Effect of temperature and relative humidity on the development times and survival of Synopsyllus fonquerniei and Xenopsylla cheopis, the flea vectors of plague in Madagascar

Acknowledgements We would like to thank Dr Lila Rahalison and Jocelyn Ratovonjato for their advice and help during the experiment. We are grateful to the staff of the Plague Unit and the Medical Entomology Unit at the Institut Pasteur de Madagascar, particularly Dr Nohal Elissa. Without their expertise this study would not have been possible. Sincere thanks to Mr Tojo Ramihangihajason for his technical assistance. We are indebted to the Institut Pasteur de Madagascar for an internal grant which facilitated additional laboratory research. Two Wellcome Trust fellowships supported ST during this work (081705 and 095171).Peer reviewedPublisher PD

Étude du devenir de l’indigo carmin dans la rivière Ikopa, Antananarivo - Madagascar

Contenu dans les effluents des industries textiles, l’indigo carmin devient une source majeure de pollution pour la rivière Ikopa longeant la ville d’Antananarivo (Madagascar), la quantité déversée dans la rivière pouvant aller jusqu’à 5,8 kg/Jour. Notre investigation concerne l’analyse du devenir de ce colorant dans l’environnement. On a étudié les propriétés et la photodégradation de l’indigo carmin en solution par irradiation solaire et sous l’effet du rayonnement d’une lampe-UV de longueur d’onde λ=365nm. Par ailleurs, on a déterminé les propriétés du colorant vis-à-vis des sédiments. Pour la coloration, les mesures ont été effectuées à la bande d’absorption de 610nm. Le taux de dégradation du colorant est déterminé par la mesure du temps de demi-vie (t1/2). Les résultats de notre travail ont montré que la dégradation dépend de la concentration initiale en colorant et du pH laquelle obéit à une cinétique d’ordre zéro. Nous avons conclu que l’irradiation solaire influe sur la diminution de la concentration de l’indigo carmin dans l’Ikopa. Avec l’irradiation solaire, les vitesses de dégradation calculées sont de 3,28x10-5 μmol L-1s-1 (Co =2,16x10-2 mmol L-1) et 4,93x10-5 μmol L-1s-1 (Co =4,3x10-2 mmol L-1).Les temps de demi-vie correspondants sont respectivement 42,66 et 56,34 heures. On a pu noter que le mécanisme de dégradation est plus rapide avec la lampe UV (λ=365nm, k=4,32x10-3 μmol L-1s-1, t1/2=19,83 heures). Par irradiation prolongée, l’indigo carmin pourrait être dégradé en composés minéraux. Les bactéries ordinaires telles que les coliformes, Escherichia coli et streptocoques, souvent présentes dans les eaux de surface pourraient contribuer à la dégradation de l’indigo dans la nature. Les risques de contamination sont fonction de la toxicité, de la mobilité et de la durée de vie des produits intermédiaires de dégradation: l’acide isatin sulfonique, l’acide formique et l’acide anthranilique lesquels sont cités par plusieurs auteurs. L’indigo carmin n’est pas entièrement retenu par les sédiments, d’où un risque de contamination des nappes aquifères.Mots-clés : photodégradation, indigo carmin, industrie textile, rivière Ikopa, Antananariv

Molecular and serological evidence of flea-associated typhus group and spotted fever group rickettsial infections in Madagascar

This research was supported by the Wellcome Trust (RCDF and Senior Fellowship to ST, #081705 and #095171), the Institut Pasteur de Madagascar, and the Global Emerging Infections Surveillance and Response System, a Division of the Armed Forces Health Surveillance Center [847705.82000.25GB.A0074].Peer reviewedPublisher PD

A Non-Stationary Relationship between Global Climate Phenomena and Human Plague Incidence in Madagascar

Acknowledgments We thank the Plague and Immunology Unit at the Institut Pasteur de Madagascar for data collection and management and supporting the study. Funding The analysis of the study was supported by the Leverhulme Trust Research Leadership Award F/0025/AC: ‘‘Predicting the effects of climate change on infectious diseases of animals’’ (awarded to MB). Funding for KSK was provided by a University of Liverpool PhD studentship award and for MB by BBSRC award ISIS 1813, ‘‘Climate change and the future of plague in Madagascar.’’ The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

Plague Circulation and Population Genetics of the Reservoir Rattus rattus: The Influence of Topographic Relief on the Distribution of the Disease within the Madagascan Focus.

International audienceBACKGROUND: Landscape may affect the distribution of infectious diseases by influencing the population density and dispersal of hosts and vectors. Plague (Yersinia pestis infection) is a highly virulent, re-emerging disease, the ecology of which has been scarcely studied in Africa. Human seroprevalence data for the major plague focus of Madagascar suggest that plague spreads heterogeneously across the landscape as a function of the relief. Plague is primarily a disease of rodents. We therefore investigated the relationship between disease distribution and the population genetic structure of the black rat, Rattus rattus, the main reservoir of plague in Madagascar. METHODOLOGYPRINCIPAL FINDINGS: We conducted a comparative study of plague seroprevalence and genetic structure (15 microsatellite markers) in rat populations from four geographic areas differing in topology, each covering about 150-200 km(2) within the Madagascan plague focus. The seroprevalence levels in the rat populations mimicked those previously reported for humans. As expected, rat populations clearly displayed a more marked genetic structure with increasing relief. However, the relationship between seroprevalence data and genetic structure differs between areas, suggesting that plague distribution is not related everywhere to the effective dispersal of rats. CONCLUSIONSSIGNIFICANCE: Genetic diversity estimates suggested that plague epizootics had only a weak impact on rat population sizes. In the highlands of Madagascar, plague dissemination cannot be accounted for solely by the effective dispersal of the reservoir. Human social activities may also be involved in spreading the disease in rat and human populations

Contribution of [64Cu]-ATSM PET in molecular imaging of tumour hypoxia compared to classical [18F]-MISO — a selected review

During the carcinogenesis process, tumour cells often have a more rapid proliferation potential than cells that participate in blood capillary formation by neoangiogenesis. As a consequence of the poorly organized vasculature of various solid tumours, a limited oxygen delivery is observed. This hypoxic mechanism frequently occurs in solid cancers and can lead to therapeutic resistance. The present selected literature review is focused on the comparison of two positron emitting radiopharmaceuticals agents, which are currently leaders in tumour hypoxia imaging by PET. {18F}-fluoromisonidazole (= FMISO) is most commonly used as an investigational PET agent with an investigational new drug exemption from the FDA, while {64Cu}-diacetyl-bis(N4-methylthiosemicarbazone) (64Cu-ATSM) has been presented as an alternative radiopharmaceutical not yet readily available. The comparison of these two radiopharmaceutical agents is particularly focused on isotope properties, radiopharmaceutical labelling process, pharmacological mechanisms, dosimetry data in patients, and clinical results in terms of image contrast. PET imaging has demonstrated a good efficacy in tumour hypoxia imaging with both FMISO and Cu-ATSM, but FMISO has presented too slow an in vivo accumulation and a weak image contrast of the hypoxia area. Despite a less favourable dosimetry, 64Cu-ATSM appears superior in terms of imaging performance, calling for industrial and clinical development of this innovative radiopharmaceutical. Nuclear Med Rev 2011; 14, 2: 90–9

Reproductive ecology of the black rat (Rattus rattus) in Madagascar : the influence of density-dependent and -independent effects

Funding Information: We are grateful to the technical and research staff from the Institut Pasteur de Madagascar and Association Vahatra for fieldwork assistance during this study. K.S. was supported by the Biotechnology and Biological Sciences Research Council (BBSRC) under the EastBio DTP [grant number BB/M010996/1]. This work was also supported by the Wellcome Trust [095171/Z/10/Z]; the Medical Research Council [MR/T029862/1]; and by the National Institute for Health Research (NIHR) (using the UK's Official Development Assistance [ODA] Funding) and Wellcome [219532/Z/19/Z] under the NIHR‐Wellcome Partnership for Global Health Research. The views expressed are those of the authors and not necessarily those of Wellcome, the NIHR, or the Department of Health and Social Care. For the purpose of Open Access, the authors have applied a CC BY license to any author accepted manuscript version arising. Research Funding Biotechnology and Biological Sciences Research Council (BBSRC) under the East-Bio DTP. Grant Number: BB/M010996/1 Wellcome TrustBiotechnology. Grant Number: 095171/Z/10/Z the Medical Research Council. Grant Number: MR/T029862/1 the National Institute for Health Research (NIHR) UK’s Official Development Assistance [ODA] Wellcome. Grant Number: 219532/Z/19/ZPeer reviewedPublisher PD

Low cost, low tech SNP genotyping tools for resource-limited areas: Plague in Madagascar as a model

Genetic analysis of pathogenic organisms is a useful tool for linking human cases together and/or to potential environmental sources. The resulting data can also provide information on evolutionary patterns within a targeted species and phenotypic traits. However, the instruments often used to generate genotyping data, such as single nucleotide polymorphisms (SNPs), can be expensive and sometimes require advanced technologies to implement. This places many genotyping tools out of reach for laboratories that do not specialize in genetic studies and/or lack the requisite financial and technological resources. To address this issue, we developed a low cost and low tech genotyping system, termed agarose-MAMA, which combines traditional PCR and agarose gel electrophoresis to target phylogenetically informative SNPs

Rodent control to fight plague : field assessment of methods based on rat density reduction

Research funding: Directorate General for International Relations and Strategy. Grant Number: 2018‐SB‐024‐18SSEOC049‐PMG7‐SSA5‐IPMMADAGASCAR ACKNOWLEDGMENTS: We are especially grateful to the health authorities and the population in Miantso and Ankazobe for allowing us to do this work and being so helpful. We thank the staff of the Plague Unit, Institut Pasteur de Madagascar, for helping with the field and laboratory work, especially Alain Berthin Rakotoarisoa and Andrianiaina Parfait Rakotonindrainy. This work was supported by a Directorate General for International Relations and Strategy grant (2018‐SB‐024‐18SSEOC049‐PMG7‐SSA5‐IPMMADAGASCAR) covering the project “Développement de contre‐mesures médicales à la peste à Madagascar” with scientific support of IRBA (French Armed Forces Biomedical Research Institute), within the framework of French MoD's involvement in G7 Global partnership. The French Agency for International Technical Expertise (AFETI) ensures the proper financial execution of the project and contributes to the implementation of cooperation actions under the control of the Directorate General for International Relations and Strategy. This research was also funded in part by the Wellcome Trust [095171/Z/10/Z] and the Institut Pasteur de Madagascar. For the purpose of Open Access, the authors have applied a CC BY public copyright license to any Author Accepted Manuscript version arising from this submission. K.S. was supported by the Biotechnology and Biological Sciences Research Council (BBSRC) under the EastBio DTP (grant number BB/M010996/1).Peer reviewedPublisher PD