United States, 1988
Salon.com has this great slide show of HIV posters from different decades and countries. I especially love looking at social marketing from other time periods. The poster above, for example, says the "AIDS virus" whereas now, most scientists would say "the virus that causes AIDS" which is HIV.
Trinidad and Tobago
This last poster reminds me of vintage STI posters from the WWII era in that it uses the female body to represent the disease, although at least it is equal opportunity in that it also shows a man in the same form.