Salome Simon doesn't have much. A one-room shack she rents in Majengo, a slum on the edge of Nairobi. A couple of kangas, the bright print wraps she wears as skirts, and a couple of blouses. A transistor radio, some aluminum pots and one little luxury, a gilded bottle of spicy perfume.
It isn't much to show for 23 years of hard work, on the job from 7 in the morning to 7 in the evening, every day but Sunday, when she goes to church, and once a year when she visits her family in Tanzania for a few weeks. She doesn't have a house of her own, doesn't have any savings, doesn't have a plot of land to grow maize or beans.
There is one other thing that Ms. Simon doesn't have: AIDS.
And this sets her apart from the thousands of other women who make a living as she does, selling sex in Nairobi.
She has had sex with five or six men a day -- sometimes 10 or 11 on a really good day -- since she moved to Nairobi in 1982. Through those years, women have sickened and died all around her: Her own daughter succumbed to AIDS last year. Yet Ms. Simon remains bizarrely -- miraculously, she says -- free of the virus.
"I can't explain anything; it's only God who could," she says, erupting in a belly laugh that makes her stout body quiver. She doesn't know why she doesn't have AIDS, when the infection rate among commercial sex workers is estimated to be as high as 80 per cent in these slums.
No one else knows why she doesn't have HIV-AIDS, either. But that's not for lack of trying.
Ms. Simon, now 44, was one of a small group of women identified, and made famous, by researchers from the University of Manitoba in 1990. At the time, the discovery of women apparently immune to HIV seemed to herald, at last, a solution to the AIDS pandemic.
It was a huge discovery -- but the clues that lie in the cells of Ms. Simon and few dozen other women remain stubbornly elusive. Hundreds of thousands of dollars and years and years of research later, an estimated 40 million people have been infected with HIV and more than three million more have died of the disease since 1990, but neither the Manitobans nor the scientists around the world who have joined their hunt have been able to extract the miracle in Ms. Simon, and turn it into either a vaccine or the thing that few AIDS researchers even mention any more: a cure.
This story begins not with AIDS but with an outbreak of a nasty venereal disease called chancroid, which causes suppurating ulcers on the genitals. It flared up in Winnipeg in the late 1970s, and a few infectious-disease experts at the University of Manitoba began to investigate. Before long, they had figured out how to grow the bacteria that causes chancroid in the lab -- but the outbreak had been brought under control, and they were left without patients.
There it might have ended, had a Manitoba researcher not been talking to a colleague from the University of Nairobi at a conference a few months later. "You want chancroid?" the Kenyan asked. "Have we got chancroid. Come on over."
So they did, launching a scientific relationship that has lasted more than 25 years and led to some key findings in a global pandemic that was, even then, brewing in Kenya.
The first Manitoban to go to Nairobi was microbiologist Allan Ronald, who now works in Uganda. He arrived in 1980 and quickly noticed that there was no shortage of other diseases endemic in the area -- sexually transmitted infections such as chlamydia and gonorrhea were rampant. He also noticed that the people seeking help at clinics for these infections all frequented prostitutes.
So the Canadian researchers set up shop in Majengo, an industrial slum on the edge of the city and the site of the world's biggest market for mitumba -- second-hand clothes. With traders from all over East Africa coming to hunt for bargains among the bales of First World castoffs, the market is a magnet for trade, complete with food stalls, tearooms and hostels for the travellers. It's also a natural centre for sex work.
In the crowded alleys, where sewage runs in concrete drainage ditches, there is a warren of little mud-brick houses, their roofs made of sheets of zinc. Each contains just a bed -- a good hard bed, the owners will explain, because on a soft one all those puffing, pumping men can give you bruises. The travellers stop in here, and so do plenty of local residents -- police officers, civil servants, welders, street sweepers, teachers and taxi drivers pay 50 shillings (80 cents) for an encounter with Ms. Simon or one of her many colleagues.
"The men were travelling to that community to have sex, but the prostitutes weren't moving around, they lived in their own houses -- so the team established a clinic in the middle of the community to start studying the epidemiology," says Joanne Embree, a pediatrician and Nairobi veteran who heads the University of Manitoba's department of medical microbiology and infectious disease.
In those first few years, the Manitobans did some important research on sexually transmitted diseases, and the impact on children whose mothers were infected with gonorrhea or chlamydia. But the discovery that would rock the scientific world came not in the large and carefully monitored studies, but on the whim of a grad student.
Joan Kreiss, an infectious-disease fellow from the University of Washington, joined the project and decided to test blood samples from the sex workers for HIV. Her colleagues were skeptical (at the time, the disease was linked almost entirely to gay men in North America) and no one was prepared for the results: Well before Kenya had its first documented case of AIDS, 65 per cent of the women tested had been infected with HIV.
The news did not go over well: The government of Kenya threatened to deport the Canadians and shut down the whole project. "The government said, 'It's not true what you are saying! You're going to drive the tourists out!' " recalls Elizabeth Ngugi, a community-health professor at the University of Nairobi who has been a key member of the project since it began.
The Canadians rode out the storm, research on the Majengo women began in earnest and, in the next few years, the Manitoba-Nairobi partnership yielded two major discoveries.
The first was that mothers pass HIV to their babies in breast milk. Researchers already suspected some transmission this way, but Dr. Embree and a colleague showed that the longer a mother breastfed, the higher was the risk of transmission -- up to 44 per cent if she nursed for more than a year.
The second big discovery was that a person with a conventional sexually transmitted infection such as syphilis has a much higher chance of being infected with HIV -- as much as 70 per cent higher. The implications were stark for communities such as Majengo, where syphilis was rife.
But the discovery of the HIV-resistant women is what truly rocked the world of infectious disease.
Frank Plummer is one of Canada's better-known scientists; as director of the Centre for Infectious Disease Prevention and Control in Ottawa, he is the point man on everything from SARS to West Nile to that scary fever a tourist from Africa develops that may just be Ebola. But as a student in the early 1980s, he did some research with the Majengo project, and was "stunned" when he heard in 1985 that two-thirds of the women there were already HIV-positive.
"It was something totally out of the blue," he recalls. When he was in Kenya, he says, "we had no people who were sick with AIDS; it wasn't visible in our study. The initial enrolment . . . were all healthy."
There was little inkling at the time that there was any serious presence of AIDS in Africa, and the virus was believed rarely to be transmitted in heterosexual encounters, and difficult for women to catch. "So we asked a question: How did 65 per cent of these women get infected?"
Dr. Plummer moved back to Nairobi to immerse himself in the issue, and by 1988 he had noticed something bizarre about the prostitutes: Many were sick, but many more were still testing negative, and he concluded that a small number of the women -- perhaps 5 per cent -- were, he says, "basically immune to HIV. Their immune systems for whatever reason are able to recognize and kill" the virus.
"We did the models and found that these women were not just really, really lucky -- it was beyond the statistical chance of luck playing a role," says Keith Fowke, now a professor of medical microbiology in Winnipeg and then a student working under Dr. Plummer. "We estimate that many of these women have had 500 to 2,000 sexual exposures to infected men when they weren't using a condom."
Even more bizarre, the longer a woman had been selling sex, the less likely she was to be infected.
These findings were so strange that Dr. Plummer and his team couldn't get them published until 1990, and even then it wasn't until an international AIDS conference in Amsterdam in 1993 that the implications were widely appreciated.
He now believes there are pockets of HIV-resistant people all over the world, but few provide the obvious opportunity for study that these women do because of the fact that they are steadily exposed and still resistant.
When Dr. Plummer and his team honed in on the biological workings in the resistant women's bodies, things got even more interesting: "We looked for antibodies, and there were none."
So something else was going on.
"We started looking at their immune system," Dr. Fowke says. "HIV was able to establish initial infection and the immune system was able to clear it . . . We've really found cells that can kill HIV in these women."
Those, of course, are magic words: In 1982, the government of then-president Ronald Reagan declared that the solution to the new AIDS threat was a vaccine, and U.S. scientists hoped to have one ready within a year or two. More than two decades later, the target is still at least another 10 years away.
HIV has proved to be a fiendishly clever virus, one that thwarts most of the conventional approaches in vaccinology. But if these women could somehow kill off the virus, harnessing the source of their immunity could allow frustrated vaccine researchers to trigger the same mysterious process in other people.
Soon a team from Oxford University was at work: It figured out which portions of the virus were being recognized by the women's immune cells and then knit them together as a potential vaccine. But the results were so disappointing that it never reached a large-scale test, and so it was back to the drawing board for the Manitobans and their Kenyan partners.
"The model we're working on now," Dr. Fowke says of the resistance women, "is that they have some sort of natural vaccination -- either they were exposed to a virus that was defective that served as a vaccine, or they were initially infected and the immune system cleared it."
Even with the vaccine still on the horizon, the research from Majengo has been of huge value to medical science -- and yet it's surrounded by a rising wave of tension.
The two universities clearly have benefited from their partnership. Many young Kenyan researchers studied in Winnipeg. "Now, we have a pool of people who have been very well trained in the West," says Walter Jaoko, head of microbiology at the University of Nairobi, "but we don't have the facilities."
That soon will change with a $3.8-million, state-of-the-art research laboratory being built on the campus with a grant from the Canada Foundation for Innovation.
At the same time, the Canadian researchers had opportunities they would never have had at home. ("It's been incredible for us," Prof. Embree says.) And many -- most notably, Dr. Plummer, now scientific director of the National Microbiology Laboratory in Winnipeg as well as the nation's chief infectious-disease expert -- have made major names for themselves.
And through the years, millions of dollars in research money have moved through this project, about $23-million handled by the University of Manitoba alone. There have been grants from Canada's Medical Research Council, the Rockefeller Foundation, the European Economic Council, Britain's Wellcome Trust, the International Development Research Centre in Ottawa. Last June, Dr. Plummer and his team won a coveted Challenge Grant for $9.2-million from the Bill and Melinda Gates Foundation.
All those millions, and yet Ms. Simon -- a participant since the research began and now one of just two original participants known to be HIV-free -- still has sex for 80 cents in a fly-filled, mud-walled room. (In the past four years, only 20 of the 500 women who originally enrolled in the study in 1984 have been seen at the clinic, and 18 of them are now HIV-positive.)
In exchange for taking part in the research, all the Majengo women receive free basic health care and counselling. Since the start of last year, those with fully developed AIDS also receive free antiretroviral medication, which can keep an infected person alive and healthy for decades. But this is no perk. The drugs are supplied by the U.S. President's Emergency Plan for AIDS Relief, and are now free to all Kenyans.
Why did the medicine take so long? "Until a few years ago, when the prices came down, it was unimaginable," says Larry Gelmon, who co-ordinates the project for the University of Manitoba. "We were sorry about it and conscious of the need but . . . this project for years has been working on a shoestring and funds were unavailable."
As well, the researchers hold annual meetings where they try to gather the women and explain what they are working on. But a quick survey of the women in the clinic's waiting room on a bustling morning yields not one who says she understands what is being done with the blood she donates.
This, says the clinic's primary-care doctor, shouldn't come as a surprise. "At some point," Charles Wachichi explains, "you realize that these women are resigned to having to struggle for their existence -- they don't give a lot of thought to their special status. They just wake up and struggle for their daily bread. . . . The novelty tends to be sort of lost."
It's certainly lost on Ms. Simon, who says she has no idea why she is like she is -- only that it's of great interest to the Canadians. She came here from Bukoba in Tanzania in 1982 after her husband deserted her and their three small children. "There was nothing else I could do to get money so quickly -- I needed money to keep my family."
Now 44, she has small grandchildren, but still plies her trade -- as many as 50,000 men since joining the project -- and hates it.
"Get me a job and I'd leave Majengo," she says quickly. "But my education level is very low, it's not enough, and I have no skills. If I had the money, I'd start a business and leave this work."
But she earns so little, she says, that there is never enough left, once the rent is paid, food bought and school fees for her grandchildren sent home to Tanzania, to start saving for a kanga stall or fruit stand. A decade ago, she sold shoes for two years in the market, but the business failed. "And when it did, I had nothing else to do but go back to prostitution."
And so, while she is grateful for the prompt, free service at the clinic, she feels that she has been on the losing end of this partnership with the Manitobans.
"I feel they take advantage of me, because I've made such a big name all over the world [for the project] but I'm still in this business.
"I need something to lift me out of Majengo."
Her frustration is echoed by the Kenyan nurses and counsellors at the little clinic. "These women, 20 years later, they're still in these small rooms," one irate staffer says, adding that she and her colleagues suspect the researchers privately want the women to keep working: "With no sex workers, what would happen to their research?"
According to Prof. Ngugi, who has worked intimately with the women for 20 years, "this has given the world such a huge body of knowledge, but what has the world done to help them change? . . . Quite clearly there is an imbalance."
A few years back, a grant from the Canadian International Development Agency allowed her to train 120 of the women so they could leave prostitution behind. Two-thirds made the transition, she says, and many others would have, but died of AIDS first.
Now, researchers such as Larry Gelmon argue that there's little more they can do. "To be totally crass," he says, "it would be in our interest not to counsel them or give them condoms -- it's good for us, the more transmission there is."
And it isn't easy to offer a prostitute a worthwhile option, he says. "Most women in studies say they wouldn't do it if they didn't have to. But if they could earn 1,000 shillings a day from sex work or 400 from a fruit stand, they say, 'I'm going to go where the money is.' "
Dr. Plummer agrees that the women should be offered a way out. "I don't know what those ways out are, though, and anything we could do is just working on the margins. It's unlikely we'll be able to do anything to get them to the point that they're not partially dependent on sex work: You only make so much money selling tomatoes or weaving baskets."
In his cramped university office, Dr. Jaoko bristles at the suggestion that Ms. Simon and the other women have been exploited. "It's unfair to compare people's scientific progress with the life of women in Majengo. We give them services they would not get anywhere else. . . . They're there of their own volition. If they felt ill-treated, they would always leave . . .
"We're a scientific group and not a charity. It's not a personal gain; it's an international gain. We're looking at innovative ways to develop a vaccine which will benefit globally. And you can't say any research group has done research and lifted up an entire community. It doesn't happen -- ever."
Finally, he says, any source of research grants handed "a funding proposal saying you were going to spend the money on training for women . . . wouldn't accept it."
There is no question the project has had enormous impact. Despite her criticism, Elizabeth Ngugi is the first to say so.
"From my perspective, if I did not get involved with the Canadian university, the impact of HIV-AIDS on this country would have been much greater -- I'm not just saying that, the facts are there. We distributed the largest number of condoms in the country: Seven million condoms is not a joke."
It was Prof. Ngugi, then a nurse taking an extra course, who launched the outreach work that established this project. She began by tromping through Majengo, right up to Ms. Simon and the other women as they sat on three-legged stools outside their rooms waiting for customers. "I walked in the mud and in the sun and in the rain and in the dust," she says, shaking her head as she remembers teaching the women that sexually transmitted diseases really could be treated and inviting them to the clinic.
Hers was the first medical team anywhere, she says, to try to organize prostitutes directly. "And we got them to 80-per-cent condom use after the first year."
Kenyan men detest condoms, she explains, but she was able to persuade the sex workers that by presenting a united front, they could demand that clients use them. "If you are all saying, 'No sex without a condom,' where will these men go?"
Even today, many members of Nairobi's academic establishment flinch at the idea of working with prostitutes. Dr. Ngugi clearly adores them -- interested in their well-being as much as intrigued by the scientific challenge they present. She has received $17-million over the past 16 years from CIDA to fight AIDS and to establish a regional training network to share the discoveries made in Nairobi.
In Majengo, there are the immediate benefits, including the dramatic drop in chlamydia and gonorrhea, once endemic and now rare, and the longer-term payoff from simply having a better understanding of HIV. (Right now, University of Manitoba researcher Stephen Moses is doing a major study on the role of male circumcision in lowering the risk of infection.)
The project has also identified a group of women who are "non-progressors," or HIV controllers. They have been infected for more than 15 years but not progressed to fully developed AIDS. Their immune systems, too, offer hope of a new response to the disease.
Dr. Plummer says the team now knows several different genes are involved in whatever protects the resistant women, and by tracking family members, it has "good evidence" that resistance runs in families. Relatives of HIV-resistant women are about half as likely to be infected as someone who isn't related, "so we're going to do a whole genome analysis," he says.
But there is one grim -- and peculiar -- twist to the immunity: "The resistance is not absolute," Dr. Fowke explains. "So, occasionally, some women that we call resistant to infection do become infected."
What's peculiar is the apparent common denominator to all the women to whom this happens: Despite eight to 10 years of resistance, they're suddenly infected after taking a break from the job that supposedly endangers them.
"We believe their immune system is protecting them somehow," Dr. Fowke says, "but when they go on a break, that immunity is fading, and when they come back, we see HIV almost right away. Our hypothesis is that their immune system isnot fully ramped up."
As a result, all women who do take a break, such as Ms. Simon's trips home to Tanzania, are asked for blood samples before they go and when they come back, so he can measure any difference in immune response.
Baffling wrinkles like this make Dr. Fowke admit that sometimes an AIDS vaccine "feels impossibly far away. . . . We know more about HIV than any other pathogen at all, yet we still can't get a vaccine that is protective. All our knowledge about these HIV-resistant people is interesting and I feel it's important, but it's still a long way off from a vaccine. And that's frustrating."
Then again, "one of the things that I'm proudest of in our work is, we haven't cured AIDS in any way, but what we did is change people's thinking. Up until then, if people wanted to understand HIV, they were studying people who were infected . . . and in this case, we're studying people who are an immune success story."
Now, the Manitoba team's strategy is, in essence, to identify all the things that are different in these women's bodies, and then see if one of them is what neutralizes HIV. So far, no one factor is found in all of the women, so it appears likely that there many overlapping traits, including some that are genetic.
"The thing that makes this group exciting," Dr. Fowke says, "is that the answer is already there and we're looking for it -- we're not trying to find out if it exists."
Prof. Ngugi shares his excitement, but only so far. "It's fascinating, but also sometimes I feel very sad," she says, thinking of the women of Majengo. "Sometimes you are not a scientist but a friend, and you feel the emptiness inside."
For her, Salome Simon notes, pointedly, it will take more than free drugs or even a vaccine to make the emptiness go away.
After all, she's immune to AIDS.
Stephanie Nolen is The Globe and Mail's correspondent in Africa.