Spillover: Animal Infections and the Next Human Pandemic (61 page)

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Authors: David Quammen

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BOOK: Spillover: Animal Infections and the Next Human Pandemic
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Six years later came the blood sample that yielded the HIV-1 sequence now known as ZR59. One year after that, DRC60. The virus had spread and diversified. It was at large. No one can say whether either of those two patients had ever visited the Dispensaire Antivénérien for a shot. But if they hadn’t, they probably knew someone who had.

108

F
rom this point the story gets huge and various, literally going off in all directions. It explodes out of Léopoldville like an infectious starburst. I won’t try to trace those diverging trajectories—a task for ten other books, with purposes different from mine—but I’ll sketch the pattern, and then focus briefly on one that’s especially notorious.

During its decades of inconspicuous transmission in Léopoldville, the virus continued to mutate (and probably also to recombine, mixing larger sections of genome from one virion to another), and those copying errors drove its diversification. Most mutations are fatal mistakes, bringing the mutant to a dead end, but with so many billions of virions replicating, chance did provide a small, rich supply of viable new variants. The campaigns of injectable drug treatments, at the Dispensaire Antivénérien and elsewhere, may have helped foster this process by transmitting the virus quickly into more human hosts and increasing its total population. The more virions, the more mutations; the more mutations, the more diversity.

The HIV-1 group M lineage became split into nine major subdivisions, now known as subtypes and labeled with letters: A, B, C, D, F, G, H, J, K. (Don’t confuse those, if you can help it, with the eight groups of HIV-2, designated A through H. And why are E and I missing? Never mind why. Such edifices of labeling get built piecemeal, like slums of cardboard and tin, not with architectural forethought.) As time passed, as the human population of Léopoldville grew, as travel increased, viruses of those nine subtypes emerged from the city, radiating outward across Africa and the world. Some of them went by airplane and others by more mundane means of transport: bus, boat, train, bicycle, hitchhiking on a transcontinental truck. Foot. Subtype A got to East Africa, probably via the city of Kisangani, halfway between Léopoldville and Nairobi. Subtype C spread to southern Africa, probably via Lubumbashi, way down in the Congolese southeast. Seeping across Zambia, achieving rapid transmission in mining towns full of workers and prostitutes, subtype C proliferated catastrophically throughout South Africa, Mozambique, Lesotho, and Swaziland. It went on to India, which is linked to South Africa by channels of exchange as old as the British empire, and to East Africa. Subtype D established itself alongside subtypes A and C in the countries of East Africa, except for Ethiopia, which for some reason became afflicted early and almost exclusively with subtype C. Subtype G got up into West Africa. Subtypes H, J, and K remained mostly in Central Africa, from Angola to the Central African Republic. In all these places, after the usual lag of years between infection and full-blown AIDS, people began dying. And then there’s subtype B.

Sometime around 1966, subtype B crossed from Léopoldville to Haiti.

How it did that is unknown, and can probably never
be
known, but Jacques Pepin’s archival burrowing provides new support for one plausible old scenario. When the Belgian government abruptly relinquished its African colony, on June 30, 1960, under the stern encouragement of Patrice Lumumba and his movement, tens of thousands of Belgian expatriates—almost an entire middle class of civil servants, teachers, doctors, nurses, technical experts, and business managers—found themselves unwelcome and uncomfortable in the new republic, and they began flooding homeward. Crowding the planes for Brussels. Their departure created a vacuum, since the Belgian regime had pointedly avoided educating its colonial subjects. There wasn’t a single Congolese medical doctor, for instance. Few teachers. The country suddenly needed help. The World Health Organization responded, sending physicians, and the United Nations (through its Educational, Scientific, and Cultural Organization, UNESCO) also began enlisting skilled people to work in the Congo: teachers, lawyers, agronomists, postal administrators, and other bureaucrats, technicians, and professionals. Many of those recruits came from Haiti. It was a natural fit: The Haitians spoke French as did the Congolese; they came from African roots; they had education but very little opportunity at home under the dictatorship of Papa Doc Duvalier.

During the first year of independence, half the teachers sent by UNESCO to the Congo were Haitians. By 1963, according to one estimate, a thousand Haitians were employed in the country. Another estimate says that a total of forty-five hundred Haitians served hitches in the Congo during the 1960s. Evidently there’s no surviving, authoritative manifest. Anyway, lots of Haitians, thousands. Some brought families, some came alone. Among the single men, we can assume, few remained celibate. Most of them probably had Congolese girlfriends or visited
femmes libres
. For a few years it may have been a good life. But the Haitians were less needed and less welcome as the Congo began training its own people, especially after Joseph Désiré Mobutu seized power in 1965. Less still when, in the early 1970s, he changed his name to Mobutu Sese Seko, changed his country’s to Zaire, and announced a policy of
Zaireanisation
. Many or most of the Haitians, during those years, went home. Their time of being useful and appreciated black brothers from the Americas had passed.

At least one of those returnees, probably among the earliest of them, seems to have carried HIV-1.

More specifically: Someone brought back to Haiti, along with Congolese memories, a dose of HIV-1 group M subtype B.

You can see where this is going, but you might not expect how it gets there. Jacques Pepin’s research shed some new light on what may have happened in Haiti during the late 1960s and early 1970s to multiply and forward the virus. One thing that happened was that, from a single HIV-positive person in 1966 or thereabouts, the virus spread fast through the Haitian population. Evidence for that spread came later, from blood samples given by 533 young mothers in a Port-au-Prince slum, who agreed in 1982 to participate in a measles study at a local pediatric clinic. Tested retrospectively, those samples revealed that 7.8 percent of the women had been HIV-positive. That number was startlingly high, for such a newly arrived virus, and caused Pepin to suspect that “
there must have been a very effective amplification mechanism
” operating in Haiti during the early years—more effective than sex. He found a candidate: the blood plasma trade.

Plasma, the liquid component of blood (minus the cells), is valuable stuff for its antibodies and albumin and clotting factors. Demand for it rose sharply during the period around 1970, and to meet the demand a process called plasmapheresis was developed. Plasmapheresis entails drawing blood from a donor, separating the cells from the plasma by means of filtering or centrifuging, putting the cells back into the donor, and keeping the plasma as a harvested product. One advantage of this process is that it allows donors (who are usually in fact
sellers
, paid for their trouble and needing the money) to be tapped often rather than just a couple times per year. Giving up your plasma, for the good of others or for profit, doesn’t leave you anemic. You can go back and give again the following week. One
dis
advantage of the procedure—and it’s a huge one, but wasn’t recognized in the early days—is that a plasmapheresis machine, gargling your blood and the blood of many other donors over the course of days, can infect you with a blood-borne virus.

This happened to hundreds of paid plasma donors in Mexico during the mid-1980s. It happened to a quarter million luckless donors in China. Jacques Pepin thinks it happened in Haiti too.

He found reports of a plasmapheresis center in Port-au-Prince, a private business known as Hemo Caribbean, that operated profitably during 1971 and 1972. It was owned by an American investor, a man named Joseph B. Gorinstein, based in Miami, with links to the Haitian Minister of the Interior. Donors received $3 per liter. Their vitals were checked before they could sell plasma, but of course nobody screened them for HIV—which didn’t yet exist as an acronym, or an infamous global scourge, only as a quiet little virus that lived in blood. According to an article that ran in
The New York Times
on January 28, 1972, Hemo Caribbean was then exporting between five and six thousand liters of frozen blood plasma to the United States each month. The wholesale customers were American companies, which marketed the product for use in transfusions, tetanus shots, and other medical applications. Mr. Gorinstein wasn’t available for comment.

Papa Doc had meanwhile died, in 1971, and been succeeded by his son Jean-Claude (Baby Doc) Duvalier. Annoyed by the
Times
publicity, Baby Doc ordered that Gorinstein’s plasmapheresis center be closed. The Haitian Catholic Church condemned the blood trade as exploitation. Beyond that, the story of Hemo Caribbean drew little notice at the time. No one yet realized how devastating blood-product contamination could be. Nor did the CDC’s
Morbidity and Mortality Weekly Report
mention it, a decade later, when breaking the news that Haitians seemed especially at risk for the mysterious new immune-deficiency syndrome. Randy Shilts didn’t mention it in
And the Band Played On
. The only allusion to Haitian blood plasma that I recall, from the years before Jacques Pepin’s book, came during my conversation with Michael Worobey in Tucson.

Shortly before publishing on DRC60 and ZR59, Worobey coauthored another notable paper, dating the emergence of HIV-1 in the Americas. The first author was a postdoc named Tom Gilbert, in Worobey’s lab, and in the anchor position was Worobey himself. This was the work, based on analyses of viral fragments from archived blood cells, that placed the arrival of HIV-1 in Haiti to about 1966, give or take a few years. It appeared in the
Proceedings of the National Academy of Sciences
. Soon afterward, Worobey got a peculiar email from a stranger. Not a scientist, just someone who had caught wind of the subject. A reader of newspaper coverage, a listener to radio. “I think he was from Miami,” Worobey told me. “He said he worked in an airport that dealt with the blood trade.” The man had certain memories. Maybe they haunted him. He wanted to share them. He wanted to tell Worobey about cargo planes arriving full of blood.

109

T
he next leap of the virus was small in distance and large in consequence. Port-au-Prince is just seven hundred miles from Miami. A ninety-minute flight. Part of the project that Tom Gilbert undertook, in Worobey’s lab, was to date when HIV-1 had arrived in the United States. To do that he needed samples of old blood. Whether the blood had reached America in bottles, in bags, or in immigrant Haitians didn’t much matter for this purpose.

Worobey, serving as Gilbert’s adviser, remembered a study of immunodeficient Haitian immigrants that had been published twenty years earlier. It had been led by a physician named Arthur E. Pitchenik, working at Jackson Memorial Hospital in Miami. Pitchenik was an expert on tuberculosis, and beginning in 1980 he noticed an unusual incidence of that disease, as well as
Pneumocystis
pneumonia, among Haitian patients. He sounded the first alarm about Haitians as a risk group for the new immunodeficiency syndrome, alerting the CDC. In the course of clinical work and research, Pitchenik and his colleagues drew blood from patients and centrifuged it, separating serum from cells, so they could look at certain types of lymphocyte. They also froze some samples, on the assumption those might be useful to other researchers later. They were right. But for a long time no one seemed interested. Then, after two decades, Arthur Pitchenik got a call from Michael Worobey in Tucson. Yes, Pitchenik said, he would be glad to send some material.

Worobey’s lab received six tubes of frozen blood cells, and Tom Gilbert managed to amplify viral fragments from five. Those fragments, after genetic sequencing, could be placed into context as limbs on another family tree—just as Worobey himself would later do with DRC60 and ZR59, and as Beatrice Hahn’s group was doing with SIV
cpz
. It was molecular phylogenetics at work. In this case, the tree represented the diversified lineage of HIV-1 group M subtype B. Its major limbs represented the virus as known from Haiti. One of those limbs encompassed a branch from which grew too many small twigs to portray. So in the figure as eventually published, that branch and its twigs were blurred—depicted simply as a solid cone of brown, like a sepia shadow, within which appeared a list of names. The names told where subtype B had gone, after passing through Haiti: the United States, Canada, Argentina, Colombia, Brazil, Ecuador, the Netherlands, France, the United Kingdom, Germany, Estonia, South Korea, Japan, Thailand, and Australia. It had also bounced back to Africa. It was HIV globalized.

This study by Gilbert and Worobey and their colleagues delivered one other piquant finding. Their data and analysis indicated that just a single migration of the virus—one infected person or one container of plasma—accounted for bringing AIDS to America. That sorry advent occurred in 1969, give or take about three years.

So it lurked here for more than a decade before anyone noticed. For more than a decade, it infiltrated networks of contact and exposure. In particular, it followed certain paths of chance and opportunity into certain subcategories of the American populace. It was no longer a chimpanzee virus. It had found a new host and adapted, succeeding brilliantly, passing far beyond the horizons of its old existence within chimpanzees. It reached hemophiliacs through the blood supply. It reached drug addicts through shared needles. It reached gay men—reached deeply and catastrophically into their circles of love and acquaintance—by sexual transmission, possibly from an initial contact between two males, an American and a Haitian.

For a dozen years it traveled quietly from person to person. Symptoms were slow to arise. Death lagged some distance behind. No one knew. This virus was patient, unlike Ebola, unlike Marburg. More patient even than rabies, but equally lethal. Somebody gave it to Gaëtan Dugas. Somebody gave it to Randy Shilts. Somebody gave it to a thirty-three-year-old Los Angeles man, who eventually fell ill with pneumonia and a weird oral fungus and, in March 1981, walked into the office of Dr. Michael Gottlieb.

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