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ing these industries is appropriate control of livestock and
wildlife pests and diseases.
2.2.4.1 The livestock/wildlife interface in sub-Saharan
Africa
In most of SSA livestock and wildlife share similar habitats
and hence, at times compete for resources. This coexistence
has never been easy and there has been a long-standing conflict
between livestock owners and animal health authorities
on the one hand and, wildlife conservationists on the
other. This conflict is largely based on differing attitudes
towards control of livestock diseases associated with wildlife.
Livestock and wildlife disease problems are frequently
bi-directional at the livestock/wildlife interface and the situation
becomes more complex when humans are involved.
Livestock and wildlife diseases can be grouped into three
different categories as follows:
1. Infectious diseases associated with wildlife known to
cause diseases in domestic livestock. The single most
important factor responsible for causing an outbreak of
any of these diseases is probably the direct or indirect
(vector) contact of infected wild hosts or populations
with susceptible domestic animals at the interface of
their ranges, where mixing has occurred on common
rangeland, or, where other resources, like water are
shared. Diseases in this category include foot and mouth
disease (FMD), African swine fever (ASF) and classical
swine fever (hog cholera), trypanosomiasis, theileriosis
or corridor diseases, African horse sickness, Rift Valley
fever (RVF), bluetongue, lumpy skin diseases, malignant
catarrhal fever and Newcastle disease (Bengis et
al., 2002).
2. Multispecies diseases that affect both livestock and
wildlife. Transmission of these diseases can occur in
both directions, although in certain regions, dominant
role players have been identified. These diseases are
generally fatal to both wildlife and livestock and are
frequently zoonotic. Examples of such disease are anthrax,
rabies and brucellosis (Bengis et al., 2002).
3. Alien diseases that infect wildlife and domestic livestock.
Some of the best examples in this category are
certain diseases historically alien to SSA, which were
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probably introduced into the African continent with
the importation of domestic livestock from Europe and
Asia during the colonial era. Indigenous African freeranging
mammals are generally susceptible to these foreign
agents and significant morbidity and mortality may
be encountered in both wildlife and domestic livestock.
Such diseases include rinderpest, canine distemper, bovine
tuberculosis, African horse sickness and African
swine fever (Bengis et al., 2002).
2.2.4.2 Selected diseases and pests of livestock and
wildlife
Rinderpest. Rinderpest is a viral disease introduced into Eritrea
from India during the pre-colonial era either by the Italian
army in 1887/1888, or by a German military expedition
that brought infected cattle from Aden and Bombay to the
East African coast. The disease killed more than 90% of all
cattle population and wildlife (Henning, 1956). However,
during this pre-colonial era, even without advanced technology,
cattle farmers in South Africa managed to contain
rinderpest through immunization of cattle, by using the bile
of animals that died of the disease and, by end of 1898,
the disease was under control and temporarily disappeared
from South Africa. The disease resurfaced again in 1901
because cattle immunization against rinderpest was limited
to South Africa and because SSA lacked strict border control
(Henning, 1956). The situation remained unchanged during
the colonial period, making rinderpest one of the most devastating
diseases of both livestock and wildlife. Advances in
AKST have created efficient vaccines to contain rinderpest
and, currently, the disease is no longer a threat. Globalization
has also played an important role and now, under the
global rinderpest eradication program (GREP), a total of 25
SSA countries have managed to declare themselves or zones
within their country free from this disease. In addition, six
SSA countries have been declared rinderpest-free by the
World Organization for Animal Health (OIE) (OIE, 2007).
The eradication of rinderpest (not only in some SSA
countries, but in most western and Asian countries) has been
made possible through effective vaccination and modern diagnostic
techniques. Although rinderpest is a disease of both |