We didn't keep contracting mad cow disease until everyone who wasn't genetically immune to it died. I'm pretty sure we figured it out and killed loads of cattle to stop us getting it.

OK, but generations of people keep drinking themselves to death.

Generations of people lived with lead water pipes and asbestos roofs.

Within living memory we had cocaine in coke, heroin in cough remedies and were giving pregnant women thalidomide for morning sickness.

Western science is a modern thing, and even now many people don't believe it.