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Pepey A, Souris M, Kim S, Obadia T, Chy S, Ea M, Ouk S, Remoue F, Sovannaroth S, Mueller I, Witkowski B, Vantaux A. Comparing malaria risk exposure in rural Cambodia population using GPS tracking and questionnaires. Malar J 2024; 23:75. [PMID: 38475843 DOI: 10.1186/s12936-024-04890-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 02/23/2024] [Indexed: 03/14/2024] Open
Abstract
BACKGROUND The Great Mekong Subregion has attained a major decline in malaria cases and fatalities over the last years, but residual transmission hotspots remain, supposedly fueled by forest workers and migrant populations. This study aimed to: (i) characterize the fine-scale mobility of forest-goers and understand links between their daily movement patterns and malaria transmission, using parasites detection via real time polymerase chain reaction (RT PCR) and the individual exposure to Anopheles bites by quantification of anti-Anopheles saliva antibodies via enzyme-linked immunosorbent assay; (ii) assess the concordance of questionnaires and Global Positioning System (GPS) data loggers for measuring mobility. METHODS Two 28 day follow-ups during dry and rainy seasons, including a GPS tracking, questionnaires and health examinations, were performed on male forest goers representing the population at highest risk of infection. Their time spent in different land use categories and demographic data were analyzed in order to understand the risk factors driving malaria in the study area. RESULTS Malaria risk varied with village forest cover and at a resolution of only a few kilometers: participants from villages outside the forest had the highest malaria prevalence compared to participants from forest fringe's villages. The time spent in a specific environment did not modulate the risk of malaria, in particular the time spent in forest was not associated with a higher probability to detect malaria among forest-goers. The levels of antibody response to Anopheles salivary peptide among participants were significantly higher during the rainy season, in accordance with Anopheles mosquito density variation, but was not affected by sociodemographic and mobility factors. The agreement between GPS and self-reported data was only 61.9% in reporting each kind of visited environment. CONCLUSIONS In a context of residual malaria transmission which was mainly depicted by P. vivax asymptomatic infections, the implementation of questionnaires, GPS data-loggers and quantification of anti-saliva Anopheles antibodies on the high-risk group were not powerful enough to detect malaria risk factors associated with different mobility behaviours or time spent in various environments. The joint implementation of GPS trackers and questionnaires allowed to highlight the limitations of both methodologies and the benefits of using them together. New detection and follow-up strategies are still called for.
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Affiliation(s)
- Anaïs Pepey
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, 5 Blvd Monivong, Phnom Penh 120 210, Phnom Penh, BP983, Cambodia.
| | - Marc Souris
- UMR Unité des Virus Emergents, UVE: Aix-Marseille Univ-IRD 190-Inserm 1207-IHU 5 Méditerranée Infection, 13005, Marseille, France
| | - Saorin Kim
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, 5 Blvd Monivong, Phnom Penh 120 210, Phnom Penh, BP983, Cambodia
| | - Thomas Obadia
- Institut Pasteur, G5 Infectious Disease Epidemiology and Analytics, Université Paris Cité, 75015, Paris, France
- Institut Pasteur, Bioinformatics and Biostatistics Hub, Université Paris Cité, 75015, Paris, France
| | - Sophy Chy
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, 5 Blvd Monivong, Phnom Penh 120 210, Phnom Penh, BP983, Cambodia
| | - Malen Ea
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, 5 Blvd Monivong, Phnom Penh 120 210, Phnom Penh, BP983, Cambodia
| | - Sivkeng Ouk
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, 5 Blvd Monivong, Phnom Penh 120 210, Phnom Penh, BP983, Cambodia
| | - Franck Remoue
- UMR MIVEGEC, IRD, CNRS, University of Montpellier, Montpellier, France
| | - Siv Sovannaroth
- National Centre for Parasitology Entomology and Malaria Control (CNM), Phnom Penh 120 801, Phnom Penh, Cambodia
| | - Ivo Mueller
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Benoit Witkowski
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, 5 Blvd Monivong, Phnom Penh 120 210, Phnom Penh, BP983, Cambodia
- Genetic and Biology of Plasmodium Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar
| | - Amélie Vantaux
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, 5 Blvd Monivong, Phnom Penh 120 210, Phnom Penh, BP983, Cambodia
- Genetic and Biology of Plasmodium Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar
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Guindo-Coulibaly N, Kpan MDS, Adja AM, Kouadio AMN, Assouho KF, Zoh DD, Azongnibo KRM, Remoue F, Fournet F. Seasonal variation and intra urban heterogeneity of the entomological risk of transmission of dengue and yellow fever in Abidjan, Côte d'Ivoire. Med Vet Entomol 2022; 36:329-337. [PMID: 35352845 DOI: 10.1111/mve.12571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 01/31/2022] [Accepted: 03/10/2022] [Indexed: 06/14/2023]
Abstract
Dengue and yellow fever are prevalent in Côte d'Ivoire and Aedes (Stegomyia) aegypti (Linnaeus), (Diptera: Culicidae), is known as the main vector. We aimed to assess seasonal variation and spatial heterogeneity in the transmission of both arbovirus diseases in Abidjan. Entomological surveys targeting larvae of A. aegypti, were carried out between November 2015 and August 2016 covering the four climatic seasons including a cohort of 100 houses randomly selected in three neighbourhoods. A. aegypti was the predominant species (96.6%) of mosquitoes resulting from the rearing of harvested larvae, and the only vector of dengue and yellow fever recorded during the study period. The highest proportion of water storage containers (45.5%) which represented the major breeding sites infested by the larvae of A. aegypti, was observed in Anoumabo. The house indices >5% and/or Breteau indices >20 recorded in each neighbourhood, during the different climatic seasons, indicated that there was, a high and permanent, heterogeneity in the transmission risk of dengue and yellow fever between the three neighbourhoods. In terms of transmission risk, Anoumabo was the neighbourhood with the highest risk compared to the two others, then, particular attention should be paid to this site in terms of surveillance by vector control programme in Abidjan.
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Affiliation(s)
- Négnorogo Guindo-Coulibaly
- Laboratoire de Biologie et Santé, Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Mintokapieu Didier Stephane Kpan
- Laboratoire de Biologie et Santé, Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
- Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Akré Maurice Adja
- Laboratoire de Biologie et Santé, Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
- Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Affoué Mireille Nadia Kouadio
- Laboratoire de Biologie et Santé, Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
- Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Konan Fabrice Assouho
- Laboratoire de Biologie et Santé, Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
- Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Dounin Danielle Zoh
- Laboratoire de Biologie et Santé, Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
- Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Konan Rodolphe Mardoché Azongnibo
- Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
- Institut de Géographie Tropicale, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Franck Remoue
- Institut de Recherches pour le Développement centre de Montpellier, UMR MIVEGEC (Université de Montpellier, IRD, CNRS), Montpellier, France
| | - Florence Fournet
- Institut de Recherches pour le Développement centre de Montpellier, UMR MIVEGEC (Université de Montpellier, IRD, CNRS), Montpellier, France
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Zamble BZH, Yao SS, Adja AM, Bakli M, Zoh DD, Mathieu-Daudé F, Assi SB, Remoue F, Almeras L, Poinsignon A. First evaluation of antibody responses to Culex quinquefasciatus salivary antigens as a serological biomarker of human exposure to Culex bites: A pilot study in Côte d'Ivoire. PLoS Negl Trop Dis 2021; 15:e0010004. [PMID: 34898609 PMCID: PMC8699949 DOI: 10.1371/journal.pntd.0010004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 12/23/2021] [Accepted: 11/17/2021] [Indexed: 12/03/2022] Open
Abstract
Background Culex mosquitoes are vectors for a variety of pathogens of public health concern. New indicators of exposure to Culex bites are needed to evaluate the risk of transmission of associated pathogens and to assess the efficacy of vector control strategies. An alternative to entomological indices is the serological measure of antibodies specific to mosquito salivary antigens. This study investigated whether the human IgG response to both the salivary gland extract and the 30 kDa salivary protein of Culex quinquefasciatus may represent a proxy of human exposure to Culex bites. Methodology/Principal findings A multidisciplinary survey was conducted with children aged 1 to 14 years living in neighborhoods with varying exposure to Culex quinquefasciatus in the city of Bouaké, Côte d’Ivoire. Children living in sites with high exposure to Cx quinquefasciatus had a significantly higher IgG response to both salivary antigens compared with children living in the control site where only very few Culex were recorded. Moreover, children from any Culex-high exposed sites had significantly higher IgG responses only to the salivary gland extract compared with children from the control village, whereas no difference was noted in the anti-30 kDa IgG response. No significant differences were noted in the specific IgG responses between age and gender. Sites and the use of a bed net were associated with the level of IgG response to the salivary gland extract and to the 30 kDa antigen, respectively. Conclusions/Significance These findings suggest that the IgG response to Culex salivary gland extracts is suitable as proxy of exposure; however, the specificity to the Culex genus needs further investigation. The lower antigenicity of the 30 kDa recombinant protein represents a limitation to its use. The high specificity of this protein to the Culex genus makes it an attractive candidate and other specific antibody responses might be more relevant as a biomarker of exposure. These epidemiological observations may form a starting point for additional work on developing serological biomarkers of Culex exposure. The evaluation of exposure to mosquitoes is a key parameter in assessing the risk of transmission of associated pathogens, including zoonoses. Entomological methods represent the gold standard but have several limitations, and efforts are being made to develop new indicators to accurately assess human–Culex contact. This study showed the IgG response to Culex quinquefasciatus salivary gland extract is suitable proxy of exposure to Culex bites. The lower antigenicity of the 30 kDa recombinant protein represents a limitation to its use. The high specificity of this protein to the Culex genus makes it an attractive candidate and other isotypic antibody responses specific to this salivary antigen might be more relevant as a biomarker of exposure.
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Affiliation(s)
- Bi Zamble H. Zamble
- Institut Pierre Richet / Institut National de Santé Publique, Bouaké, Côte d’Ivoire
- MIVEGEC, University of Montpellier, IRD, CNRS, Montpellier, France
- * E-mail:
| | - Serge S. Yao
- Institut Pasteur de Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Akré M. Adja
- Institut Pierre Richet / Institut National de Santé Publique, Bouaké, Côte d’Ivoire
- UFR Biosciences, University Felix Houphouët Boigny, Abidjan, Côte d’Ivoire
| | | | - Dounin D. Zoh
- Institut Pierre Richet / Institut National de Santé Publique, Bouaké, Côte d’Ivoire
- UFR Biosciences, University Felix Houphouët Boigny, Abidjan, Côte d’Ivoire
| | | | - Serge B. Assi
- Institut Pierre Richet / Institut National de Santé Publique, Bouaké, Côte d’Ivoire
- Programme National de Lutte contre le Paludisme, Abidjan, Côte d’Ivoire
| | - Franck Remoue
- MIVEGEC, University of Montpellier, IRD, CNRS, Montpellier, France
| | - Lionel Almeras
- IHU Méditerranée Infection, Marseille, France
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France
- Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France
| | - Anne Poinsignon
- Institut Pierre Richet / Institut National de Santé Publique, Bouaké, Côte d’Ivoire
- MIVEGEC, University of Montpellier, IRD, CNRS, Montpellier, France
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Kpan MDS, Adja AM, Guindo-Coulibaly N, Assouho KF, Kouadio AMN, Azongnibo KRM, Zoh DD, Zahouli BZJ, Remoue F, Fournet F. Spatial Heterogeneity and Seasonal Distribution of Aedes ( Stegomyia) aegypti (L) in Abidjan, Côte d'Ivoire. Vector Borne Zoonotic Dis 2021; 21:769-776. [PMID: 34252330 DOI: 10.1089/vbz.2021.0002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Although the urban areas of Abidjan, Côte d'Ivoire have faced recurrent outbreaks of Aedes-borne arboviruses, the seasonal dynamics of local populations of the key vector Aedes aegypti remained still underexplored for an effective vector control. The current study thus assessed the seasonal dynamics and the spatial distribution of Ae. aegypti in three neighborhoods of Abidjan city. Aedes eggs were collected using ovitraps in three different neighborhoods (Anoumambo, Bromakoté, and Petit-Bassam) during the four climatic seasons of Abidjan. Aedes egg samples were immersed into distilled water, and emerged larvae were reared until the adult stage for species morphological identification. Spatial autocorrelation was measured with the Moran's Index, and areas with high egg abundance were identified. In total, 3837 eggs were collected providing 1882 adult mosquitoes in the 3 neighborhoods. All the specimens belonged to only one Aedes species, Ae. aegypti. The average of 15.89 eggs per ovitrap, 13.67 eggs per ovitrap, and 19.87 eggs per ovitrap were obtained in Anoumambo, Bromakoté, and Petit-Bassam, respectively, with no statistical difference between the three sites. A higher abundance of Ae. aegypti was observed during the long rainy season and the short dry season. The Moran analysis showed a clustered distribution of Ae. aegypti eggs during the long rainy season in the three sites and a random spatial distribution during the short dry season. Ovitraps with high number of eggs were aggregated in the peripheral part (near to the lagoon) of Anoumambo and Petit-Bassam in central Bromakoté and extending along the railway during the long rainy season. This study revealed a heterogeneous potential risk of transmission of arbovirus according to neighborhood. It provided data to better understand Ae. aegypti ecology to select appropriate periods and places for Aedes vector control actions and surveillance of arboviruses in Abidjan.
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Affiliation(s)
- Mintokapieu Didier Stéphane Kpan
- Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Akré Maurice Adja
- Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Négnorogo Guindo-Coulibaly
- Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Konan Fabrice Assouho
- Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Affoué Mireille Nadia Kouadio
- Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Konan Rodolphe Mardoché Azongnibo
- Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire.,Institut de Géographie Tropicale (IGT), Université Félix Houphouët-Boigny (UFHB), Abidjan, Côte d'Ivoire
| | - Dounin Danielle Zoh
- Unité de Formation et de Recherches Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire
| | - Bi Zahouli Julien Zahouli
- Centre d'Entomologie Médicale et Vétérinaire, Université Alassane Ouattara, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire
| | - Franck Remoue
- Institut Pierre Richet/Institut National de Santé Publique (IPR/INSP), Bouaké, Côte d'Ivoire.,MIVEGEC (University of Montpellier, IRD, CNRS), Montpellier, France
| | - Florence Fournet
- Centre d'Entomologie Médicale et Vétérinaire, Université Alassane Ouattara, Abidjan, Côte d'Ivoire.,MIVEGEC (University of Montpellier, IRD, CNRS), Montpellier, France
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Traoré DF, Sagna AB, Assi SB, Tchiekoi BN, Adja AM, Dagnogo M, Koffi AA, Rogier C, Remoue F. Operational Evaluation of the Effectiveness of Long-lasting Insecticidal Nets on Human-Vector Contact in an African Urban Malaria Context. Open Forum Infect Dis 2020; 8:ofaa635. [PMID: 33553475 PMCID: PMC7850104 DOI: 10.1093/ofid/ofaa635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 12/28/2020] [Indexed: 11/30/2022] Open
Abstract
Background Malaria is still a major public health concern in Côte d’Ivoire despite mass distribution of long-lasting insecticidal nets (LLINs) as a key preventive strategy. This study intended to evaluate the operational effectiveness of LLINs on the level of human-vector contact using 1 antibody-based biomarker of exposure to Anopheles in urban areas. Methods This cross-sectional study collected socio-demographic data and use of LLINs from 9 neighborhoods in the city of Bouaké (Côte d’Ivoire). Dry blood spots performed in children aged >6 months and adults were used to evaluate immunoglobulin G (IgG) responses to the Anopheles gSG6-P1 salivary peptide. Results IgG response levels to the salivary peptide were significantly lower in individuals who declared having “always” (n = 270) slept under an LLIN compared with those who had “often” (n = 2087) and “never” (n = 88) slept under an LLIN (P < .0001). IgG response levels to gSG6-P1 between those who declared having “always” and “not always” slept under an LLIN varied according to neighborhood, socio-professional category, and age group. Conclusions The human IgG level to this gSG6-P1 salivary peptide could be a useful tool to evaluate the actual effectiveness of LLINs and help design behavioral change interventions that are crucial for sustaining universal coverage.
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Affiliation(s)
- Dipomin F Traoré
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,MIVEGEC, University of Montpellier, IRD, CNRS, Montpellier, France.,Unité de Formation et de Recherche en Sciences de la Nature (UFR SN), Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| | - André B Sagna
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,MIVEGEC, University of Montpellier, IRD, CNRS, Montpellier, France
| | - Serge B Assi
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Bertin N'Cho Tchiekoi
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Akré M Adja
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,Unité de Formation et de Recherche en Biosciences (UFR Biosciences), Université Félix Houphouët Boigny, Abidjan, Côte d'Ivoire
| | - Mamadou Dagnogo
- Unité de Formation et de Recherche en Sciences de la Nature (UFR SN), Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| | - Alphonsine A Koffi
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | | | - Franck Remoue
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,MIVEGEC, University of Montpellier, IRD, CNRS, Montpellier, France
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Arnal A, Roche B, Gouagna LC, Dujon A, Ujvari B, Corbel V, Remoue F, Poinsignon A, Pompon J, Giraudeau M, Simard F, Missé D, Lefèvre T, Thomas F. Cancer and mosquitoes - An unsuspected close connection. Sci Total Environ 2020; 743:140631. [PMID: 32758822 DOI: 10.1016/j.scitotenv.2020.140631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/28/2020] [Accepted: 06/28/2020] [Indexed: 06/11/2023]
Abstract
Cancer is a major public health issue and represents a significant burden in countries with different levels of economic wealth. In parallel, mosquito-borne infectious diseases represent a growing problem causing significant morbidity and mortality worldwide. Acknowledging that these two concerns are both globally distributed, it is essential to investigate whether they have a reciprocal connection that can fuel their respective burdens. Unfortunately, very few studies have examined the link between these two threats. This review provides an overview of the possible links between mosquitoes, mosquito-borne infectious diseases and cancer. We first focus on the impact of mosquitoes on carcinogenesis in humans including the transmission of oncogenic pathogens through mosquitoes, the immune reactions following mosquito bites, the presence of non-oncogenic mosquito-borne pathogens, and the direct transmission of cancer cells. The second part of this review deals with the direct or indirect consequences of cancer in humans on mosquito behaviour. Thirdly, we discuss the potential impacts that natural cancers in mosquitoes can have on their life history traits and therefore on their vector capacity. Finally, we discuss the most promising research avenues on this topic and the integrative public health strategies that could be envisioned in this context.
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Affiliation(s)
- Audrey Arnal
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France.
| | - Benjamin Roche
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France; Centre for Ecological and Evolutionary Research on Cancer (CREEC), Montpellier, France; IRD, Sorbonne Université, UMMISCO, F-93143 Bondy, France; Departamento de Etología, Fauna Silvestre y Animales de Laboratorio, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, Mexico; Centre de Recherche en Écologie et Évolution de la Santé (CREES), Montpellier, France
| | | | - Antoine Dujon
- Centre for Ecological and Evolutionary Research on Cancer (CREEC), Montpellier, France; School of Life and Environmental Sciences, Centre for Integrative Ecology, Deakin University, Waurn Ponds, VIC, Australia
| | - Beata Ujvari
- School of Life and Environmental Sciences, Centre for Integrative Ecology, Deakin University, Waurn Ponds, VIC, Australia
| | - Vincent Corbel
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France
| | - Franck Remoue
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France
| | | | - Julien Pompon
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France
| | - Mathieu Giraudeau
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France; Centre for Ecological and Evolutionary Research on Cancer (CREEC), Montpellier, France; Centre de Recherche en Écologie et Évolution de la Santé (CREES), Montpellier, France
| | - Frédéric Simard
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France; Centre de Recherche en Écologie et Évolution de la Santé (CREES), Montpellier, France
| | - Dorothée Missé
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France; Centre for Ecological and Evolutionary Research on Cancer (CREEC), Montpellier, France
| | - Thierry Lefèvre
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France; Centre de Recherche en Écologie et Évolution de la Santé (CREES), Montpellier, France; Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Frédéric Thomas
- MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France; Centre for Ecological and Evolutionary Research on Cancer (CREEC), Montpellier, France; Centre de Recherche en Écologie et Évolution de la Santé (CREES), Montpellier, France
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Sagna AB, Kassié D, Couvray A, Adja AM, Hermann E, Riveau G, Salem G, Fournet F, Remoue F. Spatial Assessment of Contact Between Humans and Anopheles and Aedes Mosquitoes in a Medium-Sized African Urban Setting, Using Salivary Antibody-Based Biomarkers. J Infect Dis 2020; 220:1199-1208. [PMID: 31152664 DOI: 10.1093/infdis/jiz289] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 05/30/2019] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Anarchic and poorly controlled urbanization led to an increased risk of mosquito-borne diseases (MBD) in many African cities. Here, we evaluate the spatial heterogeneity of human exposure to malaria and arboviral disease vectors in an urban area of northern Senegal, using antibody-based biomarkers of exposure to Anopheles and Aedes mosquito bites. METHODS A cross-sectional study was undertaken during the rainy season of 2014 in 4 neighborhoods of Saint-Louis, a city in northern Senegal. Among children aged 6-59 months in each neighborhood, the dried blood spot technique was used to evaluate immunoglobulin G (IgG) responses to both gSG6-P1 (Anopheles) and Nterm-34-kDa (Aedes) salivary peptides as validated biomarkers of respective mosquito bite exposure. RESULTS IgG response levels to gSG6-P1 and Nterm-34-kDa salivary peptides varied significantly between the 4 neighborhoods (P < .0001). The level of exposure to Aedes bites also varied according to household access to sanitation services (P = .027), whereas that of exposure to Anopheles bites varied according to insecticide-treated bed net use (P = .006). In addition, spatial clusters of high contact between humans and mosquitoes were identified inside 3 neighborhoods. CONCLUSIONS Antibody-based biomarkers of exposure to Anopheles and Aedes mosquito bites could be helpful tools for evaluating the heterogeneity of exposure to malaria and arboviral disease vectors by national control programs.
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Affiliation(s)
- André B Sagna
- MIVEGEC, University of Montpellier, CNRS, IRD
- Institut Pierre Richet/Institut National de Santé Publique, Bouaké, Côte d'Ivoire
- Biomedical Research Center Espoir Pour La Santé, Saint-Louis, Sénégal
| | - Daouda Kassié
- ASTRE, University of Montpellier, CIRAD, INRA, Montpellier
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | | | - Akré Maurice Adja
- Institut Pierre Richet/Institut National de Santé Publique, Bouaké, Côte d'Ivoire
| | - Emmanuel Hermann
- CIIL, Institut Pasteur de Lille, University of Lille, CNRS UMR, Inserm, Lille, France
| | - Gilles Riveau
- CIIL, Institut Pasteur de Lille, University of Lille, CNRS UMR, Inserm, Lille, France
- Biomedical Research Center Espoir Pour La Santé, Saint-Louis, Sénégal
| | - Gérard Salem
- CEPED, University of Paris Descartes, IRD, Paris
| | - Florence Fournet
- MIVEGEC, University of Montpellier, CNRS, IRD
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
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8
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Aka KG, Traoré DF, Sagna AB, Zoh DD, Assi SB, Tchiekoi BN, Adja AM, Remoue F, Poinsignon A. Pattern of antibody responses to Plasmodium falciparum antigens in individuals differentially exposed to Anopheles bites. Malar J 2020; 19:83. [PMID: 32085710 PMCID: PMC7033907 DOI: 10.1186/s12936-020-03160-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 02/12/2020] [Indexed: 11/16/2022] Open
Abstract
Background In malaria-endemic areas, human populations are frequently exposed to immunomodulatory salivary components injected during mosquito blood feeding. The consequences on pathogen-specific immune responses are not well known. This study evaluated and compared the humoral responses specific to merozoite stage vaccine candidates of Plasmodium falciparum, in children differentially exposed to Anopheles bites in a natural setting. Methods The cross-sectional study was carried out in Bouaké (Côte d’Ivoire) where entomological data and blood samples from children (0–14 years) were collected in two sites with similar malaria prevalence. Antibody (IgG, IgG1, IgG3) responses to PfAMA1 and PfMSP1 were evaluated by ELISA. Univariate and multivariate analysis were performed to assess the relationship between the immune responses to P. falciparum antigens and exposure to Anopheles bites in the total cohort and in each site, separately. The individual level of exposure to Anopheles bites was evaluated by quantifying specific IgG response to the Anopheles gSG6-P1 salivary peptide, which represents a proxy of Anopheles exposure. Results The anti-Plasmodium humoral responses were different according to the level of exposure of children, with those highly exposed to Anopheles presenting significantly lower antibody responses to PfMSP1 in total population (IgG and IgG3) and in Petessou village (IgG, IgG1, IgG3). No significant difference was seen for PfAMA1 antigen between children differently exposed to Anopheles. In Dar-es-Salam, a neighbourhood where a high Culex density was reported, children presented very low antibody levels specific to both antigens, and no difference according to the exposure to Anopheles bites was found. Conclusion These findings may suggest that immunomodulatory components of Anopheles saliva, in addition to other factors, may participate to the modulation of the humoral response specific to Plasmodium merozoite stage antigens. This epidemiological observation may form a starting point for additional work to decipher the role of mosquito saliva on the modulation of the anti-Plasmodium acquired immunity and clinical protection in combining both field and ex vivo immunological studies.
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Affiliation(s)
- Kakou G Aka
- Institut Pierre Richet, Institut National de Santé Publique, Bouaké, Côte d'Ivoire. .,MIVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France.
| | - Dipomin F Traoré
- Institut Pierre Richet, Institut National de Santé Publique, Bouaké, Côte d'Ivoire.,MIVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France.,UFR Sciences de la Nature, Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| | - André B Sagna
- Institut Pierre Richet, Institut National de Santé Publique, Bouaké, Côte d'Ivoire.,MIVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France
| | - Dounin D Zoh
- Institut Pierre Richet, Institut National de Santé Publique, Bouaké, Côte d'Ivoire.,UFR Biosciences, Université Félix Houphouët Boigny, Abidjan, Côte d'Ivoire
| | - Serge B Assi
- Institut Pierre Richet, Institut National de Santé Publique, Bouaké, Côte d'Ivoire
| | | | - Akré M Adja
- Institut Pierre Richet, Institut National de Santé Publique, Bouaké, Côte d'Ivoire.,UFR Biosciences, Université Félix Houphouët Boigny, Abidjan, Côte d'Ivoire
| | - Franck Remoue
- Institut Pierre Richet, Institut National de Santé Publique, Bouaké, Côte d'Ivoire.,MIVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France
| | - Anne Poinsignon
- Institut Pierre Richet, Institut National de Santé Publique, Bouaké, Côte d'Ivoire.,MIVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France
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9
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Sadia-Kacou CAM, Yobo CM, Adja MA, Sagna AB, Ndille EE, Poinsignon A, Tano Y, Koudou BG, Remoue F. Use of Anopheles salivary biomarker to assess seasonal variation of human exposure to Anopheles bites in children living near rubber and oil palm cultivations in Côte d'Ivoire. Parasite Epidemiol Control 2019; 5:e00102. [PMID: 30923754 PMCID: PMC6423992 DOI: 10.1016/j.parepi.2019.e00102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/06/2019] [Accepted: 03/06/2019] [Indexed: 10/31/2022] Open
Abstract
Environmental changes related to agricultural practices and activities can impact malaria transmission. In the objective to evaluate this impact on the human-vector contact, the level of human exposure to Anopheles vector bites was assess by an immuno-epidemiological indicator based on the assessment of the human IgG antibody response to the Anopheles gambiae gSG6-P1 salivary peptide, previously validated as a pertinent biomarker. Two cross-sectional surveys were carried out in the dry and rainy season in three villages with intensive agricultural plantations (N'Zikro with rubber cultivation, Ehania-V5 and Ehania-V1 with palm oil exploitation) and in a control village without plantations (Ayébo). Overall, 775 blood samples were collected in filter papers from children aged 1 to 14 years-old for immunological analysis by ELISA. The IgG levels to the gSG6-P1 salivary peptide significantly differed between studied villages both in the dry and the rainy seasons (P < 0.0001) and were higher in agricultural villages compared to the control area. In particular, the level of specific IgG in Ehania-V5, located in the heart of palm oil plantations, was higher compared to other agricultural villages. Interestingly, the level of specific IgG levels classically increased between the dry and the rainy season in the control village (P < 0.0001) whereas it remained high in the dry season as observed in the rainy season in agricultural villages. The present study indicated that rubber and oil palm plantations could maintain a high level of human exposure to Anopheles bites during both the dry and rainy seasons. These agricultural activities could therefore represent a permanent factor of malaria transmission risk.
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Affiliation(s)
- Cécile Agnimou Malanfoua Sadia-Kacou
- Institut Pierre Richet (IPR), Institut National de Santé Publique (INSP), 01 BP 1500, Bouaké 01, Côte d'Ivoire.,UFR Biosciences, Université Félix Houphouët Boigny, 08 3800, Abidjan 08, Côte d'Ivoire
| | - Céline Mabot Yobo
- Institut Pierre Richet (IPR), Institut National de Santé Publique (INSP), 01 BP 1500, Bouaké 01, Côte d'Ivoire.,UFR Science de la Nature, Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| | - Maurice Akré Adja
- Institut Pierre Richet (IPR), Institut National de Santé Publique (INSP), 01 BP 1500, Bouaké 01, Côte d'Ivoire.,UFR Biosciences, Université Félix Houphouët Boigny, 08 3800, Abidjan 08, Côte d'Ivoire
| | - André Barembaye Sagna
- Institut Pierre Richet (IPR), Institut National de Santé Publique (INSP), 01 BP 1500, Bouaké 01, Côte d'Ivoire.,MIVEGEC (University of Montpellier, CNRS, IRD): Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle, Montpellier, France
| | - Emmanuel Elanga Ndille
- MIVEGEC (University of Montpellier, CNRS, IRD): Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle, Montpellier, France
| | - Anne Poinsignon
- Institut Pierre Richet (IPR), Institut National de Santé Publique (INSP), 01 BP 1500, Bouaké 01, Côte d'Ivoire.,MIVEGEC (University of Montpellier, CNRS, IRD): Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle, Montpellier, France
| | - Yao Tano
- UFR Biosciences, Université Félix Houphouët Boigny, 08 3800, Abidjan 08, Côte d'Ivoire.,UFR Science de la Nature, Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| | - Benjamin Guibehi Koudou
- UFR Science de la Nature, Université Nangui Abrogoua, Abidjan, Côte d'Ivoire.,Filariasis Programme Support Unit from Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre Suisse de Recherches Scientifiques (CSRS), Abidjan, Côte d'Ivoire
| | - Franck Remoue
- Institut Pierre Richet (IPR), Institut National de Santé Publique (INSP), 01 BP 1500, Bouaké 01, Côte d'Ivoire.,MIVEGEC (University of Montpellier, CNRS, IRD): Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle, Montpellier, France
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10
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Traoré DF, Sagna AB, Adja AM, Zoh DD, Adou KA, Lingué KN, Coulibaly I, Tchiekoi NB, Assi SB, Poinsignon A, Dagnogo M, Remoue F. Exploring the heterogeneity of human exposure to malaria vectors in an urban setting, Bouaké, Côte d'Ivoire, using an immuno-epidemiological biomarker. Malar J 2019; 18:68. [PMID: 30857543 PMCID: PMC6413440 DOI: 10.1186/s12936-019-2696-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 03/01/2019] [Indexed: 11/24/2022] Open
Abstract
Background In some African cities, urban malaria is a threat to the health and welfare of city dwellers. To improve the control of the disease, it is critical to identify neighbourhoods where the risk of malaria transmission is the highest. This study aims to evaluate the heterogeneity of malaria transmission risk in one city (Bouaké) in a West African country (Côte d’Ivoire) that presents several levels of urbanization. Methods Two cross-sectional studies were conducted in three neighbourhoods (Dar-es-Salam, Kennedy and N’gattakro) in Bouaké during both the rainy and dry seasons. Data on insecticide-treated net (ITN) use and blood samples were collected from children aged between 6 months and 15 years to determine the parasite density and the prevalence of Plasmodium falciparum and the level of IgG against the Anopheles gSG6-P1 salivary peptide, used as the biomarker of Anopheles bite exposure. Results The specific IgG levels to the gSG6-P1 salivary peptide in the rainy season were significantly higher compared to the dry season in all neighbourhoods studied (all p < 0.001). Interestingly, these specific IgG levels did not differ between neighbourhoods during the rainy season, whereas significant differences in IgG level were observed in the dry season (p = 0.034). ITN use could be a major factor of variation in the specific IgG level. Nevertheless, no difference in specific IgG levels to the gSG6-P1 salivary peptide was observed between children who declared “always” versus “never” sleeping under an ITN in each neighbourhood. In addition, the prevalence of P. falciparum in the whole population and immune responders was significantly different between neighbourhoods in each season (p < 0.0001). Conclusion This study highlights the high risk of malaria exposure in African urban settings and the high heterogeneity of child exposure to the Anopheles vector between neighbourhoods in the same city. The Anopheles gSG6-P1 salivary peptide could be a suitable biomarker to accurately and quantitatively assess the risk of malaria transmission in urban areas. Electronic supplementary material The online version of this article (10.1186/s12936-019-2696-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dipomin F Traoré
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire. .,MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France. .,Unité de Formation et de Recherche en Sciences de la nature (UFR SN), Université Nangui Abrogoua, Abidjan, Côte d'Ivoire.
| | - André B Sagna
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France
| | - Akré M Adja
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,Unité de Formation et de Recherche en Biosciences (UFR Biosciences), Université Félix Houphouët Boigny, Abidjan, Côte d'Ivoire
| | - Dounin D Zoh
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,Unité de Formation et de Recherche en Biosciences (UFR Biosciences), Université Félix Houphouët Boigny, Abidjan, Côte d'Ivoire
| | - Kouassi A Adou
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,Institut de Géographie Tropicale (IGT), Université Félix Houphouët Boigny, Abidjan, Côte d'Ivoire
| | - Kouassi N Lingué
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Issa Coulibaly
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - N'Cho Bertin Tchiekoi
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Serge B Assi
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Anne Poinsignon
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France
| | - Mamadou Dagnogo
- Unité de Formation et de Recherche en Sciences de la nature (UFR SN), Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
| | - Franck Remoue
- Institut Pierre Richet (IPR), Institut National de la Santé Publique (INSP), Bouaké, Côte d'Ivoire.,MIVEGEC, Univ. Montpellier, CNRS, IRD, Montpellier, France
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11
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Toure OA, Landry TN, Assi SB, Kone AA, Gbessi EA, Ako BA, Coulibaly B, Kone B, Ouattara O, Beourou S, Koffi A, Remoue F, Rogier C. Malaria parasite clearance from patients following artemisinin-based combination therapy in Côte d'Ivoire. Infect Drug Resist 2018; 11:2031-2038. [PMID: 30464545 PMCID: PMC6208791 DOI: 10.2147/idr.s167518] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Introduction Parasite clearance is useful to detect artemisinin resistance. The aim of this study was to investigate parasite clearance in patients treated with artesunate + amodiaquine (AS + AQ) and artemether + lumefantrine (AL): the two artemisinin-based combination therapies (ACTs) recommended in the first-line treatment of uncomplicated malaria in Côte d’Ivoire. Methods This study was conducted in Bouaké, Côte d’Ivoire, from April to June 2016. Patients aged at least 6 months with uncomplicated malaria and treated with AS + AQ or AL were hospitalized for 3 days, and follow-up assessments were performed on days 3, 7, 14, 21, 28, 35, and 42. Blood smears were collected at the time of screening, pre-dose, and 6-hour intervals following the first dose of administration until two consecutive negative smears were recorded, thereafter at day 3 and follow-up visits. Parasite clearance was determined using the Worldwide Antimalarial Resistance Network’s parasite clearance estimator. The primary end points were parasite clearance rate and time. Results A total of 120 patients (57 in the AS + AQ group and 63 in the AL group) were randomized among 298 patients screened. The median parasite clearance time was 30 hours (IQR, 24–36 hours), for each ACT. The median parasite clearance rate had a slope half-life of 2.36 hours (IQR, 1.85–2.88 hours) and 2.23 hours (IQR, 1.74–2.63 hours) for AS + AQ and AL, respectively. The polymerase chain reaction-corrected adequate clinical and parasitological response was 100% and 98.07% at day 42 for AS + AQ and AL, respectively. Conclusion Patients treated with AS + AQ and AL had cleared parasites rapidly. ACTs are still efficacious in Bouaké, Côte d’Ivoire, but continued efficacy monitoring of ACTs is needed.
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Affiliation(s)
| | | | - Serge Brice Assi
- Malaria and Anopheles Research and Management Unit, Pierre Richet Institute, Bouake, Côte d'Ivoire.,National Malaria Control Program, Bouake, Côte d'Ivoire
| | | | - Eric Adji Gbessi
- Malariology Unit, Pasteur Institute of Côte d'Ivoire, Abidjan, Côte d'Ivoire,
| | | | - Baba Coulibaly
- Malariology Unit, Pasteur Institute of Côte d'Ivoire, Abidjan, Côte d'Ivoire,
| | - Bouakary Kone
- Department of Medicine, Health Care Center of Dar-Es-Salam, Bouake, Côte d'Ivoire
| | - Oumar Ouattara
- Department of Medicine, Health Care Center of Dar-Es-Salam, Bouake, Côte d'Ivoire
| | - Sylvain Beourou
- Malariology Unit, Pasteur Institute of Côte d'Ivoire, Abidjan, Côte d'Ivoire,
| | - Alphonsine Koffi
- Malaria and Anopheles Research and Management Unit, Pierre Richet Institute, Bouake, Côte d'Ivoire
| | - Franck Remoue
- Malaria and Anopheles Research and Management Unit, Pierre Richet Institute, Bouake, Côte d'Ivoire.,UMR 224-MIVEGEC, Research Development Institute, Montpellier, France
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12
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Sagna AB, Yobo MC, Elanga Ndille E, Remoue F. New Immuno-Epidemiological Biomarker of Human Exposure to Aedes Vector Bites: From Concept to Applications. Trop Med Infect Dis 2018; 3:E80. [PMID: 30274476 PMCID: PMC6161005 DOI: 10.3390/tropicalmed3030080] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 07/23/2018] [Accepted: 07/30/2018] [Indexed: 12/13/2022] Open
Abstract
Arthropod-borne viruses (arboviruses) such as dengue virus (DENV), chikungunya virus (CHIKV), Zika virus (ZIKV), and yellow fever virus (YFV) are the most important 'emerging pathogens' because of their geographic spread and their increasing impact on vulnerable human populations. To fight against these arboviruses, vector control strategies (VCS) remain one of the most valuable means. However, their implementation and monitoring are labour intensive and difficult to sustain on large scales, especially when transmission and Aedes mosquito densities are low. To increase the efficacy of VCS, current entomological methods should be improved by new complementary tools which measure the risk of arthropod-borne diseases' transmission. The study of human⁻Aedes immunological relationships can provide new promising serological tools, namely antibody-based biomarkers, allowing to accurately estimate the human⁻Aedes contact and consequently, the risk of transmission of arboviruses and the effectiveness of VCS. This review focuses on studies highlighting the concept, techniques, and methods used to develop and validate specific candidate biomarkers of human exposure to Aedes bites. Potential applications of such antibody-based biomarkers of exposure to Aedes vector bites in the field of operational research are also discussed.
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Affiliation(s)
- André B Sagna
- MIVEGEC, IRD, CNRS, Univ. Montpellier, BP 64501, 34394 Montpellier, France.
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), BP 1500 Bouaké, Côte d'Ivoire.
| | - Mabo C Yobo
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), BP 1500 Bouaké, Côte d'Ivoire
- UFR Sciences de la Nature, Université Nangui Abrogoua, Abidjan, Côte d'Ivoire, BP 801 Abidjan, Côte d'Ivoire
| | - Emmanuel Elanga Ndille
- MIVEGEC, IRD, CNRS, Univ. Montpellier, BP 64501, 34394 Montpellier, France.
- Department of Medical Entomology, Centre for Research in Infectious Diseases (CRID), P.O. Box 13591, Yaoundé, Cameroun.
| | - Franck Remoue
- MIVEGEC, IRD, CNRS, Univ. Montpellier, BP 64501, 34394 Montpellier, France.
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13
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Traoré DF, Sagna AB, Adja AM, Zoh DD, Lingué KN, Coulibaly I, N’Cho Tchiekoi B, Assi SB, Poinsignon A, Dagnogo M, Remoue F. Evaluation of Malaria Urban Risk Using an Immuno-Epidemiological Biomarker of Human Exposure to Anopheles Bites. Am J Trop Med Hyg 2018; 98:1353-1359. [PMID: 29512479 PMCID: PMC5953354 DOI: 10.4269/ajtmh.17-0231] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 11/22/2017] [Indexed: 11/07/2022] Open
Abstract
Urban malaria is an underestimated serious health concern in African countries. This study aimed to evaluate the risk of malaria transmission in an urban area by evaluating the level of human exposure to Anopheles bites using an Anopheles salivary biomarker (gambiae Salivary Gland Protein-6 peptide 1 [gSG6-P1] peptide). Two multidisciplinary cross-sectional studies were undertaken in five sites of Bouaké city (three urban districts and two surrounding villages, used as control; Côte d'Ivoire) during the rainy season and the dry season. Blood samples were obtained from children 6 months to 14 years of age for immunological tests. The level of anti-gSG6-P1 immunoglobulin G (IgG) antibodies was significantly higher in the rainy season than the dry season in both urban and rural sites (P < 0.0001). Interestingly, children with the highest anti-gSG6-P1 IgG responses in the rainy season were infected by Plasmodium falciparum. Surprisingly, no difference of anti-gSG6-P1 IgG level was observed between urban and rural areas, for either season. The current data suggest that children in the urban city of Bouaké could be as highly exposed to Anopheles bites as children living in surrounding villages. The immunological biomarker of human exposure to Anopheles bites may be used to accurately assess the potential risk of malaria transmission in African urban settings.
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Affiliation(s)
- Dipomin F. Traoré
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR IRD.224-CNRS.5290, Université de Montpellier, Montpellier, France
- Unité de Formation et de Recherche des Sciences de la nature (UFR SN) Université Nangui Abrogoua, Abidjan, Côte d’Ivoire
| | - André B. Sagna
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR IRD.224-CNRS.5290, Université de Montpellier, Montpellier, France
| | - Akré M. Adja
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
- Unité de Formation et de Recherche Biosciences (UFR Biosciences), Université Félix Houphouët Boigny, Abidjan, Côte d’Ivoire
| | - Dounin D. Zoh
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
- Unité de Formation et de Recherche Biosciences (UFR Biosciences), Université Félix Houphouët Boigny, Abidjan, Côte d’Ivoire
| | - Kouassi N. Lingué
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
| | - Issa Coulibaly
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
| | - Bertin N’Cho Tchiekoi
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
| | - Serge B. Assi
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
| | - Anne Poinsignon
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR IRD.224-CNRS.5290, Université de Montpellier, Montpellier, France
| | - Mamadou Dagnogo
- Unité de Formation et de Recherche des Sciences de la nature (UFR SN) Université Nangui Abrogoua, Abidjan, Côte d’Ivoire
| | - Franck Remoue
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d’Ivoire
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR IRD.224-CNRS.5290, Université de Montpellier, Montpellier, France
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14
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Damien BG, Aguemon B, Abdoulaye Alfa D, Bocossa D, Ogouyemi-Hounto A, Remoue F, Le Hesran JY. Low use of artemisinin-based combination therapy for febrile children under five and barriers to correct fever management in Benin: a decade after WHO recommendation. BMC Public Health 2018; 18:168. [PMID: 29357869 PMCID: PMC5778640 DOI: 10.1186/s12889-018-5077-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 01/12/2018] [Indexed: 11/16/2022] Open
Abstract
Background Artemisinin-based combination therapy (ACT), used to treat uncomplicated malaria cases, is one of the main strategies of malaria control and elimination. One of the main objectives of the Benin National Malaria Control Program’s (NMCP) strategic plan is to ensure that at least 80% of uncomplicated malaria is treated with ACT within 24 h. Therefore, it was of great interest to measure whether the country case management of fever amongst children under five, adhered to the NMCP’s strategic plan and look into the barriers to the use of ACT. Methods A cross-sectional survey based on a cluster and multi-stage sampling was conducted in two rural health districts in Benin. We recruited 768 and 594 children under five years were included in the northern and in the southern respectively. Data was collected on the general use of ACT and on the correct use of ACT that adheres to the NMCP’s strategy, as well as the barriers that prevent the proper management of fever amongst children. To assess the certain predictors of ACT usage, logistic regression was used, while taking into account the cluster random effect. Results Among febrile children aged 6 to 59 months, 20.7% in the south and 33.9% in north received ACT. The correct use of ACT, was very low, 5.8% and in southern and 8.6% northern areas. Caregivers who received information on ACT were 3.13 time more likely in the south and 2.98 time more likely in the north to give ACT to their feverish child, PPR = 3.13[1.72–4.15] and PPR = 2.98 [2.72–3.11] respectively. Chloroquine and quinine, other malaria treatments not recommended by NMCP, were still being used in both areas: 12.3 and 3.3% in the south and 11.4 and 3.0% in the north. Conclusion In Benin, the use and the correct use of ACT for febrile children remains low. The study also showed that having received information about the use of ACT is positively associated with the use of ACT. This point highlights the fact that efforts may not have been sufficiently integrated with social communication, which should be based on the behavioural determinants of populations. Electronic supplementary material The online version of this article (10.1186/s12889-018-5077-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- B G Damien
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR IRD 224-CNRS 5290, University of Montpellier, Montpellier, France. .,Centre de Recherche Entomologique de Cotonou, Bénin / Institut de Recherche pour le Développement, UMR 224-CNRS 5290 MIVEGEC, Cotonou, Bénin. .,Département de Santé Publique, Faculté des Sciences de la Santé de Cotonou, Université d'Abomey-Calavi, Cotonou, Bénin.
| | - B Aguemon
- Département de Santé Publique, Faculté des Sciences de la Santé de Cotonou, Université d'Abomey-Calavi, Cotonou, Bénin
| | - D Abdoulaye Alfa
- Centre de Recherche Entomologique de Cotonou, Bénin / Institut de Recherche pour le Développement, UMR 224-CNRS 5290 MIVEGEC, Cotonou, Bénin
| | - D Bocossa
- Université Paris 8, UFR Etudes - Recherche - et Ingénierie en territoires - Environnements - Société, Saint-Denis, France
| | - A Ogouyemi-Hounto
- Unité d'Enseignement et de Recherche en Parasitologie Mycologie/Faculté des Sciences de la Santé, Laboratoire du Centre de Lutte Intégrée contre le Paludisme, Université d'Abomey-Calavi, Cotonou, Bénin
| | - F Remoue
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR IRD 224-CNRS 5290, University of Montpellier, Montpellier, France.,Centre de Recherche Entomologique de Cotonou, Bénin / Institut de Recherche pour le Développement, UMR 224-CNRS 5290 MIVEGEC, Cotonou, Bénin
| | - J-Y Le Hesran
- Institut de Recherche pour le Développement (IRD) / Mère et enfant face aux infections tropicales (MERIT), UMR 216, Cotonou, Bénin
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15
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Ya-Umphan P, Cerqueira D, Parker DM, Cottrell G, Poinsignon A, Remoue F, Brengues C, Chareonviriyaphap T, Nosten F, Corbel V. Use of an Anopheles Salivary Biomarker to Assess Malaria Transmission Risk Along the Thailand-Myanmar Border. J Infect Dis 2017; 215:396-404. [PMID: 27932615 PMCID: PMC5853934 DOI: 10.1093/infdis/jiw543] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 11/15/2016] [Indexed: 11/13/2022] Open
Abstract
Background The modalities of malaria transmission along the Thailand-Myanmar border are poorly understood. Here we address the relevance of using a specific Anopheles salivary biomarker to measure the risk among humans of exposure to Anopheles bites. Methods Serologic surveys were conducted from May 2013 to December 2014 in 4 sentinel villages. More than 9400 blood specimens were collected in filter papers from all inhabitants at baseline and then every 3 months thereafter, for up to 18 months, for analysis by enzyme-linked immunosorbent assay. The relationship between the intensity of the human antibody response and entomological indicators of transmission (human biting rates and entomological inoculation rates [EIRs]) was studied using a multivariate 3-level mixed model analysis. Heat maps for human immunoglobulin G (IgG) responses for each village and survey time point were created using QGIS 2.4. Results The levels of IgG response among participants varied significantly according to village, season, and age (P<.001) and were positively associated with the abundance of total Anopheles species and primary malaria vectors and the EIR (P<.001). Spatial clusters of high-IgG responders were identified across space and time within study villages. Conclusions The gSG6-P1 biomarker has great potential to address the risk of transmission along the Thailand-Myanmar border and represents a promising tool to guide malaria interventions.
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Affiliation(s)
- Phubeth Ya-Umphan
- Institut de Recherche pour le Développement, Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle, Montpellier, and
- Department of Entomology, Faculty of Agriculture, and
| | - Dominique Cerqueira
- Department of Entomology, Faculty of Agriculture, and
- Shoklo Malaria Research Unit, Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand; and
| | - Daniel M Parker
- Shoklo Malaria Research Unit, Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand; and
| | - Gilles Cottrell
- Institut de Recherche pour le Développement, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Anne Poinsignon
- Institut de Recherche pour le Développement, Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle, Montpellier, and
| | - Franck Remoue
- Institut de Recherche pour le Développement, Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle, Montpellier, and
| | - Cecile Brengues
- Institut de Recherche pour le Développement, Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle, Montpellier, and
| | - Theeraphap Chareonviriyaphap
- Department of Entomology, Faculty of Agriculture, and
- Center for Advanced Studies for Agriculture and Food, Kasetsart University Institute for Advanced Studies, Kasetsart University, Bangkok, and
| | - Francois Nosten
- Shoklo Malaria Research Unit, Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand; and
- Nuffield Department of Medicine, Centre for Tropical Medicine, University of Oxford, United Kingdom
| | - Vincent Corbel
- Institut de Recherche pour le Développement, Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle, Montpellier, and
- Institut de Recherche pour le Développement, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
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16
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Elanga Ndille E, Doucoure S, Poinsignon A, Mouchet F, Cornelie S, D’Ortenzio E, DeHecq JS, Remoue F. Human IgG Antibody Response to Aedes Nterm-34kDa Salivary Peptide, an Epidemiological Tool to Assess Vector Control in Chikungunya and Dengue Transmission Area. PLoS Negl Trop Dis 2016; 10:e0005109. [PMID: 27906987 PMCID: PMC5131890 DOI: 10.1371/journal.pntd.0005109] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 10/14/2016] [Indexed: 11/18/2022] Open
Abstract
Background Arboviral diseases are an important public health concerns. Vector control remains the sole strategy to fight against these diseases. Because of the important limits of methods currently used to assess human exposure to Aedes mosquito bites, much effort is being devoted to develop new indicators. Recent studies have reported that human antibody (Ab) responses to Aedes aegypti Nterm-34kDa salivary peptide represent a promising biomarker tool to evaluate the human-Aedes contact. The present study aims investigate whether such biomarker could be used for assessing the efficacy of vector control against Aedes. Methodology/Principal findings Specific human IgG response to the Nterm-34kDa peptide was assessed from 102 individuals living in urban area of Saint-Denis at La Reunion Island, Indian Ocean, before and after the implementation of vector control against Aedes mosquitoes. IgG response decreased after 2 weeks (P < 0.0001), and remained low for 4 weeks post-intervention (P = 0.0002). The specific IgG decrease was associated with the decline of Aedes mosquito density, as estimated by entomological parameters and closely correlated to vector control implementation and was not associated with the use of individual protection, daily commuting outside of the house, sex and age. Our findings indicate a probable short-term decrease of human exposure to Aedes bites just after vector control implementation. Conclusion/Significance Results provided in the present study indicate that IgG Ab response to Aedes aegypti Nterm-34kDa salivary peptide could be a relevant short-time indicator for evaluating the efficacy of vector control interventions against Aedes species. In absence of effective treatment and vaccine, vector control is the main strategy against arboviral diseases such as dengue, Zika and chikungunya. Given the limitation of entomologic tool currently used, news tools are urgently needed to assess the efficacy of vector control against arboviral diseases. The present study aimed to investigate whether human IgG antibody specific response to only one Aedes salivary peptide could be useful for assessing the efficacy of vector control against arboviral diseases. For this purpose, IgG response to Nterm-34kDa peptide was assessed from 102 individuals living in urban area at La Reunion Island, Indian Ocean, before and after the implementation of vector control against Aedes albopictus mosquito species. A significant decrease of this specific IgG level was noticed after vector control implementation. The decrease was associated to the decline in Aedes mosquito density estimated by entomological parameters, such as adult mosquito density, House and Breteau indices. The results of the present study indicated that human IgG response to the Aedes Nterm-34kDa salivary peptide could be a useful tool to evaluate the efficacy of vector control strategies against arboviruses.
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Affiliation(s)
- Emmanuel Elanga Ndille
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, FRANCE
- * E-mail: (FR); (EEN); (SD); (AP); (FM); (SC); (EDO); (JSD)
| | - Souleymane Doucoure
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, FRANCE
- * E-mail: (FR); (EEN); (SD); (AP); (FM); (SC); (EDO); (JSD)
| | - Anne Poinsignon
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, FRANCE
- * E-mail: (FR); (EEN); (SD); (AP); (FM); (SC); (EDO); (JSD)
| | - François Mouchet
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, FRANCE
- * E-mail: (FR); (EEN); (SD); (AP); (FM); (SC); (EDO); (JSD)
| | - Sylvie Cornelie
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, FRANCE
- * E-mail: (FR); (EEN); (SD); (AP); (FM); (SC); (EDO); (JSD)
| | - Eric D’Ortenzio
- Institut de Veille Sanitaire, Cire Océan Indien, Saint-Denis, La Réunion
- * E-mail: (FR); (EEN); (SD); (AP); (FM); (SC); (EDO); (JSD)
| | - Jean Sébastien DeHecq
- Agence Régionale de Santé, Océan Indien, Saint Denis, La Réunion
- * E-mail: (FR); (EEN); (SD); (AP); (FM); (SC); (EDO); (JSD)
| | - Franck Remoue
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, FRANCE
- * E-mail: (FR); (EEN); (SD); (AP); (FM); (SC); (EDO); (JSD)
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17
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Noukpo MH, Damien GB, Elanga-N'Dille E, Sagna AB, Drame PM, Chaffa E, Boussari O, Corbel V, Akogbéto M, Remoue F. Operational Assessment of Long-Lasting Insecticidal Nets by Using an Anopheles Salivary Biomarker of Human-Vector Contact. Am J Trop Med Hyg 2016; 95:1376-1382. [PMID: 27928087 DOI: 10.4269/ajtmh.15-0541] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 08/19/2016] [Indexed: 01/10/2023] Open
Abstract
The widespread implementation of long-lasting insecticidal nets (LLINs) is a major intervention method for malaria control. Although the LLINs coverage increases, information available on the physical integrity (PI) of implemented LLINs is incomplete. This study aimed to validate human IgG antibody (Ab) response to Anopheles gSG6-P1 salivary peptide antigen, previously demonstrated as a pertinent biomarker of human exposure to Anopheles bites, for evaluating the PI of LLINs in field conditions. We analyzed data from 262 randomly selected children (< 5 years of age) in health districts of Benin. Anti-gSG6-P1 IgG responses were assessed and compared with the PI of LLINs that these same children slept under, and evaluated by the hole index (HI). Specific IgG levels were positively correlated to LLINs HI (r = 0.342; P < 0.0001). According to antipeptide IgG level (i.e., intensity of vector exposure), two categories of LLINs PI were defined: 1) group "HI: [0, 100]" corresponding to LLINs with "good" PI and 2) "HI > 100" corresponding to LLINs with "bad" PI. These results suggest that human Ab response to salivary peptide could be a complementary tool to help defining a standardized threshold of efficacy for LLINs under field use.
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Affiliation(s)
- Mahoutin H Noukpo
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.,UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - Georgia B Damien
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.,UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - Emmanuel Elanga-N'Dille
- UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - André B Sagna
- Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Papa M Drame
- UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - Evelyne Chaffa
- Programme National de Lutte Contre le Paludisme (PNLP), Ministère de la Santé, Cotonou, Bénin
| | - Olayidé Boussari
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.,UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin
| | - Vincent Corbel
- UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin.,Department of Entomology, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Nakhon Pathom, Thailand
| | - Martin Akogbéto
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.,Faculté des Sciences et Techniques (FAST), Université d'Abomey Calavi (UAC), Abomey, Bénin
| | - Franck Remoue
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin. .,UMR IRD 224-CNRS 5290-Universités Montpellier Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Cotonou, Bénin.,Institut Pierre Richet (IPR), Institut Nationale de la Santé Publique (INSP), Bouaké, Côte d'Ivoire
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18
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Ogouyèmi-Hounto A, Azandossessi C, Lawani S, Damien G, de Tove YSS, Remoue F, Kinde Gazard D. Therapeutic efficacy of artemether-lumefantrine for the treatment of uncomplicated falciparum malaria in northwest Benin. Malar J 2016; 15:37. [PMID: 26801767 PMCID: PMC4722724 DOI: 10.1186/s12936-016-1091-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/10/2016] [Indexed: 11/10/2022] Open
Abstract
Background Artemether/lumefantrine (Coartem®) has been used as a treatment for uncomplicated Plasmodium falciparum infection since 2004 in Benin. This open-label, non-randomized study evaluated efficacy of artemether–lumefantrine (AL) in treatment of uncomplicated falciparum malaria in children aged 6–59 months in two malaria transmission sites in northwest Benin. Methods
A 42-day therapeutic efficacy study was conducted between August and November 2014, in accordance with 2009 WHO guidelines. One-hundred and twenty-three children, aged 6 months to 5 years, with uncomplicated falciparum malaria were recruited into the study. The primary endpoint was parasitological cure on day 28 and day 42 while the secondary endpoints included: parasite and fever clearance, improvement in haemoglobin levels. Outcomes were classified as early treatment failure (ETF), late clinical failure, late parasitological failure, and adequate clinical and parasitological response (ACPR). Results Before PCR correction, ACPR rates were 87 % (95 % CI 76.0–94.7) and 75.6 %, respectively (95 % CI 67.0–82.9) on day 28 and day 42. In each study site, ACPR rates were 78.3 % in Djougou and 73 % in Cobly on day 42. There was no ETF and after PCR correction ACPR was 100 % in study population. All treatment failures were shown to be due to new infections. Fever was significantly cleared in 24 h and approximately 90 % of parasites where cleared on day 1 and almost all parasites were cleared on day 2. Haemoglobin concentration showed a slight increase with parasitic clearance. Conclusion AL remains an efficacious drug for the treatment of uncomplicated falciparum malaria in Benin, although higher rates of re-infection remain a concern. Surveillance needs to be continued to detect future changes in parasite sensitivity to artemisinin-based combination therapy.
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Affiliation(s)
- Aurore Ogouyèmi-Hounto
- Unité d'Enseignement et de Recherche en Parasitologie Mycologie/Faculté des Sciences de la Santé, laboratoire du Centre de Lutte intégrée contre le paludisme, 01 BP188, Cotonou, Benin. .,Laboratoire du Centre de Lutte intégrée contre le paludisme, 01 BP188, Cotonou, Benin.
| | | | - Souliatou Lawani
- Laboratoire du Centre de Lutte intégrée contre le paludisme, 01 BP188, Cotonou, Benin.
| | - Georgia Damien
- UMR 224-MIVEGEC, Institut de Recherche pour le Développement, 08 BP 841, Cotonou, Benin.
| | - Yolande Sissinto Savi de Tove
- Unité d'Enseignement et de Recherche en Parasitologie Mycologie/Faculté des Sciences de la Santé, laboratoire du Centre de Lutte intégrée contre le paludisme, 01 BP188, Cotonou, Benin. .,Laboratoire du Centre de Lutte intégrée contre le paludisme, 01 BP188, Cotonou, Benin.
| | - Franck Remoue
- UMR 224-MIVEGEC, Institut de Recherche pour le Développement, 08 BP 841, Cotonou, Benin.
| | - Dorothée Kinde Gazard
- Unité d'Enseignement et de Recherche en Parasitologie Mycologie/Faculté des Sciences de la Santé, laboratoire du Centre de Lutte intégrée contre le paludisme, 01 BP188, Cotonou, Benin. .,Laboratoire du Centre de Lutte intégrée contre le paludisme, 01 BP188, Cotonou, Benin.
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Londono-Renteria B, Drame PM, Weitzel T, Rosas R, Gripping C, Cardenas JC, Alvares M, Wesson DM, Poinsignon A, Remoue F, Colpitts TM. An. gambiae gSG6-P1 evaluation as a proxy for human-vector contact in the Americas: a pilot study. Parasit Vectors 2015; 8:533. [PMID: 26464073 PMCID: PMC4605097 DOI: 10.1186/s13071-015-1160-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 10/08/2015] [Indexed: 11/26/2022] Open
Abstract
Background During blood meal, the female mosquito injects saliva able to elicit an immune response in the vertebrate. This immune response has been proven to reflect the intensity of exposure to mosquito bites and risk of infection for vector transmitted pathogens such as malaria. The peptide gSG6-P1 of An. gambiae saliva has been demonstrated to be antigenic and highly specific to Anopheles as a genus. However, the applicability of gSG6-P1 to measure exposure to different Anopheles species endemic in the Americas has yet to be evaluated. The purpose of this pilot study was to test whether human participants living in American countries present antibodies able to recognize the gSG6-P1, and whether these antibodies are useful as a proxy for mosquito bite exposure and malaria risk. Methods We tested human serum samples from Colombia, Chile, and the United States for the presence of IgG antibodies against gSG6-P1 by ELISA. Antibody concentrations were expressed as delta optical density (ΔOD) of each sera tested in duplicates. The difference in the antibody concentrations between groups was tested using the nonparametric Mann Whitney test (independent groups) and the nonparametric Wilcoxon matched-pairs signed rank test (dependent groups). All differences were considered significant with a P < 0.05. Results We found that the concentration of gSG6-P1 antibodies was significantly correlated with malaria infection status and mosquito bite exposure history. People with clinical malaria presented significantly higher concentrations of IgG anti-gSG6-P1 antibodies than healthy controls. Additionally, a significant raise in antibody concentrations was observed in subjects returning from malaria endemic areas. Conclusion Our data shows that gSG6-P1 is a suitable candidate for the evaluation of exposure to Anopheles mosquito bites, risk of malaria transmission, and effectiveness of protection measures against mosquito bites in the Americas.
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Affiliation(s)
- Berlin Londono-Renteria
- Department of Pathology, Microbiology and Immunology, University of South Carolina, Columbia, SC, USA. .,Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, 6439 Garners Ferry Rd, Bldg 2 Rm C3, Columbia, SC, 29209, USA.
| | - Papa M Drame
- Laboratory of Parasitic Diseases, National Institutes of Health, NIAID, Bethesda, MD, USA.
| | - Thomas Weitzel
- Laboratorio Clínico/Programa Medicina del Viajero, Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.
| | | | - Crystal Gripping
- Department of Tropical Medicine, Tulane University, New Orleans, LA, USA.
| | | | - Marcela Alvares
- Hospital Emiro Quintero Canizales, Ocana, Norte de Santander, Colombia.
| | - Dawn M Wesson
- Department of Tropical Medicine, Tulane University, New Orleans, LA, USA.
| | - Anne Poinsignon
- Institut de Recherche pour le Développement-IRD, Bouaké, Côte d'Ivoire.
| | - Franck Remoue
- Institut de Recherche pour le Développement-IRD, Bouaké, Côte d'Ivoire.
| | - Tonya M Colpitts
- Department of Pathology, Microbiology and Immunology, University of South Carolina, Columbia, SC, USA.
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Marie A, Ronca R, Poinsignon A, Lombardo F, Drame PM, Cornelie S, Besnard P, Le Mire J, Fiorentino G, Fortes F, Carnevale P, Remoue F, Arcà B. The Anopheles gambiae cE5 salivary protein: a sensitive biomarker to evaluate the efficacy of insecticide-treated nets in malaria vector control. Microbes Infect 2015; 17:409-16. [PMID: 25637950 DOI: 10.1016/j.micinf.2015.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 01/21/2015] [Accepted: 01/22/2015] [Indexed: 11/26/2022]
Abstract
Evaluation of vector control is crucial for improving malaria containment and, according to World Health Organization, new complementary indicators would be very valuable. In this study the IgG response to the Anopheles-specific cE5 salivary protein was tested as a tool to evaluate the efficacy of insecticide-treated nets in reducing human exposure to malaria vectors. Sera collected during a longitudinal study carried out in Angola, and including entomological and parasitological data, were used to assess the IgG response to the Anopheles gambiae cE5 in both children and adults, before and after the application of insecticide-treated nets. Seasonal fluctuation of specific IgG antibody levels according to exposure was only found in children (up to ≈ 14 years old) whose anti-cE5 IgG response dropped after bed nets installation. These results were fully consistent with previous findings obtained with the same set of sera and indicating a substantial reduction of human-vector contact shortly after nets implementation. Overall, children IgG response to the cE5 protein appeared a very sensitive biomarker, which allowed for the detection of even weak exposure to Anopheles bites, indicating it may represent a reliable additional tool to evaluate the efficacy of vector control interventions.
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Affiliation(s)
- Alexandra Marie
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France.
| | - Raffaele Ronca
- Department of Biology, "Federico II" University, Via Cinthia, 80126 Naples, Italy
| | - Anne Poinsignon
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France
| | - Fabrizio Lombardo
- Department of Public Health and Infectious Diseases, Parasitology Section, Sapienza University, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Papa M Drame
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France
| | - Sylvie Cornelie
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France; MIVEGEC-IRD-CREC, 01 BP44 RP Cotonou, Benin
| | | | | | - Gabriella Fiorentino
- Department of Biology, "Federico II" University, Via Cinthia, 80126 Naples, Italy
| | - Filomeno Fortes
- Malaria Control Program, Ministry of Public Health, Luanda, Angola
| | | | - Franck Remoue
- MIVEGEC, UMR IRD-224 CNRS-5290 UM1-UM2, 911 Av. Agropolis, 34394 Montpellier Cedex 5, France
| | - Bruno Arcà
- Department of Public Health and Infectious Diseases, Parasitology Section, Sapienza University, Piazzale Aldo Moro 5, 00185 Rome, Italy.
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Marie A, Holzmuller P, Tchioffo MT, Rossignol M, Demettre E, Seveno M, Corbel V, Awono-Ambéné P, Morlais I, Remoue F, Cornelie S. Anopheles gambiae salivary protein expression modulated by wild Plasmodium falciparum infection: highlighting of new antigenic peptides as candidates of An. gambiae bites. Parasit Vectors 2014; 7:599. [PMID: 25526764 PMCID: PMC4287575 DOI: 10.1186/s13071-014-0599-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 12/10/2014] [Indexed: 12/24/2022] Open
Abstract
Background Malaria is the major parasitic disease worldwide caused by Plasmodium infection. The objective of integrated malaria control programs is to decrease malaria transmission, which needs specific tools to be accurately assessed. In areas where the transmission is low or has been substantially reduced, new complementary tools have to be developed to improve surveillance. A recent approach, based on the human antibody response to Anopheles salivary proteins, has been shown to be efficient in evaluating human exposure to Anopheles bites. The aim of the present study was to identify new An. gambiae salivary proteins as potential candidate biomarkers of human exposure to P. falciparum-infective bites. Methods Experimental infections of An. gambiae by wild P. falciparum were carried out in semi-field conditions. Then a proteomic approach, combining 2D-DIGE and mass spectrometry, was used to identify the overexpressed salivary proteins in infected salivary glands compared to uninfected An. gambiae controls. Subsequently, a peptide design of each potential candidate was performed in silico and their antigenicity was tested by an epitope-mapping technique using blood from individuals exposed to Anopheles bites. Results Five salivary proteins (gSG6, gSG1b, TRIO, SG5 and long form D7) were overexpressed in the infected salivary glands. Eighteen peptides were designed from these proteins and were found antigenic in children exposed to the Anopheles bites. Moreover, the results showed that the presence of wild P. falciparum in salivary glands modulates the expression of several salivary proteins and also appeared to induce post-translational modifications. Conclusions This study is, to our knowledge, the first that compares the sialome of An. gambiae both infected and not infected by wild P. falciparum, making it possible to mimic the natural conditions of infection. This is a first step toward a better understanding of the close interactions between the parasite and the salivary gland of mosquitoes. In addition, these results open the way to define biomarkers of infective bites of Anopheles, which could, in the future, improve the estimation of malaria transmission and the evaluation of malaria vector control tools. Electronic supplementary material The online version of this article (doi:10.1186/s13071-014-0599-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alexandra Marie
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France.
| | - Philippe Holzmuller
- CIRAD Département Systèmes Biologiques BIOS UMR 15 CMAEE "Contrôle des Maladies Exotiques et Emergentes", Campus International de Baillarguet, TA A-15/G, Montpellier cedex 5, 34398, France.
| | - Majoline T Tchioffo
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France.
| | - Marie Rossignol
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France.
| | - Edith Demettre
- Institut de Génomique Fonctionnelle, CNRS UMR 5203, INSERM U661, UM1, UM2, Plate-forme de Protéomique Fonctionnelle CNRS UMS BioCampus 3426, Montpellier, 34094, France.
| | - Martial Seveno
- Institut de Génomique Fonctionnelle, CNRS UMR 5203, INSERM U661, UM1, UM2, Plate-forme de Protéomique Fonctionnelle CNRS UMS BioCampus 3426, Montpellier, 34094, France.
| | - Vincent Corbel
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France. .,Department of Entomology, Faculty of Agriculture, Kasetsart University, 50 Ngam Wong Wan Rd, Ladyaow Chatuchak, Bangkok, 10900, Thailand.
| | - Parfait Awono-Ambéné
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, BP 288, Cameroun.
| | - Isabelle Morlais
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France. .,Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, BP 288, Cameroun.
| | - Franck Remoue
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France.
| | - Sylvie Cornelie
- MIVEGEC (UMR IRD224 CNRS 5290 UM1-UM2), Institut de Recherche pour le développement (IRD), 911 avenue Agropolis, Montpellier cedex 5, 34394, France. .,MIVEGEC- IRD- CREC, Cotonou, 01 BP4414 RP, Bénin.
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Ndille EE, Dubot-Pérès A, Doucoure S, Mouchet F, Cornelie S, Sidavong B, Fournet F, Remoue F. Human IgG antibody response to Aedes aegypti Nterm-34 kDa salivary peptide as an indicator to identify areas at high risk for dengue transmission: a retrospective study in urban settings of Vientiane city, Lao PDR. Trop Med Int Health 2014; 19:576-80. [PMID: 24641205 DOI: 10.1111/tmi.12280] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE Using human IgG antibody response to the Aedes Nterm-34 kDa salivary peptide as an indicator of human exposure to Aedes bites in surveying exposed populations from areas at risk of dengue virus (DENV) transmission in urban settings of Vientiane city, Lao PDR. METHODS Enzyme-linked immunosorbent assay tests were performed to measure the IgG response to Nterm-34 kDa peptide in blood samples collected within a flavivirus seroprevalence survey carried out in 2006 including 3558 randomly selected individuals. The level of IgG response to the Nterm-34 kDa peptide in individuals was analysed in relation to the level of urbanisation of the individual's residence, areas that presented significant differences in the prevalence of recent DENV infection. RESULTS No differences were observed in the anti-Nterm-34 kDa IgG level between DENV-positive and DENV-negative individuals. However, the level of specific IgG response was higher among individuals living in slightly urbanised neighbourhoods than among those in more highly urbanised areas (P < 0.0001). Interestingly, a similar pattern had already been observed concerning the prevalence of recent DENV infection in the same populations. CONCLUSION The results of this retrospective study indicate that the evaluation of human IgG response to the Aedes Nterm-34 kDa salivary peptide could be a useful indicator to identify places with risk of dengue virus transmission in urban endemic areas.
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Affiliation(s)
- Emmanuel Elanga Ndille
- Institut de recherche pour le développement (IRD), UMR Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle, UMR IRD 224 - CNRS 5290 - Universities of Montpellier 1 and 2, Cotonou, Bénin; Centre de Recherche Entomologique de Cotonou, Ministère de la Santé Publique, Cotonou, Bénin
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Gaayeb L, Sarr JB, Cames C, Pinçon C, Hanon JB, Ndiath MO, Seck M, Herbert F, Sagna AB, Schacht AM, Remoue F, Riveau G, Hermann E. Effects of malnutrition on children's immunity to bacterial antigens in Northern Senegal. Am J Trop Med Hyg 2014; 90:566-73. [PMID: 24445198 DOI: 10.4269/ajtmh.12-0657] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
To evaluate immunity to vaccine-preventable diseases according to nutritional status, a longitudinal study was conducted in Senegalese children ages 1-9 years old. A linear regression analysis predicted that weight for age was positively associated with immunoglobulin G (IgG) response to tetanus toxoid in children born during the rainy season or at the beginning of the dry season. A relationship between village, time of visits, and levels of antibodies to tetanus showed that environmental factors played a role in modulating humoral immunity to tetanus vaccine over time. Moreover, a whole-blood stimulation assay highlighted that the production of interferon-γ (IFN-γ) in response to tetanus toxoid was compromised in stunted children. However, the absence of cytokine modulation in response to Mycobacterium tuberculosis-purified protein derivatives and phytohemagglutinin suggests that the overall ability to produce IFN-γ was preserved in stunted children. Therefore, these results show that nutritional status can specifically alter the efficacy of long-lasting immunity to tetanus.
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Affiliation(s)
- Lobna Gaayeb
- Center for Infection and Immunity of Lille (CIIL)-U1019 Inserm, Unité Mixte de Recherche (UMR) 8204 Centre National de la Recherche Scientifique (CNRS), Université Lille Nord de France, Institut Pasteur de Lille, Lille, France; Centre de Recherche Biomédicale Espoir Pour la Santé (EPLS), Saint-Louis, Senegal; Institut de Recherche pour le Développement Unité Mixte Internationale (UMI) 233 TransVIHmi, Centre Régional de Recherche et de Formation à la prise en charge Clinique, Centre Hospitalier Universitaire de Fann, Dakar, Senegal; Department of Biostatistics, Faculté de Pharmacie de Lille, Université Lille Nord de France, Lille, France; UMR198 URMITE, Campus International, Institut de Recherche pour le Développement, Université Cheikh Anta Diop de Dakar (UCAD), Institut de Recherche pour le Développement Hann, Dakar, Senegal; UMR Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Institut de Recherche pour le Développement 224, CNRS5290, Université de Montpellier 1 et 2, Institut de Recherche pour le Développement, Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Benin
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Dama E, Cornelie S, Camara M, Somda MB, Poinsignon A, Ilboudo H, Elanga Ndille E, Jamonneau V, Solano P, Remoue F, Bengaly Z, Belem AMG, Bucheton B. In silico identification of a candidate synthetic peptide (Tsgf118-43) to monitor human exposure to tsetse flies in West Africa. PLoS Negl Trop Dis 2013; 7:e2455. [PMID: 24086785 PMCID: PMC3784472 DOI: 10.1371/journal.pntd.0002455] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 08/12/2013] [Indexed: 01/31/2023] Open
Abstract
Background The analysis of humoral responses directed against the saliva of blood-sucking arthropods was shown to provide epidemiological biomarkers of human exposure to vector-borne diseases. However, the use of whole saliva as antigen presents several limitations such as problems of mass production, reproducibility and specificity. The aim of this study was to design a specific biomarker of exposure to tsetse flies based on the in silico analysis of three Glossina salivary proteins (Ada, Ag5 and Tsgf1) previously shown to be specifically recognized by plasma from exposed individuals. Methodology/Principal Findings Synthetic peptides were designed by combining several linear epitope prediction methods and Blast analysis. The most specific peptides were then tested by indirect ELISA on a bank of 160 plasma samples from tsetse infested areas and tsetse free areas. Anti-Tsgf118–43 specific IgG levels were low in all three control populations (from rural Africa, urban Africa and Europe) and were significantly higher (p<0.0001) in the two populations exposed to tsetse flies (Guinean HAT foci, and South West Burkina Faso). A positive correlation was also found between Anti-Tsgf118–43 IgG levels and the risk of being infected by Trypanosoma brucei gambiense in the sleeping sickness foci of Guinea. Conclusion/Significance The Tsgf118–43 peptide is a suitable and promising candidate to develop a standardize immunoassay allowing large scale monitoring of human exposure to tsetse flies in West Africa. This could provide a new surveillance indicator for tsetse control interventions by HAT control programs. Increasing interest is paid to blood-sucking arthropod's salivary antigens to develop host direct biomarkers of exposure. Nevertheless use of whole saliva is problematic both because of mass production and specificity issues. Here, we describe an in silico approach we used to identify potential epitopes on the amino acid sequence of three tsetse salivary proteins (Ada, Ag5 and Tsgf1) that were previously shown to be specifically recognized by antibodies from exposed individuals. Three candidate peptides were synthesized and evaluated on a set of plasma collected in different tsetse-infested and tsetse-free areas. The Tsgf118–43 synthetic peptide appeared as a promising candidate to assess human exposure to tsetse flies as antibody responses were low in all three control groups and were significantly higher in our two exposed groups. Significantly higher anti- Tsgf118–43 responses were also observed in sleeping sickness patients as compared to uninfected controls suggesting that Tsgf118–43 may be used both to assess human tsetse contacts and the risk of infection by trypanosomes. This new sero-epidemiological tool could thus help National Control Programs to quickly map human exposure levels in order to better target vector control efforts and monitor vector control efficiency.
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Affiliation(s)
- Emilie Dama
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
| | - Sylvie Cornelie
- Institut de Recherche pour le Développement (IRD), UMR MIVEGEC IRD 224-CNRS 5290-Université de Montpellier 1 et Montpellier 2, Montpellier, France
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Mamadou Camara
- Programme National de Lutte contre la Trypanosomose Humaine Africaine en Guinée, Conakry, Guinée
| | - Martin Bienvenu Somda
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
| | - Anne Poinsignon
- Institut de Recherche pour le Développement (IRD), UMR MIVEGEC IRD 224-CNRS 5290-Université de Montpellier 1 et Montpellier 2, Montpellier, France
| | - Hamidou Ilboudo
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
| | - Emmanuel Elanga Ndille
- Institut de Recherche pour le Développement (IRD), UMR MIVEGEC IRD 224-CNRS 5290-Université de Montpellier 1 et Montpellier 2, Montpellier, France
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Vincent Jamonneau
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
- Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Campus International de Baillarguet, Montpellier, France
| | - Philippe Solano
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
- Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Campus International de Baillarguet, Montpellier, France
| | - Franck Remoue
- Institut de Recherche pour le Développement (IRD), UMR MIVEGEC IRD 224-CNRS 5290-Université de Montpellier 1 et Montpellier 2, Montpellier, France
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Zakaria Bengaly
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
| | | | - Bruno Bucheton
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
- Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Campus International de Baillarguet, Montpellier, France
- * E-mail:
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Sagna AB, Gaayeb L, Sarr JB, Senghor S, Poinsignon A, Boutouaba-Combe S, Schacht AM, Hermann E, Faye N, Remoue F, Riveau G. Plasmodium falciparum infection during dry season: IgG responses to Anopheles gambiae salivary gSG6-P1 peptide as sensitive biomarker for malaria risk in Northern Senegal. Malar J 2013; 12:301. [PMID: 23988032 PMCID: PMC3766161 DOI: 10.1186/1475-2875-12-301] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 08/27/2013] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The Northern part of Senegal is characterized by a low and seasonal transmission of malaria. However, some Plasmodium falciparum infections and malaria clinical cases are reported during the dry season. This study aims to assess the relationship between IgG antibody (Ab) responses to gSG6-P1 mosquito salivary peptide and the prevalence of P. falciparum infection in children during the dry season in the Senegal River Valley. The positive association of the Ab response to gSG6-P1, as biomarker of human exposure to Anopheles vector bite, and P. falciparum infectious status (uninfected, infected-asymptomatic or infected-symptomatic) will allow considering this biomarker as a potential indicator of P. falciparum infection risk during the dry season. METHODS Microscopic examination of thick blood smears was performed in 371 and 310 children at the start (January) and at the end (June) of the dry season, respectively, in order to assess the prevalence of P. falciparum infection. Collected sera were used to evaluate IgG response to gSG6-P1 by ELISA. Association between parasitological and clinical data (infected-asymptomatic or infected-symptomatic) and the anti-gSG6-P1 IgG levels were evaluated during this period. RESULTS The prevalence of P. falciparum infection was very low to moderate according to the studied period and was higher in January (23.5%) compared to June (3.5%). Specific IgG response was also different between uninfected children and asymptomatic carriers of the parasite. Children with P. falciparum infection in the dry season showed higher IgG Ab levels to gSG6-P1 than uninfected children. CONCLUSIONS The results strengthen the hypothesis that malaria transmission is maintained during the dry season in an area of low and seasonal transmission. The measurement of IgG responses to gSG6-P1 salivary peptide could be a pertinent indicator of human malaria reservoir or infection risk in this particular epidemiological context. This promising immunological marker could be useful for the evaluation of the risk of P. falciparum exposure observed during dry season and, by consequences, could be used for the survey of potential pre-elimination situation.
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Affiliation(s)
- André B Sagna
- Centre de Recherche Biomédicale Espoir Pour La Santé, 269 Route de la corniche, Sor, BP: 226, Saint-Louis, Sénégal
- Département de Biologie Animale, Laboratoire de parasitologie générale, Université Cheikh Anta Diop, Dakar, Sénégal
| | - Lobna Gaayeb
- Centre de Recherche Biomédicale Espoir Pour La Santé, 269 Route de la corniche, Sor, BP: 226, Saint-Louis, Sénégal
- CIIL, Inserm U1019, CNRS UMR 8204, Université Lille Nord de France, Institut Pasteur de Lille, 1 rue du Pr. Calmette, 59019 Lille cedex, France
| | - Jean B Sarr
- Centre de Recherche Biomédicale Espoir Pour La Santé, 269 Route de la corniche, Sor, BP: 226, Saint-Louis, Sénégal
- Institut de Recherche pour le Développement, UMR 224 MIVEGEC, 911 avenue Agropolis, BP: 64501F-34394 Montpellier, France
| | - Simon Senghor
- Centre de Recherche Biomédicale Espoir Pour La Santé, 269 Route de la corniche, Sor, BP: 226, Saint-Louis, Sénégal
| | - Anne Poinsignon
- Institut de Recherche pour le Développement, UMR 224 MIVEGEC, 911 avenue Agropolis, BP: 64501F-34394 Montpellier, France
| | - Samy Boutouaba-Combe
- Centre de Recherche Biomédicale Espoir Pour La Santé, 269 Route de la corniche, Sor, BP: 226, Saint-Louis, Sénégal
| | - Anne-Marie Schacht
- Centre de Recherche Biomédicale Espoir Pour La Santé, 269 Route de la corniche, Sor, BP: 226, Saint-Louis, Sénégal
- CIIL, Inserm U1019, CNRS UMR 8204, Université Lille Nord de France, Institut Pasteur de Lille, 1 rue du Pr. Calmette, 59019 Lille cedex, France
| | - Emmanuel Hermann
- CIIL, Inserm U1019, CNRS UMR 8204, Université Lille Nord de France, Institut Pasteur de Lille, 1 rue du Pr. Calmette, 59019 Lille cedex, France
| | - Ngor Faye
- Département de Biologie Animale, Laboratoire de parasitologie générale, Université Cheikh Anta Diop, Dakar, Sénégal
| | - Franck Remoue
- Institut de Recherche pour le Développement, UMR 224 MIVEGEC, 911 avenue Agropolis, BP: 64501F-34394 Montpellier, France
- Centre de Recherche Entomologique de Cotonou, BP: 4414, Cotonou RP 01, Bénin
| | - Gilles Riveau
- Centre de Recherche Biomédicale Espoir Pour La Santé, 269 Route de la corniche, Sor, BP: 226, Saint-Louis, Sénégal
- CIIL, Inserm U1019, CNRS UMR 8204, Université Lille Nord de France, Institut Pasteur de Lille, 1 rue du Pr. Calmette, 59019 Lille cedex, France
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Doucoure S, Cornelie S, Patramool S, Mouchet F, Demettre E, Seveno M, Dehecq JS, Rutee H, Herve JP, Favier F, Missé D, Gasque P, Remoue F. First screening of Aedes albopictus immunogenic salivary proteins. Insect Mol Biol 2013; 22:411-423. [PMID: 23714164 DOI: 10.1111/imb.12032] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Study of the human antibody (Ab) response to Aedes salivary proteins can provide new biomarkers to evaluate human exposure to vector bites. The identification of genus- and/or species-specific proteins is necessary to improve the accuracy of biomarkers. We analysed Aedes albopictus immunogenic salivary proteins by 2D immunoproteomic technology and compared the profiles according to human individual exposure to Ae. albopictus or Ae. aegypti bites. Strong antigenicity to Ae. albopictus salivary proteins was detected in all individuals whatever the nature of Aedes exposure. Amongst these antigenic proteins, 68% are involved in blood feeding, including D7 protein family, adenosine deaminase, serpin and apyrase. This study provides an insight into the repertoire of Ae. albopictus immunogenic salivary proteins for the first time.
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Affiliation(s)
- S Doucoure
- MIVEGEC: Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle, , Universities of Montpellier 1 and 2., Montpellier, France.
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Marie A, Boissière A, Tsapi MT, Poinsignon A, Awono-Ambéné PH, Morlais I, Remoue F, Cornelie S. Evaluation of a real-time quantitative PCR to measure the wild Plasmodium falciparum infectivity rate in salivary glands of Anopheles gambiae. Malar J 2013; 12:224. [PMID: 23819831 PMCID: PMC3707787 DOI: 10.1186/1475-2875-12-224] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 06/04/2013] [Indexed: 12/15/2022] Open
Abstract
Background Evaluation of malaria sporozoite rates in the salivary glands of Anopheles gambiae is essential for estimating the number of infective mosquitoes, and consequently, the entomological inoculation rate (EIR). EIR is a key indicator for evaluating the risk of malaria transmission. Although the enzyme-linked immunosorbent assay specific for detecting the circumsporozoite protein (CSP-ELISA) is routinely used in the field, it presents several limitations. A multiplex PCR can also be used to detect the four species of Plasmodium in salivary glands. The aim of this study was to evaluate the efficacy of a real-time quantitative PCR in detecting and quantifying wild Plasmodium falciparum in the salivary glands of An. gambiae. Methods Anopheles gambiae (n=364) were experimentally infected with blood from P. falciparum gametocyte carriers, and P. falciparum in the sporozoite stage were detected in salivary glands by using a real-time quantitative PCR (qPCR) assay. The sensitivity and specificity of this qPCR were compared with the multiplex PCR applied from the Padley method. CSP-ELISA was also performed on carcasses of the same mosquitoes. Results The prevalence of P. falciparum and the intensity of infection were evaluated using qPCR. This method had a limit of detection of six sporozoites per μL based on standard curves. The number of P. falciparum genomes in the salivary gland samples reached 9,262 parasites/μL (mean: 254.5; 95% CI: 163.5-345.6). The qPCR showed a similar sensitivity (100%) and a high specificity (60%) compared to the multiplex PCR. The agreement between the two methods was “substantial” (κ = 0.63, P <0.05). The number of P. falciparum-positive mosquitoes evaluated with the qPCR (76%), multiplex PCR (59%), and CSP-ELISA (83%) was significantly different (P <0.005). Conclusions The qPCR assay can be used to detect P. falciparum in salivary glands of An. gambiae. The qPCR is highly sensitive and is more specific than multiplex PCR, allowing an accurate measure of infective An. gambiae. The results also showed that the CSP-ELISA overestimates the sporozoite rate, detecting sporozoites in the haemolymph in addition to the salivary glands.
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Affiliation(s)
- Alexandra Marie
- Laboratoire MIVEGEC (UMR IRD 224 CNRS 5290 UM1-UM2), 911 Av, Agropolis, 34394 Montpellier Cedex 5, France.
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Drame PM, Diallo A, Poinsignon A, Boussari O, Dos Santos S, Machault V, Lalou R, Cornelie S, LeHesran JY, Remoue F. Evaluation of the effectiveness of malaria vector control measures in urban settings of Dakar by a specific anopheles salivary biomarker. PLoS One 2013; 8:e66354. [PMID: 23840448 PMCID: PMC3688790 DOI: 10.1371/journal.pone.0066354] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 05/09/2013] [Indexed: 11/24/2022] Open
Abstract
Standard entomological methods for evaluating the impact of vector control lack sensitivity in low-malaria-risk areas. The detection of human IgG specific to Anopheles gSG6-P1 salivary antigen reflects a direct measure of human–vector contact. This study aimed to assess the effectiveness of a range of vector control measures (VCMs) in urban settings by using this biomarker approach. The study was conducted from October to December 2008 on 2,774 residents of 45 districts of urban Dakar. IgG responses to gSG6-P1 and the use of malaria VCMs highly varied between districts. At the district level, specific IgG levels significantly increased with age and decreased with season and with VCM use. The use of insecticide-treated nets, by drastically reducing specific IgG levels, was by far the most efficient VCM regardless of age, season or exposure level to mosquito bites. The use of spray bombs was also associated with a significant reduction of specific IgG levels, whereas the use of mosquito coils or electric fans/air conditioning did not show a significant effect. Human IgG response to gSG6-P1 as biomarker of vector exposure represents a reliable alternative for accurately assessing the effectiveness of malaria VCM in low-malaria-risk areas. This biomarker tool could be especially relevant for malaria control monitoring and surveillance programmes in low-exposure/low-transmission settings.
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Affiliation(s)
- Papa Makhtar Drame
- Institut de Recherche pour le Développement (IRD), UMR-MIVEGEC (IRD224-CNRS5290- Universites Montpellier 1 et 2), Montpellier, France.
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Somda MB, Bengaly Z, Dama E, Poinsignon A, Dayo GK, Sidibe I, Remoue F, Sanon A, Bucheton B. First insights into the cattle serological response to tsetse salivary antigens: a promising direct biomarker of exposure to tsetse bites. Vet Parasitol 2013; 197:332-40. [PMID: 23800781 DOI: 10.1016/j.vetpar.2013.05.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 05/17/2013] [Accepted: 05/18/2013] [Indexed: 11/29/2022]
Abstract
In the context of the Pan African Tsetse and Trypanosomiasis Eradication Campaign, the value of tsetse saliva antibodies as a biomarker of cattle exposure to tsetse flies was evaluated, as this could provide an alternative and complementary tool to conventional entomological methods. Serum immune reactivity to Glossina (G.) palpalis (p.) gambiensis, G. tachinoides and G. morsitans (m.) submorsitans whole saliva extracts (WSE) were monitored in cattle from both tsetse free and tsetse infested areas, and in cows experimentally exposed to tsetse flies and other hematophagous arthropods. In the tsetse infested area, cattle IgG responses to Glossina WSE were significantly higher during the dry season (p<0.0001) when herds are most exposed to tsetse flies and in infected animals (p=0.01) as expected in the case of a biomarker of exposure. Experimental studies further confirmed this as a quick rise of specific IgGs was observed in animals exposed to tsetse flies (within weeks), followed by a rapid clearance after exposure was stopped. In contrast to the two other tsetse species, G. m. submorsitans WSE enabled to detect exposure to all tsetse species and were associated with low level of cross-reactivity to other blood sucking arthropods. Finally, IgG responses to G. m. submorsitans salivary antigens enabled to distinguish different groups of cows according to exposure levels, thus indicating that tsetse saliva antibodies are not only indicators of tsetse exposure but also are correlated to the intensity of tsetse contacts (p=0.0031). Implementation of this new sero-epidemiological marker of cattle exposure to tsetse flies in the framework of tsetse elimination campaigns is discussed.
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Affiliation(s)
- Martin Bienvenu Somda
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide, 01 BP 454, Bobo-Dioulasso 01, Burkina Faso.
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Sagna AB, Sarr JB, Gaayeb L, Drame PM, Ndiath MO, Senghor S, Sow CS, Poinsignon A, Seck M, Hermann E, Schacht AM, Faye N, Sokhna C, Remoue F, Riveau G. gSG6-P1 salivary biomarker discriminates micro-geographical heterogeneity of human exposure to Anopheles bites in low and seasonal malaria areas. Parasit Vectors 2013; 6:68. [PMID: 23497646 PMCID: PMC3631127 DOI: 10.1186/1756-3305-6-68] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 03/08/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Over the past decade, a sharp decline of malaria burden has been observed in several countries. Consequently, the conventional entomological methods have become insufficiently sensitive and probably under-estimate micro-geographical heterogeneity of exposure and subsequent risk of malaria transmission. In this study, we investigated whether the human antibody (Ab) response to Anopheles salivary gSG6-P1 peptide, known as a biomarker of Anopheles exposure, could be a sensitive and reliable tool for discriminating human exposure to Anopheles bites in area of low and seasonal malaria transmission. METHODS A multi-disciplinary survey was performed in Northern Senegal where An. gambiae s.l. is the main malaria vector. Human IgG Ab response to gSG6-P1 salivary peptide was compared according to the season and villages in children from five villages in the middle Senegal River valley, known as a low malaria transmission area. RESULTS IgG levels to gSG6-P1 varied considerably according to the villages, discriminating the heterogeneity of Anopheles exposure between villages. Significant increase of IgG levels to gSG6-P1 was observed during the peak of exposure to Anopheles bites, and decreased immediately after the end of the exposure season. In addition, differences in the season-dependent specific IgG levels between villages were observed after the implementation of Long-Lasting Insecticidal Nets by The National Malaria Control Program in this area. CONCLUSION The gSG6-P1 salivary peptide seems to be a reliable tool to discriminate the micro-geographical heterogeneity of human exposure to Anopheles bites in areas of very low and seasonal malaria transmission. A biomarker such as this could also be used to monitor and evaluate the possible heterogeneous effectiveness of operational vector control programs in low-exposure areas.
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Affiliation(s)
- André Barembaye Sagna
- Centre de Recherche Biomédicale (CRB) Espoir Pour La Santé, 269 Route de la corniche, Sor - BP: 226, Saint-Louis, Sénégal.
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Dama E, Cornelie S, Bienvenu Somda M, Camara M, Kambire R, Courtin F, Jamonneau V, Demettre E, Seveno M, Bengaly Z, Solano P, Poinsignon A, Remoue F, Belem AMG, Bucheton B. Identification of Glossina palpalis gambiensis specific salivary antigens: towards the development of a serologic biomarker of human exposure to tsetse flies in West Africa. Microbes Infect 2013; 15:416-27. [PMID: 23500186 DOI: 10.1016/j.micinf.2013.03.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 02/26/2013] [Accepted: 03/01/2013] [Indexed: 12/27/2022]
Abstract
The saliva of blood sucking arthropods contains a number of pharmacologically active compounds that induce an antibody response in exposed human individuals. The objectives of the present study were (i) to assess the human IgG response directed against salivary antigens of Glossina palpalis gambiensis, the main vector of Trypanosoma brucei gambiense in West Africa, as a biomarker of human-tsetse contacts; and (ii) to identify specific salivary antigens. Immune reactivity of human plasma collected within active human African trypanosomiasis (HAT) foci (coastal Guinea), historical foci where tsetse flies are still present (South-West Burkina Faso) and a tsetse free area (Bobo-Dioulasso, Burkina Faso), was measured by ELISA against whole saliva extracts. In the active HAT foci and areas where tsetse flies were present in high densities, specific IgG responses were significantly higher (p < 0.0001) to those in Bobo-Dioulasso or in Loropeni, where tsetse flies were either absent or only present at low densities. Furthermore, 2D-electrophoresis combined with mass spectrometry enabled to reveal that several antigens were specifically recognized by plasma from exposed individuals. Among them, four salivary proteins were successfully identified (Ada, 5'Nuc, Ag5 and Tsgf1). These results represent a first attempt to identify Glossina salivary proteins or synthetic peptides to develop a standardized and specific biomarker of tsetse exposure in West Africa.
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Affiliation(s)
- Emilie Dama
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide CIRDES, 01 BP 454 Bobo-Dioulasso 01, Burkina Faso
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Elanga Ndille E, Doucoure S, Damien G, Mouchet F, Drame PM, Cornelie S, Noukpo H, Yamadjako S, Djenontin A, Moiroux N, Misse D, Akogbeto M, Corbel V, Henry MC, Chandre F, Baldet T, Remoue F. First attempt to validate human IgG antibody response to Nterm-34kDa salivary peptide as biomarker for evaluating exposure to Aedes aegypti bites. PLoS Negl Trop Dis 2012; 6:e1905. [PMID: 23166852 PMCID: PMC3499371 DOI: 10.1371/journal.pntd.0001905] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Accepted: 10/01/2012] [Indexed: 11/19/2022] Open
Abstract
Background Much effort is being devoted for developing new indicators to evaluate the human exposure to Aedes mosquito bites and the risk of arbovirus transmission. Human antibody (Ab) responses to mosquito salivary components could represent a promising tool for evaluating the human-vector contact. Methodology/Principal findings To develop a specific biomarker of human exposure to Aedes aegypti bites, we measured IgG Ab response to Ae. aegypti Nterm-34 kDa salivary peptide in exposed children in 7 villages of Southern Benin (West Africa). Results showed that specific IgG response presented high inter-individual heterogeneity between villages. IgG response was associated with rainfall and IgG level increased from dry (low exposure) to rainy (high exposure) seasons. These findings indicate that IgG Ab to Nterm-34 kDa salivary peptide may represent a reliable biomarker to detect variation in human exposure to Ae. aegypti bites. Conclusion/Significance This preliminary study highlights the potential use of Ab response to this salivary peptide for evaluating human exposure to Ae. aegypti. This biomarker could represent a new promising tool for assessing the risk of arbovirus transmission and for evaluating the efficacy of vector control interventions. Aedes aegypti mosquito is the primary vector of major (re)-emerging human arboviruses, such as Dengue and Chikungunya. In absence of effective treatment and vaccine, the evaluation of human exposure to vector bites is crucial to estimate the risk of the viruses' transmission. Currently, exposure to Aedes aegypti bites is mainly evaluated by entomological methods which are indirect and fastidious to apply on a large scale. Human antibody (Ab) responses to arthropod salivary proteins were shown as a useful indicator of exposure to arthropod vector bites. Nevertheless, the whole saliva could not be a specific tool because some families of salivary proteins are common between many arthropod vectors. To develop a specific biomarker of exposure to Aedes aegypti bites, we assessed the evolution of IgG Ab response to Ae. aegypti Nterm-34 kDa salivary peptide in exposed children. The results indicate that children exposed to the bites of Ae. aegypti could develop specific Ab response to Nterm-34 kDa salivary peptide. This specific IgG response presented high inter-individual heterogeneity and increased significantly during the Ae. aegypti exposure season. Taken together, these preliminary results suggest that Ab responses to Nterm-34 kDa salivary could constitute a relevant immuno-epidemiological indicator for evaluating human exposure to the Ae. aegypti vector and by consequence the risk of arbovirus transmission.
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Affiliation(s)
- Emmanuel Elanga Ndille
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), UMR IRD 224 - CNRS 5290 - Universities of Montpellier 1, France.
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Brosseau L, Drame PM, Besnard P, Toto JC, Foumane V, Le Mire J, Mouchet F, Remoue F, Allan R, Fortes F, Carnevale P, Manguin S. Human antibody response to Anopheles saliva for comparing the efficacy of three malaria vector control methods in Balombo, Angola. PLoS One 2012; 7:e44189. [PMID: 23028499 PMCID: PMC3454387 DOI: 10.1371/journal.pone.0044189] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Accepted: 07/30/2012] [Indexed: 12/04/2022] Open
Abstract
Human antibody (Ab) response to Anopheles whole saliva, used as biomarker of Anopheles exposure, was investigated over a period of two years (2008–2009), in children between 2 to 9 years old, before and after the introduction of three different malaria vector control methods; deltamethrin treated long lasting impregnated nets (LLIN) and insecticide treated plastic sheeting (ITPS) - Zero Fly®) (ITPS-ZF), deltamethrin impregnated Durable (Wall) Lining (ITPS-DL – Zerovector®) alone, and indoor residual spraying (IRS) with lambdacyhalothrin alone. These different vector control methods resulted in considerable decreases in all three entomological (82.4%), parasitological (54.8%) and immunological criteria analyzed. The highest reductions in the number of Anopheles collected and number of positive blood smears, respectively 82.1% and 58.3%, were found in Capango and Canjala where LLIN and ITPS-ZF were implemented. The immunological data based on the level of anti-saliva IgG Ab in children of all villages dropped significantly from 2008 to 2009, except in Chissequele. These results indicated that these three vector control methods significantly reduced malaria infections amongst the children studied and IRS significantly reduced the human-Anopheles contact. The number of Anopheles, positive blood smears, and the levels of anti-saliva IgG Ab were most reduced when LLIN and ITPS-ZF were used in combination, compared to the use of one vector control method alone, either ITPS-DL or IRS. Therefore, as a combination of two vector control methods is significantly more effective than one control method only, this control strategy should be further developed at a more global scale.
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Affiliation(s)
- Laura Brosseau
- UMR-MD3, Institut de Recherche pour le Développement, Montpellier, France
| | - Papa Makhtar Drame
- UMR-MIVEGEC, Institut de Recherche pour le Développement, Montpellier, France
| | | | - Jean-Claude Toto
- Laboratoire de Recherche pour le Paludisme, Organisation de Coordination pour la lutte contre les Endémioes en Afrique Centrale, Yaoundé, Cameroun
| | - Vincent Foumane
- Laboratoire de Recherche pour le Paludisme, Organisation de Coordination pour la lutte contre les Endémioes en Afrique Centrale, Yaoundé, Cameroun
| | | | - François Mouchet
- UMR-MIVEGEC, Institut de Recherche pour le Développement, Montpellier, France
| | - Franck Remoue
- UMR-MIVEGEC, Institut de Recherche pour le Développement, Montpellier, France
| | | | | | - Pierre Carnevale
- Institut de Recherche pour le Développement, Montpellier, France
| | - Sylvie Manguin
- UMR-MD3, Institut de Recherche pour le Développement, Montpellier, France
- * E-mail:
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Badu K, Siangla J, Larbi J, Lawson BW, Afrane Y, Ong'echa J, Remoue F, Zhou G, Githeko AK, Yan G. Variation in exposure to Anopheles gambiae salivary gland peptide (gSG6-P1) across different malaria transmission settings in the western Kenya highlands. Malar J 2012; 11:318. [PMID: 22963464 PMCID: PMC3541077 DOI: 10.1186/1475-2875-11-318] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Accepted: 09/06/2012] [Indexed: 11/21/2022] Open
Abstract
Background The existing metrics of malaria transmission are limited in sensitivity under low transmission intensity. Robust surveillance systems are needed as interventions to monitor reduced transmission and prevention of rapid reintroduction. Serological tools based on antibody responses to parasite and vector antigens are potential tools for transmission measurements. The current study sought to evaluate antibody responses to Anopheles gambiae salivary gland peptide (gSG6- P1), as a biomarker of human exposure to Anopheles bites, in different transmission settings and seasons. The comparison between anti-MSP-119 IgG immune responders and non-responders allowed exploring the robustness of the gSG6-P1 peptide as a surveillance tool in an area of decreasing malaria transmission. Methods Total IgG levels to gSG6-P1 were measured in an age-stratified cohort (< 5, 5–14 and ≥ 15 years) in a total of 1,366 participants from three localities in western Kenya [Kisii (hypoendemic), Kakamega (mesoendemic), and Kombewa (hyperendemic)] including 607 sera that were additionally tested for MSP-119 specific responses during a low and a high malaria transmission seasons. Antibody prevalence and levels were compared between localities with different transmission intensities. Regression analysis was performed to examine the association between gSG6-P1 and MSP-119 seroprevalence and parasite prevalence. Result Seroprevalence of gSG6-P1 in the uphill population was 36% while it was 50% valley bottom (χ2 = 13.2, df = 1, p < 0.001). Median gSG6-P1 antibody levels in the Valley bottom were twice as high as that observed in the uphill population [4.50 vs. 2.05, p < 0.001] and showed seasonal variation. The odds of gSG6-P1 seropositives having MSP-119 antibodies were almost three times higher than the odds of seronegatives (OR = 2.87, 95% CI [1.977, 4.176]). The observed parasite prevalence for Kisii, Kakamega and Kombewa were 4%, 19.7% and 44.6% whilst the equivalent gSG6-P1 seroprevalence were 28%, 34% and 54%, respectively. Conclusion The seroprevalence of IgG to gSG6-P1 was sensitive and robust in distinguishing between hypo, meso and hyper transmission settings and seasonal fluctuations.
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Affiliation(s)
- Kingsley Badu
- Department of Theoretical and Applied Biology, College of Sciences, Kwame Nkrumah, University of Science & Technology, Kumasi, Ghana.
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Doucoure S, Mouchet F, Cournil A, Le Goff G, Cornelie S, Roca Y, Giraldez MG, Simon ZB, Loayza R, Misse D, Flores JV, Walter A, Rogier C, Herve JP, Remoue F. Human antibody response to Aedes aegypti saliva in an urban population in Bolivia: a new biomarker of exposure to Dengue vector bites. Am J Trop Med Hyg 2012; 87:504-10. [PMID: 22848099 DOI: 10.4269/ajtmh.2012.11-0477] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Aedes mosquitoes are important vectors of re-emerging diseases in developing countries, and increasing exposure to Aedes in the developed world is currently a source of concern. Given the limitations of current entomologic methods, there is a need for a new effective way for evaluating Aedes exposure. Our objective was to evaluate specific antibody responses to Aedes aegypti saliva as a biomarker for vector exposure in a dengue-endemic urban area. IgG responses to saliva were strong in young children and steadily waned with age. Specific IgG levels were significantly higher in persons living in sites with higher Ae. aegypti density, as measured by using entomologic parameters. Logistic regression showed a significant correlation between IgG to saliva and exposure level, independently of either age or sex. These results suggest that antibody responses to saliva could be used to monitor human exposure to Aedes bites.
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Affiliation(s)
- Souleymane Doucoure
- Institut de Recherche pour le Développement, Maladie Infectieuse et Vecteurs, Ecologie, Génétique, Evolution et Contrôle, Centre Institut de Recherche pour le Développement de Montpellier, Montpellier, France.
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Sarr JB, Samb B, Sagna AB, Fortin S, Doucoure S, Sow C, Senghor S, Gaayeb L, Guindo S, Schacht AM, Rogerie F, Hermann E, Dia I, Konate L, Riveau G, Remoue F. Differential acquisition of human antibody responses to Plasmodium falciparum according to intensity of exposure to Anopheles bites. Trans R Soc Trop Med Hyg 2012; 106:460-7. [PMID: 22721883 DOI: 10.1016/j.trstmh.2012.05.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 05/17/2012] [Accepted: 05/17/2012] [Indexed: 11/16/2022] Open
Abstract
Malaria immunity is modulated by many environmental and epidemiological factors. This study evaluates the influence of a hitherto unstudied environmental-epidemiological factor, namely the impact of human exposure to Anopheles bites on the isotype profile of acquired antibody responses to Plasmodium falciparum. In two Senegalese villages where the intensity of exposure to Anopheles bites was markedly different (high and low exposure), specific IgG1 and IgG3 responses to P. falciparum whole schizont extract (WSE) and circumsporozoite protein (CSP) were evaluated at the peak of Anopheles exposure (September) and later (December) in a cohort of 120 children aged 3-8 years. Multivariate analysis showed a significantly lower IgG1 response against P. falciparum WSE and CSP in children highly exposed to Anopheles bites (Gankette) compared to those who were weakly exposed (Mboula). In contrast, in both villages, parasitemia and increasing age were strongly associated with higher IgG1 and IgG3 levels. We hypothesize that high exposure to Anopheles bites could inhibit IgG1-dependent responsiveness to P. falciparum known to induce protective immune responses against malaria. The impact of mosquito saliva on the regulation of specific protective immunity may need to be taken into account in epidemiological studies and trials for malaria vaccines.
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Affiliation(s)
- Jean Biram Sarr
- Unité de recherche mixte MIVEGEC (IRD 224-CNRS 5290-UM1-UM2), Montpellier, France.
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Ndiath MO, Sarr JB, Gaayeb L, Mazenot C, Sougoufara S, Konate L, Remoue F, Hermann E, Trape JF, Riveau G, Sokhna C. Low and seasonal malaria transmission in the middle Senegal River basin: identification and characteristics of Anopheles vectors. Parasit Vectors 2012; 5:21. [PMID: 22269038 PMCID: PMC3274455 DOI: 10.1186/1756-3305-5-21] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 01/23/2012] [Indexed: 01/23/2023] Open
Abstract
Background During the last decades two dams were constructed along the Senegal River. These intensified the practice of agriculture along the river valley basin. We conducted a study to assess malaria vector diversity, dynamics and malaria transmission in the area. Methods A cross-sectional entomological study was performed in September 2008 in 20 villages of the middle Senegal River valley to evaluate the variations of Anopheles density according to local environment. A longitudinal study was performed, from October 2008 to January 2010, in 5 selected villages, to study seasonal variations of malaria transmission. Results Among malaria vectors, 72.34% of specimens collected were An. arabiensis, 5.28% An. gambiae of the S molecular form, 3.26% M form, 12.90% An. pharoensis, 4.70% An. ziemanni, 1.48% An. funestus and 0.04% An. wellcomei. Anopheles density varied according to village location. It ranged from 0 to 21.4 Anopheles/room/day and was significantly correlated with the distance to the nearest ditch water but not to the river. Seasonal variations of Anopheles density and variety were observed with higher human biting rates during the rainy season (8.28 and 7.55 Anopheles bite/man/night in October 2008 and 2009 respectively). Transmission was low and limited to the rainy season (0.05 and 0.06 infected bite/man/night in October 2008 and 2009 respectively). During the rainy season, the endophagous rate was lower, the anthropophagic rate higher and L1014F kdr frequency higher. Conclusions Malaria vectors are present at low-moderate density in the middle Senegal River basin with An. arabiensis as the predominant species. Other potential vectors are An. gambiae M and S form and An. funestus. Nonetheless, malaria transmission was extremely low and seasonal.
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Affiliation(s)
- Mamadou O Ndiath
- Institut de Recherche pour le Développement, UMR 198 URMITE Campus international de Hann, IRD BP 1386 CP 18524 Dakar, Sénégal.
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Sarr JB, Orlandi-Pradines E, Fortin S, Sow C, Cornelie S, Rogerie F, Guindo S, Konate L, Fusaï T, Riveau G, Rogier C, Remoue F. Assessment of exposure to Plasmodium falciparum transmission in a low endemicity area by using multiplex fluorescent microsphere-based serological assays. Parasit Vectors 2011; 4:212. [PMID: 22059951 PMCID: PMC3223141 DOI: 10.1186/1756-3305-4-212] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Accepted: 11/07/2011] [Indexed: 11/30/2022] Open
Abstract
Background The evaluation of malaria transmission intensity is a crucial indicator for estimating the burden of malarial disease. In this respect, entomological and parasitological methods present limitations, especially in low transmission areas. The present study used a sensitive multiplex assay to assess the exposure to Plasmodium falciparum infection in children living in an area of low endemicity. In three Senegalese villages, specific antibody (IgG) responses to 13 pre-erythrocytic P. falciparum peptides derived from Lsa1, Lsa3, Glurp, Salsa, Trap, Starp, Csp and Pf11.1 proteins were simultaneously evaluated before (June), at the peak (September) and after (December) the period of malaria transmission, in children aged from 1 to 8 years. Results Compared to other antigens, a high percentage of seropositivity and specific antibody levels were detected with Glurp, Salsa1, Lsa3NR2, and Lsa1J antigens. The seropositivity increased with age for all tested antigens. Specific IgG levels to Glurp, Salsa1, Lsa3NR2, and Lsa1J were significantly higher in P. falciparum infected children compared to non-infected and this increase is significantly correlated with parasite density. Conclusion The multiplex assay represents a useful technology for a serological assessment of rapid variations in malaria transmission intensity, especially in a context of low parasite rates. The use of such combined serological markers (i.e. Glurp, Lsa1, Lsa3, and Salsa) could offer the opportunity to examine these variations over time, and to evaluate the efficacy of integrated malaria control strategies.
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Rizzo C, Ronca R, Fiorentino G, Verra F, Mangano V, Poinsignon A, Sirima SB, Nèbiè I, Lombardo F, Remoue F, Coluzzi M, Petrarca V, Modiano D, Arcà B. Humoral response to the Anopheles gambiae salivary protein gSG6: a serological indicator of exposure to Afrotropical malaria vectors. PLoS One 2011; 6:e17980. [PMID: 21437289 PMCID: PMC3060095 DOI: 10.1371/journal.pone.0017980] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Accepted: 02/17/2011] [Indexed: 11/19/2022] Open
Abstract
Salivary proteins injected by blood feeding arthropods into their hosts evoke a saliva-specific humoral response which can be useful to evaluate exposure to bites of disease vectors. However, saliva of hematophagous arthropods is a complex cocktail of bioactive factors and its use in immunoassays can be misleading because of potential cross-reactivity to other antigens. Toward the development of a serological marker of exposure to Afrotropical malaria vectors we expressed the Anopheles gambiae gSG6, a small anopheline-specific salivary protein, and we measured the anti-gSG6 IgG response in individuals from a malaria hyperendemic area of Burkina Faso, West Africa. The gSG6 protein was immunogenic and anti-gSG6 IgG levels and/or prevalence increased in exposed individuals during the malaria transmission/rainy season. Moreover, this response dropped during the intervening low transmission/dry season, suggesting it is sensitive enough to detect variation in vector density. Members of the Fulani ethnic group showed higher anti-gSG6 IgG response as compared to Mossi, a result consistent with the stronger immune reactivity reported in this group. Remarkably, anti-gSG6 IgG levels among responders were high in children and gradually declined with age. This unusual pattern, opposite to the one observed with Plasmodium antigens, is compatible with a progressive desensitization to mosquito saliva and may be linked to the continued exposure to bites of anopheline mosquitoes. Overall, the humoral anti-gSG6 IgG response appears a reliable serological indicator of exposure to bites of the main African malaria vectors (An. gambiae, Anopheles arabiensis and, possibly, Anopheles funestus) and it may be exploited for malaria epidemiological studies, development of risk maps and evaluation of anti-vector measures. In addition, the gSG6 protein may represent a powerful model system to get a deeper understanding of molecular and cellular mechanisms underlying the immune tolerance and progressive desensitization to insect salivary allergens.
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Affiliation(s)
- Cinzia Rizzo
- Department of Public Health and Infectious Diseases, “Sapienza” University, Rome, Italy
- Istituto Pasteur - Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
| | - Raffaele Ronca
- Department of Structural and Functional Biology, “Federico II” University, Naples, Italy
| | - Gabriella Fiorentino
- Department of Structural and Functional Biology, “Federico II” University, Naples, Italy
| | - Federica Verra
- Department of Public Health and Infectious Diseases, “Sapienza” University, Rome, Italy
| | - Valentina Mangano
- Department of Public Health and Infectious Diseases, “Sapienza” University, Rome, Italy
| | - Anne Poinsignon
- UR016 Biology and Control of Vectors, Institut de Recherche pour le Développement, Montpellier, France
| | | | - Issa Nèbiè
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso
| | - Fabrizio Lombardo
- Department of Public Health and Infectious Diseases, “Sapienza” University, Rome, Italy
| | - Franck Remoue
- UR016 Biology and Control of Vectors, Institut de Recherche pour le Développement, Montpellier, France
| | - Mario Coluzzi
- Department of Public Health and Infectious Diseases, “Sapienza” University, Rome, Italy
| | - Vincenzo Petrarca
- Istituto Pasteur - Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
- Department of Biology and Biotechnology “Charles Darwin”, Sapienza University, Rome, Italy
| | - David Modiano
- Department of Public Health and Infectious Diseases, “Sapienza” University, Rome, Italy
- Istituto Pasteur - Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
| | - Bruno Arcà
- Department of Structural and Functional Biology, “Federico II” University, Naples, Italy
- * E-mail:
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Drame PM, Poinsignon A, Besnard P, Cornelie S, Le Mire J, Toto JC, Foumane V, Dos-Santos MA, Sembène M, Fortes F, Simondon F, Carnevale P, Remoue F. Human antibody responses to the Anopheles salivary gSG6-P1 peptide: a novel tool for evaluating the efficacy of ITNs in malaria vector control. PLoS One 2010; 5:e15596. [PMID: 21179476 PMCID: PMC3001874 DOI: 10.1371/journal.pone.0015596] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Accepted: 11/15/2010] [Indexed: 11/23/2022] Open
Abstract
To optimize malaria control, WHO has prioritised the need for new indicators to evaluate the efficacy of malaria vector control strategies. The gSG6-P1 peptide from gSG6 protein of Anopheles gambiae salivary glands was previously designed as a specific salivary sequence of malaria vector species. It was shown that the quantification of human antibody (Ab) responses to Anopheles salivary proteins in general and especially to the gSG6-P1 peptide was a pertinent biomarker of human exposure to Anopheles. The present objective was to validate this indicator in the evaluation of the efficacy of Insecticide Treated Nets (ITNs). A longitudinal evaluation, including parasitological, entomological and immunological assessments, was conducted on children and adults from a malaria-endemic area before and after the introduction of ITNs. Significant decrease of anti-gSG6-P1 IgG response was observed just after the efficient ITNs use. Interestingly, specific IgG Ab level was especially pertinent to evaluate a short-time period of ITNs efficacy and at individual level. However, specific IgG rose back up within four months as correct ITN use waned. IgG responses to one salivary peptide could constitute a reliable biomarker for the evaluation of ITN efficacy, at short- and long-term use, and provide a valuable tool in malaria vector control based on a real measurement of human-vector contact.
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Affiliation(s)
- Papa Makhtar Drame
- UR016 Contrôle et Caractérisation des Populations de Vecteurs, Institut de Recherche pour le Développement, Cotonou, Benin.
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Ambrosino E, Dumoulin C, Orlandi-Pradines E, Remoue F, Toure-Baldé A, Tall A, Sarr JB, Poinsignon A, Sokhna C, Puget K, Trape JF, Pascual A, Druilhe P, Fusai T, Rogier C. A multiplex assay for the simultaneous detection of antibodies against 15 Plasmodium falciparum and Anopheles gambiae saliva antigens. Malar J 2010; 9:317. [PMID: 21059211 PMCID: PMC2992071 DOI: 10.1186/1475-2875-9-317] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Accepted: 11/08/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Assessment exposure and immunity to malaria is an important step in the fight against the disease. Increased malaria infection in non-immune travellers under anti-malarial chemoprophylaxis, as well as the implementation of malaria elimination programmes in endemic countries, raises new issues that pertain to these processes. Notably, monitoring malaria immunity has become more difficult in individuals showing low antibody (Ab) responses or taking medications against the Plasmodium falciparum blood stages. Commonly available techniques in malaria seroepidemiology have limited sensitivity, both against pre-erythrocytic, as against blood stages of the parasite. Thus, the aim of this study was to develop a sensitive tool to assess the exposure to malaria or to bites from the vector Anopheles gambiae, despite anti-malarial prophylactic treatment. METHODS Ab responses to 13 pre-erythrocytic P. falciparum-specific peptides derived from the proteins Lsa1, Lsa3, Glurp, Salsa, Trap, Starp, CSP and Pf11.1, and to 2 peptides specific for the Anopheles gambiae saliva protein gSG6 were tested. In this study, 253 individuals from three Senegalese areas with different transmission intensities and 124 European travellers exposed to malaria during a short period of time were included. RESULTS The multiplex assay was optimized for most but not all of the antigens. It was rapid, reproducible and required a small volume of serum. Proportions of Ab-positive individuals, Ab levels and the mean number of antigens (Ags) recognized by each individual increased significantly with increases in the level of malaria exposure. CONCLUSION The multiplex assay developed here provides a useful tool to evaluate immune responses to multiple Ags in large populations, even when only small amounts of serum are available, or Ab titres are low, as in case of travellers. Finally, the relationship of Ab responses with malaria endemicity levels provides a way to monitor exposure in differentially exposed autochthonous individuals from various endemicity areas, as well as in travellers who are not immune, thus indirectly assessing the parasite transmission and malaria risk in the new eradication era.
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Diallo TO, Remoue F, Gaayeb L, Schacht AM, Charrier N, De Clerck D, Dompnier JP, Pillet S, Garraud O, N'Diaye AA, Riveau G. Schistosomiasis coinfection in children influences acquired immune response against Plasmodium falciparum malaria antigens. PLoS One 2010; 5:e12764. [PMID: 20856680 PMCID: PMC2939900 DOI: 10.1371/journal.pone.0012764] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Accepted: 08/03/2010] [Indexed: 11/30/2022] Open
Abstract
Background Malaria and schistosomiasis coinfection frequently occurs in tropical countries. This study evaluates the influence of Schistosoma haematobium infection on specific antibody responses and cytokine production to recombinant merozoite surface protein-1-19 (MSP1-19) and schizont extract of Plasmodium falciparum in malaria-infected children. Methodology Specific IgG1 to MSP1-19, as well as IgG1 and IgG3 to schizont extract were significantly increased in coinfected children compared to P. falciparum mono-infected children. Stimulation with MSP1-19 lead to a specific production of both interleukin-10 (IL-10) and interferon-γ (IFN-γ), whereas the stimulation with schizont extract produced an IL-10 response only in the coinfected group. Conclusions Our study suggests that schistosomiasis coinfection favours anti-malarial protective antibody responses, which could be associated with the regulation of IL-10 and IFN-γ production and seems to be antigen-dependent. This study demonstrates the importance of infectious status of the population in the evaluation of acquired immunity against malaria and highlights the consequences of a multiple infection environment during clinical trials of anti-malaria vaccine candidates.
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Wasinpiyamongkol L, Patramool S, Luplertlop N, Surasombatpattana P, Doucoure S, Mouchet F, Séveno M, Remoue F, Demettre E, Brizard JP, Jouin P, Biron DG, Thomas F, Missé D. Blood-feeding and immunogenic Aedes aegypti saliva proteins. Proteomics 2010; 10:1906-16. [PMID: 19882664 DOI: 10.1002/pmic.200900626] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Mosquito-transmitted pathogens pass through the insect's midgut (MG) and salivary gland (SG). What occurs in these organs in response to a blood meal is poorly understood, but identifying the physiological differences between sugar-fed and blood-fed (BF) mosquitoes could shed light on factors important in pathogens transmission. We compared differential protein expression in the MGs and SGs of female Aedes aegypti mosquitoes after a sugar- or blood-based diet. No difference was observed in the MG protein expression levels but certain SG proteins were highly expressed only in BF mosquitoes. In sugar-fed mosquitoes, housekeeping proteins were highly expressed (especially those related to energy metabolism) and actin was up-regulated. The immunofluorescence assay shows that there is no disruption of the SG cytoskeletal after the blood meal. We have generated for the first time the 2-DE profiles of immunogenic Ae. aegypti SG BF-related proteins. These new data could contribute to the understanding of the physiological processes that appear during the blood meal.
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Affiliation(s)
- Ladawan Wasinpiyamongkol
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
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Poinsignon A, Samb B, Doucoure S, Drame PM, Sarr JB, Sow C, Cornelie S, Maiga S, Thiam C, Rogerie F, Guindo S, Hermann E, Simondon F, Dia I, Riveau G, Konate L, Remoue F. First attempt to validate the gSG6-P1 salivary peptide as an immuno-epidemiological tool for evaluating human exposure to Anopheles funestus bites. Trop Med Int Health 2010; 15:1198-203. [PMID: 20723184 DOI: 10.1111/j.1365-3156.2010.02611.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
SUMMARY OBJECTIVE The development of a biomarker of exposure based on the evaluation of the human antibody response specific to Anopheles salivary proteins seems promising in improving malaria control. The IgG response specific to the gSG6-P1 peptide has already been validated as a biomarker of An. gambiae exposure. This study represents a first attempt to validate the gSG6-P1 peptide as an epidemiological tool evaluating exposure to An. funestus bites, the second main malaria vector in sub-Saharan Africa. METHODS A multi-disciplinary survey was performed in a Senegalese village where An. funestus represents the principal anopheline species. The IgG antibody level specific to gSG6-P1 was evaluated and compared in the same children before, at the peak and after the rainy season. RESULTS Two-thirds of the children developed a specific IgG response to gSG6-P1 during the study period and--more interestingly--before the rainy season, when An. funestus was the only anopheline species reported. The specific IgG response increased during the An. funestus exposure season, and a positive association between the IgG level and the level of exposure to An. funestus bites was observed. CONCLUSIONS The results suggest that the evaluation of the IgG response specific to gSG6-P1 in children could also represent a biomarker of exposure to An. funestus bites. The availability of such a biomarker evaluating the exposure to both main Plasmodium falciparum vectors in Africa could be particularly relevant as a direct criterion for the evaluation of the efficacy of vector control strategies.
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Affiliation(s)
- Anne Poinsignon
- Unité Caractérisation et Contrôle des Populations de Vecteurs, Institut de Recherche pour le Développement, Montpellier, France
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Drame PM, Poinsignon A, Besnard P, Le Mire J, Dos-Santos MA, Sow CS, Cornelie S, Foumane V, Toto JC, Sembene M, Boulanger D, Simondon F, Fortes F, Carnevale P, Remoue F. Human antibody response to Anopheles gambiae saliva: an immuno-epidemiological biomarker to evaluate the efficacy of insecticide-treated nets in malaria vector control. Am J Trop Med Hyg 2010; 83:115-21. [PMID: 20595489 DOI: 10.4269/ajtmh.2010.09-0684] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
For the fight against malaria, the World Health Organization (WHO) has emphasized the need for indicators to evaluate the efficacy of vector-control strategies. This study investigates a potential immunological marker, based on human antibody responses to Anopheles saliva, as a new indicator to evaluate the efficacy of insecticide-treated nets (ITNs). Parasitological, entomological, and immunological assessments were carried out in children and adults from a malaria-endemic region of Angola before and after the introduction of ITNs. Immunoglobulin G (IgG) levels to An. gambiae saliva were positively associated with the intensity of An. gambiae exposure and malaria infection. A significant decrease in the anti-saliva IgG response was observed after the introduction of ITNs, and this was associated with a drop in parasite load. This study represents the first stage in the development of a new indicator to evaluate the efficacy of malaria vector-control strategies, which could apply in other arthropod vector-borne diseases.
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Affiliation(s)
- Papa M Drame
- Institut de Recherche pour le Développement (IRD), UR024 "Epidémiologie et Prévention" Unit, Dakar, Senegal.
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Poinsignon A, Cornelie S, Ba F, Boulanger D, Sow C, Rossignol M, Sokhna C, Cisse B, Simondon F, Remoue F. Human IgG response to a salivary peptide, gSG6-P1, as a new immuno-epidemiological tool for evaluating low-level exposure to Anopheles bites. Malar J 2009; 8:198. [PMID: 19674487 PMCID: PMC2733152 DOI: 10.1186/1475-2875-8-198] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2009] [Accepted: 08/13/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Human populations exposed to low malaria transmission present particular severe risks of malaria morbidity and mortality. In addition, in a context of low-level exposure to Anopheles vector, conventional entomological methods used for sampling Anopheles populations are insufficiently sensitive and probably under-estimate the real risk of malaria transmission. The evaluation of antibody (Ab) responses to arthropod salivary proteins constitutes a novel tool for estimating exposure level to insect bites. In the case of malaria, a recent study has shown that human IgG responses to the gSG6-P1 peptide represented a specific biomarker of exposure to Anopheles gambiae bites. The objective of this study was to investigate if this biomarker can be used to estimate low-level exposure of individuals to Anopheles vector. METHODS The IgG Ab level to gSG6-P1 was evaluated at the peak and at the end of the An. gambiae exposure season in children living in Senegalese villages, where the Anopheles density was estimated to be very low by classical entomological trapping but where malaria transmission occurred during the studied season. RESULTS Specific IgG responses to gSG6-P1 were observed in children exposed to very low-level of Anopheles bites. In addition, a significant increase in the specific IgG Ab level was observed during the Anopheles exposure season whereas classical entomological data have reported very few or no Anopheles during the studied period. Furthermore, this biomarker may also be applicable to evaluate the heterogeneity of individual exposure. CONCLUSION The results strengthen the hypothesis that the evaluation of IgG responses to gSG6-P1 during the season of exposure could reflect the real human contact with anthropophilic Anopheles and suggest that this biomarker of low exposure could be used at the individual level. This promising immuno-epidemiological marker could represent a useful tool to assess the risk to very low exposure to malaria vectors as observed in seasonal, urban, altitude or travellers contexts. In addition, this biomarker could be used for the surveillance survey after applying anti-vector strategy.
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Affiliation(s)
- Anne Poinsignon
- UR016-IRD (Institut de Recherche pour le Développement), Caractérisation et Contrôle des Populations de Vecteurs, 911 avenue Agropolis, BP 64501, 34394 Montpellier Cedex 5, France
| | - Sylvie Cornelie
- UR016-IRD (Institut de Recherche pour le Développement), Caractérisation et Contrôle des Populations de Vecteurs, 911 avenue Agropolis, BP 64501, 34394 Montpellier Cedex 5, France
| | - Fatou Ba
- UR077-IRD, Campus International IRD-UCAD, route des Pères Maristes, BP 1836, Dakar, Sénégal
| | - Denis Boulanger
- UR024-IRD, Montpellier, France and Campus International IRD-UCAD, Dakar, Sénégal
| | - Cheikh Sow
- UR024-IRD, Montpellier, France and Campus International IRD-UCAD, Dakar, Sénégal
| | - Marie Rossignol
- UR016-IRD (Institut de Recherche pour le Développement), Caractérisation et Contrôle des Populations de Vecteurs, 911 avenue Agropolis, BP 64501, 34394 Montpellier Cedex 5, France
| | - Cheikh Sokhna
- UR077-IRD, Campus International IRD-UCAD, route des Pères Maristes, BP 1836, Dakar, Sénégal
| | - Badara Cisse
- Département de parasitologie, Université Cheikh Anta Diop, Dakar, Sénégal
| | - François Simondon
- UR024-IRD, Montpellier, France and Campus International IRD-UCAD, Dakar, Sénégal
| | - Franck Remoue
- UR016-IRD (Institut de Recherche pour le Développement), Caractérisation et Contrôle des Populations de Vecteurs, 911 avenue Agropolis, BP 64501, 34394 Montpellier Cedex 5, France
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Poinsignon A, Cornelie S, Mestres-Simon M, Lanfrancotti A, Rossignol M, Boulanger D, Cisse B, Sokhna C, Arcà B, Simondon F, Remoue F. Novel peptide marker corresponding to salivary protein gSG6 potentially identifies exposure to Anopheles bites. PLoS One 2008; 3:e2472. [PMID: 18575604 PMCID: PMC2427200 DOI: 10.1371/journal.pone.0002472] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Accepted: 04/30/2008] [Indexed: 11/18/2022] Open
Abstract
Background In order to improve malaria control, and under the aegis of WHO recommendations, many efforts are being devoted to developing new tools for identifying geographic areas with high risk of parasite transmission. Evaluation of the human antibody response to arthropod salivary proteins could be an epidemiological indicator of exposure to vector bites, and therefore to risk of pathogen transmission. In the case of malaria, which is transmitted only by anopheline mosquitoes, maximal specificity could be achieved through identification of immunogenic proteins specific to the Anopheles genus. The objective of the present study was to determine whether the IgG response to the Anopheles gambiae gSG6 protein, from its recombinant form to derived synthetic peptides, could be an immunological marker of exposure specific to Anopheles gambiae bites. Methodology/Principal Findings Specific IgG antibodies to recombinant gSG6 protein were observed in children living in a Senegalese area exposed to malaria. With the objective of optimizing Anopheles specificity and reproducibility, we designed five gSG6-based peptide sequences using a bioinformatic approach, taking into consideration i) their potential antigenic properties and ii) the absence of cross-reactivity with protein sequences of other arthropods/organisms. The specific anti-peptide IgG antibody response was evaluated in exposed children. The five gSG6 peptides showed differing antigenic properties, with gSG6-P1 and gSG6-P2 exhibiting the highest antigenicity. However, a significant increase in the specific IgG response during the rainy season and a positive association between the IgG level and the level of exposure to Anopheles gambiae bites was significant only for gSG6-P1. Conclusions/Significance This step-by-step approach suggests that gSG6-P1 could be an optimal candidate marker for evaluating exposure to Anopheles gambiae bites. This marker could be employed as a geographic indicator, like remote sensing techniques, for mapping the risk of malaria. It could also represent a direct criterion of efficacy in evaluation of vector control strategies.
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Affiliation(s)
- Anne Poinsignon
- UR024-Epidémiologie et Prévention, Institut de Recherche pour le Développement, Dakar, Sénégal.
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Poinsignon A, Rossignol M, Cornelie S, Grébaut P, Courtin D, Garcia A, Simondon F, Remoue F. Human IgG Antibody Response to Glossina Saliva: An Epidemiologic Marker of Exposure to Glossina Bites. Am J Trop Med Hyg 2008. [DOI: 10.4269/ajtmh.2008.78.750] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Poinsignon A, Remoue F, Rossignol M, Cornelie S, Courtin D, Grébaut P, Garcia A, Simondon F. Human IgG antibody response to Glossina saliva: an epidemiologic marker of exposure to Glossina bites. Am J Trop Med Hyg 2008; 78:750-753. [PMID: 18458309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
The evaluation of human antibody response specific to arthropod saliva may be a useful marker of exposure to vector-borne disease. Such an immunologic tool, applied to the evaluation of the exposure to Glossina bites, could be integrated in the control of human African trypanosomiasis (HAT). The antibody (IgG) response specific to uninfected Glossina fuscipes fuscipes saliva was evaluated according to the vector exposure and trypanic status in individuals residing in an HAT-endemic area. A high level of anti-saliva IgG antibodies was only detected in exposed individuals, whether infected or not by Trypanosoma brucei gambiense. In addition, the evaluation of specific IgG response represented spatial heterogeneity according to studied sites. These results suggest that the evaluation of anti-saliva IgG could be an indicator of Glossina exposure and thus could be integrated in other available tools to identify populations presenting risks of HAT transmission.
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Affiliation(s)
- Anne Poinsignon
- Epidémiologie et Prévention, Institut de Recherche pour le Développement, Dakar, Sénégal.
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