>>11799517>tetanus is also caused by rust,This is actually a myth. I grew up believing the same and was even very worried when I stepped on a rusty nail as a child. In reality the environment is only marginally better for an anaerobe or its spores, and in some cases, probably worse. Tetanus occurs in soil largely because the spores are durable and organism itself comes from animal intestines.
Tetanus isn't necessarily lethal either, though it would definitely do some damage. However the vaccine itself carries the risk of damage. The risk:benefit is way against the vaccination.
Malaria is a curious case because there are a number of regional genetic adaptation. However, I suspect it's been cured many times (see eg Henry Lai at WSU, magnetic field based, and artemesinin). The reason it isn't cured is because the third world is a threat and must be controlled.
Polio is found in animal intestines as well, however I think it;s probably caused by immune suppression and organochloride pesticide exposure. Or being injected with it (eg Cutter incident). Iron lung was pretty rare.
