Identification of trypanosomes isolated by KIVI from wild mammals in Côte d'Ivoire: diagnostic, taxonomic and epidemiological considerations.

In Côte d'Ivoire, a comparative study was carried out on 122 wild mammals by parasitological and serological examination and by in vitro isolation of trypanosomes from fresh blood (KIVI). Thirteen isolated stocks were studied by isoenzymes and compared with Trypanosoma congolense and T. brucei bouaflé group reference stocks. Of the 122 animals, only 22 were positive on blood smears while 88 were KIVI positive and 92 were CATT/T. b. gambiense positive. For six stocks identified by isoenzymes as T. congolense, the agreement between ELISA and CATT was good (75%). As compared with CATT, antigen detection ELISA was not satisfactory for T. brucei (20%). Out of 18, 16 stocks represented a separate zymodeme (seven T. congolense and nine T. brucei) and a high genetic heterogeneity was observed. For T. congolense, savanna, kilifi and forest groups were represented by one zymodeme each. The four remaining zymodemes while put into this T. congolense group, were strongly independent of each other. Morphology indicated that those new zymodemes correspond to T. congolense. In the other hand, five new zymodemes fit into T. brucei classification.

[Epidemiologic study of bluetongue in sheep, cattle and different species of wild animals in the Ivory Coast]. / Etude épidémiologique sur la fièvre catarrhale du mouton chez les ovins, les bovins et différentes espèces d'animaux sauvages en Cóte d'Ivoire.

Between 1992 and 1993, a serological survey was conducted in Côte d'Ivoire on 623 sera from sheep, 215 sera from cattle and 211 sera from wild herbivores. These sera were tested for bluetongue virus (BTV) antibodies using an agar gel immunodiffusion test. The purpose of this survey was twofold: to establish the incidence of bluetongue in the country, and to analyse the putative role of BTV in the reproductive pathology of sheep. Seroprevalence was 52 +/- 4% in sheep, 95 +/- 3% in cattle, and 56 +/- 7% in wild herbivores. The authors found antibodies against BTV in kob (Kobus kob Erxleben, 1777), common waterbuck (Kobus ellipsiprymnus Ogilby, 1833), roan antelope (Hippotragus equinus Desmarest, 1804), buffalo (Syncerus caffer Sparrman, 1779), hartebeest (Alcelaphus buselaphus Pallas, 1766) and elephant (Loxodonta africana Blumenbach, 1797). A significant difference was found in seroprevalence in sheep between the three areas covered by the survey. Antibody prevalence increased significantly with age in sheep and wild herbivores, and seroprevalence was higher in dams with a history of abortion. It can therefore be concluded that bluetongue is enzootic in Côte d'Ivoire.

[Prevalence of Trypanosoma infections in different species of wild animals in the Comoé national park on the Ivory Coast: preliminary results of the comparison of 3 diagnostic methods]. / Etude de la prévalence des infections à trypanosomes chez différentes espèces d'animaux sauvages du parc national de la Comoé en Côte d'Ivoire: résultats préliminaires sur la comparaison de trois méthodes de diagnostic.

Compared with the numerous studies of trypanosomosis in domestic animals, few such studies have been carried out on wild animals in West Africa. Preliminary results on the comparison of three detection methods (thin smears, detection of trypanosome antigens by ELISA-Test and Kit for in vitro isolation of trypanosomes, KIVI) in wild animals of Comoe Game Reserve in Côte d'Ivoire confirm the actual presence of trypanosomes; however, no accurate identification of those parasites has been possible, but work is in progress to clarify the taxonomical status of stocks isolated by KIVI.