One thing I’m not clear about is why smallpox inoculation, also called variolation, did not cause as much smallpox as natural infection vectors. I understand that pus from pox pustules was used in some cases, and in other cases pustule scabs were ground up and the dust blown up the patient’s nose.

In the latter method I could imagine (without really knowing what I’m talking about) that mostly “dead” virus particles were involved, able to invoke an immune response without much risk of killing the patient.

But in the former? I would suppose oozing pustules contained plenty of live virus. If that’s the case, I don’t understand why inoculation didn’t mostly cause full-blown smallpox.

I mean obviously, it often didn’t, and people in Asia and Africa had known this for centuries, but the explanation is a mystery to me. Do you have any insight?