It's a sad day in South Africa. Reuben Sher, an immunologist who warned the country about AIDS in the 80s, has died.

Sher had traveled to the United States, where the bug had already taken a severe toll. Returning to South Africa, Sher told his countrymen of the danger, telling them a "biological holocaust" would soon come crashing down. He was ignored.

HIV Clinicians Society President Dr Francois Venter remembers Sher:

[He was] man who warned us all that HIV would decimate the country, was ignored, and was tragically proved right.

He was without a doubt the first person in the scientific and medical community who tackled AIDS head on. He became Mr AIDS, everyone was seeking his opinion and he was often in the media. He was not scared to speak out even if it was politically sensitive.

When Sher began his crusade, two South Africans had already died of AIDS-related causes. There are now an estimated 1,000 deaths a day.