Snipped from The Observer Magazine.

With AIDS being one of the most feared diseases of the world, I am always amazed at the few people who are willing to have unprotected sex with someone who is knowingly infected. And yes, I have actually known someone to do this, and the weirdest thing about it, they are still uninfected. So what is it about these certain rare few who can come into contact with this highly contagious pandemic and not get affected by this deadly virus?

Well, there has been a courageous journalist who traveled to Majengo, a slum in Nairobi, to interview famous sex workers who have been in “contact” with AIDS for decades without contracting the disease. What she found out about these women is that their way of life has a surprising affect on their ability to fight off the disease. Here is a small sample of what this incredible article has to say:

In the past 30 years Agnes has had unprotected sex with up to 2,000 infected men. Yet she and a small number of her fellow sex workers are still free from Aids. Stephanie Nolen travels to Majengo, a slum in Nairobi, to meet the extraordinary women and researchers who are changing the history of HIV…

What happened to her - or, more accurately, what didn’t happen to her - would prove to be one of the greatest discoveries in the 25-year battle with Aids. She would acquire, over the next two decades, a certain fame, in the world of virology and infectious disease, as one of those Nairobi prostitutes. But Agnes’s body would be slower to give up its secrets than anyone imagined…

Keith Fowke, a professor of medical microbiology at the University of Manitoba, who was then a student working under Frank Plummer in Nairobi, explained it like this. ‘We did the models and found that these women were not just really, really, really lucky - it was beyond the statistical chance of luck playing a role. We estimated that many of these women have had 500 to 2,000 sexual exposures to infected men when they weren’t using a condom.’ Surveys found that a quarter of the men who frequented sex workers in the area were HIV-positive …

Then Plummer and his team noticed something even more peculiar. The women’s likelihood of being infected with HIV/Aids was related to the length of time they had been doing sex work: the longer a woman had been selling sex in Majengo, the less likely she was to be infected. If she’d been doing it for five years and was still HIV-negative, the data suggested, then the odds were she was going to stay that way. These findings were so counterintuitive that Plummer and his team struggled to find anyone who would publish them. The phenomenon didn’t get major attention until two years later, when he described the resistant women at the International Aids Conference in Amsterdam in 1992…

Agnes has, in effect, a callus: the first time she was exposed to the virus, her body produced enough killer T cells to fight it off. This part isn’t unique - the body of every person who is exposed to HIV mounts some level of response, and sometimes manages to fight it off; a single exposure does not guarantee infection. But Agnes’s body, it seems, not only produced sufficient and strong enough cells to fight the virus off the first time, it then produced a whole raft of those killer Ts, flooding her system with guardians whose sole brief was to keep an eye out for cells infected with HIV. The infected cells have a distinct pattern of little bumps on them, called epitopes, which act like a red rose in the lapel as far as the killer Ts are concerned, letting them know just which cells they want to hunt down. Then every subsequent time - probably thousands of times - that HIV got into Agnes’s body, her killer T cells drove it back. A person does not normally maintain a large number of killer T cells for a long period - just long enough to kill something off, then production drops. But in Agnes, fairly constant exposure to HIV kept her killer T cell count high.

This conclusion was reinforced when Plummer and his team noticed that women who take a ’sex break’ - who make a trip home to the village for a few weeks, or save up a little money and leave sex work for a while to try selling shoes instead, or hook up with a regular who keeps them in cash for a year or two - were far more likely to get infected, almost immediately, if they returned to sex work, even though previously they had had years of apparent immunity. On the break, their bodies stopped making the killer T cells, leaving them vulnerable again.

If you would like to read the full article, and I highly recommend it as it is an amazing read, click the image below.