Desvars A.,CIRAD - Agricultural Research for Development |
Desvars A.,Center Regional Of Recherche Et Of Veille Sur Les Maladies Emergentes Of Locean Indien |
Desvars A.,Center Hospitalier Regional |
Naze F.,Center Hospitalier Regional |
And 4 more authors.
Epidemiology and Infection | Year: 2013
Leptospirosis is the major infectious disease on Reunion Island but little is known about the animal reservoir. We conducted a wide-ranging survey that included samples from 574 animals belonging to 12 species. The seroprevalence and prevalence of renal carriage varied greatly depending on the species, with the highest seroprevalence (79·5%) found in Norway rats, and the lowest (13·2%) in tenrecs. The renal carriage rate ranged from 84·6% in mice to 0% in tenrecs. Our results suggest that rodents are the most important reservoirs of leptospirosis on Reunion Island. The epidemiological role that animals play in human infection is discussed. For the first time, we quantified the renal concentration of leptospires in ten naturally infected mammals. The history of Reunion Island colonization probably explains why the circulating Leptospira serogroups were similar to those found in Europe. Our study provides evidence that will help implement preventive measures against this zoonosis. Copyright © 2012 Cambridge University Press.
Electrophysiological and behavioral characterization of bioactive compounds of the Thymus vulgaris, Cymbopogon winterianus, Cuminum cyminum and Cinnamomum zeylanicum essential oils against Anopheles gambiae and prospects for their use as bednet treatments
Deletre E.,UR HortSys |
Chandre F.,French National Center for Scientific Research |
Williams L.,European Biological Control Laboratory |
Dumenil C.,UR HortSys |
And 2 more authors.
Parasites and Vectors | Year: 2015
Background: Laboratory and field studies showed that repellent, irritant and toxic actions of common public health insecticides reduce human-vector contact and thereby interrupt disease transmission. One of the more effective strategies to reduce disease risk involves the use of long-lasting treated bednets. However, development of insecticide resistance in mosquito populations makes it imperative to find alternatives to these insecticides. Our previous study identified four essential oils as alternatives to pyrethroids: Thymus vulgaris, Cymbopogon winterianus, Cuminum cyminum, Cinnamomum zeylanicum. The objectives of this study were to identify active compounds of these essential oils, to characterize their biological activity, and to examine their potential as a treatment for bednets. Methods: We evaluated the electrophysiological, behavioural (repellency, irritancy) and toxic effects of the major compounds of these oils against Anopheles gambiae strain 'Kisumu'. Results: Aldehydes elicited the strongest responses and monoterpenes the weakest responses in electroantennogram (EAG) trials. However, EAG responses did not correlate consistently with results of behavioral assays. In behavioral and toxicity studies, several of the single compounds did exhibit repellency, irritancy or toxicity in An. gambiae; however, the activity of essential oils did not always correlate with activity expected from the major components. On the contrary, the biological activity of essential oils appeared complex, suggesting interactions between individual compounds and the insect under study. Data also indicated that the three effects appeared independent, suggesting that repellency mechanism(s) may differ from mechanisms of irritancy and toxicity. Conclusions: Based on the bioassays reported here, some of the compounds merit consideration as alternative bednet treatments. © 2015 Deletre et al.
Vidogbena F.,Center Regional pour la Promotion Agricole |
Vidogbena F.,University Abomey Calavi |
Adegbidi A.,University Abomey Calavi |
Tossou R.,University Abomey Calavi |
And 7 more authors.
Environment, Development and Sustainability | Year: 2015
If agro-ecological systems are to realize their potential as sustainable alternatives to conventional agricultural systems, innovation diffusion needs to be enhanced. We conducted surveys among 214 small-scale vegetable farmers in Benin, a food-deficit country in West Africa, on how they perceived the different attributes of eco-friendly nets (EFNs). The nets act as physical barriers against insects in vegetable production and so reduce pesticide use. Understanding farmer perceptions about new technologies helps reveal farmers’ propensity to adopt them. Intensity of attitude was measured on a Likert scale, and an ordered probit model was used to determine which characteristics of nets were most influential. Eighteen percent of farmers thought that EFNs would benefit them, but almost half preferred not to adopt this technology at all. The main reason for rejecting the nets was the perceived high labor requirement, particularly on larger plots of land. This largely negative perception was strongest among farmers with large areas cultivated with vegetables, farmers who had little or no experience in a trial, and those living far from extension services. We recommend expanded trials that engage a higher proportion of farmers, strengthening of external support for those wanting to use the nets and further technological development to reduce labor costs, improved access to finance and increased education about the negative impacts of insecticides abuse. © 2015 Springer Science+Business Media Dordrecht