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Visceral leishmaniasis is not endemic in West Africa, but prevalence of canine leishmaniasis and seroprevalence of Leishmania infantum infection in humans are high in the Mont Rolland community (Thiès region, Senegal). Previous studies in this area showed that Sergentomyia schwetzi could be the potential vector of Le. infantum. To precisely describe the biology and population structure of this potential vector, we identified eight novel microsatellite loci to characterize Se. schwetzi populations. We tested these loci in Se. schwetzi populations from five locations at Mont Rolland (Thiès, Senegal). All the loci were polymorphic, with a mean of 17.25 alleles (observed heterozygosity: 0.455). We did not detect any evidence of scoring errors due to stuttering and large allele dropout. Moreover, several of these loci were also amplified in six other sand fly species (Sergentomyia magna, Sergentomyia dubia, Sergentomyia minuta, Phlebotomus duboscqi, Phlebotomus perniciosus, and Phlebotomus ariasi). These preliminary results demonstrate the utility of these microsatellite markers for Se. schwetzi (and for the other sand fly species) population genetic studies.

In recent years, photovoltaic (PV) modules are widely used in many applications around the world. However, this renewable energy is plagued by dust, airborne particles, humidity, and high ambient temperatures. This paper studies the effect of dust soiling on silicon-based photovoltaic panel performance in a mini-solar power plant located in Dakar (Senegal, 14°42'N latitude, 17°28'W longitude). Results of the current-voltage (I - V) characteristics of photovoltaic panels tested under real conditions. We modeled a silicon-based PV cell in a dusty environment as a stack of thin layers of dust, glass and silicon. The silicon layer is modeled as a P-N junction. The study performed under standard laboratory conditions with input data of irradiation at 1000 W/m2, cell temperature at 25°C and solar spectrum with Air Mass (AM) at 1.5 for the monocrystalline silicon PV cell (m-Si). The analysis with an ellipsometer of dust samples collected on photovoltaic panels allowed to obtain the refraction indices (real and imaginary) of these particles which will complete the input parameters of the model. Results show that for a photon flux arriving on dust layer of 70 μm (corresponding to dust deposit of 3.3 g/m2) deposited on silicon-based PV cells, short circuit current decreases from 54 mA (for a clean cell) to 26 mA. Also, conversion efficiency decreases by 50% compared to clean cell and the cell fill factor decreases by 76% - 50% compared to reference PV cell.

The objective of this work is to evaluate the available solar potential at N’Djamena (12°08N, 15°04E) from 2017 to 2018. To achieve this goal, we used various datasets and model including: the in situ shortwave radiation (by pyranometer) measurement and sunshine duration (by Campbell-Stokes heliograph) obtained from N’Djamena station, observations from MODIS (aerosol optical depth (AOD) and precipitable water) satellite sensors, and simulations from Streamer radiative code. The results show the presence of a good available solar potential with an annual global potential of 4.71 kWh/m2/d. At the intra-seasonal time scale, there are two maximums for the global solar potential. The first maximum is registered in the month of March (spring) with value of 5.7 kWh/m2/d and the second in October (autumn) with value of 5.18 kWh/m2/d. However, the minimum of global potential is recorded in winter (from December to February) with values around 3.86 kWh/m2/d. Then, the measured global irradiation allowed validating the Streamer radiative transfer code with a score of more than 98%. Subsequently, this model was used to simulate direct normal and diffuse irradiation for several types of days (clear, dusty and cloudy days). An examination of the dust influence on solar radiation based on selected cases (AOD = 2.05) indicates a mean decrease of 3.33 and 3.17 kWh/m2/d, respectively, for the total and direct normal potential. This corresponds to an increase of the diffuse potential of 0.52 kWh/m2/d. Finally, an increase of 5.82 cm of precipitable water per day tends to decrease the overall potential of 0.73 kWh/m2/d and the direct normal potential of 1.74 kWh/m2/d. For this cloudy day, the potential has increased more than 0.89 kWh/m2/d.

The African fauna of the rare family of parasitoid wasps, Orussidae, is reviewed. Five genera with 24 valid species are recognized. Chalinus davidi Vilhelmsen n. sp. is described; the male of Chalinus albitibialis Vilhelmsen, 2005, the male of Leptorussus madagascarensis Vilhelmsen, 2007 and the female of Orussus smithi Blank et al., 2006 are described. A neotype is designated for Oryssus plumicornis Guerin-Meneville, [1849] to properly define the genus-group name Chalinus Konow, 1897. Chalinus braunsi (Enslin, 1911), C. orientalis Guiglia, 1937 and C. somalicus Guiglia, 1935 are regarded as new junior synonyms of C. plumicornis. Leptorussus kwazuluensis Vilhelmsen, 2003 is regarded as a new junior synonym of L. africanus Benson, 1955. Distribution records for specimens examined by us are listed. The Afrotropical component of the African orussid fauna shows a high degree of endemism, with two endemic genera and 13 endemic species; only Chalinus timnaensis Kraus, 1998 and Pseudoryssus niehuisorum...

In January 2014, individuals of Diadegma insulare (Cresson) (Hymenoptera: Ichneumonidae: Campopleginae) were collected in farmers' fields on Brassica oleracea L. (Brassicaceae) at Dalifort (14°44'35.06"N 17°24'41.67"W) and Maristes (14°44'16.54"N 17°26'02.96"W). This is the first record of this parasitoid from Senegal and West Africa. In 2015, several specimens were collected in another locality called Gorom (14°49'29.6"N 17°09'14.38"W), as well as from Mboro (15°08' 32.54"N 16°52'58.08"W) in January 2016 when some individuals were found on farmers' cabbage crop. Currently, according to these observations, it seems that this species is moving to the north of the Niayes coastal area. Some specimens were deposited in France in the private collection of P. Rousse, an international taxonomist, who specialises in Campopleginae and who works in the French Agricultural Centre for International Development (CIRAD, France). He identified the species using the key proposed by Azidah et al.

Visceral leishmaniasis is not endemic in West Africa. However, high seroprevalence of Leishmania infantum infection (one of the Leishmania species that cause visceral leishmaniasis) was detected in dogs and humans in the Mont Rolland community (close to Thiès, Senegal), despite the lack of reports concerning human clinical cases. Our aim was to genetically characterize this L. infantum population and identify its origin. We thus conducted seven field surveys in 25 villages of the Mont Rolland community between 2005 and 2009 and blood samples were collected from 205 dogs. Serological testing indicated that 92 dogs (44.9%) were positive for Leishmania infection. L. infantum was identified as the cause of infection. Analysis of 29 L. infantum isolates from these dogs by multilocus microsatellite typing and multilocus sequence typing indicated that this population had very limited genetic diversity, low level of heterozygosity and only seven different genotypes (79.3% of all isolates had the same genotype). Multilocus sequence typing showed that the Mont Rolland isolates clustered with strains from the Mediterranean basin and were separated from East African and Asian strains. Therefore, our data suggest a quite recent and unique introduction into Senegal of a L. infantum strain from the Mediterranean basin.

Whereas Leishmania infantum, the agent of visceral leishmaniasis (VL), is well known in North Africa, very limited data exist on its spread in West Africa, where mainly cutaneous leishmaniasis has been widely reported. Nevertheless, dogs infected with L. infantum were recently found in the Mont Rolland District in Senegal. To provide a better understanding of L. infantum epidemiology in this area, clinical and serological surveys were carried out to determine the seroprevalence of L. infantum-specific antibodies in the human population. In parallel, an analysis of environmental and individual factors associated with Leishmania antigen seropositivity was conducted to identify potential risk factors for exposure. Although no cases of VL were detected within this study, a large part of the population (73/315; 23%) was exposed to infection, with a strong age effect (being >40 years old increased the risk of being seropositive). Moreover, the presence of Nebedaye trees (Moringa oleifera) and infected dogs in the household were factors increasing the risk of exposure in household members. These results may provide important information to identify the still unknown sandfly species involved in transmission.

Leishmania (L.) infantum is the causative agent in an endemic focus of canine leishmaniasis in the Mont-Rolland district (Thiès, Senegal). In this area, the transmission cycle is well established and more than 30% of dogs and 20% of humans are seropositive for L. infantum. However, the sand fly species involved in L. infantum transmission cycle are still unknown. Between 2007 and 2010, 3654 sand flies were collected from different environments (indoor, peridomestic, farming and sylvatic areas) to identify the main L. infantum vector(s). Nine sand fly species were identified. The Phlebotomus genus (n = 54 specimens; Phlebotomus (Ph) duboscqi and Phlebotomus (Ph). rodhaini) was markedly under-represented in comparison to the Sergentomyia genus (n = 3600 specimens; Sergentomyia (Se) adleri, Se. clydei, Se. antennata, Se. buxtoni, Se. dubia, Se. schwetzi and Se. magna). Se. dubia and Se. schwetzi were the dominant species indoor and in peridomestic environments, near humans and dogs. Blood-meal analysis indicated their anthropophilic behavior. Some Se. schwetzi specimens fed also on dogs. The dissection of females in the field allowed isolating L. infantum from sand flies of the Sergentomyia genus (0.4% of Se. dubia and 0.79% of Se. schwetzi females). It is worth noting that one Se. dubia female not engorged and not gravid revealed highly motile metacyclic of L. infantum in the anterior part of the midgut. PCR-based diagnosis and sequencing targeting Leishmania kinetoplast DNA (kDNA) highlighted a high rate of L. infantum-positive females (5.38% of Se. dubia, 4.19% of Se. schwetzi and 3.64% of Se. magna). More than 2% of these positive females were unfed, suggesting the parasite survival after blood-meal digestion or egg laying. L. infantum prevalence in Se. schwetzi was associated with its seroprevalence in dogs and humans and L. infantum prevalence in Se. dubia was associated with its seroprevalence in humans. These evidences altogether strongly suggest that species of the Sergentomyia genus are probably the vectors of canine leishmaniasis in the Mont-Rolland area and challenge one more time the dogma that in the Old World, leishmaniasis is exclusively transmitted by species of the Phlebotomus genus., Author Summary Leishmaniases, neglected tropical vector-borne diseases, remain today a problem of public health. Classically, the sand flies involved in Leishmania transmission belong either to the Phlebotomus genus (Old World) or to the Lutzomyia genus (New World). In the rural community of Mont-Rolland (Senegal, West Africa), Leishmania infantum is the causative agent in an endemic focus of canine leishmaniasis. Recent surveys revealed more than 30% of dogs and 20% of humans with a positive serological test for Leishmania in this community. However, the sand fly species involved in L. infantum transmission were still unknown. Between 2007 and 2010, we carried out a study in this community to identify the sand fly species responsible for L. infantum transmission. We collected nine species belonging mainly to Sergentomyia genus and in low proportion to Phlebotomus genus. The abundance around dogs and humans, the detection of live and mature parasites in anterior midgut, the high rate of L. infantum-positive females using molecular analyses and the identification of dog and human blood in the fed females incriminates Se. schwetzi and Se. dubia as possible vectors of L. infantum. This hypothesis is strongly supported by statistical analyses performed to compare the prevalence of infected sand flies with the seroprevalence data in humans and dogs.

Phlebotomine sandflies of Senegal. First description of the male of Sergentomyia (Sintonius) herollandi Ábonnenc, 1960, and redescription of the female (Diptera, Psychodidae). Six males were recorded around Kedougou, eastern Senegal, with females of Sergentomyia herollandi Abonnenc, 1960, whose male was not identified so far. The survey and description of these specimens reveal, among all specific characters, the presence of many denticles forward and on main tooth sides, of a small and cone-shaped pigmented patch, of short spines on the posterior femurs. These characters are found on females of S. herollandi, so we link up these males to this species., Six mâles ont été capturés aux alentours de Kédougou, Sénégal oriental, en compagnie de femelles de Sergentomyia herollandi Abonnenc, 1960, dont le mâle était jusque-là inconnu. L'étude et la description de ces spécimens révèlent, entre autres caractères spécifiques, la présence de nombreux denticules en avant et sur les côtés des dents principales, d'une petite plage pigmentée en forme de cône, d'épines courtes sur les fémurs postérieurs. Ces caractères sont rencontrés chez les femelles de S. herollandi , en conséquence, nous rattachons ces mâles à cette espèce., Niang Abdoul Aziz, Ba Yamar, Trouillet Jean, Fontenille Didier. Phlébotomes du Sénégal. Première description du mâle de Sergentomyia (Sintonius) herollandi Abonnenc, 1960, et redescription de la femelle (Diptera, Psychodidae). In: Bulletin de la Société entomologique de France, volume 107 (4), octobre 2002. pp. 429-433.

Phlebotomine sandflies of Senegal : new morphological data on the female of Sergentomyia (Sintonius) edentulus Pastre, 1982 and first description of the male (Diptera, Psychodidae). Captures of Phlebotomine sandflies were made near Kedougou, in Eastern Senegal. New data on morphology of the female of Sergentomyia (Sintonius) edentulus Pastre, 1982 are presented. The male is described for first time., De nouvelles données sont apportées sur la morphologie de la femelle de Sergentomyia (Sintonius) edentulus Pastre, 1982. Le mâle, jusqu'alors inconnu, est décrit. Les captures ont été effectuées dans la région de Kédougou au Sénégal oriental., Trouillet Jean, Ba Yamar, Niang Abdoul Aziz, Fontenille Didier. Phlébotomes du Sénégal : nouvelles données sur la morphologie de la femelle de Sergentomyia (Sintonius) edentulus Pastre, 1982 et première description du mâle (Diptera, Psychodidae). In: Bulletin de la Société entomologique de France, volume 102 (3), août 1997. pp. 299-304.

A management program of biodiversity inventory and conservation was recently adopted for the rehabilitation of the Madeleine Island National Park (MINP). Entomological surveys were conducted between 2006 and 2009 to gather biological data on the biodiversity and to point out species of interest. Over 30 species of insects belonging mainly to Coleoptera, Orthoptera and Lepidoptera were collected and identified. The Baobab is one of the most important tree species of interest due to its dwarfism which is a source of curiosity for many scientists, visitors and tourists. A coleopteran pest Analeptes trifasciata (Cerambycidae) was found to be a vicious pest to the Baobab Adansonia digitata (Malvale: Bombacaceae). That Beetle was reported earlier in almost all West African countries as a threat to many tree species. This preliminary survey encourages a thorough inventory of the biodiversity and suggests a conservation strategy for major species such as the Baobab, by introducing a management tool to control the damages of A. trifasciata.

Background Different epidemiological studies previously indicated that canine leishmaniasis is present in the region of Thies (Senegal). However, the risks to human health, the transmission cycle and particularly the implicated vectors are unknown. Methodology/Principal Findings To improve our knowledge on the population of phlebotomine sand flies and the potential vectors of canine leishmaniasis, sand flies were collected using sticky traps, light traps and indoor spraying method using pyrethroid insecticides in 16 villages of the rural community of Mont Rolland (Thies region) between March and July 2005. The 3788 phlebotomine sand flies we collected (2044 males, 1744 females) were distributed among 9 species of which 2 belonged to the genus Phlebotomus: P. duboscqi (vector of cutaneous leishmaniasis in Senegal) and P. rodhaini. The other species belonged to the genus Sergentomyia: S. adleri, S. clydei, S. antennata, S. buxtoni, S. dubia, S. schwetzi and S. magna. The number of individuals and the species composition differed according to the type of trap, suggesting variable, species-related degrees of endophily or exophily. The two species of the genus Phlebotomus were markedly under-represented in comparison to the species of the genus Sergentomyia. This study also shows a heterogeneous spatial distribution within the rural community that could be explained by the different ecosystems and particularly the soil characteristics of this community. Finally, the presence of the S. dubia species appeared to be significantly associated with canine leishmaniasis seroprevalence in dogs. Conclusions/Significance Our data allow us to hypothesize that the species of the genus Sergentomyia and particularly the species S. dubia and S. schwetzi might be capable of transmitting canine leishmaniasis. These results challenge the dogma that leishmaniasis is exclusively transmitted by species of the genus Phlebotomus in the Old World. This hypothesis should be more thoroughly evaluated.

In the context of global warming and the risk of spreading arthropod-borne diseases, the emergence and reemergence of leishmaniasis should not be neglected. In Senegal, over the past few years, cases of canine leishmaniasis have been observed. We aim to improve the understanding of the transmission cycle of this zoonosis, to determine the responsible species and to evaluate the risk for human health. An epidemiological and serological study on canine and human populations in the community of Mont Rolland (Thies area) was conducted. The data showed a high seroprevalence of canine leishmaniasis (>40%) and more than 30% seropositive people. The dogs' seroprevalence was confirmed by PCR data (concordance > 0.85, Kappa > 0.7). The statistical analysis showed strong statistical associations between the health status of dogs and seropositivity, the number of positive PCRs, clinical signs and the number of Leishmania isolates. For the first time, the discriminative PCRs performed on canine Leishmania strains clearly evidenced that the pathogenic agent is Leishmania infantum. The results obtained show that transmission of this species is well established in this area. That the high incidence of seropositivity in humans may be a consequence of infection with this species is discussed. Published by Elsevier Masson SAS on behalf of the Institut Pasteur.

Control of fruit flies, Didacus spp. on cucurbits in Senegal (Diptera, Tephritidae). Considering the importance of the damage caused to crops by the fruit flies, chemical and natural insecticides were compared on melon. For chemical control, results obtained revealed that dimethoate 400 g a.i./l was ineffective against the pests. This inefficacy is probably related to successive and frequent applications of the product in the field possibly causing the insects to be used to it. Alphacypermethrin 50 g a.i./l, Deltamethrin 25g a.i./l, Cypermethrin 200 g a.i ./l, Fenthion 50 g a.i./l, Trichlorfon 95 g a.i./l and the following mixtures : Deltamethrin 25 g a.i./l / Dimethoate 400 g a.i./l, Cypermethrin 30 g a.i./l / Chlorpyriphos Ethyl 150 g a.i./l / Fenobucarb 150 g a.i./l and Cypermethrin 42 g a.i./l / Malathion 400 g a.i./l were very effective against the flies. Yields were 2 to 3 times more in these treatments when compared to the untreated control. Treatment with Azadirachta indica (15 g a.i./l and 30 g a.i./l), Pachyrrhizus erosus (90 g a.i./l) and Procur (50 cc / 200 1) showed that these natural products could constitute a better alternative to chemicals considering the danger the latter pose to man and the environment., Vu l'importance des pertes de récoltes causées par les mouches des Cucurbitacées, Didacus spp., des essais de comparaison de protections par des insecticides chimiques et naturels ont été effectués sur des cultures de melon. Dans la lutte chimique, les résultats obtenus ont révélé le manque d'efficacité du Dimé-thoate 400 g m.a./l dans le contrôle des ravageurs. Cette absence de protection satisfaisante est probablement liée aux applications répétées d'une manière intempestive du produit sur les cultures ; ceci engendre une accoutumance ou peut-être la résistance des ravageurs à ce produit. L'Alphacyperméthrine 50 g m.a./l, la Deltaméthrine 25 g m.a./l, la Cyperméthrine 200 g m.a./l, le Fenthion 50 g m.a./l, le Trichlorfon 95 g m.a./l et les produits associant Deltaméthrine 25 g m.a./l / Diméthoate 400 g m.a./l, Cyperméthrine 30 g m.a./l / Chlorpyriphos éthyl 150 g m.a./l / Fenobucarb 150 g m.a./l et Cyperméthrine 42 g m.a./l / Malathion 400 g m.a./l se sont montrés actifs. Ils ont permis d'obtenir au moins 2 à 3 fois plus de rendement que le témoin non traité. Azadirachta indica (15 g m.a./l et 30 g m.a./l), Pachyrrhizus erosus (90 g m.a./l) et le Procur (50 cc / 200 1) ont montré que la protection avec les produits naturels pourrait constituer une meilleure alternative à la lutte chimique, vu le caractère néfaste de celle-ci pour l'Homme et son environnement., Badji Hawa, Coly Emile victor, Han Sun heat, Niang Abdoul Aziz. Lutte contre les mouches des Cucurbitacées, Didacus spp. au Sénégal (Díptera, Tephritidae). In: Bulletin de la Société entomologique de France, volume 106 (2), juin 2001. pp. 181-191.