African trypanosomiasis is a widespread disease of livestock which is a major
constraint to livestock production, mixed farming and the rural economy. The Jos
Plateau in Nigeria was historically free of tsetse flies and trypanosomiasis and this
lack of disease attracted large numbers of cattle keeping pastoralists. The area now
plays an important role in the national/regional cattle industry, holding 300,000
pastoralists and over a million cattle, ~ 7% of the national herd. However, over the
past twenty years tsetse flies have (re)invaded the Jos plateau and trypanosomiasis is
now a significant problem. Little is known about the distribution and overall
prevalence of the disease across the Jos plateau or about the habits and customs that
could affect the epidemiology of the disease in this area. This knowledge is essential
if successful interventions to reduce its impact are to be put in place.
To bridge this gap, a longitudinal two stage cluster survey was carried out in 2008 to
determine the prevalence of bovine trypanosomiasis. The study showed that the
prevalence of trypanosomiasis across the Jos plateau was 46.8% (39.0 – 54.5%) with
no significant seasonal variation. T. b. brucei was present at a prevalence of 3.3% (1%
– 5.5%); T. congolense savannah at a prevalence of 27.7% (21.8% - 33.6%); T. vivax at
a prevalence of 26.7% (18.2% - 35.3%). Although there was no significant seasonal
variation in prevalence across the Jos plateau, seasonal variations were observed at
village level to create 3 distinct groups. Group 1 villages (50.0%) which followed the
expected pattern of low prevalence in the dry season and high prevalence in the wet
season; Group 2 villages (16.7%) where there was no seasonal variation; Group 3
villages (33.3%) where paradoxically the prevalence was higher in the dry season and
lower in the wet season. This reversed epidemiological pattern is attributed to the harsh
climatic conditions of the dry season which reduce resistance to infection in cattle and
increase vector – host contact. Migration was shown to be a significant risk factor for
trypanosomiasis infection and the dry season was shown to significantly increase the
effect of all risk factors.
Participatory rural assessment was also conducted to investigate socio – economic
factors and knowledge, attitudes and practices concerning tsetse and
trypanosomiasis. The results of the participatory rural assessment exercise show that
trypanosomiasis is well recognised by farmers on the Jos plateau. They are aware of
the animal health and production disadvantages associated with it and make
considerable efforts to control it, along with other livestock diseases. However, they
lack the adequate knowledge to effectively control these diseases themselves and
there are gaps in veterinary service provision. Wealth ranking showed that the
majority of pastoralists in the study were either in the ‘middle’ or ‘better – off’
groups. Only 6.1% were classed as poor.
Anaemia as an indicator for trypanosomiasis was investigated and FAMACHA
charts were evaluated as a potential penside test for anaemia. Results show that
anaemia in cattle on the Jos Plateau is not strongly related to trypanosomiasis and
that the FAMACHA chart is a poor test for anaemia in cattle.