely fatal but because people were already sickly from malnutrition and other diseases. Then again, if that were true then all the other plagues that hit pre industrial society would also have had 30-50% mortality rates.

If a westerner gets the plague now would it have mortality rates nearly as high (assuming no medical care)?

I think the people positing that theory may have forgotten the complete lack of germ theory and the widespread un-sanitary disposal of fecal matter.

Well, according to the below link, this is what it looks like to me:

Clearly, plague spreads faster and to more people in rural, agricultural, third world areas than more urban or suburban areas. From what I can glean from this site- and if I made a mistake please let me know- that if a person is in a first world country with reasonable access to medicine and prompt treatment, the plague has an 8-10% fatality rate. Without those things or without prompt treatment, the fatality rate goes up dramatically.

In third world countries with less access to medical care, the fatality rate is much higher.

So it seems to be not so much the health condition of the plague victim prior to infection that makes much of a difference (though age and health history do make a bit of a difference), but how quickly diagnoses can be made and how quickly and available known and current treatments are to that person.

Make sense?

People who are debilitated/malnourished can indeed be more susceptible to disease and more likely to die (a modern example is measles, which is much more deadly in those who are vitamin A-deficient).

As the OP noted, not all diseases are equally virulent in these groups. It may also be that plague in the Middle Ages involved a more dangerous strain than what we have today. Smallpox varied in severity over the years before being eradicated. Syphilis was reportedly extremely nasty in the past compared to now.

*""[W]hen syphilis was first definitely recorded in Europe in 1495, its pustules often covered the body from the head to the knees, caused flesh to fall from people’s faces, and led to death within a few months." The disease then was much more lethal than it is today. Diamond concludes,"*y 1546, the disease had evolved into the disease with the symptoms so well known to us today."[17] The epidemiology of this first syphilis epidemic shows that the disease was either new or a mutated form of an earlier disease"

My question is what happens if a westerner gets black plague w/o any medical care? Assume they are camping in the middle of nowhere and get it. They have food and water, but no medicine.

Does the fact that the westerner has a better immune system due to a diet high in vitamins, minerals and macronutrients, and the fact that their health is pretty decent to begin with (compared to people in pre-industrial societies) mean the death rate is lower, and possibly much lower, than 30-50%?

I don’t think we can give you the precise numbers you’re looking for. Plague, in all its forms, is pretty rare in the world, and even rarer in the US and other first and second world countries, and when it’s identified, it’s treated. So we don’t have a large control group of first world untreated people to look to. We only have about a dozen people a year, who are treated. And lots of them still die. The hypothesis is an interesting one, but completely unethical to research by withholding treatment, and we don’t have enough naturally undiagnosed cases to crunch the numbers post-mortem.

That’s today, not historically. Of course, that includes those in the third world, with health probably similar to those in plague ridden Europe.

But no, I don’t think I’d rely on a robust health status saving me from plague.

Frankly, it reminds me of the anti-vaxxer theory that improved sanitation and health status did away with measles, and not vaccination. Nice theory, but it’s not up to me to disprove it, it’s up to them to prove it. (They can’t, because it’s not true.)

According to the CDC between 1900 and 1941 the fatality rate of the bubonic plague in the US was 66%. That’s with medical care, but without antibiotics.

  • One of the reason the Black Plague was so feared was that it took those in the prime and best of health. It doesn’t seem to have hit the young or elderly or those already sickly harder than the 20yo youth in the best of health and condition.

  • Westerners, those descended from Europeans, today are supposed to have some measure of genetic protection against the Black Plague. It is speculated that this protection also helped to some extend in making the AIDS epidemic less severe. So westernes today, all things being the same, would probably have a lower mortality rate.

Please. Plague of Color. Let’s not be committing any micro-aggressions here.

Would the survivors’ children be Plague-Americans?

Likewise, the flu pandemic of the 1918 affected those with the strongest immune systems the most. So this is probably one of those hypotheses that sounds good when you propose it, but doesn’t really stand up to scrutiny.

This just in:

It’s a bacterial disease, so antibiotics can definitely help. As long as the doctor (or the patient) doesn’t assume it’s some kind of virus going around. No matter how healthy you are, avoid the plague. Like the plague?

Oh, look. There’s been an outbreak of pneumonic plague in Madagascar. It’s more easily spread…

A healthy lifestyle is a great idea–but won’t save you from this one, either.

One theory is that the plague is less deadly today because the more virulent strains went extinct during the Black Plague, having killed most of those infected quickly and thus not having as much opportunity to spread as a less virulent strain. This might account for some of the difference in mortality as well.

As I understand it, all infectious diseases should grow less deadly over the centuries. From a bacteria’s perspective, it’s bad to be too deadly. If you kill everyone that you infect right away, you don’t have time to spread to new people. What you want to do is have your victim linger for months or years, spreading germs during that time. So from a Darwinian perspective, less deadly bacteria win over more deadly ones.


I don’t think anyplace on Earth, except perhaps smack in the middle of a warzone has health as bad that of Middle Age Europe.

I don’t know, but i know a song about it