Ten years to be safe but they are long gone after twenty years and its been more than twenty years since there was any disease to vacinate against (except in lab). In other words, unless youve had small vacination in last two or three years, your not covered.
I have heard various things on this. I was vaccinated in 1947 when I was born, then at numerous times in the military, none of which "took" (1965-1975) meaning that I was still protected.
I was told that there was no more point in revaccinating, since once taken, you are protected.
I have no idea what the "official" line was or is, but none after the one I had when I was an infant "took".
Keep the Faith for Freedom
MAY GOD BLESS AND DEFEND THIS HONORABLE REPUBLIC
Greg
If I recall correctly, there was a thing called COW POX that milkmaids got. However they didn't get small pox. Isn't there an immune relationship between chicken and small poxen too? Can't we vaccinate against those diseases and acquire a similar immunity to small pox?
And unless the Swiss start sending some of those doses to the US, your old small pox vaccination will last until you catch it.