37 results on '"Héraud, Jean-Michel"'
Search Results
2. Cross-sectional cycle threshold values reflect epidemic dynamics of COVID-19 in Madagascar
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Andriamandimby, Soa Fy, Brook, Cara E., Razanajatovo, Norosoa, Randriambolamanantsoa, Tsiry H., Rakotondramanga, Jean-Marius, Rasambainarivo, Fidisoa, Raharimanga, Vaomalala, Razanajatovo, Iony Manitra, Mangahasimbola, Reziky, Razafindratsimandresy, Richter, Randrianarisoa, Santatra, Bernardson, Barivola, Rabarison, Joelinotahiana Hasina, Randrianarisoa, Mirella, Nasolo, Frédéric Stanley, Rabetombosoa, Roger Mario, Ratsimbazafy, Anne-Marie, Raharinosy, Vololoniaina, Rabemananjara, Aina H., Ranaivoson, Christian H., Razafimanjato, Helisoa, Randremanana, Rindra, Héraud, Jean-Michel, and Dussart, Philippe
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- 2022
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3. Monitoring for outbreak-associated excess mortality in an African city: Detection limits in Antananarivo, Madagascar
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Rasambainarivo, Fidisoa, Rasoanomenjanahary, Anjarasoa, Rabarison, Joelinotahiana Hasina, Ramiadantsoa, Tanjona, Ratovoson, Rila, Randremanana, Rindra, Randrianarisoa, Santatriniaina, Rajeev, Malavika, Masquelier, Bruno, Heraud, Jean Michel, Metcalf, C. Jessica E., and Rice, Benjamin L.
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- 2021
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4. Assessment of poliovirus antibody seroprevalence in high risk areas for vaccine derived poliovirus transmission in Madagascar
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Razafindratsimandresy, Richter, Mach, Ondrej, Heraud, Jean-Michel, Bernardson, Barivola, Weldon, William C., Oberste, M. Steven, and Sutter, Roland W.
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- 2018
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5. Drivers of Rift Valley fever epidemics in Madagascar
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Lancelot, Renaud, Béral, Marina, Rakotoharinome, Vincent Michel, Andriamandimby, Soa-Fy, Héraud, Jean-Michel, Coste, Caroline, Apolloni, Andrea, Squarzoni-Diaw, Cécile, de La Rocque, Stéphane, Formenty, Pierre B. H., Bouyer, Jérémy, Wint, G. R. William, and Cardinale, Eric
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- 2017
6. Babesial infection in the Madagascan flying fox, Pteropus rufus É. Geoffroy, 1803
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Ranaivoson, Hafaliana C., Héraud, Jean-Michel, Goethert, Heidi K., Telford, III, Sam R., Rabetafika, Lydia, and Brook, Cara E.
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- 2019
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7. Smallpox Vaccine Safety Is Dependent on T Cells and Not B Cells
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Gordon, Shari N., Cecchinato, Valentina, Andresen, Vibeke, Heraud, Jean-Michel, Hryniewicz, Anna, Parks, Robyn Washington, Venzon, David, Chung, Hye-kyung, Karpova, Tatiana, McNally, James, Silvera, Peter, Reimann, Keith A., Matsui, Hajime, Kanehara, Tomomi, Shinmura, Yasuhiko, Yokote, Hiroyuki, and Franchini, Genoveffa
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- 2011
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8. Suburban Transmission of Q Fever in French Guiana: Evidence of a Wild Reservoir
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Gardon, Jacques, Héraud, Jean-Michel, Laventure, Stéphane, Ladam, Aélis, Capot, Philippe, Fouquet, Eric, Favre, Jacques, Weber, Sacha, Hommel, Didier, Hulin, Alain, Couratte, Yves, and Talarmin, Antoine
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- 2001
9. How geographic access to care shapes disease burden: The current impact of post-exposure prophylaxis and potential for expanded access to prevent human rabies deaths in Madagascar
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Rajeev, Malavika, Guis, Hélène, Edosoa, Glenn, Hanitriniaina, Chantal, Randrianarijaona, Anjasoa, Mangahasimbola, Reziky Tiandraza, Hierink, Fleur, Ramiandrasoa, Ravo, Nely, José, Héraud, Jean Michel, Andriamandimby, Soa Fy, Baril, Laurence, Metcalf, C. Jessica, Hampson, Katie, Rajeev, Malavika, Guis, Hélène, Edosoa, Glenn, Hanitriniaina, Chantal, Randrianarijaona, Anjasoa, Mangahasimbola, Reziky Tiandraza, Hierink, Fleur, Ramiandrasoa, Ravo, Nely, José, Héraud, Jean Michel, Andriamandimby, Soa Fy, Baril, Laurence, Metcalf, C. Jessica, and Hampson, Katie
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Background: Post-exposure prophylaxis (PEP) is highly effective at preventing human rabies deaths, however access to PEP is limited in many rabies endemic countries. The 2018 decision by Gavi to add human rabies vaccine to its investment portfolio should expand PEP availability and reduce rabies deaths. We explore how geographic access to PEP impacts the rabies burden in Madagascar and the potential benefits of improved provisioning. Methodology & principal findings: We use spatially resolved data on numbers of bite patients seeking PEP across Madagascar and estimates of travel times to the closest clinic providing PEP (N = 31) in a Bayesian regression framework to estimate how geographic access predicts reported bite incidence. We find that travel times strongly predict reported bite incidence across the country. Using resulting estimates in an adapted decision tree, we extrapolate rabies deaths and reporting and find that geographic access to PEP shapes burden sub-nationally. We estimate 960 human rabies deaths annually (95% Prediction Intervals (PI): 790–1120), with PEP averting an additional 800 deaths (95% PI: 640–970) each year. Under these assumptions, we find that expanding PEP to one clinic per district (83 additional clinics) could reduce deaths by 19%, but even with all major primary clinics provisioning PEP (1733 additional clinics), we still expect substantial rabies mortality. Our quantitative estimates are most sensitive to assumptions of underlying rabies exposure incidence, but qualitative patterns of the impacts of travel times and expanded PEP access are robust. Conclusions & significance: PEP is effective at preventing rabies deaths, and in the absence of strong surveillance, targeting underserved populations may be the most equitable way to provision PEP. Given the potential for countries to use Gavi funding to expand access to PEP in the coming years, this framework could be used as a first step to guide expansion and improve targeting of inter
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- 2021
10. External quality assessment of Rift Valley fever diagnosis in countries at risk of the disease: African, Indian Ocean and Middle-East regions
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Pédarrieu, Aurélie, El Mellouli, Fatiha, Khallouki, Hanane, Zro, Khalil, Sebbar, Ghizlane, Sghaier, Soufien, Madani, Hafsa, Bouayed, Nadera, Lo, Modou Moustapha, Diop, Mariame, Ould El Mamy, Ahmed Bezeid, Barry, Yahya, Dakouo, Marthin, Traoré, Abdallah, Gagara, Haladou, Souley, Maman Moutari, Achá, Sara, Mapaco, Lourenço, Chang'a, Jelly, Nyakilinga, Denis, Lubisi, Baratang A., Tshabalala, Thabisile, Filippone, Claudia, Héraud, Jean Michel, Chamassy, Sitti Bahyat, Achiraffi, Abdou, Keck, Nicolas, Grard, Gilda, Mohammed, Kareem Abdelfattah Abdelwahab, Alrizqi, Abdulwahed Mohammed, Cetre-Sossah, Catherine, Pédarrieu, Aurélie, El Mellouli, Fatiha, Khallouki, Hanane, Zro, Khalil, Sebbar, Ghizlane, Sghaier, Soufien, Madani, Hafsa, Bouayed, Nadera, Lo, Modou Moustapha, Diop, Mariame, Ould El Mamy, Ahmed Bezeid, Barry, Yahya, Dakouo, Marthin, Traoré, Abdallah, Gagara, Haladou, Souley, Maman Moutari, Achá, Sara, Mapaco, Lourenço, Chang'a, Jelly, Nyakilinga, Denis, Lubisi, Baratang A., Tshabalala, Thabisile, Filippone, Claudia, Héraud, Jean Michel, Chamassy, Sitti Bahyat, Achiraffi, Abdou, Keck, Nicolas, Grard, Gilda, Mohammed, Kareem Abdelfattah Abdelwahab, Alrizqi, Abdulwahed Mohammed, and Cetre-Sossah, Catherine
- Abstract
Middle East, North Africa, South Africa, and the Indian Ocean participated in the initiative. Two commercial kits and two in-house serological assays for the detection of RVFV specific IgG antibodies were tested. Sixteen of the 18 participating laboratories (88.9%) used com- mercial kits, the analytical performance of test sensitivity and specificity based on the sero- neutralisation test considered as the reference was 100%. The results obtained by the laboratories which used the in-house assay were correct in only one of the two criteria (either sensitivity or specificity). In conclusion, most of the laboratories performed well in detecting RVFV specific IgG antibodies and can therefore be considered to be prepared. Three laboratories in three countries need to improve their detection capacities. Our study demonstrates the importance of conducting regular proficiency tests to evaluate the level of preparedness of countries and of building a network of competent laboratories in terms of laboratory diagnosis to better face future emerging diseases in emergency conditions.
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- 2021
11. Enabling animal rabies diagnostic in low access areas: Sensitivity and specificity of a molecular diagnostic test from cerebral tissue dried on filter paper
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Rasolonjatovo, Felana Suzah, Guis, Hélène, Rajeev, Malavika, Dacheux, Laurent, Nomenjanahary, Lalaina Arivony, Razafitrimo, Girard, Rafisandrantantsoa, Jean-Théophile, Cetre-Sossah, Catherine, Héraud, Jean Michel, Andriamandimby, Soa Fy, Rasolonjatovo, Felana Suzah, Guis, Hélène, Rajeev, Malavika, Dacheux, Laurent, Nomenjanahary, Lalaina Arivony, Razafitrimo, Girard, Rafisandrantantsoa, Jean-Théophile, Cetre-Sossah, Catherine, Héraud, Jean Michel, and Andriamandimby, Soa Fy
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Rabies is a lethal zoonotic encephalomyelitis that causes an estimated 59,000 human deaths yearly worldwide. Although developing countries of Asia and Africa bear the heaviest burden, surveillance and disease detection in these countries is often hampered by the absence of local laboratories able to diagnose rabies and/or the difficulties of sample shipment from low-access areas to national reference laboratories. Filter papers offer a convenient cost-effective alternative for the sampling, shipment, and storage of biological materials for the diagnosis of many pathogens including rabies virus, yet the properties of diagnostic tests using this support have not been evaluated thoroughly. Sensitivity and specificity of molecular diagnosis of rabies infection using a reverse transcription followed by a hemi-nested polymerase chain reaction (RT-hn-PCR) either directly on brain tissue or using brain tissue dried on filter paper were assessed on 113 suspected field animal samples in comparison to the direct fluorescent antibody test (FAT) recommended by the World Health Organization as one of the reference tests for rabies diagnosis. Impact of the duration of the storage was also evaluated. The sensitivity and the specificity of RT-hn-PCR i) on brain tissue were 96.6% (95% CI: [88.1–99.6]) and 92.7% (95% CI: [82.4–98.0]) respectively and ii) on brain tissue dried on filter paper 100% (95% CI: [93.8–100.0]) and 90.9% (95% CI: [80.0–97.0]) respectively. No loss of sensitivity of RT-hn-PCR on samples of brain tissue dried on filter paper left 7 days at ambient temperature was detected indicating that this method would enable analyzing impregnated filter papers sent to the national reference laboratory at ambient temperature within a 1-week shipment time. It could therefore be an effective alternative to facilitate storage and shipment of samples from low-access areas to enhance and expand rabies surveillance.
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- 2020
12. Revealing Measles Outbreak Risk With a Nested Immunoglobulin G Serosurvey in Madagascar
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Winter, Amy K, Wesolowski, Amy P, Mensah, Keitly J, Ramamonjiharisoa, Miora Bruna, Randriamanantena, Andrianmasina Herivelo, Razafindratsimandresy, Richter, Cauchemez, Simon, Lessler, Justin, Ferrari, Matt J, Metcalf, C Jess E, Héraud, Jean-Michel, Johns Hopkins Bloomberg School of Public Health [Baltimore], Johns Hopkins University (JHU), Princeton University, Unité de Virologie [Antananarivo, Madagascar] (IPM), Institut Pasteur de Madagascar, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP), Modélisation mathématique des maladies infectieuses, Centre National de la Recherche Scientifique (CNRS)-Institut Pasteur [Paris], Pennsylvania State University (Penn State), Penn State System, This work was funded by the Bill and Melinda Gates Foundation (grant OPP1094793) and the Wellcome Trust (grant 106866/Z/15/Z)., We thank the staff of the Direction of the Expanded Program on Immunization from the Malagasy Ministry of Public Health, for their dedicated work toward measles immunization, and all staff of the health sector involved in measles surveillance. We also thank all the staff from the World Health Organization national reference lab at Institut Pasteur de Madagascar for their work regarding testing and database sharing., Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), and Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS)
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Adult ,Male ,surveillance Abbreviations: IgG ,Adolescent ,Original Contributions ,Measles Vaccine ,Enzyme-Linked Immunosorbent Assay ,World Health Organization ,Antibodies, Viral ,Disease Outbreaks ,WHO ,Young Adult ,Age Distribution ,Seroepidemiologic Studies ,Madagascar ,measles ,Humans ,Child ,Rubella ,Models, Statistical ,supplementary immunization activities ,SIA ,Infant ,Middle Aged ,serological survey ,Child, Preschool ,Immunoglobulin G ,surveillance ,[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie ,Female - Abstract
International audience; Madagascar reports few measles cases annually and high vaccination campaign coverage. However, the underlying age profile of immunity and risk of a measles outbreak is unknown. We conducted a nested serological survey, testing 1,005 serum samples (collected between November 2013 and December 2015 via Madagascar's febrile rash surveillance system) for measles immunoglobulin G antibody titers. We directly estimated the age profile of immunity and compared these estimates with indirect estimates based on a birth cohort model of vaccination coverage and natural infection. Combining these estimates of the age profile of immunity in the population with an age-structured model of transmission, we further predicted the risk of a measles outbreak and the impact of mitigation strategies designed around supplementary immunization activities. The direct and indirect estimates of age-specific seroprevalence show that current measles susceptibility is over 10%, and modeling suggests that Madagascar may be at risk of a major measles epidemic.
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- 2018
13. Reduced cell turnover in lymphocytic monkeys infected by human T-lymphotropic virus type 1
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Debacq, Christophe, Héraud, Jean-Michel, Asquith, Becca, Bangham, Charles, Merien, Fabrice, Moules, Vincent, Mortreux, Franck, Wattel, Eric, Burny, Arsène, Kettmann, Richard, Kazanji, Mirdad, and Willems, Luc
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- 2005
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14. Development and validation of a pen side test for Rift Valley fever
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Pedarrieu, Aurelie, Juremalm, Mikael, Van Vuren, Petrus Jansen, Brun, Alejandro, EL Mamy, Ahmed Bezeid Ould, Héraud, Jean-Michel, Filippone, Claudia, Ravalohery, Jean-Pierre, Chaabihi, Hassan, Albina, Emmanuel, Dommergues, Laure, Paweska, Janusz, Cardinale, Eric, and Cêtre-Sossah, Catherine
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Santé publique et épidémiologie - Abstract
Background Rift Valley fever (RVF) is one of the main vector borne zoonotic diseases that affects a wide range of ruminants and human beings in Africa and the Arabian Peninsula. A rapid and specific test for RVF diagnosis at the site of a suspected outbreak is crucial for the implementation of control measures. Methodology/Principal findings A first-line lateral flow immunochromatographic strip test (LFT) was developed for the detection of the nucleoprotein (N) of the RVF virus (RVFV). Its diagnostic performance characteristics were evaluated using reference stocks isolates recovered from different hosts and in geographic regions mimicking clinical specimens and from known RVF negative serum samples. A high level of diagnostic accuracy (DSe (35/35), DSp (167/169)) was observed, including the absence of cross-reactivity with viruses belonging to different genera. Author summary Rift Valley fever (RVF) is a viral disease that affects a wide range of animals and human beings in Africa and the Arabian Peninsula involving low case fatality rates. A rapid and specific test for RVF diagnosis at the site of a suspected outbreak is crucial for the implementation of control measures. Here, we report the development and the evaluation of the diagnostic performance characteristics of a pen-side test found to be a highly accurate and valuable first-line diagnostic tool for on-site RVF detection.
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- 2019
15. Development and validation of a pen side test for Rift Valley fever
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Cetre-Sossah, Catherine, Pédarrieu, Aurélie, Juremalm, Mikael, Jansen Van Vuren, Petrus, Brun, Alejandro, Ould El Mamy, Ahmed Bezeid, Héraud, Jean Michel, Filippone, Claudia, Ravalohery, Jean-Pierre, Chaabihi, Hassan, Albina, Emmanuel, Dommergues, Laure, Paweska, Janusz, Cardinale, Eric, Cetre-Sossah, Catherine, Pédarrieu, Aurélie, Juremalm, Mikael, Jansen Van Vuren, Petrus, Brun, Alejandro, Ould El Mamy, Ahmed Bezeid, Héraud, Jean Michel, Filippone, Claudia, Ravalohery, Jean-Pierre, Chaabihi, Hassan, Albina, Emmanuel, Dommergues, Laure, Paweska, Janusz, and Cardinale, Eric
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Background: Rift Valley fever (RVF) is one of the main vector borne zoonotic diseases that affects a wide range of ruminants and human beings in Africa and the Arabian Peninsula. A rapid and specific test for RVF diagnosis at the site of a suspected outbreak is crucial for the implementation of control measures. Methodology/Principal findings: A first-line lateral flow immunochromatographic strip test (LFT) was developed for the detection of the nucleoprotein (N) of the RVF virus (RVFV). Its diagnostic performance characteristics were evaluated using reference stocks isolates recovered from different hosts and in geographic regions mimicking clinical specimens and from known RVF negative serum samples. A high level of diagnostic accuracy (DSe (35/35), DSp (167/169)) was observed, including the absence of cross-reactivity with viruses belonging to different genera. Conclusion/Significance: The fact no specialized reagents and laboratory equipment are needed, make this assay a valuable, first-line diagnostic tool in resource-poor diagnostic territories for on-site RVFV detection, however the staff require training. Author: summary: Rift Valley fever (RVF) is a viral disease that affects a wide range of animals and human beings in Africa and the Arabian Peninsula involving low case fatality rates. A rapid and specific test for RVF diagnosis at the site of a suspected outbreak is crucial for the implementation of control measures. Here, we report the development and the evaluation of the diagnostic performance characteristics of a pen-side test found to be a highly accurate and valuable first-line diagnostic tool for on-site RVF detection.
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- 2019
16. Prevalence and risk factors associated with West Nile virus infection in horses and wild birds in Madagascar
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Guis, Hélène, Raveloarijaona, B.N., Rasamoelina, V.M., Rakotoharinome, Vincent Michel, Rabarisoa, R., Raveloson, B., Razafindralambo, J.R., Ravaomanana, Julie, Cetre-Sossah, Catherine, Kantorovitch, V., Lancelot, Renaud, Beck, Cécile, Lecollinet, Sylvie, Ravaomanana, Fleurette, Randriamparany, Tantely, Raliniaina, Modestine, Filippone, C., Héraud, Jean Michel, and Cardinale, Eric
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viruses - Abstract
Objective: West Nile virus (WNV) is considered as the most prevalent arbovirus in Madagascar, yet few studies have focused on WNV circulation in wild birds and horses. The aims of this study are (i) to provide recent estimates of WNV seroprevalence and incidence in horses, (ii) to assess which wild bird species are exposed to WNV and (iii) to identify risk factors associated with exposure in horses and wild birds. Materials and methods: Horses from 4 regions of Madagascar were sampled before and after the 2015-2016 rainy season to estimate prevalence and incidence. Stable and horse characteristics were collected through a questionnaire. A wide range of wild birds species from the same regions were sampled in 2016-2017. Antibodies against WNV in horses and birds were tested using a competition ELISA test; results of a subset of samples were further confirmed using either a specific microsphere immunoassay for horses or a viral neutralization assay for birds. Logistic models were developed to identify risk factors. Results: Overall seroprevalence in horses was 33.5% (n=254) and incidence during the rainy season was 8.8% (n=147). Age, presence of ponds, use of insecticides and combined presence of rice fields and ruminants in the vicinity of stables were identified as risk factors. Overall, 352 birds (belonging to 41 species) were tested and 12.5% (belonging to 19 species) were seropositive. Birds caught outside wetlands, in Alaotra Mangoro region, belonging to the Passeriformes order, and species with an area of distribution in the Indian Ocean islands were significantly more exposed to WNV. Conclusion: This study confirms that WNV is endemic with high levels of circulation in horses, although no clinical cases were recorded. For the first time in Madagascar, 19 species of wild birds (among which 12 of the 21 Passeriformes species) were shown to be exposed to WNV.
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- 2018
17. Development and validation of a pen side test for Rift Valley fever
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Cêtre-Sossah, Catherine, primary, Pédarrieu, Aurélie, additional, Juremalm, Mikael, additional, Jansen Van Vuren, Petrus, additional, Brun, Alejandro, additional, Ould EL Mamy, Ahmed Bezeid, additional, Héraud, Jean-Michel, additional, Filippone, Claudia, additional, Ravalohery, Jean-Pierre, additional, Chaabihi, Hassan, additional, Albina, Emmanuel, additional, Dommergues, Laure, additional, Paweska, Janusz, additional, and Cardinale, Eric, additional
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- 2019
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18. Study on causes of fever in primary healthcare center uncovers pathogens of public health concern in Madagascar
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Guillebaud, Julia, primary, Bernardson, Barivola, additional, Randriambolamanantsoa, Tsiry Hasina, additional, Randrianasolo, Laurence, additional, Randriamampionona, Jane Léa, additional, Marino, Cesare Augusto, additional, Rasolofo, Voahangy, additional, Randrianarivelojosia, Milijaona, additional, Vigan-Womas, Ines, additional, Stivaktas, Voula, additional, Venter, Marietjie, additional, Piola, Patrice, additional, and Héraud, Jean-Michel, additional
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- 2018
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19. Both hemispheric influenza vaccine recommendations would have missed near half of the circulating viruses in Madagascar
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Guillebaud, Julia, primary, Héraud, Jean-Michel, additional, Razanajatovo, Norosoa H., additional, Livinski, Alicia A., additional, and Alonso, Wladimir J., additional
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- 2017
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20. GeneXpert for the diagnosis of COVID-19 in LMICs
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Rakotosamimanana, Niaina, Randrianirina, Frédérique, Randremanana, Rindra, Raherison, Mamy S, Rasolofo, Voahangy, Solofomalala, Gaetan D, Spiegel, André, and Heraud, Jean-Michel
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- 2020
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21. Prevalence of chronic hepatitis B virus infection and infrastructure for its diagnosis in Madagascar: Implication for the WHO's elimination strategy
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Andriamandimby, Soa Fy, Olive, Marie-Marie, Shimakawa, Yusuke, Rakotomanana, Fanjasoa, Razanajatovo, Iony Manitra, Andrianinarivomanana, Tsarasoa Malala, Ravalohery, Jean-Pierre, Andriamamonjy, Seta, Rogier, Christophe, Héraud, Jean Michel, Andriamandimby, Soa Fy, Olive, Marie-Marie, Shimakawa, Yusuke, Rakotomanana, Fanjasoa, Razanajatovo, Iony Manitra, Andrianinarivomanana, Tsarasoa Malala, Ravalohery, Jean-Pierre, Andriamamonjy, Seta, Rogier, Christophe, and Héraud, Jean Michel
- Abstract
Background: WHO developed a global strategy to eliminate hepatitis B by 2030 and set target to treat 80% of people with chronic hepatitis B virus (HBV) infection eligible for antiviral treatment. As a first step to achieve this goal, it is essential to conduct a situation analysis that is fundamental to designing national hepatitis plans. We therefore estimated the prevalence of chronic HBV infection, and described the existing infrastructure for HBV diagnosis in Madagascar. Methods: We conducted a stratified multi-stage serosurvey of hepatitis B surface antigen (HBsAg) in adults aged ≥18 years using 28 sentinel surveillance sites located throughout the country. We obtained the list of facilities performing HBV testing from the Ministry of Health, and contacted the person responsible at each facility. Results A total of 1778 adults were recruited from the 28 study areas. The overall weighted seroprevalence of HBsAg was 6.9% (95% CI: 5.6–8.6). Populations with a low socio-economic status and those living in rural areas had a significantly higher seroprevalence of HBsAg. The ratio of facilities equipped to perform HBsAg tests per 100,000 inhabitants was 1.02 in the capital city of Antananarivo and 0.21 outside the capital. There were no facilities with the capacity to perform HBV DNA testing or transient elastography to measure liver fibrosis. There are only five hepatologists in Madagascar. Conclusion: Madagascar has a high-intermediate level of endemicity for HBV infection with a severely limited capacity for its diagnosis and treatment. Higher HBsAg prevalence in rural or underprivileged populations underlines the importance of a public health approach to decentralize the management of chronic HBV carriers in Madagascar by using simple and low-cost diagnostic tools.
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- 2017
22. Reconstruction of Rift Valley fever transmission dynamics in Madagascar: Estimation of force of infection from seroprevalence surveys using Bayesian modelling
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Olive, Marie-Marie, Grosbois, Vladimir, Tran, Annelise, Nomenjanahary, Lalaina Arivony, Rakotoarinoro, Mihaja, Andriamandimby, Soa Fy, Rogier, Christophe, Héraud, Jean Michel, Chevalier, Véronique, Olive, Marie-Marie, Grosbois, Vladimir, Tran, Annelise, Nomenjanahary, Lalaina Arivony, Rakotoarinoro, Mihaja, Andriamandimby, Soa Fy, Rogier, Christophe, Héraud, Jean Michel, and Chevalier, Véronique
- Abstract
The force of infection (FOI) is one of the key parameters describing the dynamics of transmission of vector-borne diseases. Following the occurrence of two major outbreaks of Rift Valley fever (RVF) in Madagascar in 1990–91 and 2008–09, recent studies suggest that the pattern of RVF virus (RVFV) transmission differed among the four main eco-regions (East, Highlands, North-West and South-West). Using Bayesian hierarchical models fitted to serological data from cattle of known age collected during two surveys (2008 and 2014), we estimated RVF FOI and described its variations over time and space in Madagascar. We show that the patterns of RVFV transmission strongly differed among the eco-regions. In the North-West and Highlands regions, these patterns were synchronous with a high intensity in mid-2007/mid-2008. In the East and South-West, the peaks of transmission were later, between mid-2008 and mid-2010. In the warm and humid northwestern eco-region favorable to mosquito populations, RVFV is probably transmitted all year-long at low-level during inter-epizootic period allowing its maintenance and being regularly introduced in the Highlands through ruminant trade. The RVF surveillance of animals of the northwestern region could be used as an early warning indicator of an increased risk of RVF outbreak in Madagascar.
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- 2017
23. Joint analysis of human and bovine serological data: new insight on the risk and mechanisms of transmission of Rift Valley fever in Madagascar. [260]
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Olive, Marie-Marie, Héraud, Jean Michel, Grosbois, Vladimir, Andriamandimby, Soa Fy, Tran, Annelise, Rakotomanana, Fanjasoa, Rogier, Christophe, and Chevalier, Véronique
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C30 - Documentation et information ,000 - Autres thèmes ,L73 - Maladies des animaux - Abstract
Purpose: In 2008-09, an outbreak of Rift Valley fever (RVF) virus occurred in Madagascar. Spatial heterogeneity in seroprevalence (SP) and case occurrence frequencies suggested that some areas are more favorable to RVF circulation. The objectives of our study were to identify environmental factors in favor to human and cattle infections; test the relevance of using local cattle infection as human infection predictor and give a new insight on the respective role of direct and vectorial transmission both in human and cattle. Methods: We used 2 independent cattle and human serological datasets originating from two national surveys (2009 and 2011-13). Multiple Factor Analysis (MFA) was used to characterize environments of the whole island in terms of climate and landscape. The datasets were analyzed independently using a generalized linear mixed model (GLMM) with the individual serological status- human or cattle- as the binomial response. Explicative variables were age and MFA factors for cattle model (M1) and age, gender, MFA factors and contact with ruminants and their product for human model (M2). Then human and cattle data were analyzed jointly by GLMM with the human individual status as binomial response. In addition to the previous explicative variables cattle SP predicted by M1 was used. Models accuracies were tested using ROC curve method. Results: Four MFA factors were selected. Age and factor4 - humid (irrigation, lake, marshland) environment - had a positive effect on SP of cattle and human living in rural areas (p
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- 2016
24. Prevalence of chronic hepatitis B virus infection and infrastructure for its diagnosis in Madagascar: implication for the WHO’s elimination strategy
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Andriamandimby, Soa Fy, primary, Olive, Marie-Marie, additional, Shimakawa, Yusuke, additional, Rakotomanana, Fanjasoa, additional, Razanajatovo, Iony Manitra, additional, Andrianinarivomanana, Tsarasoa Malala, additional, Ravalohery, Jean-Pierre, additional, Andriamamonjy, Seta, additional, Rogier, Christophe, additional, and Héraud, Jean-Michel, additional
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- 2017
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25. High prevalence of west Nile virus in domestic birds and detection in 2 new mosquito species in Madagascar
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Maquart, Marianne, Boyer, Sébastien, Rakotoharinome, Vincent Michel, Ravaomanana, Julie, Tantely, Luciano Michaël, Héraud, Jean Michel, Cardinale, Eric, Maquart, Marianne, Boyer, Sébastien, Rakotoharinome, Vincent Michel, Ravaomanana, Julie, Tantely, Luciano Michaël, Héraud, Jean Michel, and Cardinale, Eric
- Abstract
West Nile virus is an arthropod-borne zoonosis transmitted by a large number of mosquito species, and birds play a key role as reservoir of the virus. Its distribution is largely widespread over Africa, Asia, the Americas and Europe. Since 1978, it has frequently been reported in Madagascar. Studies described a high seroprevalence level of the virus in humans in different areas of the island and a human fatal case of WNV infection was reported in 2011. Despite these reports, the epidemiology of WNV in Madagascar, in particular, viral circulation remains unclear. To explore the transmission of WNV in two rural human populations of Madagascar, we investigated local mosquitoes and poultry for evidence of current infections, and determined seroprevalence of candidate sentinel species among the local poultry. These 2 areas are close to lakes where domestic birds, migratory wild birds and humans coexist. Serological analysis revealed WNV antibodies in domestic birds (duck, chicken, goose, turkey and guinea fowl) sampled in both districts (Antsalova 29.4% and Mitsinjo 16.7%). West Nile virus nucleic acid was detected in one chicken and in 8 pools of mosquitoes including 2 mosquito species (Aedeomyia madagascarica and Anopheles pauliani) that have not been previously described as candidate vectors for WNV. Molecular analysis of WNV isolates showed that all viruses detected were part of the lineage 2 that is mainly distributed in Africa, and were most closely matched by the previous Malagasy strains isolated in 1988. Our study showed that WNV circulates in Madagascar amongst domestic birds and mosquitoes, and highlights the utility of poultry as a surveillance tool to detect WNV transmission in a peri-domestic setting.
- Published
- 2016
26. Integrated analysis of environment, cattle and human serological data: Risks and mechanisms of transmission of rift valley fever in Madagascar
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Olive, Marie-Marie, Chevalier, Véronique, Grosbois, Vladimir, Tran, Annelise, Andriamandimby, Soa Fy, Durand, Benoit, Ravalohery, Jean-Pierre, Andriamamonjy, Seta, Rakotomanana, Fanjasoa, Rogier, Christophe, Héraud, Jean Michel, Olive, Marie-Marie, Chevalier, Véronique, Grosbois, Vladimir, Tran, Annelise, Andriamandimby, Soa Fy, Durand, Benoit, Ravalohery, Jean-Pierre, Andriamamonjy, Seta, Rakotomanana, Fanjasoa, Rogier, Christophe, and Héraud, Jean Michel
- Abstract
Background: Rift Valley fever (RVF) is a vector-borne disease affecting ruminants and humans. Madagascar was heavily affected by RVF in 2008–2009, with evidence of a large and heterogeneous spread of the disease. The identification of at-risk environments is essential to optimize the available resources by targeting RVF surveillance in Madagascar. Herein, the objectives of our study were: (i) to identify the environmental factors and areas favorable to RVF transmission to both cattle and human and (ii) to identify human behaviors favoring human infections in Malagasy contexts. Methodology/Principal Findings: First, we characterized the environments of Malagasy communes using a Multiple Factor Analysis (MFA). Then, we analyzed cattle and human serological data collected at national level using Generalized Linear Mixed Models, with the individual serological status (cattle or human) as the response, and MFA factors, as well as other potential risk factors (cattle density, human behavior) as explanatory variables. Cattle and human seroprevalence rates were positively associated to humid environments (p<0.001). Areas with high cattle density were at risk (p<0.01; OR = 2.6). Furthermore, our analysis showed that frequent contact with raw milk contributed to explain human infection (OR = 1.6). Finally, our study highlighted the eastern-coast, western and north-western parts as high-risk areas for RVF transmission in cattle. Conclusions/Significance: Our integrated approach analyzing environmental, cattle and human datasets allow us to bring new insight on RVF transmission patterns in Madagascar. The association between cattle seroprevalence, humid environments and high cattle density suggests that concomitant vectorial and direct transmissions are critical to maintain RVF enzootic transmission. Additionally, in the at-risk humid environment of the western, north-western and the eastern-coast areas, suitable to Culex and Anopheles mosquitoes, vectorial transmission probabl
- Published
- 2016
27. Global circulation of respiratory viruses: from local observations to global predictions
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Heraud, Jean-Michel, Razanajatovo, Norosoa Harline, and Viboud, Cecile
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- 2019
- Full Text
- View/download PDF
28. Rift Valley Fever in human and ruminants in the different ecosystems of Madagascar
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Olive, Marie-Marie, Chevalier, Véronique, Andriamandimby, Soa Fy, Rakotomanana, Fanjasoa, Grosbois, Vladimir, Tran, Annelise, Rogier, Christophe, and Héraud, Jean Michel
- Subjects
S50 - Santé humaine ,L73 - Maladies des animaux - Published
- 2014
29. Rift Valley fever in a temperate and mountaneous area of Madagascar
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Chevalier, Véronique, Rakotondrafara, Toky, Jourdan, Marion, Héraud, Jean Michel, Rasamoelina, H., Durand, Benoit, Ravaomanana, Julie, Rollin, Pierre E., and Rakotondravao, René
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L73 - Maladies des animaux - Abstract
A serological study was performed in 2009 in Madagascar highlands to evaluate the point prevalence rate of RVF antibodies in ruminants and identify environmental and trade factors potentially linked to RVF persistence and transmission. Nine hundred ruminants were randomly selected among 51 villages and sampled. Sera were analysed using a commercial validated ELISA test. For each ruminant, the following variables were recorded: age, location of the night pen, minimum distance from the pen to the closest water point and the forest, water point type, and the way owners use to renewal their herd: auto-renewal vs purchase. Serological data were analysed using a generalized linear mixed model, the individual serological status being the binomial response, and the above-mentioned variables the explicative factors, and the breeder as random effect. The overall IgG seroprevalence rate was 28% [IC95% 25-31]. The main effect on prevalence was due to age (P=10-4) suggesting an endemic RVF circulation in this area. The distance to the closest water point was a protective factor (P=5×10-3) but the type of water point had no effect on the prevalence rate: a substantial part of the transmission is due to vectors and several mosquito species are probably involved. Ruminants belonging to owners renewing their herd by purchase were significantly more infected than others (P=0.04), suggesting that cattle trade may contribute to the circulation of the virus in this area. This is the first evidence of a recurrent transmission of RVFV in such an ecosystem which associates a wet, temperate climate, high altitude, paddy fields, and vicinity to a dense rain forest. Persistence mechanisms need to be further investigated. (Texte intégral)
- Published
- 2012
30. Etudes sur la Fièvre de la Vallée du Rift à Madagascar : comprendre les mécanismes de persistance et diffusions du virus
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Rakotoharinome, Vincent Michel, Olive, Marie-Marie, Ravaomanana, Julie, Rakotondravao, René, Andriamanampy, Nomena, Rasolofoniaina, Jonia, Rafisandrantantsoa, Jean-Théophile, Nepomichene, Thiery Nirina Jean Jose, Andrianaivolambo, Lala, Ratsimandresy, Nasolo, Roger, Matthieu, Maquart, Marianne, Elissa, Nohal, Héraud, Jean Michel, and Cardinale, Eric
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E70 - Commerce, commercialisation et distribution ,L73 - Maladies des animaux ,L72 - Organismes nuisibles des animaux - Abstract
Introduction : A Madagascar, les premières épidémies et épizooties de Fièvre de la Vallée du Rift (FVR) ont été rapportées en 1990-1991. A la suite des épidémies et épizooties de FVR en Afrique de l'Est en 2006-2007, la FVR a été détectée dans les îles du sud ouest de l'Océan Indien (Union des Comores, Madagascar) en 2007 et 2008. A Madagascar, le premier cas humain a été détecté en Janvier 2008 suivi de nombreux cas humains et animaux jusqu'en mars 2009. Des études rétrospectives ont montré que le VFVR avait largement circulé dans le pays depuis 2007. Au cours d'une épidémie, des moustiques ont été collectés autour des cas et des pools de femelles non gorgées composées d'Anopheles coustani, Anopheles squamosus/cydippis et Culex antennatus ont été trouvé infectés par le VFVR, suggérant que ces espèces auraient pu jouer un rôle dans la transmission du virus. Les analyses phylogénétiques des souches ayant circulé lors des épisodes de 2008-2009 ont montré que le virus était génétiquement proche de celui ayant circulé en 2006-2007 au Kenya suggérant une nouvelle introduction du virus à Madagascar depuis l'Afrique de l'Est. Les mécanismes d'introduction, de maintenance et de diffusion du VFVR à Madagascar restent à élucider. Pour une meilleure compréhension de ces mécanismes, plusieurs études ont été mises en place dans le cadre du programme de coopération scientifique sur les maladies émergentes dans l'Océan Indien (OI) : le PCSMAE AnimalRisk avec pour objectifs (i) détecter une circulation à bas-bruit du VFVR, (ii) déterminer les espèces de moustiques pouvant être impliquées dans cette circulation à bas-bruit, (iii) déterminer si le virus circulant actuellement est génétiquement similaire à celui circulant en 2008-2009 et enfin (iv) identifier des facteurs de risque et les mécanismes associés à cette circulation et à la dissémination de VRFV à Madagascar, (v) étudier les flux de ruminant à l'intérieur du pays et entre les îles du sud ouest de l'OI Méthodes : Un troupeau sentinelle a été mis en place dans deux zones agro-écologiques différentes à Tuléar (Sud) et Mampikony (Nord-Ouest). Cent cinquante zébus (60 à Mampikony et 90 à Tulear) âgés de 6 mois à 13 mois au début de l'étude ont été identifiés et prélevés mensuellement. Les prélèvements de sérums ont été testés pour une recherche en Immunoglobuline (Ig) M et Ig G dirigées contre le VFVR par ELISA sandwich et ELISA indirect respectivement. Des captures entomologiques ont été organisées dans les sites d'étude en mai et septembre 2010 et mars 2011 pour Tuléar ainsi qu'en avril 2010 et avril 2011 à Mampikony. Enfin une étude sur les flux commerciaux de ruminants dans le pays et entre les îles de l'OI a été menée. Résultats : Durant la période d'étude 53 animaux ont été détectés positifs en IgM dirigées contre le VFVR, traduisant une circulation récente du VFVR. Le nombre d'animaux positif en IgM est plus élevé à Tuléar qu'à Mampikony (respectivement 38 et 15 animaux). Le pic de nouveaux individus en contact avec le VFVR est situé en janvier 2011. La détection du VFVR par RT-PCR dans les sérums récoltés est en cours. Les enquêtes menées dans les ports situés au nord et au nord ouest de Madagascar ne nous ont pas permises d'identifier des importations illicites d'animaux vivants ou denrées alimentaires d'origine animale (DAOA) depuis l'Afrique de l'Est ou l'Archipel des Comores. En revanche, nos enquêtes nous ont permis de déterminer que des exportations de bovins avaient eu lieu depuis le port de Manjunga à destinations des Comores. L'étude sur les flux de bovins dans le pays, nous a permis de déterminer et quantifier les flux d'animaux entrant et sortant des marchés à zébus d'Ambalavao, Ihosy et Ampanotonkana et les flux entrant à Antananarivo. Au total, 10 849 moustiques dont 5 genres et 31 espèces à Mampikony et 5 706 moustiques dont 4 genres et 16 espèces à Tuléar ont été identifiés. En 2010, les vecteurs potentiels (seules les trois espèces citées plus haut sont concernées)
- Published
- 2011
31. Fièvre de la Vallée du Rift : Les Comores: porte d'entrée du virus?
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Roger, Matthieu, Foray, Coralie, Licciardi, Séverine, Maquart, Marianne, Halifa, Mohamed, Olive, Marie-Marie, Girard, Sébastien, Faharoudine, Abdourahime, Héraud, Jean Michel, and Cardinale, Eric
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L01 - Elevage - Considérations générales ,E70 - Commerce, commercialisation et distribution ,L73 - Maladies des animaux - Abstract
Identifié à Madagascar depuis 1979, le virus de la Fièvre de la Vallée du Rift (FVR) provoque régulièrement épidémies et épizooties dans la région Océan Indien. Lancé en 2009, le programme "AnimalRisk" a déjà mis en évidence lors de sa première phase, un passage important du virus dans la région et notamment dans tout l'archipel des Comores pour lequel aucune information n'était connue à ce jour. En effet, plus d'un ruminant comorien sur trois prélevé a été testé positif à la recherche d'anticorps anti-FVR. La prévalence globale de la maladie est de 32.8% (28.6% - 36.9%) et varie en fonction des îles avec Anjouan 26.6% (20.0% - 33,3%), Grande Comore 34.3% (28,7% - 40,0%) et Mohéli 45.8% (31.7% - 59.9%). Cette nouvelle donnée, aussi importante, méritait d'être complétée afin de savoir si le virus était toujours présent dans l'archipel. L'importation régulière de ruminants tanzaniens par l'Union des Comores ainsi que les échanges formels et informels de personnes et d'animaux entre les îles de la zone sont des risques d'introduction ou de réintroduction des pathogènes et notamment du virus de la FVR. Plus encore, les facteurs potentiels d'endémisation de la maladie doivent être identifiés et caractérisés afin d'évaluer le risque d'apparition de futures épidémies ou épizooties. Pour répondre à ces questions, un large dispositif a été mis en place lors de la seconde phase du programme " AnimalRisk "dans tous les pays de l'Océan Indien affectés par cette maladie. Pour deux zones de Madagascar, cinq de Mayotte et quatre de l'Union des Comores, des animaux sentinelles ont été identifiés et un suivi sérologique et virologique a été réalisé pendant au moins un an. Des nouvelles données sur les flux d'animaux ont été également collectées suite à la mise en place d'un suivi mensuel des échanges au niveau des points d'entrées/sorties probables d'animaux dans les îles de l'archipel des Comores. En parallèle, la caractérisation du milieu ainsi que des pratiques d'élevage et de commercialisation a été effectuée. Enfin, un suivi entomologique, mené en même temps que le suivi animal, a été réalisé sur les mêmes zones afin de recenser les espèces entomologiques hématophages et les vecteurs potentiels du virus de la FVR. Les résultats préliminaires de ce second volet du programme " AnimalRisk " vont tous dans le même sens. Le virus de la FVR est bien présent et circule en période interépidémique dans tous les pays de l'étude. Ainsi, pour la seule Union des Comores, sur une moyenne de 20 animaux suivis par site pour Anjouan et Mohéli et 35 pour la Grande Comore, onze animaux ont séroconverti. Les séroconversion ont été observées sur les trois îles mais l'incidence la plus élevée est observée à Mohéli avec 35.9% des animaux naïfs de l'étude ayant séroconverti sur 15 mois. (Texte intégral)
- Published
- 2011
32. Le réseau régional de surveillance AnimalRisk : de la surveillance à la recherche dans l'Océan Indien
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Cardinale, Eric, Roger, Matthieu, Elissa, N., Faharoudine, Abdourahime, Girard, S., Halifa, Mohamed, Jaumally, Mahmad Reshad, Héraud, Jean Michel, Lalaonirina, B.A., Laurette, S., Lasne, Laurent, Licciardi, Séverine, Maquart, Marianne, Melanie, Jimmie, Meenowa, Deodass, Olive, Marie-Marie, Rakotoharinome, Vincent Michel, Rakotondravao, M., and Ravaomanana, J.
- Subjects
C30 - Documentation et information ,Maladie des animaux ,Santé animale ,L70 - Sciences et hygiène vétérinaires - Considérations générales ,Surveillance épidémiologique ,L73 - Maladies des animaux ,Réseau de recherche - Abstract
Pour répondre aux défis lancés par les maladies émergentes dans l'Océan Indien, les acteurs de la santé animale ont mis en place depuis début 2009 le réseau AnimalRisk-OI. Ce réseau a pour objectif d'apporter un soutien technique et scientifique aux systèmes de surveillance et de proposer des réponses pour une meilleure gestion des risques sanitaires dans la zone. Les partenaires sont les référents de l'OIE dans l'Océan Indien, à savoir les services vétérinaires ainsi que les structures de recherche impliquées en santé animale. Le réseau AnimalRisk-OI n'a pas pour vocationde se substituer aux systèmes de surveillance existants, mais il est chargé d'animer une réflexion autour des problématiques observées par des téléweb conférences bimensuelles, des réunions annuelles et des bulletins d'information trimestriels et de nourrir des actions de recherche qui visent à mieux comprendre l'épidémiologie de certaines maladies et donc de proposer des mesures de gestion adéquates pour mieux les maîtriser. Les premiers résultats de la surveillance et des investigations sur certaines maladies considérées prioritaires par les partenaires sont présentés ici. Les orientations envisagées, outre la poursuite de la synergie entre les actions de surveillance et de recherche, sont un rapprochement avec la santé humaine pour permettre une approche commune et harmonisée de l'appréciation et de la gestion des risques sanitaires dans l'Océan Indien.
- Published
- 2011
33. Molecular Comparison and Evolutionary Analyses of VP1 Nucleotide Sequences of New African Human Enterovirus 71 Isolates Reveal a Wide Genetic Diversity
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Bessaud, Maël, primary, Razafindratsimandresy, Richter, additional, Nougairède, Antoine, additional, Joffret, Marie-Line, additional, Deshpande, Jagadish M., additional, Dubot-Pérès, Audrey, additional, Héraud, Jean-Michel, additional, de Lamballerie, Xavier, additional, Delpeyroux, Francis, additional, and Bailly, Jean-Luc, additional
- Published
- 2014
- Full Text
- View/download PDF
34. An unexpected recurrent transmission of rift valley fever virus in cattle in a temperate and mountainous area of Madagascar
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Chevalier, Véronique, Rakotondrafara, Toky, Jourdan, Marion, Héraud, Jean Michel, Andriamanivo, Harena Rasamoelina, Durand, Benoit, Ravaomanana, Julie, Rollin, Pierre E., Rakotondravao, René, Chevalier, Véronique, Rakotondrafara, Toky, Jourdan, Marion, Héraud, Jean Michel, Andriamanivo, Harena Rasamoelina, Durand, Benoit, Ravaomanana, Julie, Rollin, Pierre E., and Rakotondravao, René
- Abstract
Rift Valley fever is an acute, zoonotic viral disease of domestic ruminants, caused by a phlebovirus (Bunyaviridae family). A large outbreak occurred in Madagascar in 2008-2009. The goal of the present study was to evaluate the point prevalence of antibodies against Rift Valley Fever Virus (RVFV) in cattle in the Anjozorobe district, located in the wet and temperate highland region of Madagascar and yet heavily affected by the disease, and analyse environmental and trade factors potentially linked to RVFV transmission. A serological study was performed in 2009 in 894 bovines. For each bovine, the following variables were recorded: age, location of the night pen, minimum distance from the pen to the nearest water point and the forest, nearest water point type, and herd replacement practices. The serological data were analyzed using a generalized linear mixed model. The overall anti-RVFV IgG seroprevalence rate was 28% [CI95% 25-31]. Age was statistically linked to prevalence (p = 10?4), being consistent with a recurrent RVFV circulation. Distance from the night pen to the nearest water point was a protective factor (p = 5.10?3), which would be compatible with a substantial part of the virus transmission being carried out by nocturnal mosquito vectors. However, water point type did not influence the risk of infection: several mosquito species are probably involved. Cattle belonging to owners who purchase animals to renew the herd were significantly more likely to have seroconverted than others (p = 0.04): cattle trade may contribute to the introduction of the virus in this area. The minimum distance of the night pen to the forest was not linked to the prevalence. This is the first evidence of a recurrent transmission of RVFV in such an ecosystem that associates a wet, temperate climate, high altitude, paddy fields, and vicinity to a dense rain forest. Persistence mechanisms need to be further investigated.
- Published
- 2011
35. High Prevalence of Hepatitis E in Humans and Pigs and Evidence of Genotype-3 Virus in Swine, Madagascar
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Temmam, Sarah, primary, Foray, Coralie, additional, Dellagi, Koussay, additional, Pascalis, Hervé, additional, Porphyre, Vincent, additional, Rasamoelina-Andriamanivo, Harentsoaniaina, additional, Besnard, Lydia, additional, Pavio, Nicole, additional, Andriamandimby, Soa Fy, additional, Cardinale, Eric, additional, and Héraud, Jean-Michel, additional
- Published
- 2013
- Full Text
- View/download PDF
36. Surveillance and control of rabies in La Reunion, Mayotte, and Madagascar
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Andriamandimby, Soa, primary, Héraud, Jean-Michel, additional, Ramiandrasoa, Ravo, additional, Ratsitorahina, Maherisoa, additional, Rasambainarivo, Jhon H, additional, Dacheux, Laurent, additional, Lepelletier, Anthony, additional, Goodman, Steven M, additional, Reynes, Jean-Marc, additional, and Bourhy, Hervé, additional
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- 2013
- Full Text
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37. Introduction of rubella-containing-vaccine to Madagascar: implications for roll-out and local elimination
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Wesolowski, Amy, Mensah, Keitly, Brook, Cara E., Andrianjafimasy, Miora, Winter, Amy, Buckee, Caroline O., Razafindratsimandresy, Richter, Tatem, Andrew J., Heraud, Jean-Michel, and Metcalf, C. Jessica E.
- Subjects
rubella ,vaccination ,Madagascar ,congenital rubella syndrome ,evaluation of vaccination programmes ,Africa - Abstract
Few countries in Africa currently include rubella-containing vaccination (RCV) in their immunization schedule. The Global Alliance for Vaccines Initiative (GAVI) recently opened a funding window that has motivated more widespread roll-out of RCV. As countries plan RCV introductions, an understanding of the existing burden, spatial patterns of vaccine coverage, and the impact of patterns of local extinction and reintroduction for rubella will be critical to developing effective programmes. As one of the first countries proposing RCV introduction in part with GAVI funding, Madagascar provides a powerful and timely case study. We analyse serological data from measles surveillance systems to characterize the epidemiology of rubella in Madagascar. Combining these results with data on measles vaccination delivery, we develop an age-structured model to simulate rubella vaccination scenarios and evaluate the dynamics of rubella and the burden of congenital rubella syndrome (CRS) across Madagascar. We additionally evaluate the drivers of spatial heterogeneity in age of infection to identify focal locations where vaccine surveillance should be strengthened and where challenges to successful vaccination introduction are expected. Our analyses indicate that characteristics of rubella in Madagascar are in line with global observations, with an average age of infection near 7 years, and an impact of frequent local extinction with reintroductions causing localized epidemics. Modelling results indicate that introduction of RCV into the routine programme alone may initially decrease rubella incidence but then result in cumulative increases in the burden of CRS in some regions (and transient increases in this burden in many regions). Deployment of RCV with regular supplementary campaigns will mitigate these outcomes. Results suggest that introduction of RCV offers a potential for elimination of rubella in Madagascar, but also emphasize both that targeted vaccination is likely to be a lynchpin of this success, and the public health vigilance that this introduction will require.
- Published
- 2016
- Full Text
- View/download PDF
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