The Experiment Must Continue. Melissa Graboyes

The Experiment Must Continue - Melissa Graboyes


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were widespread drug shortages, and administration continued into the following day. The good news was that 76 percent of the total population took the pill: the campaign had succeeded in its goal. As the WHO report summed up, “the people of Zanzibar had made a rational cost/value decision.”12 Even skeptics could agree that the goal for the first year had been accomplished. If mass drug administration could happen consistently in future years, LF would be eliminated from the island.

      Between 2001 and 2007, Zanzibar continued yearly mass administration and distributed more than five million total doses of albendazole and ivermectin to the 1.1 million residents of the island. Over those six years, 70–80 percent of the total Zanzibari population received drugs.13 After the fourth year of mass drug administration (MDA), two sentinel sites measured only 1 percent and 0 percent microfilariae prevalence rates; after the fifth round of MDA, both sites had 0 percent prevalence.14 At that point the program was considered to be in the “terminal phase,” which consisted of maintaining zero transmission.15 The activities in Zanzibar indicate that it is possible to interrupt transmission and that MDA can be an effective strategy.16 It remains to be seen whether the parasite densities are low enough in humans (and that introductions of new infections from the mainland are rare enough) for all LF transmission to stop. While Zanzibar has been declared a successful example, claims about successful elimination are notoriously slippery, since the term implies that the disease will be gone permanently. We must wait and hope that this will be the case in Zanzibar.

      The WHO Progress Reports for the GPELF remind everyone of the clear path countries must take to attack the disease: begin by mapping the disease foci, undertake mass drug administration for five years, and, after this, a period of surveillance and eventual verification of disease elimination. Official WHO reports and plans make no mention of failures that might jeopardize the global campaign. In fact, quite the opposite sentiment is put forth. The plan remains to fully eradicate LF by 2020 and the claim is that the goal is half accomplished. International publications as early as 2006 were touting the program’s “remarkable achievement.”17 From some angles the news does look promising: among the fifty-three countries globally that have begun mass drug administration, thirty-seven have already distributed the drugs for five or more years as recommended. In Africa, ten countries have administered at least five years of drugs over 100 percent of their geographic area.18 Yet, of those thirty-seven countries, only five have moved into the surveillance phase that implies the disease has likely been eliminated.19 Those five countries—Sri Lanka, the Cook Islands, Tonga, Vanuatu, Niue—account for an amazingly small proportion of the global burden of LF.20 In Africa, the only country that is mentioned as having moved into the surveillance phase is Togo. (Zanzibar is not mentioned as a country that has moved into this phase because it is part of Tanzania, and the remainder of the country has not been nearly as successful as the island of Zanzibar.)21 There is something comforting in the linearity implied in these steps—that diseases really can be eliminated by following a simple master plan—but such formulaic prescriptions ignore the many uncertainties that continue to characterize eradication attempts. It remains unknown if five rounds of MDA will actually lead to halted transmission and permanent elimination of LF in most countries, and it is unclear how to keep areas free of LF in the longer run. It also remains largely unacknowledged that the history of past attempts in each place—whether failures of malaria elimination, or successes of other public health programs—will be important in determining how receptive local people are to these internationally backed activities. Although these short-term successes in Zanzibar are important and praiseworthy, it remains to be seen whether the program in Zanzibar actually “represents an excellent model for other countries.”22

       3

      FIRST ENCOUNTERS, FIRST IMPRESSIONS

      This chapter focuses on the chronological start of the medical research encounter by describing researchers’ initial arrival in a village. These narratives of elimination on Pate Island and Zanzibar point to a fundamental misunderstanding at the root of many “first encounters.” I look at how researchers arrived and introduced themselves to the communities, and at what information researchers shared with communities and how they shared it. I present detailed information about two historical attempts to eliminate lymphatic filariasis (LF) on Pate Island in the Lamu Archipelago, which was introduced in the preceding narrative, and on Ukara Island in Lake Victoria. I also discuss the modern attempt to eliminate LF in Zanzibar and eradicate it globally. The two historical campaigns had very different outcomes that allow us to ask a series of difficult questions: Did scientists purposefully misrepresent their work? Was it folly on the part of both sets of islanders to refuse the help of researchers who were trying to eliminate disease? What was the logic of turning down a seemingly low-risk medical intervention? Were the miscommunications and conflicts that plagued the programs on Pate Island and Zanzibar inevitable?

      These case studies of failed elimination attempts and aborted arrivals make a few important points illustrated in the snapshot of Goiny’s five days on Pate Island. First, communities had far more ability to change projects—or end them entirely—than most colonial medical researchers were willing to recognize. Second, although the medical departments and research teams often pretended that their work went on in a historical and political vacuum, East Africans disagreed. Local residents saw the research project as fully enmeshed in recent history, local politics, and their ongoing interactions with the government. Science was neither special nor solitary. While researchers assumed they were making first impressions, community members often viewed their work as repeat performances of past public health and medical research incursions. The chapter begins with information about the disease lymphatic filariasis; details the differences between what was planned by the Department of Insect Borne Disease (DIBD) workers versus what they shared with Pate residents; looks at how science interacted with local perceptions of government and local history; and, finally, examines how the failed attempt in Pate compared with a very similar project on Ukara Island. I conclude by returning to the ongoing global campaign to eradicate lymphatic filariasis.

       Filariasis

      Lymphatic filariasis (Wuchereria bancrofti in East Africa) is a parasitic disease transmitted by Anopheles mosquitoes and which has long been found in the region.1 Once a mosquito bites an infected person and ingests the parasite, the mosquito becomes a vector, able to transmit the disease to other humans through subsequent bites. The parasitic worms live and procreate inside the human body and produce millions of new microfilariae that lodge in the body’s lymphatic system. The lymphatic system regulates the fluid balance between tissues and blood, and damage to the system can cause swelling of the scrotum (hydrocele), or a swelling of the legs that results in thickening of the skin (elephantiasis). The disease is not typically fatal, and it takes many years—often decades—for a person to develop obvious symptoms. For a full depiction of the transmission cycle, see figure 3.1. Testing for filariasis requires blood samples (from either a vein or a finger prick) to be taken at night (typically after 10 pm), since it is only in the evening that the microfilariae become active in the peripheral blood; daytime blood tests produce false negatives.2 The nocturnal periodicity of the microfilariae in the peripheral blood corresponds to the night biting habits of mosquitoes, timing that encourages transmission of the parasite. By 1956, when the campaign on Pate Island began, effective treatment in the form of DEC (diethylcarbamazine) was available.

      FIGURE 3.1. Lymphatic filariasis disease lifecycle. Produced by Chris Becker.

      In the 1950s, the medical community disagreed about how important a disease filariasis actually was, and how many resources should be devoted to fighting it. While the Kenya Medical Department plowed ahead with elimination plans, the mission of the more circumspect Filariasis Research Unit (FRU) was to establish the true effects of LF: in their words, to see if filariasis was “so great a threat to the welfare and economy of the peoples that it would be justifiable to recommend that large-scale programmes of control be initiated.”3


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