The WHO failed to eliminate malaria in Zanzibar in the 1950s–1960s.

The ending of the WHO program in Zanzibar led to an epidemic of rebound malaria.

Zanzibar’s rebound malaria epidemic was predicted by scientists, yet still occurred.

The ethical dilemmas of rebound malaria remain unresolved in the present.

This article presents a case study of the WHO’s malaria elimination attempt in Zanzibar and the decades after the program’s conclusion in 1968. Drawing on archival, ethnographic, and interview data, we find that Zanzibar experienced a rebound malaria epidemic in the 1970s–1980s when prevalence rates surged higher than they were prior to the WHO’s intervention. We show that scientists were aware of the risks of rebound before it happened and recognized the rebound epidemic as it was happening. We argue that many of the challenges facing Zanzibar in the 1960s remain dilemmas today, and many of the ethical questions about rebound malaria remain unaddressed.

Malaria

Malaria elimination

Zanzibar

Rebound malaria

World Health Organization

Global health ethics

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