Disease in history

[anthriel]

This topic was split off from the "Caring about Africa" thread. Anthy, please feel free to change the title as you please. I'm not very verbally agile today.

—Primula Baggins, for the Marshals

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There are a lot of infectious diseases that take out people all the time. "Old" diseases, diseases that well-raised people don't worry about anymore, the ones that those of us wealthy and fortunate enough to live in high profile societies with good plumbing and medical care don't even think about.

Cholera is wiping out people in Haiti right now. Doesn't that sound like an archaic old disease? Easily preventable by good water treatment practices, easily treatable by rehydration and antibiotics.

http://www.bbc.co.uk/news/world-latin-america-11690333


I read an article recently that proposed that cancer was a "man made" disease, and used as the proof the absence of evidence of cancer in Egyptian mummies. Apparently the logic was that the Egyptians lived in something of a purer time, before man created the current scourge of cancer.

http://www.msnbc.msn.com/id/39687039/

Of course, the average age of death for those folks was less than 40. Most people even now aren't diagnosed with cancer before 40. So assuming that an autopsy on a 2000 year old mummy can tell you whether the person died of cancer (I wonder about that... how many internal organs are truly preserved in a mummy?), most of those people simply didn't live long enough to get cancer, even if they had lived in our jacked-up world of today. A lot of them probably died of infectious diseases.

I think people think we have won, with the infectious diseases thing. Not so much.

[Griffon64]

Anthy - I do seem to recall that they have found at least one mummy with a bone tumor - a link I found quickly ( http://africascience.blogspot.com/2007/ ... -pain.html ) as well as Egyptian texts referring to cancer treatments. I think you're right when you think that given the average lifespan in those times, many cancers may just not have had time to develop, yet. Not that we understand what causes cancer very well yet, do we? Environment could well have something to do with it, but people don't know, yet. Our medical knowledge are really still in a sort of infancy, despite huge leaps and bounds in advancement we have taken.

And people still die of malaria and cholera ... it happened in South Africa, too. There are parts of South Africa you don't visit without taking a malaria tablet, unless you are looking for trouble.

[Primula Baggins]

Cancer is a big collection of different diseases, and each probably has its own set of causes. There's no doubt that there are environmental causes for some cancers, but not all. That's one reason a cure for cancer will never be found. The problem fragments into tiny pieces as soon as you look at it.

Some cancers are already essentially curable, if you're lucky. Others are a long way from that. And prevention is another tough nut to crack.

Anthy, I'm in the middle of editing an enormous text on infectious diseases of dogs and cats, and it's fascinating how incidence varies throughout the world—and also how many "old" diseases are still endemic. Plague, for example. People can usually be saved if it's recognized in time, but often it's not, especially if the victim has traveled to a part of the world where it isn't endemic.

It's also more than a little scary how many serious diseases people can catch from their dogs or cats, especially if the pets are allowed to wander freely outside in areas where there's wildlife.

[anthriel]

Cancer is a big collection of different diseases, and each probably has its own set of causes.

Very true! Instead of trying to solve one puzzle, it's like trying to simulateously solve hundred of puzzles.

And people still die of malaria and cholera ... it happened in South Africa, too. There are parts of South Africa you don't visit without taking a malaria tablet, unless you are looking for trouble.

South Africa really has some tough infectious disease battles, actually. Multiple drug resistant tuberculosis is really a big problem there. And now India has trouble with bacteria which have learned to be resistant to a different class of drugs, the carbapenems. We have seen these isolates here, but India really has an acute problem right now.

So we have bugs getting smarter, as in these which are multi-drug resistant. Then we have bugs that are just still "around" (like plague... had a two cases of that through our lab lately!) and are just waiting for their opportunity. Plague flourishes where rats flourish. Cholera loves it when drinking water is easily contaminated with fecal matter. Malaria is just waiting for the right mosquito.

THEN we have bugs which are possibly linked to... yep, cancer. There is an increasing body of thought that many cancers (mostly, I think, liver cancers) are either caused or activated by certain viral infections. Cool, right?

I guess I just light up on this kind of thing because I think so many people die every single day of things that so many of us don't have to worry about... 'cause we think it's gone. Just 'cause we don't have a lot of dengue fever or malaria in the USA doesn't mean it's not taking lives elsewhere. The plague is not some dusty old 13th century European boogeyman... it's still real!

[WampusCat]

It's also more than a little scary how many serious diseases people can catch from their dogs or cats, especially if the pets are allowed to wander freely outside in areas where there's wildlife.

I'll probably regret it, but could you say a little more about this? The only ones I can think of from cats are toxoplasmosis and rabies.

I just got back from taking Strider to the vet for a nasty, abscessed bite wound. Fortunately his rabies shots were up to date.

[Primula Baggins]

Wampus, I shouldn't have tossed that off; I'm on Chapter 47 of 100 and there's a lot of material, probably 6,000 manuscript pages by the time I'm done (January?). But cats are generally less of a problem than dogs (other than toxoplasmosis).

Plague is a problem and people do catch it from infected cats, but plague is not endemic where you are. Tularemia is serious but really rare, and cases that can be traced to cat scratches are more rare still, though it has happened. Lyme disease doesn't appear to be caught from pets; if pets and humans are sick at the same time, it's usually because they had the same exposure to ticks. Leptospirosis can pass from dogs to people, but cats don't seem to do that.

That's what I've read recently.

[WampusCat]

Thanks!

[elfshadow]

I find it hard to believe that cancer didn't exist at all in Egyptian times. Our DNA is being mutated every day, without any environmental stimuli, only most of the time the effects of these mutations are small enough to be unnoticed. Occasionally, they might lead to cancer. Cancer is more prevalent in older people because they have lived long enough that there is a bigger chance one of these mutations will lead to cancer. This is why, in cancer studies, we usually distinguish between cancer at a young age and cancer at an old age. Cancer at a young age is most likely caused by either a genetic mutation or environmental causes.

I think that the prevalence of cancer, as with many diseases, has increased so rapidly because we are able to treat it now. When a person with a genetic mutation gets cancer and survives, they can pass on the mutation to their offspring. Thousands of years ago, people with these mutations may not have lived long enough to pass on the gene. Of course, only a small percentage of cancer is due to a specific genetic mutation. Certainly there are environmental stimuli that can lead to cancer-causing mutations that societies like the Egyptians didn't have. Still, I think that Griffy's explanation is the best one. When people don't normally live past the age of 35 or 40, their chance of cancer decreases simply because most forms of cancer take time to develop.

[Túrin Turambar]

I think that the prevalence of cancer, as with many diseases, has increased so rapidly because we are able to treat it now. When a person with a genetic mutation gets cancer and survives, they can pass on the mutation to their offspring.

True, but if people have already had children when they get the cancer (and cancer tends to become more likely with age) then the gene is passed on anyway.

Personally, I suspect that the major reason is that people don't die of other things as much. My grandfather died of a heart attack in 1963 at age 57, an extremely common scenario in those days. Now that we can treat high blood pressure and heart disease and a host of other illnesses people are now living long enough to die of cancer in larger numbers.

[axordil]

Be wary of average life expectancies and ages reached in antiquity. Average life expectancies figure in infant mortality, so they look low, when the proportion of the adult population that reached 60 or 70 was probably not too different than that of the early 20th century.

[yovargas]

How many ancient mummies do we really have to search for tumors and whatnot? Surely we don't have thousands of mummified corpses around to study and dissect, do we?

[Dave_LF]

Be wary of average life expectancies and ages reached in antiquity. Average life expectancies figure in infant mortality, so they look low, when the proportion of the adult population that reached 60 or 70 was probably not too different than that of the early 20th century.

Yup. Even in feudal England, which had some of the harshest, most unsanitary living conditions you can think of, evidence shows that most people who survived childhood expected to live to about 50 (depending whom you ask), and people living into their 70s were far from uncommon.

[elfshadow]

I think that the prevalence of cancer, as with many diseases, has increased so rapidly because we are able to treat it now. When a person with a genetic mutation gets cancer and survives, they can pass on the mutation to their offspring.

True, but if people have already had children when they get the cancer (and cancer tends to become more likely with age) then the gene is passed on anyway.

Yes, that is true, although genetic cancers do tend to occur much earlier in life than non-genetic cancers. It is more likely for someone with a genetic mutation for cancer to die before childbearing age than for a person without the mutation. Also, some genetic mutations that cause cancer significantly decrease fertility.


Ax, I still expect that the percentage of people who lived into their 60s and 70s two thousand years ago was smaller than it is today, due to wars and diseases and famine and dehydration, and other factors that are much mitigated in the present day (particularly in the developed world).

[Frelga]

Women tended to die younger than men, as childbirh was a major cause of mortality. Violence and wars evened things somewhat for men. Otherwise, people either died very young, in chidhood if not infancy, or they lived to a ripe old age. The 35 year average is a statistical average - I would guess that 30s was probably the least likely age for someone to die.

[axordil]

Yovargas--

We used to have a lot more mummies. They were so common in Egypt under early British occupation that they were used as fuel for steam locomotives.

Not all of those are going to be preserved well enough for meaningful postmortems, of course.

All--

I don't doubt fewer people made it to three score and ten--but the choice of that number in the Bible isn't random or rosy-hued. Enough people lived that long to make it the "natural" assumed lifespan for societies from antiquity to the Industrial Revolution.

Some of them certainly came down with cancer. The chances of doing any useful epidemiology seems to me very low, however.

[Nin]

The chances of a diagnosis too... how did people know that they had cancer when it's a disease which you often don't see? Most inward diseases are not known before the 18th century.

Anyway, this is perfectly right:

Otherwise, people either died very young, in chidhood if not infancy, or they lived to a ripe old age. The 35 year average is a statistical average - I would guess that 30s was probably the least likely age for someone to die.

Demographic was compulsory in my history lectures... I must dig out some memories.

[axordil]

To be fair, though, Nin, some cancers are visible--skin cancer obviously, but internal tumors can break through the skin as well (ulcerating I think they're called).

Ick. What was the actual topic here again?

[Primula Baggins]

The pain of cancer was well known before the hidden tumors were.

[River]

Some of the other symptoms were no doubt recognized as well - appetite loss, weight changes, weakness, and so on. And if a mass is big enough, you can feel it or even see a bulge.

But that doesn't mean anyone understood what they were looking at.

I personally am not convinced that cancer rates now are the same as they would have been in the pre-industrial era if people had lived as long and the disease been recognized. There's some pretty solid evidence linking modern toxins and some modern habits to increased cancer risks. Furthermore, there's no good, old epidemiological data. We're trying to define a curve with more than one but less than two points. It's a cute academic exercise, but we're not going to get anywhere.

As for infectious diseases, our dear old friends cholera and plague have all but disappeared from the developed world. Modern pest control and sanitation have worked wonders. But in broken places like Haiti and Zimbabwe, where you have lots of people living close together without any means of keeping the water supplies clean, cholera is almost inevitable. If we in the US found ourselves in that kind of situation, it would happen here too.

[Dave_LF]

Some of the other symptoms were no doubt recognized as well - appetite loss, weight changes, weakness, and so on. And if a mass is big enough, you can feel it or even see a bulge.

Even as far back as the Old Testament, there is talk of the Philistines being smitten with tumors after handling the Ark (IIRC). But I suppose there could be a translation issue there.