ABSTRACT
ABSTRACT Stomoxys Geoffroy, 1762 are major livestock pests in the tropics and are common in diverse habitats. This study aims to conduct a survey on the Stomoxys fauna of Cameroon. From 2015 to 2017, entomological studies using standard traps (n=204) were conducted in eight administrative regions found in five agro-ecological zones (AEZs) of Cameroon with 606 trap-points over 22,032 traps days. A total of 77,804 Stomoxys specimens were collected, with eight taxa consisting of six species (S. calcitrans (Linnaeus, 1758), S. omega Newstead, Dutton & Todd, 1907, S. xanthomelas Roubaud, 1937, S. inornatus Grunberg, 1906, S. transvittatus Villeneuve, 1916, and S. sitiens (Rondani, 1873)) and two subspecies (Stomoxys niger niger Macquart, 1851 and S. niger bilineatus Grunberg, 1906) identified. Among all the recorded taxa, S. calcitrans and S. n. niger were present in five and seven of the eight regions respectively, but S. sitiens was rare and only found in the North. Furthermore, the highest species number (seven out of eight) was recorded in the Guinee savanna of the Adamawa region. The highest apparent density range of 101 to 200 Stomoxys/ trap/ day (s/t/d) was recorded in the Sudan savanna AEZ of the Far North region. Stomoxys occurred in all the AEZs in eight regions, some of which are major cattle rearing regions. This represents risk for the mechanically transmission of dangerous pathogens in those regions.
ABSTRACT
The role of tabanids as potential transmitters of animal trypanosomiasis (AAT) has not yet been established in Cameroon. The objectives of this study were: (i) to trap and determine the species richness and abundance of tabanids, (ii) to identify circulating trypansomes in cattle and tabanids in a tsetse free area. A three year (2015 to 2017) tabanid survey in six regions of Cameroon was conducted. In Galim village, which is in a tsetse free area, both tabanids and cattle blood samples were screened by PCR for the presence of trypanosome DNA. Tabanids were diverse in Littoral (13 species) and in Adamawa (13 species), but were abundant in the Far North region (36.37 to 145.58 tabanids per trap per day (t/t/d)). In Galim, the tabanid trypanosomal DNA presence was 24.4% (95% CI: 11.25-37.53), while the bovine trypanosomal DNA presence was 4.8% (95% CI: 1.68-11.20). In this village, the Trypanosoma spp. identified in tabanids were T. theileri, T. vivax and T. evansi, while those in cattle were T. theileri and T. vivax. The control of tabanids is required to stop the mechanical spread of AAT in tsetse free areas.
ABSTRACT
In recent years, an upsurge of vector-borne diseases has been reported in several parts of the world. Among these is dengue fever, the first arbovirus transmitted by mosquitoes of the genus Aedes. After the detection of the dengue virus serological types (type 1, 2, and 3) in the health district of Cocody-Bingerville in Ivory Coast, entomological investigations were carried out in the city of Cocody (host of most cases) to evaluate the risk of transmission of the disease in view of an effective vector control. Larval prospection together with the pitching of emergence traps was carried out in Caféier 5, Sideci-Coteau, Danga, Ecole de police, Gobelet village, Laurier 9, Lemania, Perles, 7ème tranche, and 12ème arrondissement. Entomological prospections revealed the predominance of Aedes aegypti (97.38%) as the main vector species of dengue viruses in Cocody. The Kruskall-Wallis test showed no statistically significant difference (KW = 1.8, p = 0.407) in the proportions of the vector species collected from the sampled sites. The risk of an outbreak of dengue fever in Cocody and other municipalities in the city of Abidjan is very certain insofar as the larval epidemic risk indices (Habitat Index, HI = 70.9; Container Index, CI = 40.26; and Breteau Index, BI= 21.3) reflect a very high epidemic risk (4 to 9) on the WHO density scale. The occurrence of Aedes aegypti in Cocody indicates the risk of transmission of the Dengue fever virus.
