Le polyparasitisme gastro-intestinal des ruminants domestiques dans la région des savanes de la cote d'ivoire

La région des savanes est le berceau de l'élevage des ruminants en Côte d'Ivoire. Elle renferme 65% du cheptel national bovin, 16% du cheptel ovin et 15% du cheptel caprin. En dépit de l'importance reconnue des strongles gastro-intestinaux, aucune étude épidémiologique n'y a été entreprise pour aboutir à des mesures de luttes judicieuses. La zone est régie par un climat soudanien dont la saison des pluies a une hauteur de précipitations moyennes de 1200 mm. La végétation est à majorité constituée de savanes arborée et arbustive. l'étude sur l'épidémiologie des strongles a été réalisée par des autopsies de 48 bovins, 144 moutons et 72 chèvres. Elle a permis l'inventaire des strongles présents dans la région ainsi que la connaissance de leurs évolutions saisonnières. La quasi-totalité des animaux sont porteurs de strongles avec une prévalence de 100ù pour les bovins et les chèvres et 95% chez les moutons. [...]TOULOUSE-ENSAT-Documentation (315552324) / SudocSudocFranceF

Multiple Pathogens Including Potential New Species in Tick Vectors in Cote d'Ivoire

International audienceBackground Our study aimed to assess the presence of different pathogens in ticks collected in two regions in Cote d'Ivoire. Methodology/Principal Findings Real-time PCR and standard PCR assays coupled to sequencing were used. Three hundred and seventy eight (378) ticks (170 Amblyomma variegatum, 161 Rhipicepalus microplus, 3 Rhipicephalus senegalensis, 27 Hyalomma truncatum, 16 Hyalomma marginatum rufipes, and 1 Hyalomma impressum) were identified and analyzed. We identified as pathogenic bacteria, Rickettsia africae in Am. variegatum (90%), Rh. microplus (10%) and Hyalomma spp. (9%), Rickettsia aeschlimannii in Hyalomma spp. (23%), Rickettsia massiliae in Rh. senegalensis (33%) as well as Coxiella burnetii in 0.2%, Borrelia sp. in 0.2%, Anaplasma centrale in 0.2%, Anaplasma marginale in 0.5%, and Ehrlichia ruminantium in 0.5% of all ticks. Potential new species of Borrelia, Anaplasma, and Wolbachia were detected. Candidatus Borrelia africana and Candidatus Borrelia ivorensis (detected in three ticks) are phylogenetically distant from both the relapsing fever group and Lyme disease group borreliae; both were detected in Am. variegatum. Four new genotypes of bacteria from the Anaplasmataceae family were identified, namely Candidatus Anaplasma ivorensis (detected in three ticks), Candidatus Ehrlichia urmitei (in nine ticks), Candidatus Ehrlichia rustica (in four ticks), and Candidatus Wolbachia ivorensis (in one tick). Conclusions/Significance For the first time, we demonstrate the presence of different pathogens such as R. aeschlimannii, C. burnetii, Borrelia sp., A. centrale, A. marginale, and E. ruminantium in ticks in Cote d'Ivoire as well as potential new species of unknown pathogenicity

23S rRNA based phylogenetic analysis of strains identified in this study.

<p>Phylogenetic tree highlighting the position of <i>Anaplasma</i> sp, <i>Ehrlichia</i> sp and <i>Wolbachia</i> sp identified in the present study relative to <i>Anaplama</i>, <i>Ehrlichia</i> and <i>Wolbachia</i> type and uncultured strains. The 23S rRNA sequences were aligned using MEGA 6 and phylogenetic inferences were obtained from a Bayesian phylogenetic analysis with the HKY standard model.</p

Map of Côte d’Ivoire showing the regions, cities and villages where the ticks were collected for our study.

<p>Map of Côte d’Ivoire showing the regions, cities and villages where the ticks were collected for our study.</p

<i>flaB</i> gene-based phylogenetic analysis of the strains identified in this study.

<p>Phylogenetic tree highlighting the position of <i>Borrelia</i> sp. identified in the present study relative to <i>borrelia</i> type strains and uncultured borreliae. The <i>flaB</i> sequences were aligned using CLUSTALW, and phylogenetic inferences were obtained from a Bayesian phylogenetic analysis with the HKY+Γ; JC+ Γ and HKY+ Γ substitution models for the first, second and third codons respectively. The GenBank accession numbers are indicated at the end. Sequences obtained in the present study are in bold. The numbers at the nodes are the bootstrap values obtained by repeating the analysis 100 times to generate a majority consensus tree. There were a total of 300 positions in the final dataset. The scale bar indicates a 10% nucleotide sequence divergence.</p

Melioidosis in Africa: Time to Uncover the True Disease Load

Melioidosis is an often fatal infectious disease with a protean clinical spectrum, caused by the environmental bacterial pathogen Burkholderia pseudomallei. Although the disease has been reported from some African countries in the past, the present epidemiology of melioidosis in Africa is almost entirely unknown. Therefore, the common view that melioidosis is rare in Africa is not evidence-based. A recent study concludes that large parts of Africa are environmentally suitable for B. pseudomallei. Twenty-four African countries and three countries in the Middle East were predicted to be endemic, but no cases of melioidosis have been reported yet. In this study, we summarize the present fragmentary knowledge on human and animal melioidosis and environmental B. pseudomallei in Africa and the Middle East. We propose that systematic serological studies in man and animals together with environmental investigations on potential B. pseudomallei habitats are needed to identify risk areas for melioidosis. This information can subsequently be used to target raising clinical awareness and the implementation of simple laboratory algorithms for the isolation of B. pseudomallei from clinical specimens. B. pseudomallei was most likely transferred from Asia to the Americas via Africa, which is shown by phylogenetic analyses. More data on the virulence and genomic characteristics of African B. pseudomallei isolates will contribute to a better understanding of the global evolution of the pathogen and will also help to assess potential differences in disease prevalence and outcome