Molecular prevalence, genetic characterization and patterns of Toxoplasma gondii infection in domestic small mammals from Cotonou, Benin

Toxoplasmosis, one of the most prevalent parasitic infections in humans and animals, is caused by the intracellular protozoan parasite Toxoplasma gondii. Small mammals play a key role as intermediate reservoir hosts in the maintenance of the T. gondii life cycle. In this study, we estimated the molecular prevalence and provide genetic diversity data for T. gondii in 632 small mammals sampled in four areas of Cotonou city, Benin. Both the brain and heart of each individual were screened through T. gondii-targeting qPCR, and positive samples were then genotyped using a set of 15 T. gondii-specific microsatellites. Prevalence data were statistically analyzed in order to assess the relative impact of individual host characteristics, spatial distribution, composition of small mammal community, and urban landscape features. An overall T. gondii molecular prevalence of 15.2% was found and seven genotypes, all belonging to the Africa 1 lineage, could be retrieved from the invasive black rat Rattus rattus and the native African giant shrew Crocidura olivieri. Statistical analyses did not suggest any significant influence of the environmental parameters used in this study. Rather, depending on the local context, T. gondii prevalence appeared to be associated either with black rat, shrew, or mouse abundance or with the trapping period. Overall, our results highlight the intricate relationships between biotic and abiotic factors involved in T. gondii epidemiology and suggest that R. rattus and C. olivieri are two competent reservoirs for the Africa 1 lineage, a widespread lineage in tropical Africa and the predominant lineage in Benin

Two new African siblings of Pulveroboletus ravenelii (Boletaceae)

This paper sorts out the taxonomy of species affiliated with Pulveroboletus ravenelii in the Guineo-soudanian and Zambezian woodlands of Africa. Morphological and genetic characters of African Pulveroboletus collections were studied and compared to those of North American and Asian species. A phylogenetic analysis showed that the African specimens form a subclade, sister to the Asian and American taxa. Although clamp connections have previously never been reported from Pulveroboletus, all specimens of the African subclade show very small clamp connections. Two new African species, Pulveroboletus africanus sp. nov. and P. sokponianus sp. nov., are described and illustrated. Comments concerning morphology and identification, as well as distribution and ecology, are given for both species

Paxilloboletus gen. nov., a new lamellate bolete genus from tropical Africa

This study presents Paxilloboletus gen. nov., a new lamellate bolete genus represented by two tropical African species, Paxilloboletus africanus sp. nov. and Paxilloboletus latisporus sp. nov. Although the new taxa strongly resemble Paxillus (Paxillaceae), they lack clamp connections and form a separate generic clade within the Boletaceae phylogeny. The new species are lookalikes, morphologically only separable by their spore morphology. Descriptions and illustrations of the new genus and new species are given, as well as comments on ecology, distribution, and morphological differences with other gilled Boletaceae

ObsMICE: a monitoring system to assess long-term changes in biodiversity of small mammals and associated parasites in a broad range of West African ecosystems

International audienc

Maritime international trade and bioinvasions: A three‐year long survey of small mammals in Autonomous Port of Cotonou, Benin

International audience1. International trade has been favouring the dissemination of a wide suite of invasive alien species. Upstream prevention through the monitoring of entry points is identified as an appropriate strategy to achieve control of bioinvasions and their consequences. Maritime transportation has been responsible for the introduction worldwide of exotic rodents that are major pests for crops and food stocks as well as reservoirs of many zoonotic pathogens. In order to limit further dissemination, the International Health Regulation constrains decisions makers and socio-economic stakeholders to manage ship-mediated import/export of rodents within seaports.2. Unfortunately, eco-evolutionary insights into rodent introduction events that could guide preventive actions in seaports are very scarce. In order to bridge this gap, we here describe the results of a 3 year-long survey of small mammals conducted in the Port of Cotonou, Benin.3. Our aim was to assess the spatiotemporal distribution, diversity and relative abundance of invasive and native rodents.4. 960 small mammal individuals were captured in nine within-seaport sites. We found (i) a marked predominance of invasive species (84% of the individuals belonging to Mus musculus, Rattus rattus, R. norvegicus), (ii) with native species (i.e. Mastomys natalensis and the shrew Crocidura olivieri) essentially restricted to peripheral non-industrial areas, as well as (iii) a fine-scale spatial segregation stable over time between the invasive Norway rats and house mice on the one hand, and the black rats and shrews on the other hand.5. Furthermore, trapping before and after two successive rodent control campaigns indicates that they were ineffective and that subsequent rodent recolonisation occurred 6–12 months following intervention.6. Synthesis and applications. Our results are discussed in terms of ecological processes at play (e.g. interspecific interactions) and operational recommendations (e.g. assessment of proper eradication units, environmental modifications)

Prolifération de rongeurs dans les milieux urbains et agricoles d’Afrique subsaharienne: Le côté obscur des rodenticides chimiques de synthèse

Nous tenons à remercier Valérie Golaz (INED-LPED), Marc Egrot (IRD-LPED) et les organisateurs de la conférence internationale « Mise en œuvre des politiques publiques et pesticides dans les Suds » qui s’est tenue en octobre 2021 à Bouaké, Côte d’Ivoire, projet PoPPesCI (Politiques publiques et pesticides en agriculture urbaine), pour avoir stimulé la rédaction de cet article.International audienceAround 400 million people in the world are affected by zoonoses associated with rodents. In addition, at least 280 million cases of undernourishment could be avoided in the world by the effective management of populations of rodents which destroy crops and stores of crops. Consequently, managing rodent populations which are reservoirs of pathogenic agents or which destroy crops and stores of crops is a challenge both in terms of food security as well as public health. In terms of public policy, many African countries have established farming intensification programmes aiming to improve their food self-sufficiency, with the direct risk of the prolifera-tion of rodents. In this article, which is the first in a two-part series, we present the background to controlling rodents in Africa in rural and urban areas, followed by an overview of the regu-lations and uses of rodenticides. We will go on to document the problematic situations which result from this, illustrating them with case studies. The use of synthetic chemical rodenticidesis the most widely used method to control rodents and is not only toxic for humans, other animals and the environment, but also ineffective against rodent populations (for example, it is costly, leads to a build-up of resistance, and the avoidance of bait). The circulation and uncontrolled use of these rodenticides in many African countries is associated with conside-rable risks to health and the environment, without leading to any significant improvements in terms of rodent control or reducing the damage they cause.Dans le monde, environ 400 millions de personnes sont touchées chaque année par des zoonoses associées aux rongeurs. En outre, au moins 280 millions de cas de sous-alimentation pourraient être évités grâce à une gestion efficace des populations de rongeurs ravageurs des cultures et des stocks. Par conséquent, la gestion des populations de rongeurs, qui sont des réservoirs d'agents pathogènes ou des ravageurs des stocks et des cultures, est un enjeu tant pour la sécurité alimentaire que pour la santé publique. En termes de politiques publiques, de nombreux pays africains ont mis en place des programmes d'intensification agricole visant à améliorer l'autosuffisance alimentaire, avec des risques directs de prolifération des rongeurs. Dans cet article, nous présentons le contexte du contrôle des rongeurs en Afrique dans les milieux ruraux et urbains, puis un aperçu de la réglementation et des utilisations des rodenticides, et nous documentons les situations problématiques qui en résultent à l'aide d'études de cas illustratifs. L'utilisation de rodenticides chimiques de synthèse est la méthode de gestion des rongeurs la plus couramment pratiquée, qui est non seulement toxique pour les humains, les autres animaux et l'environnement, mais aussi peu efficace contre les populations de rongeurs (par exemple, coûteuse en ressources, évolution de résistances, évitement des appâts). La circulation et l'utilisation incontrôlées de ces rodenticides dans de nombreux pays africains sont associées à des risques considérables pour la santé et l'environnement sans aucune amélioration significative en termes de contrôle des rongeurs ou d'atténuation de leurs nuisances