Species identity and phylogeny of Paramphistomoidea Fischoeder, 1901 occurring in cattle and sheep in North Cameroon.

Paramphistomidae and Gastrothylacidae are parasitic flatworms occurring in wild and domestic ruminants in different parts of the world especially in Asia and Africa. In Central Africa, few studies have been done using molecular techniques to resolve taxonomical groupings and understand the epizootiology of these parasites. In this study, we molecularly characterized two hundred adult flukes collected from the fore stomachs of cattle and sheep in the Adamawa region of the northern Cameroon. PCR and sequencing of the nuclear ITS-2 of the ribosomal DNA gene and a portion of the mitochondrial cox-1 locus revealed the presence of at least nine species belonging to the genera of Cotylophoron, Calicophorn, Orthocoelium and Carmyerius. In Zebu cattle, we identified Ca. microbothrium, Ca. clavula, Ca. phillerouxi, Co. cotylophorum, Co. fuelleborni, O. scoliocoelium, Car. gregarius, Car. graberi and Car. mancupatus and one yet unknown Paramphistomoidea sp, whereas in sheep, only Ca. microbothrium was found. The present study also strongly suggests cross-hybridization between the two Cotylophoron species coexisting in cattle. These results have implications for the diagnosis and control of rumen flukes in the region and point to the need for accurate species identification to understand parasite distribution and population genetics.

Ticks and Rickettsiae Associated with Wild Animals Sold in Bush Meat Markets in Cameroon.

Ticks are obligate blood-sucking parasites of wild animals and transmit many zoonotic microorganisms that can spread to domesticated animals and then to humans. In Cameroon, little is known about tick diversity among wildlife, especially for animals which are hunted for human consumption. Therefore, this survey was undertaken to investigate tick and Rickettsia species diversity parasitizing the wild animals sold in bush meat markets in Cameroon. In total, 686 ticks were collected and identified to the species level based on morphology, and some were genetically analyzed using the 16S rRNA gene. Eighteen tick species belonging to five genera were identified: Amblyomma spp. (Amblyomma compressum, Amblyomma flavomaculatum, and Amblyomma variegatum), Haemaphysalis spp. (Haemaphysalis camicasi, Haemaphysalis houyi, Haemaphysalis leachi, and Haemaphysalis parmata), Hyalomma spp. (Hyalomma nitidum, Hyalomma rufipes, and Hyalomma truncatum), Ixodes spp. (Ixodes rasus and Ixodes moreli), and Rhipicephalus spp. (Rhipicephalus guilhoni, Rhipicephalus moucheti, Rhipicephalus muhsamae, Rhipicephalus microplus, Rhipicephalus camicasi, and Rhipicephalus linnaei). In terms of Rickettsia important for public health, two Rickettsia spp., namely Rickettsia aeschlimannii and Rickettsia africae, were detected in Hyalomma spp. and Amblyomma spp., respectively. Distinct tick-pathogen patterns were present for divergent sequences of R. africae associated with exclusively A. variegatum vectors (type strain) versus vectors comprising A. compressum, A. flavomaculatum, and A. variegatum. This suggests possible effects of vector species population dynamics on pathogen population circulation dynamics. Furthermore, Candidatus Rickettsia africaustralis was detected for the first time in Cameroon in I. rasus. This study highlights the high diversity of ticks among wildlife sold in bush meat markets in Cameroon.

Testing the susceptibility of larval stages of Simulium to temephos and Bacillus thuringiensis var israelensis in Germany and Northern Cameroon.

Assays to evaluate the susceptibility of Simulium larvae to temephos and Bacillus thuringiensis var israelensis (Bti) were carried out by setting-up an in vitro laboratory test ('bio assay') and a semi-natural test ('système de goutières') to assess the LC50/LC90 values. Larvae of Simulium species in Cameroon (S. damnosum s.l., S. hargreavesi, S. vorax and S. cervicornutum) and (S. (Odagmia) ornatum and S. latipes) in Germany were identified and tested. In the bio-assay, 50 larvae were exposed for 10 min to concentrations from 0.01 to 10 ppm. For the Simulium from Germany, the LC50 (LC90) values after 3 and 6 h were 3.1 (27.9) and 0.14 (1.26) ppm for temephos and for Bti 7.8 (70.2) and 1.7 (15.3) ppm, respectively. For Cameroonian species, the values of LC50 (LC90) were lower, that is, 0.42 (8.04), 0.14 (2.70) and 0.073 (1.38) ppm, respectively, after 3, 6 and 12 h for temephos. In a semi natural condition, the LC50 of 10 min of application of temephos was 0.84 ppm after 3 h and a working solution (2.6 L) of Bti killed 50% after 6 h. To detect an upcoming of any resistance as it happened in Ivory Coast, a study of the occurrence resistance genes should be implemented.