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In order to increase the area of sugarcane production, planting techniques should ensure uniform crop emergence and control of weeds at reasonable cost. Experiments using single- bud setts have been conducted in several countries (Brazil, India, Indonesia, and Egypt). In this poster, we present the advantages of planting germinated single-bud setts grown in pots into a cover crop with the aim of reducing soil tillage and herbicide usage in an agro- ecological approach to sugarcane production. Two trials were carried out to assess the effectiveness of germinated single-bud setts compared with traditional planting of three-bud setts. This included i) the quantity of planting material, yield and components thereof, and ii) the use of herbicide. In the first trial, the weights and number of tillers per plant were measured at 11 months after planting. In the second trial, germinated single-bud setts were planted into plant cover originating from a succession of a planted mixture of Crotaleria juncea and Mucuna, and Avena sativa. Tillering, stalk elongation and yields (plant and ratoon) were compared with those of traditionally planted cane in single rows. Time and herbicide inputs were quantified. In the first trial, both yields and number of nodes per stalk were similar for the germinated single-bud setts and the traditionally planted cane, but the number of stalks was significantly higher (8%) for the germinated single-bud setts. The average multiplication rate of the single- bud setts was 1:99 at 11 months. In the second trial, the number of tillers was again 8 % higher for the single-bud setts. There was no significant differences in stalk elongation and yields. In ratoon cane, no significant differences were observed. From an economic point of view, a saving of more than 80% of buds was achieved at planting. However, the increased labor requirement generated additional costs. Planting germinated single-bud setts into mulch resulted in reduced herbicide applications and erosion risks. Our study highlighted planting of germinated single-bud setts (in pots) into mulch as a reliable and affordable technique. In terms of the planting operation and yields, it is comparable with conventional planting techniques and can reduce soil tillage and the use of herbicides. Theoretically this technique reduces the risk of erosion while favoring water retention and increased functional biodiversity. It gives the advantage of complete and homogeneous emergence, as well as the possibility of bringing complementary nutrients in the pot near to the roots. Nevertheless, for Reunion Island conditions, progress still needs to be made in terms of acclimatization and mechanical transplantation of young plants.

We investigated chloroquine sensitivity to Plasmodium falciparum in travelers returning to France and Canada from Haiti during a 23-year period. Two of 19 isolates obtained after the 2010 earthquake showed mixed pfcrt 76K+T genotype and high 50% inhibitory concentration. Physicians treating malaria acquired in Haiti should be aware of possible chloroquine resistance.

International audience; To answer the climate change challenge, all states have to reduce their greenhouse gas emissions, but also to adopt adaptation measures to limit the negative impacts of global warming on the population, the economy and the environment. The question arises especially for cities.Because of complex interactions between climate change, the evolution of cities and its inhabitants, studying adaptation strategies for cities requires a strong interdisciplinary approach: urban planners, architects, meteorologists, building engineers, economists, social sciences.Our four-step methodology consists firstly of defining interdisciplinary scenarios at several scales influencing the city evolution; secondly of simulating long term city evolution based on socio-economic and land-use models; thirdly of calculating impacts with physical models, and finally of calculating the indicators quantifying the adaptation strategies.Interdisciplinary systemic modelling performs well to evaluate several adaptation strategies for a very broad range of topics. Some of the results obtained for the agglomeration of Paris through our interdisciplinary research projects VURCA and MUSCADE will be discussed:A finding is that Urban planning strategies may have unexpected influence on city expansion when considered on the very long term of the climate change. Another is that the combine effect of global warming and UHI can lead in the future to larger energy consumption in summer than in winter.Indeed, air-conditioning will probably be necessary in 2100, because of expected stronger, and longer, heat waves. Limiting the UHI intensity allows for energy savings, and hence contributes to climate change mitigation. Adaptation strategies exist to limit air-conditioning use, both in time and intensity.Analysis of several vegetation strategies, at several spatial and planning scales (from agricultural practices in the city surroundings to urban trees and green-roofs) have been performed and evaluated. Architectural choices also allow to reduce the UHI. Finally, inhabitants' use and practices seem to be an efficient lever to reduce energy consumption in buildings and its impact on the urban climate.

IntroductionThere are growing concerns about the emergence of resistance to artemisinin-based combination therapies (ACTs). Since the widespread adoption of ACTs, there has been a decrease in the systematic surveillance of antimalarial drug resistance in many malaria-endemic countries. The aim of this work was to test whether data on travellers returning from Africa with malaria could serve as an additional surveillance system of local information sources for the emergence of drug resistance in endemic-countries.MethodologyData were collected from travellers with symptomatic Plasmodium falciparum malaria returning from Senegal (n = 1,993), Mali (n = 2,372), Cote d'Ivoire (n = 4,778) or Cameroon (n = 3,272) and recorded in the French Malaria Reference Centre during the period 1996-2011. Temporal trends of the proportion of parasite isolates that carried the mutant genotype, pfcrt 76T, a marker of resistance to chloroquine (CQ) and pfdhfr 108N, a marker of resistance to pyrimethamine, were compared for travellers and within-country surveys that were identified through a literature review in PubMed. The in vitro response to CQ was also compared between these two groups for parasites from Senegal.ResultsThe trends in the proportion of parasites that carried pfcrt 76T, and pfdhfr 108N, were compared for parasites from travellers and patients within-country using the slopes of the curves over time; no significant differences in the trends were found for any of the 4 countries. These results were supported by in vitro analysis of parasites from the field in Senegal and travellers returning to France, where the trends were also not significantly different.ConclusionThe results have not shown different trends in resistance between parasites derived from travellers or from parasites within-country. This work highlights the value of an international database of drug responses in travellers as an additional tool to assess the emergence of drug resistance in endemic areas where information is limited.

Background Chloroquine (CQ) was the main malaria therapy worldwide from the 1940s until the 1990s. Following the emergence of CQ-resistant Plasmodium falciparum, most African countries discontinued the use of CQ, and now promote artemisinin-based combination therapy as the first-line treatment. This change was generally initiated during the last decade in West and Central Africa. The aim of this study is to describe the changes in CQ susceptibility in this African region, using travellers returning from this region as a sentinel system. Methods The study was conducted by the Malaria National Reference Centre, France. The database collated the pfcrtK76T molecular marker for CQ susceptibility and the in vitro response to CQ of parasites from travellers’ isolates returning from Senegal, Mali, Ivory Coast or Cameroon. As a proxy of drug pressure, data regarding CQ intake in febrile children were collated for the study period. Logistic regression models were used to detect trends in the proportions of CQ resistant isolates. Results A total of 2874 parasite isolates were genotyped between 2000–2011. The prevalence of the pfcrt76T mutant genotype significantly decreased for Senegal (from 78% to 47%), Ivory Coast (from 63% to 37%), Cameroon (from 90% to 59%) and remained stable for Mali. The geometric mean of the 50% inhibitory concentration (IC50) of CQ in vitro susceptibility and the proportion of resistant isolates (defining resistance as an IC50 value > 100 nM) significantly decreased for Senegal (from 86 nM (59%) to 39 nM (25%)), Mali (from 84 nM (50%) to 51 nM (31%)), Ivory Coast (from 75 nM (59%) to 29 nM (16%)) and Cameroon (from 181 nM (75%) to 51 nM (37%)). Both analyses (molecular and in vitro susceptibility) were performed for the 2004–2011 period, after the four countries had officially discontinued CQ and showed an accelerated decline of the resistant isolates for the four countries. Meanwhile, CQ use among children significantly deceased in this region (fixed effects slope = −0.3, p -3). Conclusions An increase in CQ susceptibility following official withdrawal of the drug was observed in travellers returning from West and Central African countries. The same trends were observed for molecular and in vitro analysis between 2004-2011and they correlated to the decrease of the drug pressure.

Plasmodium falciparum malaria is a serious health hazard for travelers to malaria-endemic areas and is often diagnosed on return to the country of residence. We conducted a retrospective study of imported falciparum malaria among travelers returning to France from malaria-endemic areas from 1996 through 2003. Epidemiologic, clinical, and parasitologic data were collected by a network of 120 laboratories. Factors associated with fatal malaria were identified by logistic regression analysis. During the study period, 21,888 falciparum malaria cases were reported. There were 96 deaths, for a case-fatality rate of 4.4 per 1,000 cases of falciparum malaria. In multivariate analysis, risk factors independently associated with death from imported malaria were older age, European origin, travel to East Africa, and absence of chemoprophylaxis. Fatal imported malaria remains rare and preventable. Pretravel advice and malaria management should take into account these risk factors, particularly for senior travelers

Between 1987 and 1989 the trend in the chloroquine resistance of Plasmodium falciparum in the mining town of Mounana in south-eastern Gabon was studied in vivo and in vitro in 58 and 158 subjects, respectively, aged from 1 to 15 years. The tests used were a simplified variant of the standard WHO 7-day test for the in vivo study and the isotopic semi-microtest of chemosensitivity for the in vitro study. The health situation in 1989 showed no change from the 1987 situation, but an increase in febrile symptoms suggestive of malaria was observed in 1989. This observation may be linked to a decrease in the distribution of chloroquine since 1987, accompanied by the use of other antimalarials following the appearance of chloroquine-resistant strains. While the parasitological efficacy in vivo remained the same in 1989, there was a decrease in the proportion of strains resistant to chloroquine in vitro compared to 1987; likewise, the therapeutic efficacy as estimated from temperature readings was better in 1989 than in 1987: the modification of the prophylactic strategy since 1986 and the drop in chloroquine consumption since 1987 could be responsible for a stabilization of chloroquine resistance at Mounana. The authors consider it appropriate in this region to continue treating malaria in children with chloroquine (in a dosage of 25 mg/kg) and to use a second-line treatment in the event of the recurrence of malaria symptoms within the next two weeks.