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Nguetsa GC, Elanga-Ndille E, Essangui Same EG, Nganso Keptchouang T, Mandeng SE, Ekoko Eyisap W, Binyang JA, Fogang B, Nouage L, Piameu M, Ayong L, Etang J, Wanji S, Eboumbou Moukoko CE. Utility of plasma anti-gSG6-P1 IgG levels in determining changes in Anopheles gambiae bite rates in a rural area of Cameroon. Sci Rep 2024; 14:14294. [PMID: 38906949 PMCID: PMC11192751 DOI: 10.1038/s41598-024-58337-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 03/27/2024] [Indexed: 06/23/2024] Open
Abstract
The applicability of the specific human IgG antibody response to Anopheles gambiae salivary Gland Protein-6 peptide 1 (gSG6-P1 salivary peptide) as a biomarker able to distinguish the level of exposure to mosquito bites according to seasonal variations has not yet been evaluated in Central African regions. The study aimed to provide the first reliable data on the IgG anti-gSG6-P1 response in rural area in Cameroon according to the dry- and rainy-season. Between May and December 2020, dry blood samples were collected from people living in the Bankeng village in the forest area of the Centre region of Cameroon. Malaria infection was determined by thick-blood smear microscopy and multiplex PCR. The level of IgG anti-gSG6-P1 response, was assessed by enzyme-linked immunosorbent assay. Anopheles density and aggressiveness were assessed using human landing catches. The prevalence of malaria infection remains significantly higher in the rainy season than in the dry season (77.57% vs 61.44%; p = 0.0001). The specific anti-gSG6-P1 IgG response could be detected in individuals exposed to few mosquito bites and showed inter-individual heterogeneity even when living in the same exposure area. In both seasons, the level of anti-gSG6-P1 IgG response was not significantly different between Plasmodium infected and non-infected individuals. Mosquito bites were more aggressive in the rainy season compared to the dry season (human biting rate-HBR of 15.05 b/p/n vs 1.5 b/p/n) where mosquito density was very low. Infected mosquitoes were found only during the rainy season (sporozoite rate = 10.63% and entomological inoculation rate-EIR = 1.42 ib/p/n). The level of IgG anti-gSG6-P1 response was significantly higher in the rainy season and correlated with HBR (p ˂ 0.0001). This study highlights the high heterogeneity of individual's exposure to the Anopheles gambiae s.l vector bites depending on the transmission season in the same area. These findings reinforce the usefulness of the anti-gSG6-P1 IgG response as an accurate immunological biomarker for detecting individual exposure to Anopheles gambiae s.l. bites during the low risk period of malaria transmission in rural areas and for the differentiating the level of exposure to mosquitoes.
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Affiliation(s)
- Glwadys Cheteug Nguetsa
- Malaria Research Unit, Centre Pasteur Cameroon, P.O. Box 1274, Yaoundé, Cameroon.
- Department of Microbiology and Parasitology, Faculty of Sciences, The University of Buea, P.O. Box 63, Buea, Cameroon.
| | - Emmanuel Elanga-Ndille
- Department of Animal Biology, Faculty of Sciences, The University of Dschang, P.O. Box 96, Dschang, Cameroon
- Department of Medical Entomology, Centre for Research in Infectious Diseases, P.O. Box 13591, Yaoundé, Cameroon
| | - Estelle Géraldine Essangui Same
- Malaria Research Unit, Centre Pasteur Cameroon, P.O. Box 1274, Yaoundé, Cameroon
- Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, The University of Douala, P.O. Box 2701, Douala, Cameroon
| | - Tatiana Nganso Keptchouang
- Malaria Research Unit, Centre Pasteur Cameroon, P.O. Box 1274, Yaoundé, Cameroon
- Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, The University of Douala, P.O. Box 2701, Douala, Cameroon
| | - Stanilas Elysée Mandeng
- Department of Animal Biology and Physiology, Faculty of Sciences, The University of Yaoundé, P.O. Box 337, Yaounde 1, Cameroon
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon
| | - Wolfgang Ekoko Eyisap
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon
| | - Jérome Achille Binyang
- Department of Medical Entomology, Centre for Research in Infectious Diseases, P.O. Box 13591, Yaoundé, Cameroon
- Department of Animal Biology and Physiology, Faculty of Sciences, The University of Yaoundé, P.O. Box 337, Yaounde 1, Cameroon
| | - Balotin Fogang
- Malaria Research Unit, Centre Pasteur Cameroon, P.O. Box 1274, Yaoundé, Cameroon
- Department of Animal Biology and Physiology, Faculty of Sciences, The University of Yaoundé, P.O. Box 337, Yaounde 1, Cameroon
| | - Lynda Nouage
- Department of Medical Entomology, Centre for Research in Infectious Diseases, P.O. Box 13591, Yaoundé, Cameroon
- Department of Animal Biology and Physiology, Faculty of Sciences, The University of Yaoundé, P.O. Box 337, Yaounde 1, Cameroon
| | - Micheal Piameu
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon
- Ecole des Sciences de La Santé, Université Catholique d'Afrique Centrale, P.O. Box 1110, Yaoundé, Cameroon
| | - Lawrence Ayong
- Malaria Research Unit, Centre Pasteur Cameroon, P.O. Box 1274, Yaoundé, Cameroon
| | - Josiane Etang
- Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, The University of Douala, P.O. Box 2701, Douala, Cameroon
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon
| | - Samuel Wanji
- Department of Microbiology and Parasitology, Faculty of Sciences, The University of Buea, P.O. Box 63, Buea, Cameroon
| | - Carole Else Eboumbou Moukoko
- Malaria Research Unit, Centre Pasteur Cameroon, P.O. Box 1274, Yaoundé, Cameroon.
- Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, The University of Douala, P.O. Box 2701, Douala, Cameroon.
- Laboratory of Parasitology, Mycology and Virology, Postgraduate Training Unit for Health Sciences, Postgraduate School for Pure and Applied Sciences, The University of Douala, P.O. Box 2701, Douala, Cameroon.
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Asare KK, Agrah B, Ofori-Acquah FS, Kudzi W, Aryee NA, Amoah LE. Immune responses to P falciparum antibodies in symptomatic malaria patients with variant hemoglobin genotypes in Ghana. BMC Immunol 2024; 25:14. [PMID: 38336647 PMCID: PMC10858493 DOI: 10.1186/s12865-024-00607-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 02/02/2024] [Indexed: 02/12/2024] Open
Abstract
BACKGROUND Haemoglobin (Hb) variants such as sickle cell trait (SCT/HbAS) play a role in protecting against clinical malaria, but little is known about the development of immune responses against malaria parasite (Plasmodium falciparum surface protein 230 (Pfs230) and Plasmodium falciparum erythrocyte binding antigen 175 region-3 (PfEBA175-3R)) and vector (on the An. gambiae Salivary Gland Protein-6 peptide 1 (gSG6-P1)) antigens in individuals with variants Hb genotypes. This study assessed antibody (IgG) responses against malaria parasite, Pfs230 and PfEBA175-3R and vector, gSG6-P1 in febrile individuals with variant Hb genotypes. METHODS The study was conducted on symptomatic malaria patients attending various healthcare facilities throughout Ghana. Microscopy and ELISA were used to determine the natural IgG antibody levels of gSG6-P1, PfEBA175-3R & Pfs230, and Capillarys 2 Flex Piercing was used for Hb variants determination. RESULTS Of the 600 symptomatic malaria patients, 50.0% of the participants had malaria parasites by microscopy. The majority 79.0% (398/504) of the participants had Hb AA, followed by HbAS variant at 11.3% (57/504) and HbAC 6.7% (34/504). There were significantly (p < 0.0001) reduced levels of gSG6-P1 IgG in individuals with both HbAC and HbAS genotypes compared to the HbAA genotype. The levels of gSG6-P1 IgG were significantly (p < 0.0001) higher in HbAS compared to HbAC. Similarly, Pfs230 IgG and PfEBA-175-3R IgG distributions observed across the haemoglobin variants were significantly higher in HbAC relative to HbAS. CONCLUSION The study has shown that haemoglobin variants significantly influence the pattern of anti-gSG6-P1, Pfs230, and PfEBA-175 IgG levels in malaria-endemic population. The HbAS genotype is suggested to confer protection against malaria infection. Reduced exposure to infection ultimately reduces the induction of antibodies targeted against P. falciparum antigens.
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Affiliation(s)
- Kwame Kumi Asare
- Department of Biomedical Science, School of Allied Health Sciences, University of Cape Coast, Cape Coast, Ghana
- Biomedical and Clinical Research Centre, College of Allied Health Sciences, University of Cape Coast, Cape Coast, Ghana
| | - Benjamin Agrah
- Department of Medical Biochemistry, College of Health Sciences, University of Ghana Medical School, University of Ghana, Korle- Bu, Accra, Ghana
| | | | - William Kudzi
- West Africa Genetic Medicine Centre, University of Ghana, Accra, Ghana
| | - Nii Ayite Aryee
- Department of Medical Biochemistry, College of Health Sciences, University of Ghana Medical School, University of Ghana, Korle- Bu, Accra, Ghana
| | - Linda Eva Amoah
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana.
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IgG antibody responses to Anopheles gambiae gSG6-P1 salivary peptide are induced in human populations exposed to secondary malaria vectors in forest areas in Cameroon. PLoS One 2022; 17:e0276991. [PMID: 36355922 PMCID: PMC9648791 DOI: 10.1371/journal.pone.0276991] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 10/18/2022] [Indexed: 11/12/2022] Open
Abstract
Human IgG antibody response to Anopheles gambiae gSG6-P1 salivary peptide was reported to be a pertinent indicator for assessing human exposure to mosquito bites and evaluating the risk of malaria transmission as well as the effectiveness of vector control strategies. However, the applicability of this marker to measure malaria transmission risk where human populations are mostly bitten by secondary vectors in Africa has not yet been evaluated. In this study, we aimed to investigate whether anti-gSG6-P1 antibodies response could be induced in humans living in forest areas in Cameroon where An. gambiae s.l is not predominant. In October 2019 at the pick of the rainy season, blood samples were collected from people living in the Nyabessang in the forest area in the South region of Cameroon. Malaria infection was determined using thick blood smear microscopy and Rapid Diagnostic Test. The level of IgG Anti-gSG6-P1 response as a biomarker of human exposure to Anopheles bite, was assessed using enzyme-linked immunosorbent assay. Mosquitoes were collected using the human landing catches to assess Anopheles density and for the identification of Anopheles species present in that area. IgG antibody response to the gSG6-P1 salivary peptide was detected in inhabitants of Nyabessang with high inter-individual heterogeneity. No significant variation in the level of this immune response was observed according to age and gender. The concentration of gSG6-P1 antibodies was significantly correlated with the malaria infection status and, Plasmodium falciparum-infected individuals presented a significantly higher level of IgG response than uninfected individuals (p = 0.0087). No significant difference was observed according to the use of insecticide treated nets. Out of the 1,442 Anopheles mosquitoes species collected, 849 (58.9%) were identified as An. paludis, 489 (33.91%) as An. moucheti, 28 (4.44%) as An. nili, 22 (2.08%) as An. gambiae s.l and 10 (0.69%) as An. marshallii. Our findings show that IgG response to An. gambiae gSG6-P1 peptide could be detected in humans exposed predominantly to An. moucheti and An. paludis bites. Taken together, the data revealed the potential of the Anti-gSG6-P1 IgG antibody response to serve as a universal marker to assess human exposure to any Anopheles species.
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Olajiga OM, Marin-Lopez A, Cardenas JC, Gutierrez-Silva LY, Gonzales-Pabon MU, Maldonado-Ruiz LP, Worges M, Fikrig E, Park Y, Londono-Renteria B. Aedes aegypti anti-salivary proteins IgG levels in a cohort of DENV-like symptoms subjects from a dengue-endemic region in Colombia. FRONTIERS IN EPIDEMIOLOGY 2022; 2:1002857. [PMID: 38455331 PMCID: PMC10910902 DOI: 10.3389/fepid.2022.1002857] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 10/20/2022] [Indexed: 03/09/2024]
Abstract
Dengue fever, caused by the dengue virus (DENV), is currently a threat to about half of the world's population. DENV is mainly transmitted to the vertebrate host through the bite of a female Aedes mosquito while taking a blood meal. During this process, salivary proteins are introduced into the host skin and blood to facilitate blood acquisition. These salivary proteins modulate both local (skin) and systemic immune responses. Several salivary proteins have been identified as immunogenic inducing the production of antibodies with some of those proteins also displaying immunomodulatory properties enhancing arboviral infections. IgG antibody responses against salivary gland extracts of a diverse number of mosquitoes, as well as antibody responses against the Ae. aegypti peptide, Nterm-34 kDa, have been suggested as biomarkers of human exposure to mosquito bites while antibodies against AgBR1 and NeSt1 proteins have been investigated for their potential protective effect against Zika virus (ZIKV) and West Nile virus infections. Thus, we were interested in evaluating whether IgG antibodies against AgBR1, NeSt1, Nterm-34 kDa peptide, and SGE were associated with DENV infections and clinical characteristics. For this, we tested samples from volunteers living in a dengue fever endemic area in Colombia in 2019 for the presence of IgG antibodies against those salivary proteins and peptides using an ELISA test. Results from this pilot study suggest an involvement of antibody responses against salivary proteins in dengue disease progression.
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Affiliation(s)
- Olayinka M. Olajiga
- Department of Entomology, Kansas State University, Manhattan, KS, United States
| | - Alejandro Marin-Lopez
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Jenny C. Cardenas
- Laboratorio Clínico, Hospital Local Los Patios, Los Patios, Colombia
| | | | | | | | - Matt Worges
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University of New Orleans, New Orleans, LA, United States
| | - Erol Fikrig
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Yoonseong Park
- Department of Entomology, Kansas State University, Manhattan, KS, United States
| | - Berlin Londono-Renteria
- Department of Entomology, Kansas State University, Manhattan, KS, United States
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University of New Orleans, New Orleans, LA, United States
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Building an integrated serosurveillance platform to inform public health interventions: Insights from an experts' meeting on serum biomarkers. PLoS Negl Trop Dis 2022; 16:e0010657. [PMID: 36201428 PMCID: PMC9536637 DOI: 10.1371/journal.pntd.0010657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The use of biomarkers to measure immune responses in serum is crucial for understanding population-level exposure and susceptibility to human pathogens. Advances in sample collection, multiplex testing, and computational modeling are transforming serosurveillance into a powerful tool for public health program design and response to infectious threats. In July 2018, 70 scientists from 16 countries met to perform a landscape analysis of approaches that support an integrated serosurveillance platform, including the consideration of issues for successful implementation. Here, we summarize the group's insights and proposed roadmap for implementation, including objectives, technical requirements, ethical issues, logistical considerations, and monitoring and evaluation.
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Barillas-Mury C, Ribeiro JMC, Valenzuela JG. Understanding pathogen survival and transmission by arthropod vectors to prevent human disease. Science 2022; 377:eabc2757. [PMID: 36173836 DOI: 10.1126/science.abc2757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Many endemic poverty-associated diseases, such as malaria and leishmaniasis, are transmitted by arthropod vectors. Pathogens must interact with specific molecules in the vector gut, the microbiota, and the vector immune system to survive and be transmitted. The vertebrate host, in turn, is infected when the pathogen and vector-derived factors, such as salivary proteins, are delivered into the skin by a vector bite. Here, we review recent progress in our understanding of the biology of pathogen transmission from the human to the vector and back, from the vector to the host. We also highlight recent advances in the biology of vector-borne disease transmission, which have translated into additional strategies to prevent human disease by either reducing vector populations or by disrupting their ability to transmit pathogens.
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Affiliation(s)
- Carolina Barillas-Mury
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, MD 20852, USA
| | - José M C Ribeiro
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, MD 20852, USA
| | - Jesus G Valenzuela
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, MD 20852, USA
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Somda MB, N'Djetchi MK, Kaboré J, Ilboudo H, Dama E, Boma S, Courtin F, Poinsignon A, Bengaly Z, Remoué F, Belem AMG, Bucheton B, Jamonneau V, Koffi M. Evaluation of antibody responses to tsetse fly saliva in domestic animals in the sleeping sickness endemic foci of Bonon and Sinfra, Côte d'Ivoire. Vet Parasitol Reg Stud Reports 2022; 34:100773. [PMID: 36041808 DOI: 10.1016/j.vprsr.2022.100773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 07/19/2022] [Accepted: 08/01/2022] [Indexed: 06/15/2023]
Abstract
After intensive control efforts, human African trypanosomiasis (HAT) was declared eliminated in Côte d'Ivoire as a public health problem in December 2020 and the current objective is to achieve the interruption of the transmission (zero cases). Reaching this objective could be hindered by the existence of an animal reservoir of Trypanosoma (T.) brucei (b.) gambiense. In the framework of a study led in 2013 to assess the role of domestic animals in the epidemiology of HAT in the two last active foci from Côte d'Ivoire (Bonon and Sinfra), plasmas were sampled from four species of domestic animals for parasitological (microscopic examination by the buffy coat technique (BCT)), serological (immune trypanolysis (TL)) and molecular (specific PCR: TBR for T. brucei s.l., TCF for T. congolense forest type, TVW for T. vivax and PCR for T. b. gambiense) testing. In order to improve the understanding of the involvement/role of these animals in the transmission of T. b. gambiense, we have quantified in this study the IgG response to whole saliva extracts of Glossina palpalis gambiensis in order to perform an association analysis between anti-saliva responses and the positivity of diagnostic tests. Cattle and pigs had significantly higher rates of anti-tsetse saliva responses compared to goats and sheep (p < 0.01). In addition, the anti-tsetse saliva responses were strongly associated with the parasitology (BCT+), serology (TL+) and PCR (TBR+ and TCF+) results (p < 0.001). These associations indicate a high level of contacts between the positive/infected animals and tsetse flies. Our findings suggest that protecting cattle and pigs against tsetse bites could have a significant impact in reducing transmission of both animal and human trypanosome species, and advocates for a "One health" approach to better control African trypanosomosis in Côte d'Ivoire.
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Affiliation(s)
- Martin Bienvenu Somda
- Université Nazi BONI (UNB), Laboratoire de santé animale tropicale (LASANTROP), 01 BP 1 091 Bobo-Dioulasso 01, Burkina Faso; Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Unité de Recherche «maladies à vecteurs et biodiversité (UMaVeB)», 01 BP 454 Bobo-Dioulasso 01, Burkina Faso.
| | - Martial Kassi N'Djetchi
- Université Jean Lorougnon Guédé (UJLoG), Unité de Formation et de Recherche Environnement, Laboratoire des Interactions Hôte-Microorganisme-Environnement et Evolution, BP 150 Daloa, Côte d'Ivoire
| | - Jacques Kaboré
- Université Nazi BONI (UNB), Laboratoire de santé animale tropicale (LASANTROP), 01 BP 1 091 Bobo-Dioulasso 01, Burkina Faso; Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Unité de Recherche «maladies à vecteurs et biodiversité (UMaVeB)», 01 BP 454 Bobo-Dioulasso 01, Burkina Faso
| | - Hamidou Ilboudo
- Institut de Recherche en Sciences de la Santé (IRSS), Unité de Recherche Clinique de Nanoro (URCN), 11 BP 218 Ouagadougou CMS 11, Burkina Faso
| | - Emilie Dama
- Université Nazi BONI (UNB), Laboratoire de santé animale tropicale (LASANTROP), 01 BP 1 091 Bobo-Dioulasso 01, Burkina Faso
| | - Soudah Boma
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Unité de Recherche «maladies à vecteurs et biodiversité (UMaVeB)», 01 BP 454 Bobo-Dioulasso 01, Burkina Faso
| | - Fabrice Courtin
- Institut de Recherche pour le Développement (IRD), Université de Montpellier, Unité Mixte de Recherche 177 INTERTRYP IRD-CIRAD, 34398 Montpellier, France
| | - Anne Poinsignon
- MIVEGEC (Maladies Infectieuses et Vecteurs : Écologie, Génétique, Évolution et Contrôle), University of Montpellier, IRD, CNRS, Montpellier, France
| | - Zakaria Bengaly
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Unité de Recherche «maladies à vecteurs et biodiversité (UMaVeB)», 01 BP 454 Bobo-Dioulasso 01, Burkina Faso
| | - Franck Remoué
- MIVEGEC (Maladies Infectieuses et Vecteurs : Écologie, Génétique, Évolution et Contrôle), University of Montpellier, IRD, CNRS, Montpellier, France
| | - Adrien Marie Gaston Belem
- Université Nazi BONI (UNB), Laboratoire de santé animale tropicale (LASANTROP), 01 BP 1 091 Bobo-Dioulasso 01, Burkina Faso
| | - Bruno Bucheton
- Institut de Recherche pour le Développement (IRD), Université de Montpellier, Unité Mixte de Recherche 177 INTERTRYP IRD-CIRAD, 34398 Montpellier, France
| | - Vincent Jamonneau
- Institut de Recherche pour le Développement (IRD), Université de Montpellier, Unité Mixte de Recherche 177 INTERTRYP IRD-CIRAD, 34398 Montpellier, France
| | - Mathurin Koffi
- Institut de Recherche en Sciences de la Santé (IRSS), Unité de Recherche Clinique de Nanoro (URCN), 11 BP 218 Ouagadougou CMS 11, Burkina Faso
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Willen L, Milton P, Hamley JID, Walker M, Osei-Atweneboana MY, Volf P, Basáñez MG, Courtenay O. Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites. PLoS Negl Trop Dis 2022; 16:e0010108. [PMID: 35020729 PMCID: PMC8789114 DOI: 10.1371/journal.pntd.0010108] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 01/25/2022] [Accepted: 12/17/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND In onchocerciasis endemic areas in Africa, heterogenous biting rates by blackfly vectors on humans are assumed to partially explain age- and sex-dependent infection patterns with Onchocerca volvulus. To underpin these assumptions and further improve predictions made by onchocerciasis transmission models, demographic patterns in antibody responses to salivary antigens of Simulium damnosum s.l. are evaluated as a measure of blackfly exposure. METHODOLOGY/PRINCIPAL FINDINGS Recently developed IgG and IgM anti-saliva immunoassays for S. damnosum s.l. were applied to blood samples collected from residents in four onchocerciasis endemic villages in Ghana. Demographic patterns in antibody levels according to village, sex and age were explored by fitting generalized linear models. Antibody levels varied between villages but showed consistent patterns with age and sex. Both IgG and IgM responses declined with increasing age. IgG responses were generally lower in males than in females and exhibited a steeper decline in adult males than in adult females. No sex-specific difference was observed in IgM responses. CONCLUSIONS/SIGNIFICANCE The decline in age-specific antibody patterns suggested development of immunotolerance or desensitization to blackfly saliva antigen in response to persistent exposure. The variation between sexes, and between adults and youngsters may reflect differences in behaviour influencing cumulative exposure. These measures of antibody acquisition and decay could be incorporated into onchocerciasis transmission models towards informing onchocerciasis control, elimination, and surveillance.
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Affiliation(s)
- Laura Willen
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
- Centre for the Evaluation of Vaccinations, Vaccine and Infectious Disease Institute, University of Antwerp, Wilrijk, Belgium
- * E-mail: (LW); (OC)
| | - Philip Milton
- MRC Centre for Global Infectious Disease Analysis and London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom
| | - Jonathan I. D. Hamley
- MRC Centre for Global Infectious Disease Analysis and London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom
| | - Martin Walker
- London Centre for Neglected Tropical Disease Research and Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, United Kingdom
| | | | - Petr Volf
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Maria-Gloria Basáñez
- MRC Centre for Global Infectious Disease Analysis and London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom
| | - Orin Courtenay
- Zeeman Institute for Systems Biology & Infectious Disease Epidemiology Research and School of Life Sciences, University of Warwick, Coventry, United Kingdom
- * E-mail: (LW); (OC)
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Oseno B, Marura F, Ogwang R, Muturi M, Njunge J, Nkumama I, Mwakesi R, Mwai K, Rono MK, Mwakubambanya R, Osier F, Tuju J. Characterization of Anopheles gambiae D7 salivary proteins as markers of human-mosquito bite contact. Parasit Vectors 2022; 15:11. [PMID: 34996508 PMCID: PMC8742437 DOI: 10.1186/s13071-021-05130-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 12/11/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria is transmitted when infected Anopheles mosquitoes take a blood meal. During this process, the mosquitoes inject a cocktail of bioactive proteins that elicit antibody responses in humans and could be used as biomarkers of exposure to mosquito bites. This study evaluated the utility of IgG responses to members of the Anopheles gambiae D7 protein family as serological markers of human-vector contact. METHODS The D7L2, D7r1, D7r2, D7r3, D7r4 and SG6 salivary proteins from An. gambiae were expressed as recombinant antigens in Escherichia coli. Antibody responses to the salivary proteins were compared in Europeans with no prior exposure to malaria and lifelong residents of Junju in Kenya and Kitgum in Uganda where the intensity of malaria transmission is moderate and high, respectively. In addition, to evaluate the feasibility of using anti-D7 IgG responses as a tool to evaluate the impact of vector control interventions, we compared responses between individuals using insecticide-treated bednets to those who did not in Junju, Kenya where bednet data were available. RESULTS We show that both the long and short forms of the D7 salivary gland antigens elicit a strong antibody response in humans. IgG responses against the D7 antigens reflected the transmission intensities of the three study areas, with the highest to lowest responses observed in Kitgum (northern Uganda), Junju (Kenya) and malaria-naïve Europeans, respectively. Specifically, the long form D7L2 induced an IgG antibody response that increased with age and that was lower in individuals who slept under a bednet, indicating its potential as a serological tool for estimating human-vector contact and monitoring the effectiveness of vector control interventions. CONCLUSIONS This study reveals that D7L2 salivary antigen has great potential as a biomarker of exposure to mosquito bites and as a tool for assessing the efficacy of vector control strategies such as bednet use.
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Affiliation(s)
- Brenda Oseno
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya.,Egerton University, P.O. Box 536-20115, Nakuru, Kenya
| | - Faith Marura
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya
| | - Rodney Ogwang
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya
| | - Martha Muturi
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya
| | - James Njunge
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya
| | - Irene Nkumama
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya.,Heidelberg University Hospital, Neuenheimer Feld, 672 69120, Heidelberg, Germany
| | - Robert Mwakesi
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya
| | - Kennedy Mwai
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya.,School of Public Health, University of the Witwatersrand, 1 Jan Smuts Avenue, Braamfontein 2000, Johannesburg, South Africa
| | - Martin K Rono
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya.,Pwani University, P.O. Box 195-80108, Kilifi, Kenya
| | | | - Faith Osier
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya.,Pwani University, P.O. Box 195-80108, Kilifi, Kenya.,Heidelberg University Hospital, Neuenheimer Feld, 672 69120, Heidelberg, Germany
| | - James Tuju
- KEMRI-Wellcome Trust Research Programme CGMRC, P.O. Box 230-80108, Kilifi, Kenya. .,Pwani University, P.O. Box 195-80108, Kilifi, Kenya.
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10
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Kearney EA, Agius PA, Chaumeau V, Cutts JC, Simpson JA, Fowkes FJI. Anopheles salivary antigens as serological biomarkers of vector exposure and malaria transmission: A systematic review with multilevel modelling. eLife 2021; 10:e73080. [PMID: 34939933 PMCID: PMC8860437 DOI: 10.7554/elife.73080] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 12/21/2021] [Indexed: 12/25/2022] Open
Abstract
Background Entomological surveillance for malaria is inherently resource-intensive and produces crude population-level measures of vector exposure which are insensitive in low-transmission settings. Antibodies against Anopheles salivary proteins measured at the individual level may serve as proxy biomarkers for vector exposure and malaria transmission, but their relationship is yet to be quantified. Methods A systematic review of studies measuring antibodies against Anopheles salivary antigens (PROSPERO: CRD42020185449). Multilevel modelling (to account for multiple study-specific observations [level 1], nested within study [level 2], and study nested within country [level 3]) estimated associations between seroprevalence with Anopheles human biting rate (HBR) and malaria transmission measures. Results From 3981 studies identified in literature searches, 42 studies across 16 countries were included contributing 393 study-specific observations of anti-Anopheles salivary antibodies determined in 42,764 samples. A positive association between HBR (log transformed) and seroprevalence was found; overall a twofold (100% relative) increase in HBR was associated with a 23% increase in odds of seropositivity (OR: 1.23, 95% CI: 1.10-1.37; p<0.001). The association between HBR and Anopheles salivary antibodies was strongest with concordant, rather than discordant, Anopheles species. Seroprevalence was also significantly positively associated with established epidemiological measures of malaria transmission: entomological inoculation rate, Plasmodium spp. prevalence, and malarial endemicity class. Conclusions Anopheles salivary antibody biomarkers can serve as a proxy measure for HBR and malaria transmission, and could monitor malaria receptivity of a population to sustain malaria transmission. Validation of Anopheles species-specific biomarkers is important given the global heterogeneity in the distribution of Anopheles species. Salivary biomarkers have the potential to transform surveillance by replacing impractical, inaccurate entomological investigations, especially in areas progressing towards malaria elimination. Funding Australian National Health and Medical Research Council, Wellcome Trust.
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Affiliation(s)
- Ellen A Kearney
- The McFarlane Burnet Institute of Medical Research and Public HealthMelbourneAustralia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of MelbourneMelbourneAustralia
| | - Paul A Agius
- The McFarlane Burnet Institute of Medical Research and Public HealthMelbourneAustralia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of MelbourneMelbourneAustralia
- Department of Epidemiology and Preventive Medicine, Monash UniversityMelbourneAustralia
| | - Victor Chaumeau
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol UniversityMae SotThailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
| | - Julia C Cutts
- The McFarlane Burnet Institute of Medical Research and Public HealthMelbourneAustralia
- Department of Medicine at the Doherty Institute, The University of MelbourneMelbourneAustralia
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of MelbourneMelbourneAustralia
| | - Freya JI Fowkes
- The McFarlane Burnet Institute of Medical Research and Public HealthMelbourneAustralia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of MelbourneMelbourneAustralia
- Department of Epidemiology and Preventive Medicine, Monash UniversityMelbourneAustralia
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11
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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] [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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12
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Human immune response against salivary antigens of Simulium damnosum s.l.: A new epidemiological marker for exposure to blackfly bites in onchocerciasis endemic areas. PLoS Negl Trop Dis 2021; 15:e0009512. [PMID: 34157020 PMCID: PMC8253393 DOI: 10.1371/journal.pntd.0009512] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 07/02/2021] [Accepted: 05/27/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Simulium damnosum sensu lato (s.l.) blackflies transmit Onchocerca volvulus, a filarial nematode that causes human onchocerciasis. Human landing catches (HLCs) is currently the sole method used to estimate blackfly biting rates but is labour-intensive and questionable on ethical grounds. A potential alternative is to measure host antibodies to vector saliva deposited during bloodfeeding. In this study, immunoassays to quantify human antibody responses to S. damnosum s.l. saliva were developed, and the salivary proteome of S. damnosum s.l. was investigated. METHODOLOGY/PRINCIPAL FINDINGS Blood samples from people living in onchocerciasis-endemic areas in Ghana were collected during the wet season; samples from people living in Accra, a blackfly-free area, were considered negative controls and compared to samples from blackfly-free locations in Sudan. Blackflies were collected by HLCs and dissected to extract their salivary glands. An ELISA measuring anti-S. damnosum s.l. salivary IgG and IgM was optimized and used to quantify the humoral immune response of 958 individuals. Both immunoassays differentiated negative controls from endemic participants. Salivary proteins were separated by gel-electrophoresis, and antigenic proteins visualized by immunoblot. Liquid chromatography mass spectrometry (LC-MS/MS) was performed to characterize the proteome of S. damnosum s.l. salivary glands. Several antigenic proteins were recognized, with the major ones located around 15 and 40 kDa. LC-MS/MS identified the presence of antigen 5-related protein, apyrase/nucleotidase, and hyaluronidase. CONCLUSIONS/SIGNIFICANCE This study validated for the first time human immunoassays that quantify humoral immune responses as potential markers of exposure to blackfly bites. These assays have the potential to facilitate understanding patterns of exposure as well as evaluating the impact of vector control on biting rates. Future studies need to investigate seasonal fluctuations of these antibody responses, potential cross-reactions with other bloodsucking arthropods, and thoroughly identify the most immunogenic proteins.
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13
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Cheteug G, Elanga-Ndille E, Donkeu C, Ekoko W, Oloume M, Essangui E, Nwane P, NSango SE, Etang J, Wanji S, Ayong L, Eboumbou Moukoko CE. Preliminary validation of the use of IgG antibody response to Anopheles gSG6-p1 salivary peptide to assess human exposure to malaria vector bites in two endemic areas of Cameroon in Central Africa. PLoS One 2020; 15:e0242510. [PMID: 33382730 PMCID: PMC7774847 DOI: 10.1371/journal.pone.0242510] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 11/03/2020] [Indexed: 11/25/2022] Open
Abstract
The specific immune response to the Anopheles salivary peptide could be a pertinent and complementary tool to assess the risk of malaria transmission and the effectiveness of vector control strategies. This study aimed to obtain first reliable data on the current state of the Anopheles gSG6-P1 biomarker for assess the level of exposure to Anopheles bites in high malaria endemic areas in Cameroon. Blood smears were collected from people living in the neighborhoods of Youpwe (suburban area, continental) and Manoka (rural area, Island), both areas in the coastal region of Cameroon. Malaria infection was determined using thick blood smear microscopy, whereas the level of specific IgG response to gSG-P1 peptide was assessed by enzyme-linked immunosorbent assay from the dried blood spots. Of 266 (153 from Youpwe, 113 from Manoka) malaria endemic residents (mean age: 22.8±19.8 years, age range: 6 months–94 years, male/female sex ratio: 1/1.2, with Manoka mean age: 23.71±20.53, male/female sex ratio:1/1.13 and Youpwe mean age: 22.12±19.22, male/female sex ratio 1/0.67) randomly included in the study, Plasmodium infection prevalence was significantly higher in Manoka than in Youpwe (64.6% vs 12,4%, p = 0.0001). The anti-gSG6-P1 IgG response showed a high inter-individual heterogeneity and was significantly higher among individuals from Manoka than those from Youpwe (p = 0.023). Malaria infected individuals presented a higher anti-gSG6-P1 IgG antibody response than non-infected (p = 0.0004). No significant difference in the level of specific IgG response to gSG-P1 was observed according to long lasting insecticidal nets use. Taken together, the data revealed that human IgG antibody response to Anopheles gSG-P1 salivary peptide could be also used to assess human exposure to malaria vectors in Central African region. This finding strengthens the relevance of this candidate biomarker to be used for measuring human exposure to malaria vectors worldwide.
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Affiliation(s)
- Glwadys Cheteug
- Malaria Research Unit, Centre Pasteur Cameroon, Yaounde, Cameroon
- Department of Microbiology and Parasitology, Faculty of Sciences, University of Buea, Buea, Cameroon
| | | | - Christiane Donkeu
- Malaria Research Unit, Centre Pasteur Cameroon, Yaounde, Cameroon
- Department of Animal Biology and Physiology, Faculty of Sciences, University of Yaounde, Yaounde, Cameroon
| | - Wolfgang Ekoko
- Parasitology and Entomology Research Unit, Department of Animal Biology and Organisms, Faculty of Sciences, University of Douala, Douala, Cameroon
| | - Martine Oloume
- Department of hematology, Centre Pasteur of Cameroon, Yaoundé, Cameroon
| | - Estelle Essangui
- Malaria Research Unit, Centre Pasteur Cameroon, Yaounde, Cameroon
- Parasitology and Entomology Research Unit, Department of Animal Biology and Organisms, Faculty of Sciences, University of Douala, Douala, Cameroon
| | - Philippe Nwane
- Biological Sciences Department, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon
| | - Sandrine Eveline NSango
- Malaria Research Unit, Centre Pasteur Cameroon, Yaounde, Cameroon
- Laboratory of Parasitology, Mycology and Virology, Postgraduate Training Unit for Health Sciences, Postgraduate School for Pure and Applied Sciences, University of Douala, Douala, Cameroon
| | - Josiane Etang
- Biological Sciences Department, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon
- Organisation de Coordination pour la Lutte contre les Endemies en Afrique Central, Yaounde, Cameroon
| | - Samuel Wanji
- Department of Microbiology and Parasitology, Faculty of Sciences, University of Buea, Buea, Cameroon
| | - Lawrence Ayong
- Malaria Research Unit, Centre Pasteur Cameroon, Yaounde, Cameroon
| | - Carole Else Eboumbou Moukoko
- Malaria Research Unit, Centre Pasteur Cameroon, Yaounde, Cameroon
- Biological Sciences Department, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon
- Laboratory of Parasitology, Mycology and Virology, Postgraduate Training Unit for Health Sciences, Postgraduate School for Pure and Applied Sciences, University of Douala, Douala, Cameroon
- * E-mail: ,
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14
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Buezo Montero S, Gabrieli P, Severini F, Picci L, Di Luca M, Forneris F, Facchinelli L, Ponzi M, Lombardo F, Arcà B. Analysis in a murine model points to IgG responses against the 34k2 salivary proteins from Aedes albopictus and Aedes aegypti as novel promising candidate markers of host exposure to Aedes mosquitoes. PLoS Negl Trop Dis 2019; 13:e0007806. [PMID: 31618201 PMCID: PMC6816578 DOI: 10.1371/journal.pntd.0007806] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 10/28/2019] [Accepted: 09/25/2019] [Indexed: 01/22/2023] Open
Abstract
Background Aedes mosquitoes are vectors of arboviral diseases of great relevance for public health. The recent outbreaks of dengue, Zika, chikungunya and the rapid worldwide spreading of Aedes albopictus emphasize the need for improvement of vector surveillance and control. Host antibody response to mosquito salivary antigens is emerging as a relevant additional tool to directly assess vector-host contact, monitor efficacy of control interventions and evaluate risk of arboviral transmission. Methodology/principal findings Groups of four BALB/c mice were immunized by exposure to bites of either Aedes albopictus or Aedes aegypti. The 34k2 salivary proteins from Ae. albopictus (al34k2) and Ae. aegypti (ae34k2) were expressed in recombinant form and Ae. albopictus salivary peptides were designed through B-cell epitopes prediction software. IgG responses to salivary gland extracts, peptides, al34k2 and ae34k2 were measured in exposed mice. Both al34k2 and ae34k2, with some individual and antigen-specific variation, elicited a clearly detectable antibody response in immunized mice. Remarkably, the two orthologous proteins showed very low level of immune cross-reactivity, suggesting they may eventually be developed as species-specific markers of host exposure. The al34k2 immunogenicity and the limited immune cross-reactivity to ae34k2 were confirmed in a single human donor hyperimmune to Ae. albopictus saliva. Conclusions/significance Our study shows that exposure to bites of Ae. albopictus or Ae. aegypti evokes in mice species-specific IgG responses to al34k2 or ae34k2, respectively. Deeper understanding of duration of antibody response and validation in natural conditions of human exposure to Aedes mosquitoes are certainly needed. However, our findings point to the al34k2 salivary protein as a promising potential candidate for the development of immunoassays to evaluate human exposure to Ae. albopictus. This would be a step forward in the establishment of a serological toolbox for the simultaneous assessment of human exposure to Aedes vectors and the pathogens they transmit. Taking advantage of several factors, as worldwide trading, climatic changes and urbanization, Aedes mosquitoes are impressively expanding their geographic distribution. A paradigm is provided by the rapid global spreading of Aedes albopictus, a species that is a competent vector of several arboviral diseases (e.g. dengue, Zika, chikungunya) and has been responsible of quite a few outbreaks in the last decade. Historically, vector control always played a pivotal role for the containment of arthropod-borne diseases, and this appears especially crucial for arboviral diseases for which no effective vaccines or specific medications are available. Currently, host exposure to mosquitoes is indirectly evaluated by entomological methods; however, exploitation of human immune responses to mosquito salivary proteins is emerging as a relevant additional tool, with important epidemiological implications for the evaluation of mosquito-borne disease risk. This study provides preliminary but solid indications that the 34k2 salivary proteins from Ae. albopictus and Aedes aegypti may be suitable candidates for the development of serological assays to evaluate spatial and/or temporal variation of human exposure to Aedes vectors. Combined to the presently available tools to assess arboviral exposure/infection, this may be of great help for the development of a serological toolbox allowing for the simultaneous determination of human exposure to Aedes vectors and to the pathogens they transmit.
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Affiliation(s)
- Sara Buezo Montero
- Department of Public Health and Infectious Diseases, Sapienza University, Rome, Italy
| | - Paolo Gabrieli
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Italy
| | - Francesco Severini
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Leonardo Picci
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Marco Di Luca
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Federico Forneris
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Italy
| | - Luca Facchinelli
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Marta Ponzi
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Fabrizio Lombardo
- Department of Public Health and Infectious Diseases, Sapienza University, Rome, Italy
| | - Bruno Arcà
- Department of Public Health and Infectious Diseases, Sapienza University, Rome, Italy
- * E-mail:
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15
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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] [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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16
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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] [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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17
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Mathieu-Daudé F, Claverie A, Plichart C, Boulanger D, Mphande FA, Bossin HC. Specific human antibody responses to Aedes aegypti and Aedes polynesiensis saliva: A new epidemiological tool to assess human exposure to disease vectors in the Pacific. PLoS Negl Trop Dis 2018; 12:e0006660. [PMID: 30040826 PMCID: PMC6075770 DOI: 10.1371/journal.pntd.0006660] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 08/03/2018] [Accepted: 07/03/2018] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Aedes mosquitoes severely affect the health and wellbeing of human populations by transmitting infectious diseases. In French Polynesia, Aedes aegypti is the main vector of dengue, chikungunya and Zika, and Aedes polynesiensis the primary vector of Bancroftian filariasis and a secondary vector of arboviruses. Tools for assessing the risk of disease transmission or for measuring the efficacy of vector control programmes are scarce. A promising approach to quantify the human-vector contact relies on the detection and the quantification of antibodies directed against mosquito salivary proteins. METHODOLOGY/PRINCIPAL FINDINGS An ELISA test was developed to detect and quantify the presence of immunoglobulin G (IgG) directed against proteins from salivary gland extracts (SGE) of Ae. aegypti and Ae. polynesiensis in human populations exposed to either species, through a cross-sectional study. In Tahiti and Moorea islands where Ae. aegypti and Ae. polynesiensis are present, the test revealed that 98% and 68% of individuals have developed IgG directed against Ae. aegypti and Ae. polynesiensis SGE, respectively. By comparison, ELISA tests conducted on a cohort of people from metropolitan France, not exposed to these Aedes mosquitoes, indicated that 97% of individuals had no IgG directed against SGE of either mosquito species. The analysis of additional cohorts representing different entomological Aedes contexts showed no ELISA IgG cross-reactivity between Ae. aegypti and Ae. polynesiensis SGE. CONCLUSIONS/SIGNIFICANCE The IgG response to salivary gland extracts seems to be a valid and specific biomarker of human exposure to the bites of Ae. aegypti and Ae. polynesiensis. This new immuno-epidemiological tool will enhance our understanding of people exposure to mosquito bites, facilitate the identification of areas where disease transmission risk is high and permit to evaluate the efficacy of novel vector control strategies in Pacific islands and other tropical settings.
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Affiliation(s)
- Françoise Mathieu-Daudé
- UMR MIVEGEC, IRD, CNRS, UM, Institut de Recherche pour le Développement, Nouméa, Nouvelle-Calédonie
- UMR MIVEGEC IRD, CNRS, UM, Institut de Recherche pour le Développement, Montpellier, France
| | - Aurore Claverie
- Pôle de recherche et de veille sur les maladies infectieuses émergentes, Institut Louis Malardé, Papeete, Tahiti, Polynésie française
- Laboratoire d’entomologie médicale, Institut Louis Malardé, Paea, Tahiti, Polynésie française
| | - Catherine Plichart
- Pôle de recherche et de veille sur les maladies infectieuses émergentes, Institut Louis Malardé, Papeete, Tahiti, Polynésie française
| | - Denis Boulanger
- UMR MIVEGEC IRD, CNRS, UM, Institut de Recherche pour le Développement, Montpellier, France
| | - Fingani A. Mphande
- UMR MIVEGEC, IRD, CNRS, UM, Institut de Recherche pour le Développement, Nouméa, Nouvelle-Calédonie
| | - Hervé C. Bossin
- Laboratoire d’entomologie médicale, Institut Louis Malardé, Paea, Tahiti, Polynésie française
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18
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Quinnell RJ, Soremekun S, Bates PA, Rogers ME, Garcez LM, Courtenay O. Antibody response to sand fly saliva is a marker of transmission intensity but not disease progression in dogs naturally infected with Leishmania infantum. Parasit Vectors 2018; 11:7. [PMID: 29301571 PMCID: PMC5755305 DOI: 10.1186/s13071-017-2587-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Accepted: 12/11/2017] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Antibody responses to sand fly saliva have been suggested to be a useful marker of exposure to sand fly bites and Leishmania infection and a potential tool to monitor the effectiveness of entomological interventions. Exposure to sand fly bites before infection has also been suggested to modulate the severity of the infection. Here, we test these hypotheses by quantifying the anti-saliva IgG response in a cohort study of dogs exposed to natural infection with Leishmania infantum in Brazil. METHODS IgG responses to crude salivary antigens of the sand fly Lutzomyia longipalpis were measured by ELISA in longitudinal serum samples from 47 previously unexposed sentinel dogs and 11 initially uninfected resident dogs for up to 2 years. Antibody responses were compared to the intensity of transmission, assessed by variation in the incidence of infection between seasons and between dogs. Antibody responses before patent infection were then compared with the severity of infection, assessed using tissue parasite loads and clinical symptoms. RESULTS Previously unexposed dogs acquired anti-saliva antibody responses within 2 months, and the rate of acquisition increased with the intensity of seasonal transmission. Over the following 2 years, antibody responses varied with seasonal transmission and sand fly numbers, declining rapidly in periods of low transmission. Antibody responses varied greatly between dogs and correlated with the intensity of transmission experienced by individual dogs, measured by the number of days in the field before patent infection. After infection, anti-saliva antibody responses were positively correlated with anti-parasite antibody responses. However, there was no evidence that the degree of exposure to sand fly bites before infection affected the severity of the infection. CONCLUSIONS Anti-saliva antibody responses are a marker of current transmission intensity in dogs exposed to natural infection with Leishmania infantum, but are not associated with the outcome of infection.
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Affiliation(s)
- Rupert J. Quinnell
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Seyi Soremekun
- Zeeman Institute and School of Life Sciences, University of Warwick, Coventry, UK
- Faculty of Infectious Tropical Diseases, Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK
| | - Paul A. Bates
- Division of Biomedical and Life Sciences, Lancaster University, Lancaster, UK
| | - Matthew E. Rogers
- Faculty of Infectious Tropical Diseases, Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK
| | - Lourdes M. Garcez
- Instituto Evandro Chagas, Belém, Pará Brazil
- Centro do Ciências Biológicas e da Saúde, Universidade do Estado do Pará, Belém, Pará Brazil
| | - Orin Courtenay
- Zeeman Institute and School of Life Sciences, University of Warwick, Coventry, UK
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19
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Idris ZM, Chan CW, Mohammed M, Kalkoa M, Taleo G, Junker K, Arcà B, Drakeley C, Kaneko A. Serological measures to assess the efficacy of malaria control programme on Ambae Island, Vanuatu. Parasit Vectors 2017; 10:204. [PMID: 28441959 PMCID: PMC5405492 DOI: 10.1186/s13071-017-2139-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 04/13/2017] [Indexed: 01/10/2023] Open
Abstract
Background Seroepidemiology can provide evidence for temporal changes in malaria transmission and is an important tool to evaluate the effectiveness of control interventions. During the early 2000s, Vanuatu experienced an acute increase in malaria incidence due to a lapse in funding for vector control. After the distribution of subsidised insecticide-treated nets (ITNs) resumed in 2003, malaria incidence decreased in the subsequent years. This study was conducted to find the serological evidence supporting the impact of ITN on exposure to Anopheles vector bites and parasite prevalence. Methods On Ambae Island, blood samples were collected from 231 and 282 individuals in 2003 and 2007, respectively. Parasite prevalence was determined by microscopy. Antibodies to three Plasmodium falciparum (PfSE, PfMSP-119, and PfAMA-1) and three Plasmodium vivax (PvSE, PvMSP-119, and PvAMA-1) antigens, as well as the Anopheles-specific salivary antigen gSG6, were detected by ELISA. Age-specific seroprevalence was analysed using a reverse catalytic modelling approach to estimate seroconversion rates (SCRs). Results Parasite rate decreased significantly (P < 0.001) from 19.0% in 2003 to 3.2% in 2007, with a shift from P. falciparum predominance to P. falciparum-P. vivax co-dominance. Significant (P < 0.001) decreases were observed in seroprevalence to all three P. falciparum antigens but only two of three P. vivax antigens (except PvAMA-1; P = 0.153), consistent with the more pronounced decrease in P. falciparum prevalence. Seroprevalence to gSG6 also decreased significantly (P < 0.001), suggesting that reduced exposure to vector bites was important to the decrease in parasite prevalence between 2003 and 2007. Analyses of age-specific seroprevalence showed a three-fold decrease in P. falciparum transmission, but the evidence for the decrease in P. vivax transmission was less clear. Conclusions Serological markers pointed to the effectiveness of ITNs in reducing malaria prevalence on Ambae Island between 2003 and 2007. The recombinant gSG6 antigen originally developed to indicate exposure to the Afrotropical vector An. gambiae may be used in the Pacific to complement the traditional measure of entomological inoculation rate (EIR).
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Affiliation(s)
- Zulkarnain Md Idris
- Island Malaria Group, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden. .,Department of Parasitology and Medical Entomology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia.
| | - Chim W Chan
- Island Malaria Group, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Mubasher Mohammed
- Island Malaria Group, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | | | | | - Klara Junker
- Department of Immunology and Infection, London School of Hygiene & Tropical Medicine, London, UK.,Yeast and Fermentation, Carlsberg Research Laboratory, Copenhagen, Denmark
| | - Bruno Arcà
- Department of Public Health and Infectious Diseases, Parasitology Section, Sapienza University of Rome, Rome, Italy
| | - Chris Drakeley
- Department of Immunology and Infection, London School of Hygiene & Tropical Medicine, London, UK
| | - Akira Kaneko
- Island Malaria Group, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.,Department of Parasitology and Research Centre for Infectious Disease Sciences, Graduate School of Medicine, Osaka City University, Osaka, Japan.,Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
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20
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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] [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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21
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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: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [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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22
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Hemme RR, Poole-Smith BK, Hunsperger EA, Felix GE, Horiuchi K, Biggerstaff BJ, Lopez-Ortiz R, Barrera R. Non-human primate antibody response to mosquito salivary proteins: Implications for dengue virus transmission in Puerto Rico. Acta Trop 2016; 164:369-374. [PMID: 27593498 DOI: 10.1016/j.actatropica.2016.08.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 06/24/2016] [Accepted: 08/31/2016] [Indexed: 01/31/2023]
Abstract
An important step to incriminate a mosquito as a vector of a disease pathogen is finding evidence of direct contact between the mosquito and humans. Typically, this is accomplished through landing/biting catches, or host blood meal analysis in engorged mosquitoes via immunologic assays. An alternate approach is to identify the presence of specific mosquito anti-saliva protein antibodies in the blood of exposed hosts. Following the discovery of dengue infected, free roaming non-human primates in Puerto Rico, we investigated which mosquito species had bitten these primates using a serologic assay. Serum samples from 20 patas monkeys (Erythrocebus patas) and two rhesus macaques (Macaca mulatta) were used to evaluate mosquito bite exposure to Aedes aegypti, Aedes mediovittatus, Aedes taeniorhynchus, and Culex quinquefasciatus mosquitoes. Of 22 non-human primates examined 20 (90%), 17 (77%), 13 (59%), and 7 (31%) were positive for exposure to Ae. mediovittatus, Cx. quinquefasciatus, Ae. taeniorhynchus, and Ae. aegypti, respectively. Our findings indicated that free-roaming primates in Puerto Rico were exposed to the bites of one proven dengue vector, Ae. aegypti and one potential dengue vector, Ae. mediovittatus.
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Affiliation(s)
- Ryan R Hemme
- Dengue Branch, Centers for Disease Control and Prevention, San Juan 00920, Puerto Rico.
| | | | | | - Gilberto E Felix
- Dengue Branch, Centers for Disease Control and Prevention, San Juan 00920, Puerto Rico.
| | - Kalanthe Horiuchi
- Office of the Director (Division of Vector Borne Diseases), Centers for Disease Control and Prevention, Fort Collins, CO 80521, United States.
| | - Brad J Biggerstaff
- Office of the Director (Division of Vector Borne Diseases), Centers for Disease Control and Prevention, Fort Collins, CO 80521, United States.
| | - Ricardo Lopez-Ortiz
- Fish and Wildlife Bureau, Puerto Rico Department of Natural & Environmental Resources, San Juan 00936, Puerto Rico.
| | - Roberto Barrera
- Dengue Branch, Centers for Disease Control and Prevention, San Juan 00920, Puerto Rico.
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23
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Armiyanti Y, Arifianto RP, Riana EN, Senjarini K, Widodo W, Fitri LE, Sardjono TW. Identification of antigenic proteins from salivary glands of female Anopheles maculatus by proteomic analysis. Asian Pac J Trop Biomed 2016. [DOI: 10.1016/j.apjtb.2016.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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24
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Londono-Renteria B, Cardenas JC, Troupin A, Colpitts TM. Natural Mosquito-Pathogen Hybrid IgG4 Antibodies in Vector-Borne Diseases: A Hypothesis. Front Immunol 2016; 7:380. [PMID: 27746778 PMCID: PMC5040711 DOI: 10.3389/fimmu.2016.00380] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 09/08/2016] [Indexed: 12/24/2022] Open
Abstract
Chronic exposure to antigens may favor the production of IgG4 antibodies over other antibody types. Recent studies have shown that up to a 30% of normal human IgG4 is bi-specific and is able to recognize two antigens of different nature. A requirement for this specificity is the presence of both eliciting antigens in the same time and at the same place where the immune response is induced. During transmission of most vector-borne diseases, the pathogen is delivered to the vertebrate host along with the arthropod saliva during blood feeding and previous studies have shown the existence of IgG4 antibodies against mosquito salivary allergens. However, there is very little ongoing research or information available regarding IgG4 bi-specificity with regard to infectious disease, particularly during immune responses to vector-borne diseases, such as malaria, filariasis, or dengue virus infection. Here, we provide background information and present our hypothesis that IgG4 may not only be a useful tool to measure exposure to infected mosquito bites, but that these bi-specific antibodies may also play an important role in modulation of the immune response against malaria and other vector-borne diseases in endemic settings.
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Affiliation(s)
- Berlin Londono-Renteria
- Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine , Columbia, SC , USA
| | - Jenny C Cardenas
- Clinical Laboratory, Hospital Los Patios , Los Patios , Colombia
| | - Andrea Troupin
- Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine , Columbia, SC , USA
| | - Tonya M Colpitts
- Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine , Columbia, SC , USA
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Doucoure S, Drame PM. Salivary Biomarkers in the Control of Mosquito-Borne Diseases. INSECTS 2015; 6:961-76. [PMID: 26593952 PMCID: PMC4693181 DOI: 10.3390/insects6040961] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 06/15/2015] [Accepted: 09/14/2015] [Indexed: 11/26/2022]
Abstract
Vector control remains the most effective measure to prevent the transmission of mosquito-borne diseases. However, the classical entomo-parasitological methods used to evaluate the human exposure to mosquito bites and the effectiveness of control strategies are indirect, labor intensive, and lack sensitivity in low exposure/transmission areas. Therefore, they are limited in their accuracy and widespread use. Studying the human antibody response against the mosquito salivary proteins has provided new biomarkers for a direct and accurate evaluation of the human exposure to mosquito bites, at community and individual levels. In this review, we discuss the development, applications and limits of these biomarkers applied to Aedes- and Anopheles-borne diseases.
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Affiliation(s)
- Souleymane Doucoure
- Institut de Recherche pour le Développement, Unité de Recherche sur les Maladies Infectieuses Tropicales Emergentes (URMITE) UM63: CNRS7278-IRD 198-INSERM U1095 Campus IRD-UCAD, BP 1386, Dakar 18524, Sénégal.
| | - Papa Makhtar Drame
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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Martín-Martín I, Molina R, Jiménez M. Kinetics of Anti-Phlebotomus perniciosus Saliva Antibodies in Experimentally Bitten Mice and Rabbits. PLoS One 2015; 10:e0140722. [PMID: 26569103 PMCID: PMC4646634 DOI: 10.1371/journal.pone.0140722] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 09/28/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Sand flies are hematophagous arthropods that act as vectors of Leishmania parasites. When hosts are bitten they develop cellular and humoral responses against sand fly saliva. A positive correlation has been observed between the number of bites and antibody levels indicating that anti-saliva antibody response can be used as marker of exposure to sand flies. Little is known about kinetics of antibodies against Phlebotomus perniciosus salivary gland homogenate (SGH) or recombinant salivary proteins (rSP). This work focused on the study of anti-P. perniciosus saliva antibodies in sera of mice and rabbits that were experimentally exposed to the bites of uninfected sand flies. METHODOLOGY/PRINCIPAL FINDINGS Anti-saliva antibodies were evaluated by ELISA and Western blot. In addition, antibody levels against two P. perniciosus rSP, apyrase rSP01B and D7 related protein rSP04 were determined in mice sera. Anti-saliva antibody levels increased along the immunizations and correlated with the number of sand fly bites. Anti-SGH antibody levels were detected in sera of mice five weeks after exposure, and persisted for at least three months. Anti-apyrase rSP01B antibodies followed similar kinetic responses than anti-SGH antibodies while rSP04 showed a delayed response and exhibited a greater variability among sera of immunized mice. In rabbits, anti-saliva antibodies appeared after the second week of exposure and IgG antibodies persisted at high levels, even 7 months post-exposure. CONCLUSIONS/SIGNIFICANCE Our results contributed to increase the knowledge on the type of immune response P. perniciosus saliva and individual proteins elicited highlighting the use of rSP01B as an epidemiological marker of exposure. Anti-saliva kinetics in sera of experimentally bitten rabbits were studied for the first time. Results with rabbit model provided useful information for a better understanding of the anti-saliva antibody levels found in wild leporids in the human leishmaniasis focus in the Madrid region, Spain.
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Affiliation(s)
- Inés Martín-Martín
- Unidad de Entomología Médica, Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
- * E-mail:
| | - Ricardo Molina
- Unidad de Entomología Médica, Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Maribel Jiménez
- Unidad de Entomología Médica, Servicio de Parasitología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
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27
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Drame PM, Poinsignon A, Dechavanne C, Cottrell G, Farce M, Ladekpo R, Massougbodji A, Cornélie S, Courtin D, Migot-Nabias F, Garcia A, Remoué F. Specific antibodies to Anopheles gSG6-P1 salivary peptide to assess early childhood exposure to malaria vector bites. Malar J 2015. [PMID: 26198354 PMCID: PMC4511589 DOI: 10.1186/s12936-015-0800-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Background The estimates of risk of malaria in early childhood are imprecise given the current entomologic and parasitological tools. Thus, the utility of anti-Anopheles salivary gSG6-P1 peptide antibody responses in measuring exposure to Anopheles bites during early infancy has been assessed. Methods Anti-gSG6-P1 IgG and IgM levels were evaluated in 133 infants (in Benin) at three (M3), six (M6), nine (M9) and 12 (M12) months of age. Specific IgG levels were also assessed in their respective umbilical cord blood (IUCB) and maternal blood (MPB). Results At M3, 93.98 and 41.35% of infants had anti-gSG6-P1 IgG and IgM Ab, respectively. Specific median IgG and IgM levels gradually increased between M3 and M6 (p < 0.0001 and p < 0.001), M6–M9 (p < 0.0001 and p = 0.085) and M9–M12 (p = 0.002 and p = 0.03). These levels were positively associated with the Plasmodium falciparum infection intensity (p = 0.006 and 0.003), and inversely with the use of insecticide-treated bed nets (p = 0.003 and 0.3). Levels of specific IgG in the MPB were positively correlated to those in the IUCB (R = 0.73; p < 0.0001) and those at M3 (R = 0.34; p < 0.0001). Conclusion The exposure level to Anopheles bites, and then the risk of malaria infection, can be evaluated in young infants by assessing anti-gSG6-P1 IgM and IgG responses before and after 6-months of age, respectively. This tool can be useful in epidemiological evaluation and surveillance of malaria risk during the first year of life.
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Affiliation(s)
- Papa M Drame
- UMR MIVEGEC (IRD224-CNRS5290-Universités Montpellier 1 et 2), Institut de Recherche pour le Développement (IRD), BP64501, 34394, Montpellier, France. .,IRD-UMR MIVEGEC (IRD224-CNRS5290-Universités Montpellier 1 et 2), Centre de Recherche Entomologique de Cotonou (CREC), 01 BP 4414RP, Cotonou, Benin. .,Laboratory of Parasitic Diseases, NIAID, NIH, 4 Center Dr, Bethesda, MD, 20892-0425, USA.
| | - Anne Poinsignon
- UMR MIVEGEC (IRD224-CNRS5290-Universités Montpellier 1 et 2), Institut de Recherche pour le Développement (IRD), BP64501, 34394, Montpellier, France.
| | - Célia Dechavanne
- IRD UMR 216 Mère et enfant face aux infections tropicales, 75006, Paris, France. .,Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France.
| | - Gilles Cottrell
- IRD UMR 216 Mère et enfant face aux infections tropicales, 75006, Paris, France. .,Laboratoire de Mathématiques Appliquées, Université Paris Descartes, 75006, Paris, France.
| | - Manon Farce
- UMR MIVEGEC (IRD224-CNRS5290-Universités Montpellier 1 et 2), Institut de Recherche pour le Développement (IRD), BP64501, 34394, Montpellier, France.
| | - Rodolphe Ladekpo
- Centre d'Etudes et de Recherche sur le Paludisme Associé à la Grossesse et à l'Enfant (CERPAGE), Cotonou, Benin.
| | - Achille Massougbodji
- Centre d'Etudes et de Recherche sur le Paludisme Associé à la Grossesse et à l'Enfant (CERPAGE), Cotonou, Benin. .,Faculté des Sciences de la Santé, Université d'Abomey-Calavi, 01 BP 188, Cotonou, Benin.
| | - Sylvie Cornélie
- UMR MIVEGEC (IRD224-CNRS5290-Universités Montpellier 1 et 2), Institut de Recherche pour le Développement (IRD), BP64501, 34394, Montpellier, France.
| | - David Courtin
- IRD UMR 216 Mère et enfant face aux infections tropicales, 75006, Paris, France. .,Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France. .,Centre d'Etudes et de Recherche sur le Paludisme Associé à la Grossesse et à l'Enfant (CERPAGE), Cotonou, Benin.
| | - Florence Migot-Nabias
- IRD UMR 216 Mère et enfant face aux infections tropicales, 75006, Paris, France. .,Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France.
| | - André Garcia
- IRD UMR 216 Mère et enfant face aux infections tropicales, 75006, Paris, France. .,Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France.
| | - Franck Remoué
- UMR MIVEGEC (IRD224-CNRS5290-Universités Montpellier 1 et 2), Institut de Recherche pour le Développement (IRD), BP64501, 34394, Montpellier, France. .,IRD-UMR MIVEGEC (IRD224-CNRS5290-Universités Montpellier 1 et 2), Centre de Recherche Entomologique de Cotonou (CREC), 01 BP 4414RP, Cotonou, Benin.
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Londono-Renteria B, Patel JC, Vaughn M, Funkhauser S, Ponnusamy L, Grippin C, Jameson SB, Apperson C, Mores CN, Wesson DM, Colpitts TM, Meshnick SR. Long-Lasting Permethrin-Impregnated Clothing Protects Against Mosquito Bites in Outdoor Workers. Am J Trop Med Hyg 2015. [PMID: 26195460 DOI: 10.4269/ajtmh.15-0130] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Outdoor exposure to mosquitoes is a risk factor for many diseases, including malaria and dengue. We have previously shown that long-lasting permethrin-impregnated clothing protects against tick and chigger bites in a double-blind randomized controlled trial in North Carolina outdoor workers. Here, we evaluated whether this clothing is protective against mosquito bites by measuring changes in antibody titers to mosquito salivary gland extracts. On average, there was a 10-fold increase in titer during the spring and summer when mosquito exposure was likely to be the highest. During the first year of the study, the increase in titer in subjects wearing treated uniforms was 2- to 2.5-fold lower than that of control subjects. This finding suggests that long-lasting permethrin-impregnated clothing provided protection against mosquito bites.
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Affiliation(s)
- Berlin Londono-Renteria
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Jaymin C Patel
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Meagan Vaughn
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Sheana Funkhauser
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Loganathan Ponnusamy
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Crystal Grippin
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Sam B Jameson
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Charles Apperson
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Christopher N Mores
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Dawn M Wesson
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Tonya M Colpitts
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Steven R Meshnick
- Department of Pathology, Immunology and Microbiology, University of South Carolina, Columbia, South Carolina; Department of Tropical Medicine, Tulane University, New Orleans, Louisiana; Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Entomology, North Carolina State University, Raleigh, North Carolina; Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, Louisiana
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Carnevale P, Toto JC, Besnard P, Santos MAD, Fortes F, Allan R, Manguin S. Spatio-temporal variations of Anopheles coluzzii and An. gambiae and their Plasmodium infectivity rates in Lobito, Angola. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2015; 40:172-179. [PMID: 26047198 DOI: 10.1111/jvec.12147] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Accepted: 01/19/2015] [Indexed: 06/04/2023]
Abstract
From 2003 to 2007, entomological surveys were conducted in Lobito town (Benguela Province, Angola) to determine which Anopheles species were present and to identify the vectors responsible for malaria transmission in areas where workers of the Sonamet Company live. Two types of surveys were conducted: (1) time and space surveys in the low and upper parts of Lobito during the rainy and dry periods; (2) a two-year longitudinal study in Sonamet workers' houses provided with long-lasting insecticide-treated nets (LLIN), "PermaNet," along with the neighboring community. Both species, An. coluzzii (M molecular form) and An. gambiae (S molecular form), were collected. Anopheles coluzzii was predominant during the dry season in the low part of Lobito where larvae develop in natural ponds and temporary pools. However, during the rainy season, An. gambiae was found in higher proportions in the upper part of the town where larvae were collected in domestic water tanks built near houses. Anopheles melas and An. listeri were captured in higher numbers during the dry season and in the low part of Lobito where larvae develop in stagnant brackish water pools. The infectivity rates of An. gambiae s.l. varied from 0.90% to 3.41%.
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Affiliation(s)
- Pierre Carnevale
- Institut de Recherche pour le Développement (IRD), Montpellier, France, 34394
| | - Jean-Claude Toto
- Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, BP, Cameroun, 288
| | | | | | | | | | - Sylvie Manguin
- Institut de Recherche pour le Développement (IRD), UMR-MD3, Montpellier, France, 34093.
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Badu K, Gyan B, Appawu M, Mensah D, Dodoo D, Yan G, Drakeley C, Zhou G, Owusu-Dabo E, Koram KA. Serological evidence of vector and parasite exposure in Southern Ghana: the dynamics of malaria transmission intensity. Parasit Vectors 2015; 8:251. [PMID: 25928847 PMCID: PMC4418069 DOI: 10.1186/s13071-015-0861-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 04/15/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Seroepidemiology provides robust estimates for tracking malaria transmission when intensity is low and useful when there is no baseline entomological data. Serological evidence of exposure to malaria vectors and parasite contribute to our understanding of the risk of pathogen transmission, and facilitates implementation of targeted interventions. Ab to Anopheles gambiae salivary peptide (gSG6-P1) and merozoite surface protein one (MSP-1(19)) reflect human exposure to malaria vectors and parasites. This study estimated malaria transmission dynamics using serological evidence of vector and parasite exposure in southern Ghana. METHODS Total IgG responses to both antigens in an age stratified cohort (<5, 5-14, >14) were measured from South-eastern Ghana. 295 randomly selected sera were analyzed from archived samples belonging to a cohort study that were followed at 3 consecutive survey months (n = 885); February, May and August 2009. Temporal variations in seroprevalence of both antigens as well as differences between the age-stratified cohorts were determined by χ (2) test with p < 0.05 statistically significant. Non-parametric repeated ANOVA - Friedman's test was used to test differences in antibody levels. Seroprevalence data were fitted to reversible catalytic model to estimate sero-conversion rates. RESULTS Whereas parasite prevalence was generally low 2.4%, 2.7% and 2.4% with no apparent trends with season, seroprevalence to both gSG6-P1 and MSP1(19) were high (59%, 50.9%, 52.2%) and 57.6%, 52.3% and 43.6% in respective order from Feb. to August. Repeated measures ANOVA showed differences in median antibody levels across surveys with specific significant differences between February and May but not August by post hoc Dunn's multiple comparison tests for gSG6-P1. For MSP1(19), no differences were observed in antibody levels between February and May but a significant decline was observed from May to August. Seroconversion rates for gSG6-P1 increased by 1.5 folds from February to August and 3 folds for MSP1(19). CONCLUSION Data suggests exposure to infectious bites may be declining whereas mosquito bites remains high. Sustained malaria control efforts and surveillance are needed to drive malaria further down and to prevent catastrophic rebound. Operational factors for scaling up have been discussed.
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Affiliation(s)
- Kingsley Badu
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Science University of Ghana, LG581, , Legon, Accra, Ghana.
| | - Ben Gyan
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Science University of Ghana, LG581, , Legon, Accra, Ghana.
| | - Maxwell Appawu
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, College of Health Science University of Ghana, LG581, , Legon, Accra, Ghana.
| | - Daniel Mensah
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Science University of Ghana, LG581, , Legon, Accra, Ghana.
| | - Daniel Dodoo
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Science University of Ghana, LG581, , Legon, Accra, Ghana.
| | - Guiyun Yan
- Program in Public Health, Room 3038, Hewitt Hall, College of Health Science, University of California, Irvine, CA, 92697-4050, USA.
| | - Chris Drakeley
- London School of Hygiene and Tropical Medicine, London, UK.
| | - Guofa Zhou
- Program in Public Health, Room 3038, Hewitt Hall, College of Health Science, University of California, Irvine, CA, 92697-4050, USA.
| | - Ellis Owusu-Dabo
- Kumasi Centre for Collaborative Research in Tropical Medicine, School of Medical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.
| | - Kwadwo Ansah Koram
- Department of Epidemiology, Noguchi Memorial Institute for Medical Research, College of Health Science University of Ghana, LG581, , Legon, Accra, Ghana.
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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] [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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Hai VV, Almeras L, Socolovschi C, Raoult D, Parola P, Pagès F. Monitoring human tick-borne disease risk and tick bite exposure in Europe: available tools and promising future methods. Ticks Tick Borne Dis 2014; 5:607-19. [PMID: 25178542 DOI: 10.1016/j.ttbdis.2014.07.022] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 07/28/2014] [Accepted: 07/28/2014] [Indexed: 12/30/2022]
Abstract
Ticks are the main vector for infectious disease pathogens in both humans and animals, and tick-borne diseases are currently spreading throughout Europe. Various surveillance methods have been developed to estimate the burden and risk of tick-borne diseases and host exposure to tick bites. The ultimate aims of these approaches are to determine the risk level of a tick-borne disease in a given area, determine its health priority, identify the at-risk population and propose specific countermeasures or complementary studies as needed. The purpose of this review is to present the current methods for monitoring the circulation of tick-borne diseases and to highlight the use of salivary antigens as original and recently developed serological tools that could be useful for tick bite risk assessment and could improve the current surveillance methods.
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Affiliation(s)
- Vinh Vu Hai
- Aix-Marseille Université, Unité de Recherche en Maladies Infectieuses et Tropicales Emergentes (URMITE), UM 63, CNRS 7278, IRD 198, Inserm 1095, WHO Collaborative Center for Rickettsioses and Other Arthropod-Borne Bacterial Diseases, Faculté de Médecine, 27 Boulevard Jean Moulin, 13385 Marseille Cedex 5, France; Institut de Recherche Biomédicale des Armées (IRBA), Antenne Marseille, Unité de Parasitologie, URMITE UMR 6236, GSBdD de Marseille Aubagne, 111 Avenue de la Corse BP 40026, 13568 Marseille Cedex 02, France
| | - Lionel Almeras
- Aix-Marseille Université, Unité de Recherche en Maladies Infectieuses et Tropicales Emergentes (URMITE), UM 63, CNRS 7278, IRD 198, Inserm 1095, WHO Collaborative Center for Rickettsioses and Other Arthropod-Borne Bacterial Diseases, Faculté de Médecine, 27 Boulevard Jean Moulin, 13385 Marseille Cedex 5, France; Institut de Recherche Biomédicale des Armées (IRBA), Antenne Marseille, Unité de Parasitologie, URMITE UMR 6236, GSBdD de Marseille Aubagne, 111 Avenue de la Corse BP 40026, 13568 Marseille Cedex 02, France
| | - Cristina Socolovschi
- Aix-Marseille Université, Unité de Recherche en Maladies Infectieuses et Tropicales Emergentes (URMITE), UM 63, CNRS 7278, IRD 198, Inserm 1095, WHO Collaborative Center for Rickettsioses and Other Arthropod-Borne Bacterial Diseases, Faculté de Médecine, 27 Boulevard Jean Moulin, 13385 Marseille Cedex 5, France
| | - Didier Raoult
- Aix-Marseille Université, Unité de Recherche en Maladies Infectieuses et Tropicales Emergentes (URMITE), UM 63, CNRS 7278, IRD 198, Inserm 1095, WHO Collaborative Center for Rickettsioses and Other Arthropod-Borne Bacterial Diseases, Faculté de Médecine, 27 Boulevard Jean Moulin, 13385 Marseille Cedex 5, France
| | - Philippe Parola
- Aix-Marseille Université, Unité de Recherche en Maladies Infectieuses et Tropicales Emergentes (URMITE), UM 63, CNRS 7278, IRD 198, Inserm 1095, WHO Collaborative Center for Rickettsioses and Other Arthropod-Borne Bacterial Diseases, Faculté de Médecine, 27 Boulevard Jean Moulin, 13385 Marseille Cedex 5, France.
| | - Frédéric Pagès
- Aix-Marseille Université, Unité de Recherche en Maladies Infectieuses et Tropicales Emergentes (URMITE), UM 63, CNRS 7278, IRD 198, Inserm 1095, WHO Collaborative Center for Rickettsioses and Other Arthropod-Borne Bacterial Diseases, Faculté de Médecine, 27 Boulevard Jean Moulin, 13385 Marseille Cedex 5, France; CIRE/ARS Océan Indien, 2 bis Avenue Georges Brassens CS 60050, 97408 Saint Denis Cedex 9, Reunion.
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Serological responses and biomarker evaluation in mice and pigs exposed to tsetse fly bites. PLoS Negl Trop Dis 2014; 8:e2911. [PMID: 24853371 PMCID: PMC4031185 DOI: 10.1371/journal.pntd.0002911] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 04/16/2014] [Indexed: 12/02/2022] Open
Abstract
Background Tsetse flies are obligate blood-feeding insects that transmit African trypanosomes responsible for human sleeping sickness and nagana in livestock. The tsetse salivary proteome contains a highly immunogenic family of the endonuclease-like Tsal proteins. In this study, a recombinant version of Tsal1 (rTsal1) was evaluated in an indirect ELISA to quantify the contact with total Glossina morsitans morsitans saliva, and thus the tsetse fly bite exposure. Methodology/Principal Findings Mice and pigs were experimentally exposed to different G. m. morsitans exposure regimens, followed by a long-term follow-up of the specific antibody responses against total tsetse fly saliva and rTsal1. In mice, a single tsetse fly bite was sufficient to induce detectable IgG antibody responses with an estimated half-life of 36–40 days. Specific antibody responses could be detected for more than a year after initial exposure, and a single bite was sufficient to boost anti-saliva immunity. Also, plasmas collected from tsetse-exposed pigs displayed increased anti-rTsal1 and anti-saliva IgG levels that correlated with the exposure intensity. A strong correlation between the detection of anti-rTsal1 and anti-saliva responses was recorded. The ELISA test performance and intra-laboratory repeatability was adequate in the two tested animal models. Cross-reactivity of the mouse IgGs induced by exposure to different Glossina species (G. m. morsitans, G. pallidipes, G. palpalis gambiensis and G. fuscipes) and other hematophagous insects (Stomoxys calcitrans and Tabanus yao) was evaluated. Conclusion This study illustrates the potential use of rTsal1 from G. m. morsitans as a sensitive biomarker of exposure to a broad range of Glossina species. We propose that the detection of anti-rTsal1 IgGs could be a promising serological indicator of tsetse fly presence that will be a valuable tool to monitor the impact of tsetse control efforts on the African continent. Salivary proteins of hematophagous disease vectors represent potential biomarkers of exposure and could be used in serological assays that are complementary to entomological surveys. We illustrate that a recombinant version of the highly immunogenic Tsal1 protein of the savannah tsetse fly (Glossina morsitans morsitans) is a sensitive immunological probe to detect contact with tsetse flies. Experimental exposure of mice and pigs to different regimens of tsetse fly bites combined with serological testing revealed that rTsal1 is a sensitive indicator that can differentiate the various degrees of exposure of animals. Tsetse-induced antibodies persisted relatively long, and an efficient boosting of immunity was observed upon re-exposure. Recombinant Tsal1 is a promising candidate to detect contact with various tsetse species, which would enable screening of populations or herds for exposure to tsetse flies in various areas on the African continent. This exposure indicator could be a valuable tool to monitor the impact of vector control programs and to detect re-invasion of cleared areas by tsetse flies.
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Human antibody response to Aedes albopictus salivary proteins: a potential biomarker to evaluate the efficacy of vector control in an area of Chikungunya and Dengue Virus transmission. BIOMED RESEARCH INTERNATIONAL 2014; 2014:746509. [PMID: 24822216 PMCID: PMC4005104 DOI: 10.1155/2014/746509] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 03/06/2014] [Accepted: 03/19/2014] [Indexed: 11/17/2022]
Abstract
Aedes borne viruses represent public health problems in southern countries and threat to emerge in the developed world. Their control is currently based on vector population control. Much effort is being devoted to develop new tools to control such arbovirus. Recent findings suggest that the evaluation of human antibody (Ab) response to arthropod salivary proteins is relevant to measuring the level of human exposure to mosquito bites. Using an immunoepidemiological approach, the present study aimed to assess the usefulness of the salivary biomarker for measuring the efficacy of Ae. albopictus control strategies in La Reunion urban area. The antisaliva Ab response of adult humans exposed to Ae. albopictus was evaluated before and after vector control measures. Our results showed a significant correlation between antisaliva Ab response and the level of exposure to vectors bites. The decrease of Ae. albopictus density has been detected by this biomarker two weeks after the implementation of control measures, suggesting its potential usefulness for evaluating control strategies in a short time period. The identification of species specific salivary proteins/peptides should improve the use of this biomarker.
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Dorňáková V, Salazar-Sanchez R, Borrini-Mayori K, Carrion-Navarro O, Levy MZ, Schaub GA, Schwarz A. Characterization of guinea pig antibody responses to salivary proteins of Triatoma infestans for the development of a triatomine exposure marker. PLoS Negl Trop Dis 2014; 8:e2783. [PMID: 24699441 PMCID: PMC3974673 DOI: 10.1371/journal.pntd.0002783] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Accepted: 02/24/2014] [Indexed: 11/22/2022] Open
Abstract
Background Salivary proteins of Triatoma infestans elicit humoral immune responses in their vertebrate hosts. These immune responses indicate exposure to triatomines and thus can be a useful epidemiological tool to estimate triatomine infestation. In the present study, we analyzed antibody responses of guinea pigs to salivary antigens of different developmental stages of four T. infestans strains originating from domestic and/or peridomestic habitats in Argentina, Bolivia, Chile and Peru. We aimed to identify developmental stage- and strain-specific salivary antigens as potential markers of T. infestans exposure. Methodology and Principal Findings In SDS-PAGE analysis of salivary proteins of T. infestans the banding pattern differed between developmental stages and strains of triatomines. Phenograms constructed from the salivary profiles separated nymphal instars, especially the 5th instar, from adults. To analyze the influence of stage- and strain-specific differences in T. infestans saliva on the antibody response of guinea pigs, twenty-one guinea pigs were exposed to 5th instar nymphs and/or adults of different T. infestans strains. Western blot analyses using sera of exposed guinea pigs revealed stage- and strain-specific variations in the humoral response of animals. In total, 27 and 17 different salivary proteins reacted with guinea pig sera using IgG and IgM antibodies, respectively. Despite all variations of recognized salivary antigens, an antigen of 35 kDa reacted with sera of almost all challenged guinea pigs. Conclusion Salivary antigens are increasingly considered as an epidemiological tool to measure exposure to hematophagous arthropods, but developmental stage- and strain-specific variations in the saliva composition and the respective differences of immunogenicity are often neglected. Thus, the development of a triatomine exposure marker for surveillance studies after triatomine control campaigns requires detailed investigations. Our study resulted in the identification of a potential antigen as useful marker of T. infestans exposure. Chagas disease is caused by the protozoan parasite Trypanosoma cruzi, and currently affects approximately 8 million people in Latin American countries. Although vector control campaigns against the most effective Chagas disease vector, Triatoma infestans, have been highly successful, T. infestans is re-establishing in once-endemic regions. To monitor re-establishing triatomines, new epidemiological tools are needed. Antibody responses of hosts to triatomine salivary proteins represent a promising tool to detect biting bugs, and highly immunogenic salivary antigens may be used as markers of triatomine exposure. Therefore, we analyzed the antibody response of guinea pigs, common peridomestic hosts of T. infestans, to salivary proteins of nymphs and adults of four different T. infestans strains from Argentina, Bolivia, Chile and Peru. Developmental stage- and strain-specific proteins in the saliva of T. infestans influenced the antibody response of guinea pigs, and different salivary antigens were recognized by guinea pig sera. Despite the variations of immunogenic salivary antigens, a 35 kDa antigen was recognized by almost all guinea pig sera and this antigen may be a useful marker of T. infestans exposure.
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Affiliation(s)
- Veronika Dorňáková
- Institute of Parasitology, Biology Centre of the Academy of Sciences of Czech Republic, Ceske Budejovice, Czech Republic
- Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic
| | | | | | | | - Michael Z. Levy
- Universidad Peruana Cayetano Heredia, Sede de Arequipa, Arequipa, Peru
- Department of Biostatistics and Epidemiology, Center for Clinical Epidemiology and Biostatistics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Günter A. Schaub
- Zoology/Parasitology Group, Ruhr-University Bochum, Bochum, Germany
| | - Alexandra Schwarz
- Institute of Parasitology, Biology Centre of the Academy of Sciences of Czech Republic, Ceske Budejovice, Czech Republic
- * E-mail:
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Londono-Renteria B, Cardenas JC, Cardenas LD, Christofferson RC, Chisenhall DM, Wesson DM, McCracken MK, Carvajal D, Mores CN. Use of anti-Aedes aegypti salivary extract antibody concentration to correlate risk of vector exposure and dengue transmission risk in Colombia. PLoS One 2013; 8:e81211. [PMID: 24312537 PMCID: PMC3846924 DOI: 10.1371/journal.pone.0081211] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 10/09/2013] [Indexed: 02/03/2023] Open
Abstract
Norte de Santander is a region in Colombia with a high incidence of dengue virus (DENV). In this study, we examined the serum concentration of anti-Aedes salivary gland extract (SGE) antibodies as a biomarker of DENV infection and transmission, and assessed the duration of anti-SGE antibody concentration after exposure to the vector ceased. We also determined whether SGE antibody concentration could differentiate between positive and negative DENV infected individuals and whether there are differences in exposure for each DENV serotype. We observed a significant decrease in the concentration of IgG antibodies at least 40 days after returning to an "Ae. aegypti-free" area. In addition, we found significantly higher anti-SGE IgG concentrations in DENV positive patients with some difference in exposure to mosquito bites among DENV serotypes. We conclude that the concentration of IgG antibodies against SGE is an accurate indicator of risk of dengue virus transmission and disease presence.
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Affiliation(s)
- Berlin Londono-Renteria
- Louisiana State University, Baton Rouge, Louisiana, United States of America
- Universidad de Pamplona, Pamplona, Colombia
| | - Jenny C. Cardenas
- Hospital Municipal de Los Patios, Los Patios- Norte de Santander, Colombia
| | | | | | | | - Dawn M. Wesson
- Tulane University, New Orleans, Louisiana, United States of America
| | | | | | - Christopher N. Mores
- Louisiana State University, Baton Rouge, Louisiana, United States of America
- * E-mail:
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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] [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] [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] [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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Ali ZMI, Bakli M, Fontaine A, Bakkali N, Vu Hai V, Audebert S, Boublik Y, Pagès F, Remoué F, Rogier C, Fraisier C, Almeras L. Assessment of Anopheles salivary antigens as individual exposure biomarkers to species-specific malaria vector bites. Malar J 2012; 11:439. [PMID: 23276246 PMCID: PMC3547717 DOI: 10.1186/1475-2875-11-439] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 12/19/2012] [Indexed: 01/08/2023] Open
Abstract
Background Malaria transmission occurs during the blood feeding of infected anopheline mosquitoes concomitant with a saliva injection into the vertebrate host. In sub-Saharan Africa, most malaria transmission is due to Anopheles funestus s.s and to Anopheles gambiae s.l. (mainly Anopheles gambiae s.s. and Anopheles arabiensis). Several studies have demonstrated that the immune response against salivary antigens could be used to evaluate individual exposure to mosquito bites. The aim of this study was to assess the use of secreted salivary proteins as specific biomarkers of exposure to An. gambiae and/or An. funestus bites. Methods For this purpose, salivary gland proteins 6 (SG6) and 5′nucleotidases (5′nuc) from An. gambiae (gSG6 and g-5′nuc) and An. funestus (fSG6 and f-5′nuc) were selected and produced in recombinant form. The specificity of the IgG response against these salivary proteins was tested using an ELISA with sera from individuals living in three Senegalese villages (NDiop, n = 50; Dielmo, n = 38; and Diama, n = 46) that had been exposed to distinct densities and proportions of the Anopheles species. Individuals who had not been exposed to these tropical mosquitoes were used as controls (Marseille, n = 45). Results The IgG responses against SG6 recombinant proteins from these two Anopheles species and against g-5′nucleotidase from An. gambiae, were significantly higher in Senegalese individuals compared with controls who were not exposed to specific Anopheles species. Conversely, an association was observed between the level of An. funestus exposure and the serological immune response levels against the f-5′nucleotidase protein. Conclusion This study revealed an Anopheles salivary antigenic protein that could be considered to be a promising antigenic marker to distinguish malaria vector exposure at the species level. The epidemiological interest of such species-specific antigenic markers is discussed.
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Affiliation(s)
- Zakia M I Ali
- Unité de recherche en biologie et épidémiologie parasitaires, Armed Forces Biomedical Research Institute, antenne Marseille, GSBdD de Marseille Aubagne, 111 avenue de la corse, Marseille cedex 02, France
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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] [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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Fontaine A, Fusaï T, Briolant S, Buffet S, Villard C, Baudelet E, Pophillat M, Granjeaud S, Rogier C, Almeras L. Anopheles salivary gland proteomes from major malaria vectors. BMC Genomics 2012; 13:614. [PMID: 23148599 PMCID: PMC3542285 DOI: 10.1186/1471-2164-13-614] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2012] [Accepted: 10/29/2012] [Indexed: 01/29/2023] Open
Abstract
Background Antibody responses against Anopheles salivary proteins can indicate individual exposure to bites of malaria vectors. The extent to which these salivary proteins are species-specific is not entirely resolved. Thus, a better knowledge of the diversity among salivary protein repertoires from various malaria vector species is necessary to select relevant genus-, subgenus- and/or species-specific salivary antigens. Such antigens could be used for quantitative (mosquito density) and qualitative (mosquito species) immunological evaluation of malaria vectors/host contact. In this study, salivary gland protein repertoires (sialomes) from several Anopheles species were compared using in silico analysis and proteomics. The antigenic diversity of salivary gland proteins among different Anopheles species was also examined. Results In silico analysis of secreted salivary gland protein sequences retrieved from an NCBInr database of six Anopheles species belonging to the Cellia subgenus (An. gambiae, An. arabiensis, An. stephensi and An. funestus) and Nyssorhynchus subgenus (An. albimanus and An. darlingi) displayed a higher degree of similarity compared to salivary proteins from closely related Anopheles species. Additionally, computational hierarchical clustering allowed identification of genus-, subgenus- and species-specific salivary proteins. Proteomic and immunoblot analyses performed on salivary gland extracts from four Anopheles species (An. gambiae, An. arabiensis, An. stephensi and An. albimanus) indicated that heterogeneity of the salivary proteome and antigenic proteins was lower among closely related anopheline species and increased with phylogenetic distance. Conclusion This is the first report on the diversity of the salivary protein repertoire among species from the Anopheles genus at the protein level. This work demonstrates that a molecular diversity is exhibited among salivary proteins from closely related species despite their common pharmacological activities. The involvement of these proteins as antigenic candidates for genus-, subgenus- or species-specific immunological evaluation of individual exposure to Anopheles bites is discussed.
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Affiliation(s)
- Albin Fontaine
- Unité de Parasitologie - UMR6236, URMITE - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), BP 60109, Marseille Cedex 07, 13 262, 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] [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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Drame PM, Machault V, Diallo A, Cornélie S, Poinsignon A, Lalou R, Sembène M, Dos Santos S, Rogier C, Pagès F, Le Hesran JY, Remoué F. IgG responses to the gSG6-P1 salivary peptide for evaluating human exposure to Anopheles bites in urban areas of Dakar region, Sénégal. Malar J 2012; 11:72. [PMID: 22424570 PMCID: PMC3337805 DOI: 10.1186/1475-2875-11-72] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 03/16/2012] [Indexed: 11/28/2022] Open
Abstract
Background Urban malaria can be a serious public health problem in Africa. Human-landing catches of mosquitoes, a standard entomological method to assess human exposure to malaria vector bites, can lack sensitivity in areas where exposure is low. A simple and highly sensitive tool could be a complementary indicator for evaluating malaria exposure in such epidemiological contexts. The human antibody response to the specific Anopheles gSG6-P1 salivary peptide have been described as an adequate tool biomarker for a reliable assessment of human exposure level to Anopheles bites. The aim of this study was to use this biomarker to evaluate the human exposure to Anopheles mosquito bites in urban settings of Dakar (Senegal), one of the largest cities in West Africa, where Anopheles biting rates and malaria transmission are supposed to be low. Methods One cross-sectional study concerning 1,010 (505 households) children (n = 505) and adults (n = 505) living in 16 districts of downtown Dakar and its suburbs was performed from October to December 2008. The IgG responses to gSG6-P1 peptide have been assessed and compared to entomological data obtained in or near the same district. Results Considerable individual variations in anti-gSG6-P1 IgG levels were observed between and within districts. In spite of this individual heterogeneity, the median level of specific IgG and the percentage of immune responders differed significantly between districts. A positive and significant association was observed between the exposure levels to Anopheles gambiae bites, estimated by classical entomological methods, and the median IgG levels or the percentage of immune responders measuring the contact between human populations and Anopheles mosquitoes. Interestingly, immunological parameters seemed to better discriminate the exposure level to Anopheles bites between different exposure groups of districts. Conclusions Specific human IgG responses to gSG6-P1 peptide biomarker represent, at the population and individual levels, a credible new alternative tool to assess accurately the heterogeneity of exposure level to Anopheles bites and malaria risk in low urban transmission areas. The development of such biomarker tool would be particularly relevant for mapping and monitoring malaria risk and for measuring the efficiency of vector control strategies in these specific settings.
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Affiliation(s)
- Papa M Drame
- Unité Mixte de Recherche MIVEGEC (IRD 224-CNRS 5290-UM1), Institut de Recherche pour le Développement, 34394, Montpellier Cedex 8, France.
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Evaluation of the human IgG antibody response to Aedes albopictus saliva as a new specific biomarker of exposure to vector bites. PLoS Negl Trop Dis 2012; 6:e1487. [PMID: 22363823 PMCID: PMC3283547 DOI: 10.1371/journal.pntd.0001487] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Accepted: 11/30/2011] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND The spread of Aedes albopictus, a vector for re-emergent arbovirus diseases like chikungunya and dengue, points up the need for better control strategies and new tools to evaluate transmission risk. Human antibody (Ab) responses to mosquito salivary proteins could represent a reliable biomarker for evaluating human-vector contact and the efficacy of control programs. METHODOLOGY/PRINCIPAL FINDINGS We used ELISA tests to evaluate specific immunoglobulin G (IgG) responses to salivary gland extracts (SGE) in adults exposed to Aedes albopictus in Reunion Island. The percentage of immune responders (88%) and levels of anti-SGE IgG Abs were high in exposed individuals. At an individual level, our results indicate heterogeneity of the exposure to Aedes albopictus bites. In addition, low-level immune cross-reactivity between Aedes albopictus and Aedes aegypti SGEs was observed, mainly in the highest responders. CONCLUSION/SIGNIFICANCE Ab responses to saliva could be used as an immuno-epidemiological tool for evaluating exposure to Aedes albopictus bites. Combined with entomological and epidemiological methods, a "salivary" biomarker of exposure to Aedes albopictus could enhance surveillance of its spread and the risk of arbovirus transmission, and could be used as a direct tool for the evaluation of Aedes albopictus control strategies.
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Fontaine A, Pascual A, Orlandi-Pradines E, Diouf I, Remoué F, Pagès F, Fusaï T, Rogier C, Almeras L. Relationship between exposure to vector bites and antibody responses to mosquito salivary gland extracts. PLoS One 2011; 6:e29107. [PMID: 22195000 PMCID: PMC3237593 DOI: 10.1371/journal.pone.0029107] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Accepted: 11/21/2011] [Indexed: 11/23/2022] Open
Abstract
Mosquito-borne diseases are major health problems worldwide. Serological responses to mosquito saliva proteins may be useful in estimating individual exposure to bites from mosquitoes transmitting these diseases. However, the relationships between the levels of these IgG responses and mosquito density as well as IgG response specificity at the genus and/or species level need to be clarified prior to develop new immunological markers to assess human/vector contact. To this end, a kinetic study of antibody levels against several mosquito salivary gland extracts from southeastern French individuals living in three areas with distinct ecological environments and, by implication, distinct Aedes caspius mosquito densities were compared using ELISA. A positive association was observed between the average levels of IgG responses against Ae. caspius salivary gland extracts and spatial Ae. caspius densities. Additionally, the average level of IgG responses increased significantly during the peak exposure to Ae. caspius at each site and returned to baseline four months later, suggesting short-lived IgG responses. The species-specificity of IgG antibody responses was determined by testing antibody responses to salivary gland extracts from Cx. pipiens, a mosquito that is present at these three sites at different density levels, and from two other Aedes species not present in the study area (Ae. aegypti and Ae. albopictus). The IgG responses observed against these mosquito salivary gland extracts contrasted with those observed against Ae. caspius salivary gland extracts, supporting the existence of species-specific serological responses. By considering different populations and densities of mosquitoes linked to environmental factors, this study shows, for the first time, that specific IgG antibody responses against Ae. caspius salivary gland extracts may be related to the seasonal and geographical variations in Ae. caspius density. Characterisation of such immunological-markers may allow the evaluation of the effectiveness of vector-control strategies or estimation of the risk of vector-borne disease transmission.
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Affiliation(s)
- Albin Fontaine
- Unité de Parasitologie, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France
| | - Aurélie Pascual
- Unité de Parasitologie, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France
| | - Eve Orlandi-Pradines
- Unité d'Entomologie Médicale, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France
| | - Ibrahima Diouf
- Unité de Parasitologie, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France
| | - Franck Remoué
- Caractérisation des Populations de vecteurs, Institut de Recherche pour le Développement (IRD), Montpellier, France
| | - Frédéric Pagès
- Unité d'Entomologie Médicale, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France
| | - Thierry Fusaï
- Unité de Parasitologie, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France
| | - Christophe Rogier
- Unité de Parasitologie, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France
- Institut Pasteur de Madagascar, Antananarivo, Madagascar
| | - Lionel Almeras
- Unité de Parasitologie, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France
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Fontaine A, Diouf I, Bakkali N, Missé D, Pagès F, Fusai T, Rogier C, Almeras L. Implication of haematophagous arthropod salivary proteins in host-vector interactions. Parasit Vectors 2011; 4:187. [PMID: 21951834 PMCID: PMC3197560 DOI: 10.1186/1756-3305-4-187] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Accepted: 09/28/2011] [Indexed: 01/25/2023] Open
Abstract
The saliva of haematophagous arthropods contains an array of anti-haemostatic, anti-inflammatory and immunomodulatory molecules that contribute to the success of the blood meal. The saliva of haematophagous arthropods is also involved in the transmission and the establishment of pathogens in the host and in allergic responses. This survey provides a comprehensive overview of the pharmacological activity and immunogenic properties of the main salivary proteins characterised in various haematophagous arthropod species. The potential biological and epidemiological applications of these immunogenic salivary molecules will be discussed with an emphasis on their use as biomarkers of exposure to haematophagous arthropod bites or vaccine candidates that are liable to improve host protection against vector-borne diseases.
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Affiliation(s)
- Albin Fontaine
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Ibrahima Diouf
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Nawal Bakkali
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Dorothée Missé
- Laboratoire de Génétique et Evolution des Maladies infectieuses, UMR 2724 CNRS/IRD, Montpellier, France
| | - Frédéric Pagès
- Unité d'Entomologie Médicale, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Thierry Fusai
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Christophe Rogier
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
- Institut Pasteur de Madagascar, B.P. 1274, Ambohitrakely, 101 Antananarivo, Madagascar
| | - Lionel Almeras
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
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Gidwani K, Picado A, Rijal S, Singh SP, Roy L, Volfova V, Andersen EW, Uranw S, Ostyn B, Sudarshan M, Chakravarty J, Volf P, Sundar S, Boelaert M, Rogers ME. Serological markers of sand fly exposure to evaluate insecticidal nets against visceral leishmaniasis in India and Nepal: a cluster-randomized trial. PLoS Negl Trop Dis 2011; 5:e1296. [PMID: 21931871 PMCID: PMC3172194 DOI: 10.1371/journal.pntd.0001296] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 07/16/2011] [Indexed: 12/02/2022] Open
Abstract
Background Visceral leishmaniasis is the world' second largest vector-borne parasitic killer and a neglected tropical disease, prevalent in poor communities. Long-lasting insecticidal nets (LNs) are a low cost proven vector intervention method for malaria control; however, their effectiveness against visceral leishmaniasis (VL) is unknown. This study quantified the effect of LNs on exposure to the sand fly vector of VL in India and Nepal during a two year community intervention trial. Methods As part of a paired-cluster randomized controlled clinical trial in VL-endemic regions of India and Nepal we tested the effect of LNs on sand fly biting by measuring the antibody response of subjects to the saliva of Leishmania donovani vector Phlebotomus argentipes and the sympatric (non-vector) Phlebotomus papatasi. Fifteen to 20 individuals above 15 years of age from 26 VL endemic clusters were asked to provide a blood sample at baseline, 12 and 24 months post-intervention. Results A total of 305 individuals were included in the study, 68 participants provided two blood samples and 237 gave three samples. A random effect linear regression model showed that cluster-wide distribution of LNs reduced exposure to P. argentipes by 12% at 12 months (effect 0.88; 95% CI 0.83–0.94) and 9% at 24 months (effect 0.91; 95% CI 0.80–1.02) in the intervention group compared to control adjusting for baseline values and pair. Similar results were obtained for P. papatasi. Conclusions This trial provides evidence that LNs have a limited effect on sand fly exposure in VL endemic communities in India and Nepal and supports the use of sand fly saliva antibodies as a marker to evaluate vector control interventions. Visceral leishmaniasis (VL), also known as kala azar, is one of the major public health concerns of the Indian subcontinent, caused by Leishmania donovani transmitted by the bite of the sand fly Phlebotomus argentipes. To date, Indoor Residual Spraying (IRS) campaigns have been unable to control the disease. This makes Long-lasting insecticidal nets (LNs) an attractive alternative or complement to IRS. Therefore, it is important to assess the extent that LNs reduce bites from P. argentipes. When female sand flies bite they require their saliva to efficiently bloodfeed. For humans and animals alike, the host' immune response against components of sand fly saliva can be used as a marker of exposure to the vector. Here we describe how comprehensive coverage of LNs in trial communities over two years reduced antibody levels to the saliva of P. argentipes and P. papatasi (a man-biting sand fly that co-exists with P. argentipes but does not transmit VL) sand flies by 9–12% compared to communities without LNs. Our results demonstrate that the large-scale distribution of LNs did not confer significant additional protection against sand fly bites in VL-endemic regions of India and Nepal and questions the indoor transmission of L. donovani in these regions.
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Affiliation(s)
| | - Albert Picado
- London School of Hygiene and Tropical Medicine, London, United Kingdom
- Institute of Tropical Medicine, Antwerp, Belgium
| | - Suman Rijal
- BP Koirala Institute of Health Sciences, Dharan, Nepal
| | | | - Lalita Roy
- BP Koirala Institute of Health Sciences, Dharan, Nepal
| | | | - Elisabeth Wreford Andersen
- London School of Hygiene and Tropical Medicine, London, United Kingdom
- University of Copenhagen, Copenhagen, Denmark
| | | | - Bart Ostyn
- Institute of Tropical Medicine, Antwerp, Belgium
| | | | | | - Petr Volf
- Charles University, Prague, Czech Republic
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Rizzo C, Ronca R, Fiorentino G, Mangano VD, Sirima SB, Nèbiè I, Petrarca V, Modiano D, Arcà B. Wide cross-reactivity between Anopheles gambiae and Anopheles funestus SG6 salivary proteins supports exploitation of gSG6 as a marker of human exposure to major malaria vectors in tropical Africa. Malar J 2011; 10:206. [PMID: 21794142 PMCID: PMC3160432 DOI: 10.1186/1475-2875-10-206] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 07/27/2011] [Indexed: 11/21/2022] Open
Abstract
Background The Anopheles gambiae gSG6 is an anopheline-specific salivary protein which helps female mosquitoes to efficiently feed on blood. Besides its role in haematophagy, gSG6 is immunogenic and elicits in exposed individuals an IgG response, which may be used as indicator of exposure to the main African malaria vector A. gambiae. However, malaria transmission in tropical Africa is sustained by three main vectors (A. gambiae, Anopheles arabiensis and Anopheles funestus) and a general marker, reflecting exposure to at least these three species, would be especially valuable. The SG6 protein is highly conserved within the A. gambiae species complex whereas the A. funestus homologue, fSG6, is more divergent (80% identity with gSG6). The aim of this study was to evaluate cross-reactivity of human sera to gSG6 and fSG6. Methods The A. funestus SG6 protein was expressed/purified and the humoral response to gSG6, fSG6 and a combination of the two antigens was compared in a population from a malaria hyperendemic area of Burkina Faso where both vectors were present, although with a large A. gambiae prevalence (>75%). Sera collected at the beginning and at the end of the high transmission/rainy season, as well as during the following low transmission/dry season, were analysed. Results According to previous observations, both anti-SG6 IgG level and prevalence decreased during the low transmission/dry season and showed a typical age-dependent pattern. No significant difference in the response to the two antigens was found, although their combined use yielded in most cases higher IgG level. Conclusions Comparative analysis of gSG6 and fSG6 immunogenicity to humans suggests the occurrence of a wide cross-reactivity, even though the two proteins carry species-specific epitopes. This study supports the use of gSG6 as reliable indicator of exposure to the three main African malaria vectors, a marker which may be useful to monitor malaria transmission and evaluate vector control measures, especially in conditions of low malaria transmission and/or reduced vector density. The Anopheles stephensi SG6 protein also shares 80% identity with gSG6, suggesting the attractive possibility that the A. gambiae protein may also be useful to assess human exposure to several Asian malaria vectors.
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Affiliation(s)
- Cinzia Rizzo
- Department of Public Health and Infectious Diseases, Sapienza University, P.le Aldo Moro 5, 00185 Rome, Italy
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Schwarz A, Juarez JA, Richards J, Rath B, Machaca VQ, Castro YE, Málaga ES, Levy K, Gilman RH, Bern C, Verastegui M, Levy MZ. Anti-triatomine saliva immunoassays for the evaluation of impregnated netting trials against Chagas disease transmission. Int J Parasitol 2011; 41:591-4. [PMID: 21426907 DOI: 10.1016/j.ijpara.2011.02.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Revised: 02/16/2011] [Accepted: 02/17/2011] [Indexed: 10/18/2022]
Abstract
Insecticide-impregnated nets can kill triatomine bugs, but it remains unclear whether they can protect against Chagas disease transmission. In a field trial in Quequeña, Peru, sentinel guinea pigs placed in intervention enclosures covered by deltamethrin-treated nets showed significantly lower antibody responses to saliva of Triatoma infestans compared with animals placed in pre-existing control enclosures. Our results strongly suggest that insecticide-treated nets prevent triatomine bites and can thereby protect against infection with Trypanosoma cruzi. Anti-salivary immunoassays are powerful new tools to evaluate intervention strategies against Chagas disease.
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Affiliation(s)
- Alexandra Schwarz
- Laboratory of Genomics and Proteomics of Disease Vectors, Institute of Parasitology, Biology Centre of the Academy of Sciences of Czech Republic, České Budĕjovice, Czech Republic
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