You can't look at people and tell if they have HIV/AIDS

ALTHOUGH the national anti-stigma campaign featuring healthy-looking persons living with HIV has had the reverse effect on some Jamaicans, one of the individuals featured in the series of television advertisements says the impact would have been worse had the decision been taken to use people who show physical signs of the disease.

http://www.jamaicaobserver.com/news/You-can-t-look-at-people-and-tell-if-they-have-HIV-AIDS-_15526362