Lessons from the failed WHO Blue Nile Health Project in central Sudan, 1980-1990
The 10-year Blue Nile Health Project was initiated in 1980 among the 3 million people living in the irrigation systems of the Gezira area in central Sudan in order to evaluate an Integrated Strategy, including engineering, biological and ecological methods, as well as the conventional insecticides and drugs (Gaddal et al 1986, Najera et al 1998, Jobin 1999). The Blue Nile Health Project was also meant to go beyond the short experimental Garki Project, to be a permanent large-scale demonstration of an Integrated Strategy, to show that it could durably suppress even the unusually intensive malaria transmission in the Gezira. The intensive and widespread malaria transmission in the million hectares of the Gezira was due to wide-spread flooding in the poorly maintained irrigation and drainage system, and because of crowded and migrant agricultural populations in primitive housing, as well as the intrinsicly favorable ecology of the Blue Nile River valley for malaria. Ministry of Health programs in Sudan had also suffered previously due to governmental instability. Thus it was hoped that the Integrated Strategy would survive many of the problems facing those fighting malaria in Africa.
Within the $150 million dollar Project, the Integrated Strategy was also known as the Kitchen Sink Strategy, because every available method was used in a rational combination, except for the proverbial Kitchen Sink. For cost-efficiency, the Project was aimed at suppressing all water-associated diseases at once, including the parasitic disease schistosomiasis and diarrheal diseases such as cholera and typhoid fever. Although the Integrated Strategy quickly made dramatic and permanent reductions in schistosomiasis and diarrheal diseases, the results for malaria were more complex.
Firstly, the Integrated Strategy did reduce the malaria prevalence from 30% down to about 0.5% within the first 5 years. Also the prevalence was maintained at this extremely low level for the remaining 5 years of the Project, at low costs. The cost of the Integrated Strategy was reasonable; approximately $150 million to protect 3 million people over 10 years. The third of this cost apportioned to malaria control was thus less than $2 per capita per year, in 1985 US dollars. This is considerably less than the current strategy of the US Presidential Malaria Initiative.
In sum, the prevalence was kept extremely low for the 10 years of the Project. However when the Project was abruptly terminated after a 1989 military coup in the government - and expropriation of Project funds by the new military dictator - there was a quick rebound in malaria transmission. The new dictator also imprisoned many of the senior staff of the Project.
Part of the philosophy of the Integrated Strategy had been to include permanent improvements in drainage and water management in the irrigation canals and drains, as well as introduction of low-tech biological control measures such as fish and predatory snails, to deliberately overcome the uncertain political realities of governments in Africa. Improved control of siltation and aquatic weeds in the canals and drains was also developed. Unfortunately these permanent improvements had not been completed before the military coup of 1989.
Secondly, a regional drought in the Blue Nile River valley had important impacts. The drought initially helped reduce malaria transmission because it caused additional reductions in mosquito populations during the years when the drought was most severe, from 1980 to 1985. This was the time of the Great Ethiopian Famine in the upper Blue Nile River valley. Then, after 1985 heavy rains and flooding caused abrupt rises in mosquito populations. To make matters worse, the drought broke at the same time as the military coup, and the termination of the Project.
The severity of disease during the subsequent malaria epidemic was magnified by the loss of immunity in the people who had been protected during the previous 10 years (Najera et al 1998). Unfortunately the entire 3 million people in the Gezira Irrigated Area were thus caught in the Immunity Trap.
From the decade of experience in the Blue Nile Health Project in central Sudan, four important lessons were learned:
(1) A broad Integrated Strategy, including improved irrigation and drainage, can be effective even in areas of intensive malaria transmission such as the aging Gezira irrigation systems.
(2) The cost of the Integrated Strategy for suppression of malaria was very low, less than $2 per capita per year in 1985 US dollars.
(3) Unfortunately, more than 10 years were needed to fully establish the permanent environmental and engineering measures included in the Integrated Strategy. Establishment of such permanent improvements was sought to overcome potential governmental instability.
(4) Careful monitoring of rainfall should be part of anti-malarial programs in order to properly monitor the program impact on changes in transmission.
a. Gaddal A et al 1986 The Blue Nile Health Project, J Trop Med Hyg v68 (2). This entire issue was devoted to Blue Nile Health Project.
b. Jobin W 1999 Dams and Disease, Routledge
c. Najera et al 1998 Malaria Epidemics, detection and control, WHO Web Document WHO/MAL/INF 98.1084