Distribution and application of ELISA for the seroprevalence of tick-borne diseases in Central Equatoria State, Sudan.

This study was carried out to estimate the prevalence of Theileria parva, Theileria mutans, Babesia bigemina and Anaplasma marginale antibodies among naturally infected cattle in Central Equatoria State, Southern Sudan using indirect enzyme-linked immunosorbent assay (ELISA). Three locations (Khor Rumla, Nyaing and Gumbo) were selected and surveyed every 3 months during the period from January to December 2005. Six cattle herds in the three locations were visited four times during the study period. During each visit, 150 serum samples were collected from indigenous cattle of both sex and of different age groups. Assessment of antibodies against tick-borne diseases was carried out using indirect ELISA. The overall seroprevalence rates of T. parva, T. mutans, B. bigemina and A. marginale were found to be 58.2%, 88.9%, 51.1% and 37.8% respectively. The highest seroprevalence of T. parva was observed in Gumbo (69%). An overall seroprevalence of 43.3% for T. parva was reported in July which was significantly lower than other seasons. Older animals showed higher seroprevalence than younger ones. The implications of these results on the epidemiology of tick-borne diseases are discussed with emphasis on East Coast fever.

Reliminary survey of ticks (Acari: Ixodidae) on cattle in Central Equatoria State, Southern Sudan.

In a preliminary survey conducted in 2005, the species composition and seasonality of ticks infesting cattle in Central Equatoria State, Southern Sudan was determined. Three locations were selected (Gumbo, Khor Rumla and Nyaing) and surveyed every 3 months. Two cattle herds in each of the three locations were visited four times during the study period. Total body collections of ticks were made from each of five cattle (Nilotic Zebu breed) kept in six different herds. Four tick genera and ten species were identified. The tick species identified were Amblyomma lepidum, Amblyomma variegatum, Boophilus annulatus, Boophilus decoloratus, Hyalomma marginatum rufipes, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus praetextatus and Rhipicephalus sanguineus group. The highest number of ticks was collected in October during the rainy season. A finding of great significance was that R. appendiculatus, vector of East Coast fever, has now firmly established itself throughout the year with possible implications for cattle production in Central Equatoria State.