Remembering Nelson Mandela’s meeting with antiviral pioneer and Nobel laureate David Baltimore

David Baltimore came to the University of the Witwatersrand in 2007 to give a lecture on the origins of HIV. He was the ideal person to do so. A virologist of global distinction, he had at the age of 37 jointly received the 1975 Nobel Prize in Physiology or Medicine for reverse transcriptase (the mechanism by which retroviruses infect cells) and built a career of breakthrough achievements in biology. 

Baltimore, president of the California Institute of Technology (Caltech) at the time, gave a breathtaking lecture under the banner of the Nelson Mandela Science Lecture, funded by the Ford Foundation.

How the lecture came to be is largely a story about Mandela’s regret about not doing enough to combat HIV/Aids. After he stepped down in 1999 as South Africa’s president, his successor, Thabo Mbeki, sent South Africa backwards in mismanaging the unfolding HIV/Aids epidemic, from which the country has never quite recovered.

Refusing to embrace the benefits of modern science and the scientific method, Mbeki made up his own bizarre theories to justify his moral failure to finance the rollout of antiviral therapies. A Harvard University study estimated that 330,000 died unnecessarily.

After he left office in 1999, Mandela committed his Nelson Mandela Foundation to quietly hold the Mbeki government to account for its HIV/Aids policies. Personal diplomacy was preferred over public confrontation.

Zackie Achmat and the Treatment Action Campaign (TAC) had built a powerful citizen-science movement and adroitly used the law to compel the Mbeki government to roll out antiretroviral therapies to the communities living with HIV/Aids. For Mandela, it was personal. His eldest son died of Aids. He added his voice, but there came a time when Mbeki no longer took his calls.

Just before the lecture, I took David Baltimore to the offices of the Nelson Mandela Foundation to meet the great man. The former president was frail and remained in his chair throughout the meeting, a blanket covering his lap.

Caroline Graham, the co-organiser of the lecture and who published a piece in the Huffington Post about our meeting, accompanied us. We had 30 minutes with him.

David Baltimore explained to Mr Mandela, in a language so precise as only he could, that there was no vaccine and that an aggressive rollout of antiretrovirals, tough management of needlestick use and a high visibility public campaign for safe sex were key.

After 25 minutes, Zelda La Grange, Mr Mandela’s aide, signalled to me that our time was up, that we had exhausted his attention span. He said to me with some sadness that he was confined to a wheelchair and that he was sorry we saw him in such a situation.

As we left, his eyes lit up and, ever the political activist, said if governments do not do the right thing, including governments run by the African National Congress (ANC), we must “take the fight to them”. The next time I would be in his presence was at his funeral in the Eastern Cape.

We went on to Wits at noon for the lecture. As Baltimore rose to speak, students in a protest rattled the doors at the back of the Great Hall and threatened to disrupt the lecture. They were protesting against the university’s decision to raise fees, expressing their displeasure by emptying garbage out of bins and interrupting the lecture, but nothing violent.

Baltimore was undeterred. Inside the Great Hall, a student yelled to Baltimore: “You’re my hero! You rock!” Baltimore laughed. A science student asked: “How does one target the action of reverse transcription?”

The answer from Baltimore was: “Micro RNA is a very exciting new discovery of one approach. Micro RNA (miRNA) are tiny lengths of RNA, containing no genes, which regulate gene expression directly. The miRNA are complementary to messenger RNA or mRNA, which carries the code for protein production and acts to dampen gene expression. In other words, it is an off-switch.”

At the time, Baltimore was building genes to target the enzyme, the identification of which earned him his Nobel Prize.

After his lecture, Baltimore went on to visit the president of Rwanda, Paul Kagame. He was stunned by the investments Rwanda had made in Aids research. “Rwanda is the leader in Aids research. Rwanda is special. They are building a country on the back of genocide. They are committed to do the right thing. They have the best system in the world for monitoring Aids treatment, built and run by them with their own software,” he said.

David Baltimore died on 6 September 2025 at his Woods Hole home in Massachusetts. He will be greatly missed in the world of science and beyond. DM

Dr Wilmot James is a Professor and Senior Advisor to the Pandemic Centre at the School of Public Health, Brown University, Providence, Rhode Island. He is the co-editor of Nelson Mandela in His Own Words (Boston: Little, Brown and Company, 2003 and 2017) and South Africa’s Nobel Laureates (Johannesburg, Jonathan Ball, 2005).