According to the 1st edition Advanced Dungeons and Dragons DMG, every month in the absence of medical risk factors or exposures, each D&D character has a 2% chance of developing an illness or a 3% chance of developing a "parasital infestation" whatever the hell that means. Furthermore there is a non-insignificant chance of most diseases rolled being fatal. You also make additional disease checks following an exposure and the probability jumps by 10% if there is a known exposure.

Many of the systems which can be affected by disease are sort of suspect (i.e. "mucous membranes") as discrete categories.

I'm kind of over-simplifying here to calculate quickly, out of 16 possible illnesses, the average probability of rolling a fatal disease is 21.875%. So the monthly probability of developing a fatal illness is 0.02*0.21875=0.004375 or ~0.4%.

Consider, in contrast, how the probability of rolling a critical hit requiring double 20s would be equal to .05*.05=0.0025 or ~0.3%. In other words if your character has a disease exposure while fighting a random encounter, it's probably more likely that he develops a fatal disease than that he scores a critical hit requiring 2 20s.

In the first place, consider that a human player character with a 30 year career therefore has a 30*12 rolls of the dice to randomly get sick, or 360 rolls, so at a 5% probability we expect around 18 illnesses per career.

But secondly, consider how elves and dwarves have enormous lifespans. They roll the dice hundreds if not thousands of times. By the numbers they should be getting extreme amounts of diseases.

Is this why dwarves are dirty and smelly, and why elves seek isolation so aggressively?

Which doesn't seem all that far off from medieval life. Have your kids early, because you won't live past 30.

That's also not including the mortality rate for childbirth. That being said, the actual life expectancy wasn't as poor as most numbers make it up to be. Remember, statistcs are easy to twist and misread.

Good point. Death at birth does tend to skew the average age at death.

That seems like one of those things which he just threw in to fuck with the players. Is it realistic? Well...

Probably. Diseases picked up on the campaign trail killed far more soldiers than enemy swords and arrows ever did, and this has only changed since around the 1940s. Even then, I'd say disease still put more soldiers out of action than the enemy until about the 1990s.

Of course, a band of adventurers is likely to fare better than an army. Most of an army can be fairly fastidious and good about keeping their health up, and one jackass who likes to slink off and fuck cheap whores naked in a bog and slip back without washing off is going to catch something dreadful and give it to everybody else. Adventuring parties are likely to not have That Guy, but they're still living in a time wherein disease vectors are largely unknown and the ways to prevent yourself from catching the Red Ring of Death are half superstitious bollocks.


But honestly, it's not very fun. The Lord of the Rings wouldn't have been very interesting if it devoted a chapter to everybody catching pneumonia after their misadventures on Caradhras and spent two months shacked up in the woods with Gimli (Dwarven CON bonus) and Gandalf (WIZARDRY!) nursemaiding them back to health. The only time LotR got into illnesses was the time it was magically inflicted.


Really, it's just a matter of what's going to be fun at your table, and what isn't. If your players actually enjoy rolling for punitive fuck-yous, go for it, but I wouldn't make them. I just assume that, as part of the adventuring elite, they have at their disposal ways and means which render them immune to normal, everyday woes like catching crabs from whoring in town or the creeping crud from trekking through the bog, just like I don't make them roll a Reflex Save vs. stubbing their toes in the dark when they wake up to take a midnight piss in an unfamiliar inn.

Is it wrong that 'Elven STDs' jumped to mind when we saw the header for the thread?

Elves are just better, you should know that. The only STD that shtupping elves carries a risk of is called "pregnancy." And there's a guaranteed solution for that: it's called homosexuality, yay! (Alternative, Cure Disease removes parasites. Biologically speaking, a fetus is a parasite; QED...)