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International audience; In recent decades, the invasive Aedes albopictus vector has spread across Europe and is responsible for numerous outbreaks of autochthonous arboviral disease. The aim of this study was to identify epidemiological and sociological risk factors related to individual levels of exposure to Aedes albopictus bites. A multidisciplinary survey was conducted with volunteer blood donors living in areas either colonised or not by Aedes albopictus in mainland France. Individual levels of exposure were evaluated by measuring the IgG level specific to Aedes albopictus saliva. The most striking risk factors concerned the localisation and characteristics of the dwelling. Individuals living in areas colonised prior to 2009 or recently colo-nised (between 2010 and 2012) had higher anti-salivary gland extract IgG levels compared with those who were living in areas not yet colonised by Ae. albopictus. The type of dwelling did not seem to impact the level of exposure to Aedes bites. People living in apartments had a higher anti-salivary gland extract IgG level than those living in individual houses but the difference was not statistically significant. Interestingly, the presence of air conditioning or window nets was associated with a noticeable reduction in bite intensity.

Over the past decade, a significant increase in the circulation of infectious agents was observed. With the spread and emergence of epizootics, zoonoses and epidemics, the risks of pandemics became more and more critical. Human and animal health has also been threatened by antimicrobial resistance, environmental pollution and the development of multifactorial and chronic diseases. This highlighted the increasing globalization of health risks and the importance of the human-animal-ecosystem interface in the evolution and emergence of pathogens. A better knowledge of causes and consequences of certain human activities, lifestyles and behaviors in ecosystems is crucial for a rigorous interpretation of disease dynamics and to drive public policies. As a global good, health security must be understood on a global scale and from a global and cross-cutting perspective, integrating human health, animal health, plant health, ecosystems health and biodiversity. In this paper, we discuss how crucial it is to consider ecological, evolutionary and environmental sciences in understanding the emergence and re-emergence of infectious diseases and in facing the challenges of antimicrobial resistance. We also discuss the application of the “One Health” concept to non-communicable chronic diseases linked to exposure to multiple stresses, including toxic stress, and new lifestyles. Finally, we draw up a list of barriers that need removing and the ambitions that we must nurture for the effective application of the “One Health” concept. We conclude that the success of this One Health concept now requires breaking down the interdisciplinary barriers that still separate human and veterinary medicine from ecological, evolutionary and environmental sciences. The development of integrative approaches should be promoted by linking the study of factors underlying stress responses to their consequences on ecosystem functioning and evolution. This knowledge is required for the development of novel control strategies inspired by environmental mechanisms leading to desired equilibrium and dynamics in healthy ecosystems and must provide in the near future a framework for more integrated operational initiatives.

Only pyrethroid insecticides have so far been recommended for the treatment of mosquito nets for malaria control. Increasing resistance of malaria vectors to pyrethroids threatens to reduce the potency of this important method of vector control. Among the strategies proposed for resistance management is to use a pyrethroid and a non-pyrethroid insecticide in combination on the same mosquito net, either separately or as a mixture. Mixtures are particularly promising if there is potentiation between the two insecticides as this would make it possible to lower the dosage of each, as has been demonstrated under laboratory conditions for a mixture of bifenthrin (pyrethroid) and carbosulfan (carbamate). The effect of these types of treatment were compared in experimental huts on wild populations of Anopheles gambiae Giles and the nuisance mosquito Culex quinquefasciatus Say, both of which are multi-resistant. Four treatments were evaluated in experimental huts over six months: the recommended dosage of 50 mg m−2 bifenthrin, 300 mg m−2 carbosulfan, a mosaic of 300 mg m−2 carbosulfan on the ceiling and 50 mg m−2 bifenthrin on the sides, and a mixture of 6.25 mg m−2 carbosulfan and 25 mg m−2 bifenthrin. The mixture and mosaic treatments did not differ significantly in effectiveness from carbosulfan and bifenthrin alone against anophelines in terms of deterrency, induced exophily, blood feeding inhibition and overall mortality, but were more effective than in earlier tests with deltamethrin. These results are considered encouraging, as the combination of different classes of insecticides might be a potential tool for resistance management. The mixture might have an advantage in terms of lower cost and toxicity

International audience; The chemical compositions of Corsican and Sardinian Eryngium maritimum L. essential oils were investigated using column chromatography, gas chromatography with flame ionization detection and gas chromatography-mass spectrometry in electron impact mode. Sixty-three compounds were identified accounting for 85.8-95.7% of the total amount. With germacrene D (13.7-45.9%), three uncommon oxygenated sesquiterpenes, 4H-cadin-9-en-15-al (18.4-27.6%), 4H-cadin-9-en-15-ol (2.2-14.3%) and 4H-muurol-9-en-15-al (4.3-9.3%), were identified as main components of the essential oils obtained from the plant aerial parts. Relative to these, essential oils from the roots differed drastically with high contents of 2,4,5-trimethylbenzaldehyde (39.8%), 2,3,6-trimethylbenzaldehyde (29.0%) and a-muurolene (23.5%). The chemical variability of Corsican and Sardinian E. maritimum essential oils was studied using statistical analysis. A direct correlation between the island of origin of the sample essential oils and their chemical compositions was assessed. Corsican essential oils exhibited higher amounts of hydrocarbon terpenes than Sardinian samples. Relative to other Eryngium species, Corsican and Sardinian E. aritimumessential oils exhibited original compositions with sesquiterpene aldehydes. These compounds, together with total essential oil, were tested for antioxidant properties using the DPPH and ABTS radical-scavenging activity tests. No eaningful activity could be attributed to sesquiterpene aldehydes and the corresponding alcohols but the total essential oil and the oxygenated fraction of E. maritimumboth demonstrated strong antioxidant properties.

International audience; The chemical compositions of the aerial parts essential oils of Chamaemelum mixtum (L.) Alloni from Corsica and Sardinia were investigated employing gas chromatography and gas chromatography/mass spectrometry. The structure of (Z)-heptadeca- 9,16-dien-7-one, a natural compound not previously described, was elucidated by gas chromatography/mass spectrometry (electron impact and chemical ionization) and one dimensional and two-dimensional nuclear magnetic resonance spectroscopy. The variation in Chamaemelum mixtum essential oil was studied and statistical analysis showed the clustering of oil samples into three groups according to the amount of oxygenated compounds; these groups correlated to the harvest area. The strong biological activity of the oxygenated fraction (minimum inhibitory concentration of less than 0.1 mg/mL) of the Corsican oil against Candida albicans, Citrobacter frendii, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes and Staphillococcus aureus can be attributed to the presence of irregular monoterpene alcohols and (Z)-heptadeca-9,16-dien-7-one.

International audience; Investigation of the essential oil of the aerial parts of Eryngium maritimum L. from Corsica led to the isolation of one known sesquiterpene (1) and three new oxygenated sesquiterpenes with a muurolane or cadinane skeleton (2-4). Structure assignments of 4βH-muurol-9-en-15-al (1), 4βH-cadin-9-en-15-al (2), 4βH-muurol-9-en-15-ol (3) and 4βH-cadin-9-en-15-ol (4) were carried out by GC/MS (EI and CI) and comprehensive 1D and 2D NMR spectroscopy. Antibacterial activity of Eryngium maritimum L. oil and column chromatography fractions have been investigated for the first time. The oxygenated fraction, which contains the four sesquiterpenes, was efficient against Listeria monocytogenes and Echerichia coli.

International audience; Analysis of chemical compositions of 18 oil samples of Anthemis maritima L. essential oils from Corsica and Sardinia were investigated by GC, GC-MS and NMR. Integrated analysis allowed the identification of 124 components which accounted for 83.3 % to 91.6 % of the total amount. Principal components analysis established the occurrence of two clusters. The former cluster enclosed oil samples dominated by trans-chrysanthenyl acetate (34.9 - 68.5 %) while the latter cluster enclosed oil samples which exhibited 6-methyl-5-hepten-2-one (5.7 - 24.9 %) and cis-chrysanthenyl 2-methylbutyrate (3.2 - 15.4 %) as main components. The essential oils were dominated by oxygenated monoterpenes (16.4 - 81.8 %). Among them, 16 chrysanthenyl esters (10.8 - 74.5 %) were identified, 12 were laboratory-prepared and for the first time their 13C-NMR data and the 1H-NMR data of 7 of them were reported.

International audience; Pyrethroid resistance was investigated in thirty-three samples of Culex quinquefasciatus Say from twenty-five cities in Cote d'Ivoire and Burkina Faso. Permethrin resistance ratios at LC50 ranged from 9.5- to 82-fold in Cote d'Ivoire and from 17- to 49-fold in Burkina Faso. For deltamethrin, resistance ratios were lower and ranged from nine to thirty-eight in both countries. A strain was selected with permethrin to investigate resistance mechanisms. After forty-two generations of selection, permethrin resistance level reached 3750-fold, but deltamethrin resistance remained unexpectedly unchanged. This indicated that a specific mechanism was involved in permethrin resistance. Synergist assays and biochemical tests indicated that resistance was partly due to P450-dependent oxidases. A target site insensitivity (kdr) was also involved, associated with DDT cross resistance and a dramatic loss of permethrin knockdown effect on adults. This resistance should be taken into consideration when planning the use of pyrethroid-impregnated materials in urban areas, as Culex is by far the main source of nuisance. Any failure in nuisance control due to resistance is likely to demotivate people in using impregnated materials.

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In the field, the kdr mutation, involved in pyrethroid resistance, has been found widely distributed in the Savanna form of Anopheles gambiae s.s., but never in wild populations of the Mopti form or An. arabiensis, even in areas where both occur in sympatry with resistant Savanna populations. Under laboratory conditions, Mopti and Savanna forms were fully able to interbreed and the kdr mutation was transmissible from one form to the other. Both forms appeared to be exposed to pyrethroid selection pressure in the field. The absence of the kdr mutation in the Mopti form and the total lack of Mopti-Savanna heterozygotes in field populations provides further evidence of a pre-copulatory barrier to gene flow between these two forms. Molecular markers, including kdr, are powerful tools for studying population genetics and circulation of resistance genes, and should be used through an integrated approach for a better understanding of the speciation process.

Field samples of #Anopheles gambiae$ s.s. from Côte d'Ivoire were tested with 5 pyrethroids (cyfluthrin, lambda-cyhalothrin, alpha-cypermethrin, deltamethrin, permethrin), 1 pseudo-pyrethroid (etofenprox), and an organochlorine (DDT). With the use of World Health Organization diagnostic tests, 5 out of 6 samples were found cross-resistant to these insecticides. A strong decrease in knockdown effect and mortality was also observed when testing deltamethrin-impregnated nettings. With a polymerase chain reaction amplification of specfic alleles diagnostic test, resistance was found associated with the presence of a kdr mutation. The strong correlation between kdr allelic frequency and resistance to DDT or etofenprox indicated that kdr was the main resistance factor for these 2 insecticides. On the contrary, a lower correlation was observed between kdr frequency and resistance to 4 of the 5 pyrethroids tested, suggesting that another mechanism was also involved, likely a metabolic detoxification. These results point out the necessity to monitor pyrethroid resistance and the presence of kdr before implementation of any impregnated bed-net programs for malaria control. (Résumé d'auteur)

International audience; Essential oil of aerial parts of Eryngium maritimum L. (EM oil) was obtained by hydrodistillation and analyzed by GC and GC/MS. After column chromatography (CC), 58 compounds accounting for 97.1 % of the oil were identified. The essential oil was dominated by oxygenated sesquiterpenes (57.9 %). The main components were 4βH-cadin-9-en-15-al (36.5 %), germacrene D (31.6 %), 4βH-cadin-9-en-15-ol (8.3 %) and 4βH-muurol-9-en-15-al (6.5 %). The inhibition of the corrosion of mild steel in 1M HCl solution by EM oil and its CC-fractions have been studied using weight loss measurements. Inhibition was found to increase with increasing concentration of the essential oil to attain 97.91 % at 2 mg/mL. The effect of temperature on the corrosion behavior of mild steel in 1M HCl without and with the EM oil at 2 mg/mL was also studied. The inhibition was assumed to occur via adsorption of the inhibitor molecules on the mild steel surface according to the Langmuir adsorption isotherm. The thermodynamic parameters for activation and adsorption processes were calculated and discussed. The results obtained showed that the EM oil could serve as an environmentally friendly inhibitor of the corrosion of mild steel in HCl media

The efficacy of permethrin-treated Olyset Net mosquito nets on malaria transmission and morbidity was studied in Kafine, a village located in the savanna region of the Cote d'Ivoire in Africa. After collecting sociodemographic, entomological, and parasitological data, bednets were distributed first in the southern half of the village and then in the whole village. Throughout the study period, mosquito specimens were captured on the skin of inhabitants at four points in the village between 6 PM and 6 AM both inside (but outside bednets) and outside houses. Prior to distribution of bednets, the mean biting rate (MBR) by Anopheles gambiae was 77.4 bites per man per night (b/m/n). The mean parturity rate (MPR) was 40.6 p. 100, the sporozootic index (SI) was 0.99 p. 100, and the mean entomological inoculation rate (MEIR) was 0.7 infectious bites per man per night (b+/m/n). Six months after distribution of bednets in the southern half of the village, MBR was 80.2 b/m/n, MPR was 32 p. 100, SI was 1.8 p. 100, and MEIR was 0.83 b+/m/n. After extending distribution to the whole village, data from November 1996 to July 1997 were as follows: MBR, 67.8 b/m/n; MPR, 20.1 p. 100; SI, 0.65 p. 100; and MEIR, 0.66 p. 100. From August 1977 to July 1998, data were as follows: MBR, 102.6 b/m/n; MPR, 26.2 p. 100; SI, 1.15 p. 100; and MEIR, 0.74 b+/m/n. Comparative analysis of these data showed that use of bednets had no effect on the bite or entomological inoculation rate. This is in agreement with the documented resistance of vectors in the study zone to permethrin. Despite the known stimulation/repulsion effect of permethrin, use of treated bednets had no real impact on transmission. This inefficacy could be related to the high prevalence (80 p. 100) of the Kdr gene (responsible for resistance) in the savanna form of Anopheles gambiae.

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