The indigenous people were exposed to many diseases, not just smallpox:
>...Numerous diseases were brought to North America, including bubonic plague, chickenpox, cholera, the common cold, diphtheria, influenza, malaria, measles, scarlet fever, sexually transmitted diseases, typhoid, typhus, tuberculosis, and pertussis (whooping cough).[2][3][4] Each of these brought destruction through sweeping epidemics, involving disability, illness, and extensive deaths
>...it wiped out something like 75% of the indigenous population of the americas.
It's hard to give a precise estimate of how many deaths occurred. Some say it was much higher than 75%. For example:
>...Between 1492 and 1650 the Native American population may have declined by as much as 90% as the result of virgin-soil epidemics (outbreaks among populations that have not previously encountered the disease), compound epidemics, crop failures and food shortages.
Yep, when they shipped us off to the Middle East in '03 they gave us the smallpox vaccination even if you had it as a kid because, well, WMDs.
Don't think I had it as a kid since I was born in '71 and that's around the time they were phasing it out -- or at least didn't have the vaccination scar before '03.
Weaponized smallpox almost certainly exists. It escaped a Soviet lab in the 70s and other countries including the US worked on it.
Smallpox is uniquely deadly... it wiped out something like 75% of the indigenous population of the americas.