The Environmental History of Africa

Topic 8 - Livestock Disease: Trypanosomiasis in Tanganyika

  1. Example of Disease/Disease and Human Disease Interaction in Uzigua, Tanzania. These is baseline historical data on Uzigua. How does disease account for historical patterns?:
    1. Uzigua area opposite Zanzibar/ cultivators/ erratic rainfall/people occupy river valleys were moisture available.
    2. Uzigua is the northern edge of trypanosomiasis area with wild animals as vectors/little evidence of human trypanosomiasis.
    3. Missionary records indicate dramatic losses in cattle and famine in 1907-32 period.
    4. Famines in 1894-96, 1898-1900, 1907-08, 1910, 1916-18, 1925, 1932-35.
    5. Devastation by 1891 rinderpest epizootic (death of virtually all domestic and wild animals from rinderpest eliminated those animals that had trypanosomiasis resistance).

  2. Typanosomiasis epidemiology and theories about it very pertinent to historical record.
    1. In 1901 British doctor in Uganda discovered new disease (laethargy and fever). 1903 90,000 died; by 1906, 200,000 had died.
    2. Assumed to come from Congo with soldiers from Stanley expedition to Emin Pasha.
    3. In all cases, colonial medical authorities attributed outbreaks in early colonial period were to external sources (Congo Free State, Mozambique) i.e. migratory thesis.
    4. By contrast, ecological thesis of John Ford: basic factors of trypanosomiasis in place for long time (humans, animals, protozoan, tsetse, wild animals) outbreaks caused by disruptions of balance between them.
    5. Ford argued that limited contact between factors allowed resistance to build in human and cattle pop.
    6. Colonial officials had assumed that population decline had expanded bush and tsetse in simple relationship bringing spread of disease.

  3. In Uzigua we can see interaction of several ecological factors to account for outbreaks of trypanosomiasis and famine.
    1. Mission records give good account.
    2. Precolonial reports from 1811 and 1880s indicate presence of both cattle and tsetse; chief obstacle to cattle population was water and not tsetse.
    3. Ecologist John Ford's thesis holds that symbiosis of cattle and tsetse indicates an ecological balance had been achieved between humans, livestock, and disease.
    4. Beginning of crisis in 1891 with rinderpest (cattle and game killed) and again in 1901.
    5. Rinderpest killed trypano-tolerant animals and host population for protozoan that causes the disease. By early twentieth century these events had created a large trypanosomiasis free area, because of the death of potential host animals.
    6. Missionaries encouraged the idea that the area was ideal for cattle raising and imported new cattle from trypanosomiasis free northern zones.
    7. Five years later large numbers of cattle fell to trypanosomiasis.
    8. Colonial conscription for WWI reduced pop and cultivation declined
    9. Bush expanded and tsetse increased, creating a new ecology in which the disease and its vectors thrived. Non-immune cattle (brought from the north) died quickly.
    10. Colonial officials concluded expansion of bush was responsible and imposed new policies to control bush as solution.

  4. Ecology control?
    1. Key question is was control a conscious human strategy or a serendipitous product of environmental interaction.
    2. What was role of colonialism as opposed to purely environmental factor of rinderpest?
    3. Human decision to expand cattle keeping?