At the close of the twentieth century, medical science could look back with a great deal of satisfaction on many outstanding achievements and successes in the control of communicable diseases. Confidence in controlling the bulk of communicable disease threats rose with the availability and effectiveness of an increasing number of preventive vaccines and therapeutic advances.

However, as the century was coming to a close there arose one of the most menacing of communicable diseases. This relentless plague, which would progressively and inexorably expand its reach into the human population, was HIV/AIDS. By the end of the century, South Africa came to carry the heaviest burden of the pandemic, with the largest number of people living with the infection in the world and driving the largest HIV/AIDS treatment programme globally. Close to one in five adults (15 to 49 years of age) are infected with the virus. The figure is even more frightening in some sections of the population, especially young women in KwaZulu-Natal, where the prevalence of infection is as high as one in three.

Some 40 years after the discovery of the virus the cumulative global death toll from HIV/AIDS, as of the end of 2021, stood at 40.1 million.

Given South Africa's disease burden, it is not surprising, therefore, that the HIV/AIDS research unit is the largest research unit in the NICD. It has contributed enormously to the understanding of the virus and the disease, as well as making important contributions to research efforts into developing the elusive protective vaccine. Unfortunately, political interference, yet again, had a turn in meddling in the activities of this unit, and in so doing wasted valuable resources, energy and time while the epidemic was advancing rapidly in the population. Support for dissident anti-science was fortunately temporary, but at the time it became a worrying reputational embarrassment.

THE EARLY DAYS OF THE PANDEMIC

The saga of HIV/AIDS commenced rather unobtrusively in Los Angeles in the autumn of 1980. An alert physician, Michael Gottlieb, and his colleagues were intrigued by the unusual presentation of a cluster of five young male patients under their care who were all diagnosed with a very uncommon form of pneumonia due to a parasite called Pneumocystis carinii. Previously, this infection had been seen almost exclusively in patients whose immune systems had been severely depressed, either by disease or drugs used in transplant recipients or patients on cancer therapy.