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Howell MM, Olajiga OM, Cardenas JC, Parada-Higuera CA, Gonzales-Pabon MU, Gutierrez-Silva LY, Jaimes-Villamizar L, Werner BM, Shaffer JG, Manuzak JA, Londono-Renteria B. Mosquito Salivary Antigens and Their Relationship to Dengue and P. vivax Malaria. Pathogens 2024; 13:52. [PMID: 38251359 PMCID: PMC10818852 DOI: 10.3390/pathogens13010052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/10/2023] [Accepted: 12/27/2023] [Indexed: 01/23/2024] Open
Abstract
In tropical areas, the simultaneous transmission of multiple vector-borne diseases is common due to ecological factors shared by arthropod vectors. Malaria and dengue virus, transmitted by Anopheles and Aedes mosquitoes, respectively, are among the top vector-borne diseases that cause significant morbidity and mortality in endemic areas. Notably, tropical areas often have suitable conditions for the co-existence of these mosquito species, highlighting the importance of identifying markers that accurately indicate the risk of acquiring each specific disease entity. Aedes are daytime-biting mosquitoes, while Anopheles preferentially bite during the night. These biting patterns raise the possibility of concurrent exposure to bites from both species. This is important because mosquito saliva, deposited in the skin during blood feeding, induces immune responses that modulate pathogen establishment and infection. Previous studies have focused on characterizing such effects on the vector-pathogen interface for an individual pathogen and its mosquito vector. In this study, we evaluated associations between immune responses to salivary proteins from non-dengue and non-malaria vector mosquito species with clinical characteristics of malaria and dengue, respectively. Surprisingly, antibody responses against Anopheles antigens in dengue patients correlated with red blood cell count and hematocrit, while antibody responses against Aedes proteins were associated with platelet count in malaria patients. Our data indicate that concurrent exposure to multiple disease-carrying mosquito vectors and their salivary proteins with differing immunomodulatory properties could influence the transmission, pathogenesis, and clinical presentation of malaria, dengue fever, and other vector-borne illnesses.
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Affiliation(s)
- McKenna M. Howell
- Arbovirology Laboratory, Department of Tropical Medicine and Infectious Disease, Tulane University, New Orleans, LA 70112, USA; (M.M.H.); (J.C.C.)
| | - Olayinka M. Olajiga
- Arbovirology Laboratory, Department of Tropical Medicine and Infectious Disease, Tulane University, New Orleans, LA 70112, USA; (M.M.H.); (J.C.C.)
| | - Jenny C. Cardenas
- Arbovirology Laboratory, Department of Tropical Medicine and Infectious Disease, Tulane University, New Orleans, LA 70112, USA; (M.M.H.); (J.C.C.)
| | | | | | | | | | - Brett M. Werner
- College of Science and Technology, Bellevue University, Bellevue, NE 68005, USA;
| | - Jeffrey G. Shaffer
- Department of Biostatistics and Data Science, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA 70112, USA;
| | - Jennifer A. Manuzak
- Division of Immunology, Tulane National Primate Research Center, Covington, LA 70433, USA;
| | - Berlin Londono-Renteria
- Arbovirology Laboratory, Department of Tropical Medicine and Infectious Disease, Tulane University, New Orleans, LA 70112, USA; (M.M.H.); (J.C.C.)
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Padonou GG, Konkon AK, Salako AS, Zoungbédji DM, Ossè R, Sovi A, Azondekon R, Sidick A, Ahouandjinou JM, Adoha CJ, Sominahouin AA, Tokponnon FT, Akinro B, Sina H, Baba-Moussa L, Akogbéto MC. Distribution and Abundance of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in Benin, West Africa. Trop Med Infect Dis 2023; 8:439. [PMID: 37755900 PMCID: PMC10535150 DOI: 10.3390/tropicalmed8090439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 08/30/2023] [Accepted: 09/05/2023] [Indexed: 09/28/2023] Open
Abstract
Updated information on the distribution and abundance of Aedes aegypti and Aedes albopictus is crucial to prepare African countries, such as Benin, for possible arboviral disease outbreaks. This study aims to evaluate the geographical distribution, abundance and biting behaviour of these two vectors in Benin. Three sampling techniques were used in this study. The collection of Aedes spp. adults were made through human landing catch (HLC), immatures were captured with the use of ovitraps, and a dipping technique was used for the collection of Aedes spp. in 23 communes located along the North-South and East-West transect of Benin. Adult Aedes mosquitoes were collected indoors and outdoors using HLC. Mosquito eggs, larvae and pupae were collected from containers and ovitraps. The adult mosquitoes were morphologically identified, then confirmed using a polymerase chain reaction (PCR). Overall, 12,424 adult specimens of Aedes spp. were collected, out of which 76.53% (n = 9508) and 19.32% (n = 2400) were morphologically identified as Ae. aegypti and Ae. albopictus, respectively. Geographically, Ae. aegypti was found across the North-South transect unlike Ae. albopictus, which was only encountered in the southern part of the country, with a great preponderance in Avrankou. Furthermore, an exophagic behaviour was observed in both vectors. This updated distribution of Aedes mosquito species in Benin will help to accurately identify areas that are at risk of arboviral diseases and better plan for future vector control interventions.
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Affiliation(s)
- Germain Gil Padonou
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
- Laboratory of Biology and Molecular Typing in Microbiology, Department of Biochemistry and Cellular Biology, Faculty of Sciences and Techniques, University of Abomey-Calavi, Cotonou 05 BP 1604, Benin; (H.S.); (L.B.-M.)
| | - Alphonse Keller Konkon
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
- Laboratory of Biology and Molecular Typing in Microbiology, Department of Biochemistry and Cellular Biology, Faculty of Sciences and Techniques, University of Abomey-Calavi, Cotonou 05 BP 1604, Benin; (H.S.); (L.B.-M.)
| | - Albert Sourou Salako
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
| | - David Mahouton Zoungbédji
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
- Laboratory of Biology and Molecular Typing in Microbiology, Department of Biochemistry and Cellular Biology, Faculty of Sciences and Techniques, University of Abomey-Calavi, Cotonou 05 BP 1604, Benin; (H.S.); (L.B.-M.)
| | - Razaki Ossè
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
- École de Gestion et d’Exploitation des Systèmes d’Élevage, Université Nationale d’Agriculture de Porto-Novo, Porto-Novo 01 BP 55, Benin
| | - Arthur Sovi
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
- Faculty of Agronomy, University of Parakou, Parakou BP 123, Benin
- Faculty of Infectious and Tropical Diseases, Disease Control Department, The London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Roseric Azondekon
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
| | - Aboubakar Sidick
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
| | - Juvénal Minassou Ahouandjinou
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
- Laboratory of Biology and Molecular Typing in Microbiology, Department of Biochemistry and Cellular Biology, Faculty of Sciences and Techniques, University of Abomey-Calavi, Cotonou 05 BP 1604, Benin; (H.S.); (L.B.-M.)
| | - Constantin Jesukèdè Adoha
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
- Laboratory of Biology and Molecular Typing in Microbiology, Department of Biochemistry and Cellular Biology, Faculty of Sciences and Techniques, University of Abomey-Calavi, Cotonou 05 BP 1604, Benin; (H.S.); (L.B.-M.)
| | - André Aimé Sominahouin
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
| | - Filémon Tatchémè Tokponnon
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
| | - Bruno Akinro
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
| | - Haziz Sina
- Laboratory of Biology and Molecular Typing in Microbiology, Department of Biochemistry and Cellular Biology, Faculty of Sciences and Techniques, University of Abomey-Calavi, Cotonou 05 BP 1604, Benin; (H.S.); (L.B.-M.)
| | - Lamine Baba-Moussa
- Laboratory of Biology and Molecular Typing in Microbiology, Department of Biochemistry and Cellular Biology, Faculty of Sciences and Techniques, University of Abomey-Calavi, Cotonou 05 BP 1604, Benin; (H.S.); (L.B.-M.)
| | - Martin Codjo Akogbéto
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou 06 BP 2604, Benin; (A.K.K.); (A.S.S.); (D.M.Z.); (R.O.); (R.A.); (A.S.); (J.M.A.); (C.J.A.); (A.A.S.); (F.T.T.); (B.A.); (M.C.A.)
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Sri-In C, Thontiravong A, Bartholomay LC, Wechtaisong W, Thongmeesee K, Riana E, Tiawsirisup S. 34-kDa salivary protein enhances duck Tembusu virus infectivity in the salivary glands of Aedes albopictus by modulating the innate immune response. Sci Rep 2023; 13:9098. [PMID: 37277542 DOI: 10.1038/s41598-023-35914-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 05/25/2023] [Indexed: 06/07/2023] Open
Abstract
Duck Tembusu virus (DTMUV) is an important flavivirus that can be transmitted to poultry via Aedes albopictus bites. Furthermore, humans residing in the DTMUV epidemic area display activated antiviral immune responses to local DTMUV isolates during the pathogenic invasion, thereby raising the primary concern that this flavivirus may be transmitted to humans via mosquito bites. Therefore, we identified the gene AALF004421, which is a homolog of the 34-kDa salivary protein (34 kDa) of Ae. albopictus and studied the salivary protein-mediated enhancement of DTMUV infection in Ae. albopictus salivary glands. We observed that double-stranded RNA-mediated silencing of the 34 kDa in mosquito salivary glands demonstrated that the silenced 34 kDa impaired DTMUV infectivity, similar to inhibition through serine protease. This impairment occurred as a consequence of triggering the innate immune response function of a macroglobulin complement-related factor (MCR). 34-kDa in the salivary gland which had similar activity as a serine protease, results in the abrogation of antimicrobial peptides production and strong enhance DTMUV replication and transmission. Although the function of the 34 kDa in Ae. albopictus is currently unknown; in the present study, we showed that it may have a major role in DTMUV infection in mosquito salivary glands through the suppression of the antiviral immune response in the earliest stages of infection. This finding provides the first identification of a prominently expressed 34 kDa protein in Ae. albopictus saliva that could serve as a target for controlling DTMUV replication in mosquito vectors.
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Affiliation(s)
- Chalida Sri-In
- Animal Vector-Borne Disease Research Unit, Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Aunyaratana Thontiravong
- Animal Vector-Borne Disease Research Unit, Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand
| | - Lyric C Bartholomay
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Wisconsin, USA
| | - Wittawat Wechtaisong
- Animal Vector-Borne Disease Research Unit, Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Kritsada Thongmeesee
- Animal Vector-Borne Disease Research Unit, Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Elizabeth Riana
- Animal Vector-Borne Disease Research Unit, Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Sonthaya Tiawsirisup
- Animal Vector-Borne Disease Research Unit, Veterinary Parasitology Unit, Department of Veterinary Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
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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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Kassam NA, Laswai D, Kulaya N, Kaaya RD, Kajeguka DC, Schmiegelow C, Wang CW, Alifrangis M, Kavishe RA. Human IgG responses to Aedes mosquito salivary peptide Nterm-34kDa and its comparison to Anopheles salivary antigen (gSG6-P1) IgG responses measured among individuals living in Lower Moshi, Tanzania. PLoS One 2022; 17:e0276437. [PMID: 36301860 PMCID: PMC9612500 DOI: 10.1371/journal.pone.0276437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 09/13/2022] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND The level of human exposure to arbovirus vectors, the Aedes mosquitoes, is mainly assessed by entomological methods which are labour intensive, difficult to sustain at a large scale and are affected if transmission and exposure levels are low. Alternatively, serological biomarkers which detect levels of human exposure to mosquito bites may complement the existing epidemiologic tools as they seem cost-effective, simple, rapid, and sensitive. This study explored human IgG responses to an Aedes mosquito salivary gland peptide Nterm-34kDa in Lower Moshi, a highland area with evidence of circulating arboviruses and compared the Aedes IgG responses to Anopheles mosquitoes' salivary antigen (GSG6-P1) IgG responses. METHODS Three cross-sectional surveys were conducted in 2019: during the first dry season in March, at the end of the rainy season in June and during the second dry season in September in five villages located in Lower Moshi. Blood samples were collected from enrolled participants above six months of age (age span: 7 months to 94 years) and analysed for the presence of anti-Nterm-34kDa IgG antibodies. Possible associations between Nterm-34kDa seroprevalence and participants' characteristics were determined. Levels of IgG responses and seroprevalence were correlated and compared to the already measured IgG responses and seroprevalence of Anopheles mosquitoes' salivary antigen, GSG6-P1. RESULTS During the first dry season, Nterm-34kDa seroprevalence was 34.1% and significantly increased at the end of the rainy season to 45.3% (Chi square (χ2) = 6.42 p = 0.011). During the second dry season, the seroprevalence significantly declined to 26.5% (χ2 = 15.12 p<0.001). During the rainy season, seroprevalence was significantly higher among residents of Oria village (adjusted odds ratio (AOR) = 2.86; 95% CI = 1.0-7.8; p = 0.041) compared to Newland. Moreover, during the rainy season, the risk of exposure was significantly lower among individuals aged between 16 and 30 years (AOR = 0.25; 95% CI = 0.1 = 0.9; p = 0.036) compared to individuals aged between 0 and 5 years. There was weak to moderate negative correlation between N-term 34kDa IgG and gSG6-P1 antigens. N-term 34kDa seroprevalence were higher compared to gSG6-P1 seroprevalence. CONCLUSION The findings of this study support that IgG antibody responses towards the Aedes mosquito salivary peptide Nterm-34kDa are detectable among individuals living in lower Moshi and vary with season and geographical area. More individuals are exposed to Aedes mosquito bites than Anopheles mosquito and those exposed to Aedes bites are not necessarily exposed to Anopheles mosquitoes.
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Affiliation(s)
- Nancy A. Kassam
- Kilimanjaro Christian Medical University College (KCMUCo), Moshi, Tanzania
- * E-mail:
| | - Daniel Laswai
- Muhimbili University of Health and Allied Sciences (MUHAS), Dar es Salaam, Tanzania
| | - Neema Kulaya
- Kilimanjaro Christian Medical University College (KCMUCo), Moshi, Tanzania
| | - Robert D. Kaaya
- Kilimanjaro Christian Medical University College (KCMUCo), Moshi, Tanzania
- Pan-African Malaria Vector Research Consortium, Moshi, Tanzania
| | - Debora C. Kajeguka
- Kilimanjaro Christian Medical University College (KCMUCo), Moshi, Tanzania
| | - Christentze Schmiegelow
- Centre for Medical Parasitology, Department of Immunology and Microbiology, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Christian W. Wang
- Centre for Medical Parasitology, Department of Immunology and Microbiology, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Michael Alifrangis
- Centre for Medical Parasitology, Department of Immunology and Microbiology, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
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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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Human IgG responses to the Aedes albopictus 34k2 salivary protein: analyses in Réunion Island and Bolivia confirm its suitability as marker of host exposure to the tiger mosquito. Parasit Vectors 2022; 15:260. [PMID: 35858924 PMCID: PMC9301888 DOI: 10.1186/s13071-022-05383-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 07/06/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The rapid worldwide spreading of Aedes aegypti and Aedes albopictus is expanding the risk of arboviral diseases transmission, pointing out the urgent need to improve monitoring and control of mosquito vector populations. Assessment of human-vector contact, currently estimated by classical entomological methods, is crucial to guide planning and implementation of control measures and evaluate transmission risk. Antibody responses to mosquito genus-specific salivary proteins are emerging as a convenient complementary tool for assessing host exposure to vectors. We previously showed that IgG responses to the Ae. albopictus 34k2 salivary protein (al34k2) allow detection of seasonal and geographic variation of human exposure to the tiger mosquito in two temperate areas of Northeast Italy. The main aim of this study was to confirm and extend these promising findings to tropical areas with ongoing arboviral transmission. METHODS IgG responses to al34k2 and to the Ae. aegypti orthologous protein ae34k2 were measured by ELISA in cohorts of subjects only exposed to Ae. albopictus (Réunion Island), only exposed to Ae. aegypti (Bolivia) or unexposed to both these vectors (North of France). RESULTS AND CONCLUSION Anti-al34k2 IgG levels were significantly higher in sera of individuals from Réunion Island than in unexposed controls, indicating that al34k2 may be a convenient and reliable proxy for whole saliva or salivary gland extracts as an indicator of human exposure to Ae. albopictus. Bolivian subjects, exposed to bites of Ae. aegypti, carried in their sera IgG recognizing the Ae. albopictus al34k2 protein, suggesting that this salivary antigen can also detect, even though with low sensitivity, human exposure to Ae. aegypti. On the contrary, due to the high background observed in unexposed controls, the recombinant ae34k2 appeared not suitable for the evaluation of human exposure to Aedes mosquitoes. Overall, this study confirmed the suitability of anti-al34k2 IgG responses as a specific biomarker of human exposure to Ae. albopictus and, to a certain extent, to Ae. aegypti. Immunoassays based on al34k2 are expected to be especially effective in areas where Ae. albopictus is the main arboviral vector but may also be useful in areas where Ae. albopictus and Ae. aegypti coexist.
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Review of the ecology and behaviour of Aedes aegypti and Aedes albopictus in Western Africa and implications for vector control. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2022; 2:100074. [PMID: 35726222 PMCID: PMC7612875 DOI: 10.1016/j.crpvbd.2021.100074] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Western Africa is vulnerable to arboviral disease transmission, having recently experienced major outbreaks of chikungunya, dengue, yellow fever and Zika. However, there have been relatively few studies on the natural history of the two major human arbovirus vectors in this region, Aedes aegypti and Ae. albopictus, potentially limiting the implementation of effective vector control. We systematically searched for and reviewed relevant studies on the behaviour and ecology of Ae. aegypti and Ae. albopictus in Western Africa, published over the last 40 years. We identified 73 relevant studies, over half of which were conducted in Nigeria, Senegal, or Côte d'Ivoire. Most studies investigated the ecology of Ae. aegypti and Ae. albopictus, exploring the impact of seasonality and land cover on mosquito populations and identifying aquatic habitats. This review highlights the adaptation of Ae. albopictus to urban environments and its invasive potential, and the year-round maintenance of Ae. aegypti populations in water storage containers. However, important gaps were identified in the literature on the behaviour of both species, particularly Ae. albopictus. In Western Africa, Ae. aegypti and Ae. albopictus appear to be mainly anthropophilic and to bite predominantly during the day, but further research is needed to confirm this to inform planning of effective vector control strategies. We discuss the public health implications of these findings and comment on the suitability of existing and novel options for control in Western Africa.
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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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Influence of Host-Related Factors and Exposure to Mosquito Bites on the Dynamics of Antibody Response to Plasmodium falciparum Antigens. Trop Med Infect Dis 2021; 6:tropicalmed6040185. [PMID: 34698307 PMCID: PMC8544703 DOI: 10.3390/tropicalmed6040185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 09/30/2021] [Accepted: 10/11/2021] [Indexed: 11/24/2022] Open
Abstract
Humoral immunity to Plasmodium falciparum is acquired after repeated infections, and can lead to clinical protection. This study aimed to evaluate how human-, parasite-, and environment-related determinants can modulate the dynamics of IgG responses to Plasmodium falciparum after an infection. Individuals (n = 68, average age = 8.2 years) with uncomplicated malaria were treated with ACT and followed up for 42 days. IgG responses to P. falciparum merozoite antigens (PfMSP1, PfMSP3, PfAMA1, PfGLURP-R0), to whole schizont extract (PfSchz), and to Anopheles gSG6-P1 and Aedes Nterm–34 kDa salivary peptides were measured. Regression analyses were used to identify factors that influence the dynamics of IgG response to P. falciparum antigen between D0 and D42, including demographic and biological factors and the level of exposure to mosquito bites. The dynamics of IgG response to P. falciparum differed according to the antigen. According to multivariate analysis, IgG responses to PfSchz and to PfGLURP-R0 appear to be affected by exposure to Aedes saliva and are associated with age, parasite density, and anti-Plasmodium pre-existing immune response at study inclusion. The present work shows that human exposure to Aedes saliva may contribute, in addition to other factors, to the regulation of anti-Plasmodium immune responses during a natural infection.
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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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Fustec B, Phanitchat T, Aromseree S, Pientong C, Thaewnongiew K, Ekalaksananan T, Cerqueira D, Poinsignon A, Elguero E, Bangs MJ, Alexander N, Overgaard HJ, Corbel V. Serological biomarker for assessing human exposure to Aedes mosquito bites during a randomized vector control intervention trial in northeastern Thailand. PLoS Negl Trop Dis 2021; 15:e0009440. [PMID: 34043621 PMCID: PMC8189451 DOI: 10.1371/journal.pntd.0009440] [Citation(s) in RCA: 6] [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: 09/16/2020] [Revised: 06/09/2021] [Accepted: 05/04/2021] [Indexed: 01/21/2023] Open
Abstract
Background Aedes mosquitoes are vectors for several major arboviruses of public health concern including dengue viruses. The relationships between Aedes infestation and disease transmission are complex wherein the epidemiological dynamics can be difficult to discern because of a lack of robust and sensitive indicators for predicting transmission risk. This study investigates the use of anti-Aedes saliva antibodies as a serological biomarker for Aedes mosquito bites to assess small scale variations in adult Aedes density and dengue virus (DENV) transmission risk in northeastern Thailand. Individual characteristics, behaviors/occupation and socio-demographics, climatic and epidemiological risk factors associated with human-mosquito exposure are also addressed. Methods The study was conducted within a randomized clustered control trial in Roi Et and Khon Kaen provinces over a consecutive 19 months period. Thirty-six (36) clusters were selected, each of ten houses. Serological and entomological surveys were conducted in all houses every four months and monthly in three sentinel households per cluster between September 2017 and April 2019 for blood spot collections and recording concurrent immature and adult Aedes indices. Additionally, the human exposure to Aedes mosquito bites (i.e., Mosquito Exposure Index or MEI) was estimated by ELISA measuring levels of human antibody response to the specific Nterm-34 kDa salivary antigen. The relationships between the MEI, vector infestation indices (adult and immature stages) and vector DENV infection were evaluated using a two-level (house and individual levels) mixed model analysis with one-month lag autoregressive correlation. Results There was a strong positive relationship between the MEI and adult Aedes (indoor and outdoor) density. Individuals from households with a medium mosquito density (mean difference: 0.091, p<0.001) and households with a high mosquito density (mean difference: 0.131, p<0.001) had higher MEI’s compared to individuals from households without Aedes. On a similar trend, individuals from households with a low, medium or high indoor Aedes densities (mean difference: 0.021, p<0.007, 0.053, p<0.0001 and 0.037, p<0.0001 for low, medium and high levels of infestation, respectively) had higher MEI than individuals from houses without indoor Aedes. The MEI was driven by individual characteristics, such as gender, age and occupation/behaviors, and varied according to climatic, seasonal factors and vector control intervention (p<0.05). Nevertheless, the study did not demonstrate a clear correlation between MEI and the presence of DENV-infected Aedes. Conclusion This study represents an important step toward the validation of the specific IgG response to the Aedes salivary peptide Nterm-34kDa as a proxy measure for Aedes infestation levels and human-mosquito exposure risk in a dengue endemic setting. The use of the IgG response to the Nterm-34 kDa peptide as a viable diagnostic tool for estimating dengue transmission requires further investigations and validation in other geographical and transmission settings. Aedes mosquitoes and the viruses they transmit are major public health concerns for over half of the global human population. However, the quantitative relationships between virus transmission and vector mosquito infestation remain unclear despite numerous indicators used to estimate transmission risk and predict dengue outbreaks. The aim of this study is to investigate the use of a salivary biomarker to assess the small-scale variation in human exposure to Aedes bites and the risk of dengue infection in the context of a vector control intervention in northeastern Thailand. A cohort of 539 persons visited every four months, including 161 individuals visited monthly, were recruited for routine serological and concurrent household entomological surveys during 19 consecutive months follow-up. Antibody response to Aedes bites was measured by enzyme-linked immunosorbent assays to assess the mosquito exposure index (MEI) and association with the Aedes adult and immature abundance as well as the presence of dengue virus (DENV) in adult mosquitoes (transmission risk). Additionally, the individual (cohort), climatic, and vector control intervention risk factors associated with MEI are explored. This study demonstrates that the MEI was strongly related to household adult Aedes density, particularly indoors resting mosquitoes. Additionally, the MEI was influenced by individual characteristics (i.e., person age, gender, staying indoors), and varied according to seasons and intervention. Nonetheless, no clear relationship between MEI and dengue transmission risk (i.e., vector infection) was detected. This study demonstrated the potential usefulness of the MEI to assess heterogeneity in adult Aedes infestation indices that could assist public health authorities to rapidly identify mosquito “hot spots” and the timeliness of effective vector control interventions.
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Affiliation(s)
- Benedicte Fustec
- Univ Montpellier, Montpellier, France
- Khon Kaen University, Khon Kaen, Thailand
- MIVEGEC, Univ Montpellier, IRD, CNRS, Montpellier, France
- * E-mail: (BF); (VC)
| | - Thipruethai Phanitchat
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok
| | - Sirinart Aromseree
- Khon Kaen University, Khon Kaen, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Chamsai Pientong
- Khon Kaen University, Khon Kaen, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | | | - Tipaya Ekalaksananan
- Khon Kaen University, Khon Kaen, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Dominique Cerqueira
- Public Health & Malaria Control, International SOS, Mimika, Papua, Indonesia
| | | | - Eric Elguero
- MIVEGEC, Univ Montpellier, IRD, CNRS, Montpellier, France
| | - Michael J. Bangs
- Public Health & Malaria Control, International SOS, Mimika, Papua, Indonesia
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| | - Neal Alexander
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Vincent Corbel
- Univ Montpellier, Montpellier, France
- MIVEGEC, Univ Montpellier, IRD, CNRS, Montpellier, France
- * E-mail: (BF); (VC)
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Olajiga O, Holguin-Rocha AF, Rippee-Brooks M, Eppler M, Harris SL, Londono-Renteria B. Vertebrate Responses against Arthropod Salivary Proteins and Their Therapeutic Potential. Vaccines (Basel) 2021; 9:347. [PMID: 33916367 PMCID: PMC8066741 DOI: 10.3390/vaccines9040347] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/30/2021] [Accepted: 03/30/2021] [Indexed: 01/11/2023] Open
Abstract
The saliva of hematophagous arthropods contains a group of active proteins to counteract host responses against injury and to facilitate the success of a bloodmeal. These salivary proteins have significant impacts on modulating pathogen transmission, immunogenicity expression, the establishment of infection, and even disease severity. Recent studies have shown that several salivary proteins are immunogenic and antibodies against them may block infection, thereby suggesting potential vaccine candidates. Here, we discuss the most relevant salivary proteins currently studied for their therapeutic potential as vaccine candidates or to control the transmission of human vector-borne pathogens and immune responses against different arthropod salivary proteins.
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Affiliation(s)
- Olayinka Olajiga
- Vector Biology Laboratory, Department of Entomology, Kansas State University, Manhattan, KS 66506, USA; (O.O.); (A.F.H.-R.); (M.E.); (S.L.H.)
| | - Andrés F. Holguin-Rocha
- Vector Biology Laboratory, Department of Entomology, Kansas State University, Manhattan, KS 66506, USA; (O.O.); (A.F.H.-R.); (M.E.); (S.L.H.)
| | | | - Megan Eppler
- Vector Biology Laboratory, Department of Entomology, Kansas State University, Manhattan, KS 66506, USA; (O.O.); (A.F.H.-R.); (M.E.); (S.L.H.)
| | - Shanice L. Harris
- Vector Biology Laboratory, Department of Entomology, Kansas State University, Manhattan, KS 66506, USA; (O.O.); (A.F.H.-R.); (M.E.); (S.L.H.)
| | - Berlin Londono-Renteria
- Vector Biology Laboratory, Department of Entomology, Kansas State University, Manhattan, KS 66506, USA; (O.O.); (A.F.H.-R.); (M.E.); (S.L.H.)
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Fustec B, Phanitchat T, Hoq MI, Aromseree S, Pientong C, Thaewnongiew K, Ekalaksananan T, Bangs MJ, Corbel V, Alexander N, Overgaard HJ. Complex relationships between Aedes vectors, socio-economics and dengue transmission-Lessons learned from a case-control study in northeastern Thailand. PLoS Negl Trop Dis 2020; 14:e0008703. [PMID: 33001972 PMCID: PMC7553337 DOI: 10.1371/journal.pntd.0008703] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 10/13/2020] [Accepted: 08/12/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND/OBJECTIVES Dengue fever is an important public health concern in most tropical and subtropical countries, and its prevention and control rest on vector surveillance and control. However, many aspects of dengue epidemiology remain unclear; in particular, the relationship between Aedes vector abundance and dengue transmission risk. This study aims to identify entomological and immunological indices capable of discriminating between dengue case and control (non-case) houses, based on the assessment of candidate indices, as well as individual and household characteristics, as potential risk factors for acquiring dengue infection. METHODS This prospective, hospital-based, case-control study was conducted in northeastern Thailand between June 2016 and August 2019. Immature and adult stage Aedes were collected at the houses of case and control patients, recruited from district hospitals, and at patients' neighboring houses. Blood samples were tested by RDT and PCR to detect dengue cases, and were processed with the Nterm-34 kDa salivary peptide to measure the human immune response to Aedes bites. Socioeconomic status, and other individual and household characteristics were analyzed as potential risk factors for dengue. RESULTS Study findings showed complex relationships between entomological indices and dengue risk. The presence of DENV-infected Aedes at the patient house was associated with 4.2-fold higher odds of dengue. On the other hand, Aedes presence (irrespective of infectious status) in the patient's house was negatively associated with dengue. In addition, the human immune response to Aedes bites, was higher in control than in case patients and Aedes adult abundance and immature indices were higher in control than in case houses at the household and the neighboring level. Multivariable analysis showed that children aged 10-14 years old and those aged 15-25 years old had respectively 4.5-fold and 2.9-fold higher odds of dengue infection than those older than 25 years. CONCLUSION DENV infection in female Aedes at the house level was positively associated with dengue infection, while adult Aedes presence in the household was negatively associated. This study highlights the potential benefit of monitoring dengue viruses in Aedes vectors. Our findings suggest that monitoring the presence of DENV-infected Aedes mosquitoes could be a better indicator of dengue risk than the traditional immature entomological indices.
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Affiliation(s)
- Benedicte Fustec
- University of Montpellier, Montpellier, France
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Institut de Recherche pour le Developpement, Montpellier, France
| | - Thipruethai Phanitchat
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Mohammad Injamul Hoq
- School of Public Health, Epidemiology and Social Medicine at the Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Sirinart Aromseree
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Chamsai Pientong
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | | | - Tipaya Ekalaksananan
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Michael J. Bangs
- Public Health & Malaria Control, PT Freeport Indonesia/International SOS, Mimika, Papua, Indonesia
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| | - Vincent Corbel
- University of Montpellier, Montpellier, France
- Institut de Recherche pour le Developpement, Montpellier, France
| | - Neal Alexander
- MRC Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Buezo Montero S, Gabrieli P, Montarsi F, Borean A, Capelli S, De Silvestro G, Forneris F, Pombi M, Breda A, Capelli G, Arcà B. IgG Antibody Responses to the Aedes albopictus 34k2 Salivary Protein as Novel Candidate Marker of Human Exposure to the Tiger Mosquito. Front Cell Infect Microbiol 2020; 10:377. [PMID: 32850479 PMCID: PMC7405501 DOI: 10.3389/fcimb.2020.00377] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 06/18/2020] [Indexed: 01/01/2023] Open
Abstract
Mosquitoes of the Aedes genus transmit arboviruses of great importance to human health as dengue, chikungunya, Zika and yellow fever. The tiger mosquito Aedes albopictus can play an important role as arboviral vector, especially when Aedes aegypti is absent or present at low levels. Remarkably, the rapid worldwide spreading of the tiger mosquito is expanding the risk of arboviral transmission also to temperate areas, and the autochthonous cases of chikungunya, dengue and Zika in Europe emphasize the need for improved monitoring and control. Proteomic and transcriptomic studies on blood feeding arthropod salivary proteins paved the way toward the exploitation of genus-specific mosquito salivary proteins for the development of novel tools to evaluate human exposure to mosquito bites. We previously found that the culicine-specific 34k2 salivary protein from Ae. albopictus (al34k2) evokes specific IgG responses in experimentally exposed mice, and provided preliminary evidence of its immunogenicity to humans. In this study we measured IgG responses to al34k2 and to Ae. albopictus salivary gland protein extracts (SGE) in individuals naturally exposed to the tiger mosquito. Sera were collected in two areas of Northeast Italy (Padova and Belluno) during two different time periods: at the end of the low- and shortly after the high-density mosquito seasons. Anti-SGE and anti-al34k2 IgG levels increased after the summer period of exposure to mosquito bites and were higher in Padova as compared to Belluno. An age-dependent decrease of anti-saliva IgG responses was found especially in Padova, an area with at least 25 years history of Ae. albopictus colonization. Moreover, a weak correlation between anti-saliva IgG levels and individual perception of mosquito bites by study participants was found. Finally, determination of anti-al34k2 IgG1 and IgG4 levels indicated a large predominance of IgG1 antibodies. Overall, this study provides a convincing indication that antibody responses to al34k2 may be regarded as a reliable candidate marker to detect temporal and/or spatial variation of human exposure to Ae. albopictus; a serological tool of this kind may prove useful both for epidemiological studies and to estimate the effectiveness of anti-vectorial measures.
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Affiliation(s)
- Sara Buezo Montero
- Division of Parasitology, Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy
| | - Paolo Gabrieli
- Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy
| | - Fabrizio Montarsi
- Laboratory of Parasitology, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
| | - Alessio Borean
- Department of Immunohematology and Transfusion Medicine, San Martino Hospital, Belluno, Italy
| | - Stefano Capelli
- Department of Immunohematology and Transfusion Medicine, San Martino Hospital, Belluno, Italy
| | | | - Federico Forneris
- Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy
| | - Marco Pombi
- Division of Parasitology, Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy
| | - Antonio Breda
- Coordinamento Regionale Attività Trasfusionali (CRAT), Padova, Italy
| | - Gioia Capelli
- Laboratory of Parasitology, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
| | - Bruno Arcà
- Division of Parasitology, Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy
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Christofferson RC, Parker DM, Overgaard HJ, Hii J, Devine G, Wilcox BA, Nam VS, Abubakar S, Boyer S, Boonnak K, Whitehead SS, Huy R, Rithea L, Sochantha T, Wellems TE, Valenzuela JG, Manning JE. Current vector research challenges in the greater Mekong subregion for dengue, Malaria, and Other Vector-Borne Diseases: A report from a multisectoral workshop March 2019. PLoS Negl Trop Dis 2020; 14:e0008302. [PMID: 32730249 PMCID: PMC7392215 DOI: 10.1371/journal.pntd.0008302] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Affiliation(s)
- Rebecca C. Christofferson
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Daniel M. Parker
- University of California, Irvine, California, United States of America
| | | | | | - Gregor Devine
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Bruce A. Wilcox
- ASEAN Institute for Health Development, Mahidol University, Nakhon Pathom, Thailand
| | - Vu Sinh Nam
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Sazaly Abubakar
- Tropical Infectious Diseases Research and Education Center, Kuala Lumpur, Malaysia
| | | | - Kobporn Boonnak
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Stephen S. Whitehead
- National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, United States of America
| | - Rekol Huy
- National Center for Parasitology Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Leang Rithea
- National Center for Parasitology Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Tho Sochantha
- National Center for Parasitology Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Thomas E. Wellems
- National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, United States of America
| | - Jesus G. Valenzuela
- National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, United States of America
| | - Jessica E. Manning
- US National Institute of Allergy and Infectious Diseases, Phnom Penh, Cambodia
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Sagna AB, Kassié D, Couvray A, Adja AM, Hermann E, Riveau G, Salem G, Fournet F, Remoue F. Spatial Assessment of Contact Between Humans and Anopheles and Aedes Mosquitoes in a Medium-Sized African Urban Setting, Using Salivary Antibody-Based Biomarkers. J Infect Dis 2020; 220:1199-1208. [PMID: 31152664 DOI: 10.1093/infdis/jiz289] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 05/30/2019] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Anarchic and poorly controlled urbanization led to an increased risk of mosquito-borne diseases (MBD) in many African cities. Here, we evaluate the spatial heterogeneity of human exposure to malaria and arboviral disease vectors in an urban area of northern Senegal, using antibody-based biomarkers of exposure to Anopheles and Aedes mosquito bites. METHODS A cross-sectional study was undertaken during the rainy season of 2014 in 4 neighborhoods of Saint-Louis, a city in northern Senegal. Among children aged 6-59 months in each neighborhood, the dried blood spot technique was used to evaluate immunoglobulin G (IgG) responses to both gSG6-P1 (Anopheles) and Nterm-34-kDa (Aedes) salivary peptides as validated biomarkers of respective mosquito bite exposure. RESULTS IgG response levels to gSG6-P1 and Nterm-34-kDa salivary peptides varied significantly between the 4 neighborhoods (P < .0001). The level of exposure to Aedes bites also varied according to household access to sanitation services (P = .027), whereas that of exposure to Anopheles bites varied according to insecticide-treated bed net use (P = .006). In addition, spatial clusters of high contact between humans and mosquitoes were identified inside 3 neighborhoods. CONCLUSIONS Antibody-based biomarkers of exposure to Anopheles and Aedes mosquito bites could be helpful tools for evaluating the heterogeneity of exposure to malaria and arboviral disease vectors by national control programs.
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Affiliation(s)
- André B Sagna
- MIVEGEC, University of Montpellier, CNRS, IRD
- Institut Pierre Richet/Institut National de Santé Publique, Bouaké, Côte d'Ivoire
- Biomedical Research Center Espoir Pour La Santé, Saint-Louis, Sénégal
| | - Daouda Kassié
- ASTRE, University of Montpellier, CIRAD, INRA, Montpellier
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | | | - Akré Maurice Adja
- Institut Pierre Richet/Institut National de Santé Publique, Bouaké, Côte d'Ivoire
| | - Emmanuel Hermann
- CIIL, Institut Pasteur de Lille, University of Lille, CNRS UMR, Inserm, Lille, France
| | - Gilles Riveau
- CIIL, Institut Pasteur de Lille, University of Lille, CNRS UMR, Inserm, Lille, France
- Biomedical Research Center Espoir Pour La Santé, Saint-Louis, Sénégal
| | - Gérard Salem
- CEPED, University of Paris Descartes, IRD, Paris
| | - Florence Fournet
- MIVEGEC, University of Montpellier, CNRS, IRD
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
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Route of inoculation and mosquito vector exposure modulate dengue virus replication kinetics and immune responses in rhesus macaques. PLoS Negl Trop Dis 2020; 14:e0008191. [PMID: 32267846 PMCID: PMC7141610 DOI: 10.1371/journal.pntd.0008191] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 03/02/2020] [Indexed: 02/04/2023] Open
Abstract
Dengue virus (DENV) is transmitted by infectious mosquitoes during blood-feeding via saliva containing biologically-active proteins. Here, we examined the effect of varying DENV infection modality in rhesus macaques in order to improve the DENV nonhuman primate (NHP) challenge model. NHPs were exposed to DENV-1 via subcutaneous or intradermal inoculation of virus only, intradermal inoculation of virus and salivary gland extract, or infectious mosquito feeding. The infectious mosquito feeding group exhibited delayed onset of viremia, greater viral loads, and altered clinical and immune responses compared to other groups. After 15 months, NHPs in the subcutaneous and infectious mosquito feeding groups were re-exposed to either DENV-1 or DENV-2. Viral replication and neutralizing antibody following homologous challenge were suggestive of sterilizing immunity, whereas heterologous challenge resulted in productive, yet reduced, DENV-2 replication and boosted neutralizing antibody. These results show that a more transmission-relevant exposure modality resulted in viral replication closer to that observed in humans. Dengue virus is transmitted into the skin of humans by mosquitoes as they take a blood meal. In contrast, many animal models are infected in the laboratory using a syringe to inject below the skin. Here, we looked at how different routes and methods of infection altered dengue infection in rhesus macaques. We found that infection via mosquito feeding resulted in a number of changes compared to other routes and methods, including a delay in the time to detection of dengue virus and overall greater quantities of dengue virus in the blood, and changes in the amounts of various components of blood that have been associated with dengue disease in humans. After 15 months, we exposed the macaques again to either the same or a different type of dengue virus. We found that animals exposed to the same type of dengue virus were protected from infection, whereas those animals exposed to a different type were only partially protected. Overall, our results show that dengue virus delivery using the natural transmission vector, mosquitoes, results in infection that is closer to what is observed in humans and may influence the interpretation of future studies of candidate vaccines.
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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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Sri-In C, Weng SC, Chen WY, Wu-Hsieh BA, Tu WC, Shiao SH. A salivary protein of Aedes aegypti promotes dengue-2 virus replication and transmission. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 111:103181. [PMID: 31265906 DOI: 10.1016/j.ibmb.2019.103181] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/31/2019] [Accepted: 06/26/2019] [Indexed: 05/26/2023]
Abstract
Although dengue is the most prevalent arthropod-borne viral disease in humans, no effective medication or vaccine is presently available. Previous studies suggested that mosquito salivary proteins influence infection by the dengue virus (DENV) in the mammalian host. However, the effects of salivary proteins on DENV replication within the Aedes aegypti mosquito remain largely unknown. In this study, we investigated the effect of a specific salivary protein (named AaSG34) on DENV serotype 2 (DENV2) replication and transmission. We showed that transcripts of AaSG34 were upregulated in the salivary glands of Aedes aegypti mosquitoes after a meal of blood infected with DENV2. Transcripts of the dengue viral genome and envelop protein in the salivary glands were significantly diminished after an infectious blood meal when AaSG34 was silenced. The effect of AaSG34 on DENV2 transmission was investigated in Stat1-deficient mice. The intradermal inoculation of infectious mosquito saliva induced hemorrhaging in the Stat1-deficient mice; however, saliva from the AaSG34-silenced mosquitoes did not induce hemorrhaging, suggesting that AaSG34 enhances DENV2 transmission. This is the first report to demonstrate that the protein AaSG34 promotes DENV2 replication in mosquito salivary glands and enhances the transmission of the virus to the mammalian host.
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Affiliation(s)
- Chalida Sri-In
- Department of Entomology, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, Taiwan
| | - Shih-Che Weng
- Department of Tropical Medicine and Parasitology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wen-Yu Chen
- Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Betty A Wu-Hsieh
- Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wu-Chun Tu
- Department of Entomology, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, Taiwan.
| | - Shin-Hong Shiao
- Department of Tropical Medicine and Parasitology, College of Medicine, National Taiwan University, Taipei, Taiwan.
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21
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Ouédraogo S, Benmarhnia T, Bonnet E, Somé PA, Barro AS, Kafando Y, Soma DD, Dabiré RK, Saré D, Fournet F, Ridde V. Evaluation of Effectiveness of a Community-Based Intervention for Control of Dengue Virus Vector, Ouagadougou, Burkina Faso. Emerg Infect Dis 2019; 24:1859-1867. [PMID: 30226159 PMCID: PMC6154160 DOI: 10.3201/eid2410.180069] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
We evaluated the effectiveness of a community-based intervention for dengue vector control in Ouagadougou, the capital city of Burkina Faso. Households in the intervention (n = 287) and control (n = 289) neighborhoods were randomly sampled and the outcomes collected before the intervention (October 2015) and after the intervention (October 2016). The intervention reduced residents' exposure to dengue vector bites (vector saliva biomarker difference -0.08 [95% CI -0.11 to -0.04]). The pupae index declined in the intervention neighborhood (from 162.14 to 99.03) and increased in the control neighborhood (from 218.72 to 255.67). Residents in the intervention neighborhood were less likely to associate dengue with malaria (risk ratio 0.70 [95% CI 0.58-0.84]) and had increased knowledge about dengue symptoms (risk ratio 1.44 [95% CI 1.22-1.69]). Our study showed that well-planned, evidence/community-based interventions that control exposure to dengue vectors are feasible and effective in urban settings in Africa that have limited resources.
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22
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Sima M, Ferencova B, Bhattacharyya T, Miles MA, Litvinov SV, Hailu A, Baneth G, Volf P. Synthetic peptides as a novel approach for detecting antibodies against sand fly saliva. PLoS Negl Trop Dis 2019; 13:e0007078. [PMID: 30677020 PMCID: PMC6345433 DOI: 10.1371/journal.pntd.0007078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 12/13/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Hosts repeatedly bitten by sand flies develop antibodies against sand fly saliva and screening of these immunoglobulins can be employed to estimate the risk of Leishmania transmission, to indicate the feeding preferences of sand flies, or to evaluate the effectiveness of vector control campaigns. Previously, antibodies to sand fly saliva were detected using whole salivary gland homogenate (SGH) or recombinant proteins, both of which also have their disadvantages. This is the first study on sand flies where short peptides designed based on salivary antigens were successfully utilized for antibody screening. METHODOLOGY/PRINCIPAL FINDINGS Specific IgG was studied in hosts naturally exposed to Phlebotomus orientalis, the main vector of Leishmania donovani in East Africa. Four peptides were designed by the commercial program EpiQuest-B, based on the sequences of the two most promising salivary antigens, yellow-related protein and ParSP25-like protein. Short amino acid peptides were synthesised and modified for ELISA experiments. Specific anti-P. orientalis IgG was detected in sera of dogs, goats, and sheep from Ethiopia. The peptide OR24 P2 was shown to be suitable for antibody screening; it correlated positively with SGH and its specificity and sensitivity were comparable or even better than that of previously published recombinant proteins. CONCLUSIONS/SIGNIFICANCE OR24 P2, the peptide based on salivary antigen of P. orientalis, was shown to be a valuable tool for antibody screening of domestic animals naturally exposed to P. orientalis. We suggest the application of this promising methodology using species-specific short peptides to other sand fly-host combinations.
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Affiliation(s)
- Michal Sima
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Blanka Ferencova
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Tapan Bhattacharyya
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael A Miles
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Asrat Hailu
- Department of Microbiology, Immunology & Parasitology, Faculty of Medicine, Addis Ababa University, Addis Ababa, Ethiopia
| | - Gad Baneth
- School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Petr Volf
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
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Evaluation of Human Exposure to Aedes Bites in Rubber and Palm Cultivations Using an Immunoepidemiological Biomarker. BIOMED RESEARCH INTERNATIONAL 2018; 2018:3572696. [PMID: 30175128 PMCID: PMC6106716 DOI: 10.1155/2018/3572696] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 07/25/2018] [Indexed: 11/23/2022]
Abstract
Arbovirus infections, mainly transmitted by Aedes mosquito, are emerging in Africa. Efficient vector control requires an understanding of ecological factors which could impact on the risk of transmission, such as environmental changes linked to agricultural practices. The present study aims to assess the level of human exposure to Aedes mosquito bites in different agroecosystem area, using an immunological tool which quantifies human IgG antibody response to one Ae. aegypti salivary peptide. Specific IgG responses were assessed during dry and rainy seasons, in children living in different villages in Côte d'Ivoire: N'Zikro (rubber and oil palm exploitations), Ehania-V5 (oil palm), and Ayébo (without intensive agricultural activities). In the dry season, specific IgG levels were significantly lower in Ayébo compared to Ehania-V5 and N'Zikro and, interestingly, were similarly high in both villages with cultivations. In the rainy season, no difference of specific IgG was observed between villages. Specific IgG responses remained therefore high during both seasons in villages associated with intensive agricultural. The rubber and oil palm cultivations could maintain a high level of human exposure to Aedes mosquito bites during both dry and rainy seasons. These agricultural activities could represent a permanent risk factor of the transmission of arboviruses.
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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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25
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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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Overgaard HJ, Pientong C, Thaewnongiew K, Bangs MJ, Ekalaksananan T, Aromseree S, Phanitchat T, Phanthanawiboon S, Fustec B, Corbel V, Cerqueira D, Alexander N. Assessing dengue transmission risk and a vector control intervention using entomological and immunological indices in Thailand: study protocol for a cluster-randomized controlled trial. Trials 2018; 19:122. [PMID: 29458406 PMCID: PMC5819278 DOI: 10.1186/s13063-018-2490-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 01/19/2018] [Indexed: 02/07/2023] Open
Abstract
Background Dengue fever is the most common and widespread mosquito-borne arboviral disease in the world. There is a compelling need for cost-effective approaches and practical tools that can reliably measure real-time dengue transmission dynamics that enable more accurate and useful predictions of incidence and outbreaks. Sensitive surveillance tools do not exist today, and only a small handful of new control strategies are available. Vector control remains at the forefront for combating dengue transmission. However, the effectiveness of many current vector control interventions is fraught with inherent weaknesses. No single vector control method is effective enough to control both vector populations and disease transmission. Evaluations of novel larval and adult control interventions are needed. Methods/design A cluster-randomized controlled trial will be carried out between 2017 and 2019 in urban community clusters in Khon Kaen and Roi Et cities, northeastern Thailand. The effectiveness of a pyriproxyfen/spinosad combination treatment of permanent water storage containers will be evaluated on epidemiological and entomological outcomes, including dengue incidence, number of female adult dengue vectors infected or not infected with dengue virus (DENV), human exposure to Aedes mosquito bites, and several other indices. These indices will also be used to develop predictive models for dengue transmission and impending outbreaks. Epidemiological and entomological data will be collected continuously for 2 years, with the intervention implemented after 1 year. Discussion The aims of the trial are to simultaneously evaluate the efficacy of an innovative dengue vector control intervention and developing predictive dengue models. Assessment of human exposure to mosquito bites by detecting antibodies generated against Aedes saliva proteins in human blood samples has, so far, not been applied in dengue epidemiological risk assessment and disease surveillance methodologies. Likewise, DENV detection in mosquitoes (adult and immature stages) has not been used in any practical way for routine disease surveillance strategies. The integration of multiple outcome measures will assist health authorities to better predict outbreaks for planning and applying focal and timely interventions. The trial outcomes will not only be important for Thailand, but also for the entire Southeast Asian region and further afield. Trial registration ISRCTN, ISRCTN73606171. Registered on 23 June 2017. Electronic supplementary material The online version of this article (10.1186/s13063-018-2490-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Chamsai Pientong
- Khon Kaen University, Khon Kaen, Thailand.,HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | | | - Michael J Bangs
- PT Freeport Indonesia/International SOS Indonesia, Kuala Kencana, Indonesia.,Kasetsart University, Bangkok, Thailand
| | - Tipaya Ekalaksananan
- Khon Kaen University, Khon Kaen, Thailand.,HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Sirinart Aromseree
- Khon Kaen University, Khon Kaen, Thailand.,HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | | | - Supranee Phanthanawiboon
- Khon Kaen University, Khon Kaen, Thailand.,HPV & EBV and Carcinogenesis Research Group, Khon Kaen University, Khon Kaen, Thailand
| | - Benedicte Fustec
- Khon Kaen University, Khon Kaen, Thailand.,Université de Montpellier, Montpellier, France
| | - Vincent Corbel
- Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC, UM1-CNRS 5290-IRD 224), Montpellier, France
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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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Somda MB, Cornelie S, Bengaly Z, Mathieu-Daudé F, Poinsignon A, Dama E, Bouyer J, Sidibé I, Demettre E, Seveno M, Remoué F, Sanon A, Bucheton B. Identification of a Tsal152-75 salivary synthetic peptide to monitor cattle exposure to tsetse flies. Parasit Vectors 2016; 9:149. [PMID: 26979518 PMCID: PMC4791801 DOI: 10.1186/s13071-016-1414-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 03/01/2016] [Indexed: 01/10/2023] Open
Abstract
Background The saliva of tsetse flies contains a cocktail of bioactive molecules inducing specific antibody responses in hosts exposed to bites. We have previously shown that an indirect-ELISA test using whole salivary extracts from Glossina morsitans submorsitans was able to discriminate between (i) cattle from tsetse infested and tsetse free areas and (ii) animals experimentally exposed to low or high numbers of tsetse flies. In the present study, our aim was to identify specific salivary synthetic peptides that could be used to develop simple immunoassays to measure cattle exposure to tsetse flies. Methods In a first step, 2D-electrophoresis immunoblotting, using sera from animals exposed to a variety of bloodsucking arthropods, was performed to identify specific salivary proteins recognised in cattle exposed to tsetse bites. Linear epitope prediction software and Blast analysis were then used to design synthetic peptides within the identified salivary proteins. Finally, candidate peptides were tested by indirect-ELISA on serum samples from tsetse infested and tsetse free areas, and from exposure experiments. Results The combined immunoblotting and bioinformatics analyses led to the identification of five peptides carrying putative linear epitopes within two salivary proteins: the tsetse salivary gland protein 1 (Tsal1) and the Salivary Secreted Adenosine (SSA). Of these, two were synthesised and tested further based on the absence of sequence homology with other arthropods or pathogen species. IgG responses to the Tsal152–75 synthetic peptide were shown to be specific of tsetse exposure in both naturally and experimentally exposed hosts. Nevertheless, anti-Tsal152–75 IgG responses were absent in animals exposed to high tsetse biting rates. Conclusions These results suggest that Tsal152–75 specific antibodies represent a biomarker of low cattle exposure to tsetse fly. These results are discussed in the light of the other available tsetse saliva based-immunoassays and in the perspective of developing a simple serological tool for tsetse eradication campaigns to assess the tsetse free status or to detect tsetse reemergence in previously cleared areas. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1414-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Martin Bienvenu Somda
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 01 BP 454, Bobo-Dioulasso 01, Burkina Faso. .,Université Polytechnique de Bobo-Dioulasso, 01 BP 1 091, Bobo-Dioulasso 01, Burkina Faso.
| | - Sylvie Cornelie
- Institut de Recherche pour le Développement (IRD), Unité Mixte de Recherche 224, Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, 34394 Cedex 5, France
| | - Zakaria Bengaly
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 01 BP 454, Bobo-Dioulasso 01, Burkina Faso
| | - Françoise Mathieu-Daudé
- Institut de Recherche pour le Développement (IRD), Unité Mixte de Recherche 224, Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, 34394 Cedex 5, France
| | - Anne Poinsignon
- Institut de Recherche pour le Développement (IRD), Unité Mixte de Recherche 224, Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, 34394 Cedex 5, France
| | - Emilie Dama
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 01 BP 454, Bobo-Dioulasso 01, Burkina Faso.,Université Polytechnique de Bobo-Dioulasso, 01 BP 1 091, Bobo-Dioulasso 01, Burkina Faso
| | - Jeremy Bouyer
- CIRAD, UMR CIRAD-INRA Contrôle des Maladies Animales, Campus International de Baillarguet, F34398, Montpellier, France.,Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Interactions hôtes-vecteurs-parasites dans les maladies dues aux Trypanosomatidae, Campus International de Baillarguet, Montpellier, 34398 Cedex 5, France
| | - Issa Sidibé
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 01 BP 454, Bobo-Dioulasso 01, Burkina Faso.,Pan African Tsetse and Trypanosomosis Eradication Campaign (PATTEC), Projet de Création de Zones Libérées Durablement de Tsé-tsé et de Trypanosomoses (PCZLD), Bobo-Dioulasso, Burkina Faso
| | - Edith Demettre
- Institut de Génomique Fonctionnelle, CNRS UMR 5203, INSERM U1191, UM1, UM2, Plate-forme de Protéomique Fonctionnelle CNRS UMS BioCampus 3426, 34094, Montpellier, France
| | - Martial Seveno
- Institut de Génomique Fonctionnelle, CNRS UMR 5203, INSERM U1191, UM1, UM2, Plate-forme de Protéomique Fonctionnelle CNRS UMS BioCampus 3426, 34094, Montpellier, France
| | - Franck Remoué
- Institut de Recherche pour le Développement (IRD), Unité Mixte de Recherche 224, Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Montpellier, 34394 Cedex 5, France
| | - Antoine Sanon
- Université de Ouagadougou, UFR/SVT, Laboratoire d'Entomologie Fondamentale et Appliquée (LEFA), BP 9499, Ouagadougou 06, Burkina Faso
| | - Bruno Bucheton
- Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Interactions hôtes-vecteurs-parasites dans les maladies dues aux Trypanosomatidae, Campus International de Baillarguet, Montpellier, 34398 Cedex 5, France
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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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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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Ndille EE, Dubot-Pérès A, Doucoure S, Mouchet F, Cornelie S, Sidavong B, Fournet F, Remoue F. Human IgG antibody response to Aedes aegypti Nterm-34 kDa salivary peptide as an indicator to identify areas at high risk for dengue transmission: a retrospective study in urban settings of Vientiane city, Lao PDR. Trop Med Int Health 2014; 19:576-80. [PMID: 24641205 DOI: 10.1111/tmi.12280] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE Using human IgG antibody response to the Aedes Nterm-34 kDa salivary peptide as an indicator of human exposure to Aedes bites in surveying exposed populations from areas at risk of dengue virus (DENV) transmission in urban settings of Vientiane city, Lao PDR. METHODS Enzyme-linked immunosorbent assay tests were performed to measure the IgG response to Nterm-34 kDa peptide in blood samples collected within a flavivirus seroprevalence survey carried out in 2006 including 3558 randomly selected individuals. The level of IgG response to the Nterm-34 kDa peptide in individuals was analysed in relation to the level of urbanisation of the individual's residence, areas that presented significant differences in the prevalence of recent DENV infection. RESULTS No differences were observed in the anti-Nterm-34 kDa IgG level between DENV-positive and DENV-negative individuals. However, the level of specific IgG response was higher among individuals living in slightly urbanised neighbourhoods than among those in more highly urbanised areas (P < 0.0001). Interestingly, a similar pattern had already been observed concerning the prevalence of recent DENV infection in the same populations. CONCLUSION The results of this retrospective study indicate that the evaluation of human IgG response to the Aedes Nterm-34 kDa salivary peptide could be a useful indicator to identify places with risk of dengue virus transmission in urban endemic areas.
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Affiliation(s)
- Emmanuel Elanga Ndille
- Institut de recherche pour le développement (IRD), UMR Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle, UMR IRD 224 - CNRS 5290 - Universities of Montpellier 1 and 2, Cotonou, Bénin; Centre de Recherche Entomologique de Cotonou, Ministère de la Santé Publique, Cotonou, Bénin
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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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Dama E, Cornelie S, Camara M, Somda MB, Poinsignon A, Ilboudo H, Elanga Ndille E, Jamonneau V, Solano P, Remoue F, Bengaly Z, Belem AMG, Bucheton B. In silico identification of a candidate synthetic peptide (Tsgf118-43) to monitor human exposure to tsetse flies in West Africa. PLoS Negl Trop Dis 2013; 7:e2455. [PMID: 24086785 PMCID: PMC3784472 DOI: 10.1371/journal.pntd.0002455] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 08/12/2013] [Indexed: 01/31/2023] Open
Abstract
Background The analysis of humoral responses directed against the saliva of blood-sucking arthropods was shown to provide epidemiological biomarkers of human exposure to vector-borne diseases. However, the use of whole saliva as antigen presents several limitations such as problems of mass production, reproducibility and specificity. The aim of this study was to design a specific biomarker of exposure to tsetse flies based on the in silico analysis of three Glossina salivary proteins (Ada, Ag5 and Tsgf1) previously shown to be specifically recognized by plasma from exposed individuals. Methodology/Principal Findings Synthetic peptides were designed by combining several linear epitope prediction methods and Blast analysis. The most specific peptides were then tested by indirect ELISA on a bank of 160 plasma samples from tsetse infested areas and tsetse free areas. Anti-Tsgf118–43 specific IgG levels were low in all three control populations (from rural Africa, urban Africa and Europe) and were significantly higher (p<0.0001) in the two populations exposed to tsetse flies (Guinean HAT foci, and South West Burkina Faso). A positive correlation was also found between Anti-Tsgf118–43 IgG levels and the risk of being infected by Trypanosoma brucei gambiense in the sleeping sickness foci of Guinea. Conclusion/Significance The Tsgf118–43 peptide is a suitable and promising candidate to develop a standardize immunoassay allowing large scale monitoring of human exposure to tsetse flies in West Africa. This could provide a new surveillance indicator for tsetse control interventions by HAT control programs. Increasing interest is paid to blood-sucking arthropod's salivary antigens to develop host direct biomarkers of exposure. Nevertheless use of whole saliva is problematic both because of mass production and specificity issues. Here, we describe an in silico approach we used to identify potential epitopes on the amino acid sequence of three tsetse salivary proteins (Ada, Ag5 and Tsgf1) that were previously shown to be specifically recognized by antibodies from exposed individuals. Three candidate peptides were synthesized and evaluated on a set of plasma collected in different tsetse-infested and tsetse-free areas. The Tsgf118–43 synthetic peptide appeared as a promising candidate to assess human exposure to tsetse flies as antibody responses were low in all three control groups and were significantly higher in our two exposed groups. Significantly higher anti- Tsgf118–43 responses were also observed in sleeping sickness patients as compared to uninfected controls suggesting that Tsgf118–43 may be used both to assess human tsetse contacts and the risk of infection by trypanosomes. This new sero-epidemiological tool could thus help National Control Programs to quickly map human exposure levels in order to better target vector control efforts and monitor vector control efficiency.
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Affiliation(s)
- Emilie Dama
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
| | - Sylvie Cornelie
- Institut de Recherche pour le Développement (IRD), UMR MIVEGEC IRD 224-CNRS 5290-Université de Montpellier 1 et Montpellier 2, Montpellier, France
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Mamadou Camara
- Programme National de Lutte contre la Trypanosomose Humaine Africaine en Guinée, Conakry, Guinée
| | - Martin Bienvenu Somda
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
| | - Anne Poinsignon
- Institut de Recherche pour le Développement (IRD), UMR MIVEGEC IRD 224-CNRS 5290-Université de Montpellier 1 et Montpellier 2, Montpellier, France
| | - Hamidou Ilboudo
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
| | - Emmanuel Elanga Ndille
- Institut de Recherche pour le Développement (IRD), UMR MIVEGEC IRD 224-CNRS 5290-Université de Montpellier 1 et Montpellier 2, Montpellier, France
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Vincent Jamonneau
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
- Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Campus International de Baillarguet, Montpellier, France
| | - Philippe Solano
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
- Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Campus International de Baillarguet, Montpellier, France
| | - Franck Remoue
- Institut de Recherche pour le Développement (IRD), UMR MIVEGEC IRD 224-CNRS 5290-Université de Montpellier 1 et Montpellier 2, Montpellier, France
- Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin
| | - Zakaria Bengaly
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
| | | | - Bruno Bucheton
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
- Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Campus International de Baillarguet, Montpellier, France
- * E-mail:
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Aedes aegypti saliva contains a prominent 34-kDa protein that strongly enhances dengue virus replication in human keratinocytes. J Invest Dermatol 2013; 134:281-284. [PMID: 23752041 DOI: 10.1038/jid.2013.251] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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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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Dama E, Cornelie S, Bienvenu Somda M, Camara M, Kambire R, Courtin F, Jamonneau V, Demettre E, Seveno M, Bengaly Z, Solano P, Poinsignon A, Remoue F, Belem AMG, Bucheton B. Identification of Glossina palpalis gambiensis specific salivary antigens: towards the development of a serologic biomarker of human exposure to tsetse flies in West Africa. Microbes Infect 2013; 15:416-27. [PMID: 23500186 DOI: 10.1016/j.micinf.2013.03.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 02/26/2013] [Accepted: 03/01/2013] [Indexed: 12/27/2022]
Abstract
The saliva of blood sucking arthropods contains a number of pharmacologically active compounds that induce an antibody response in exposed human individuals. The objectives of the present study were (i) to assess the human IgG response directed against salivary antigens of Glossina palpalis gambiensis, the main vector of Trypanosoma brucei gambiense in West Africa, as a biomarker of human-tsetse contacts; and (ii) to identify specific salivary antigens. Immune reactivity of human plasma collected within active human African trypanosomiasis (HAT) foci (coastal Guinea), historical foci where tsetse flies are still present (South-West Burkina Faso) and a tsetse free area (Bobo-Dioulasso, Burkina Faso), was measured by ELISA against whole saliva extracts. In the active HAT foci and areas where tsetse flies were present in high densities, specific IgG responses were significantly higher (p < 0.0001) to those in Bobo-Dioulasso or in Loropeni, where tsetse flies were either absent or only present at low densities. Furthermore, 2D-electrophoresis combined with mass spectrometry enabled to reveal that several antigens were specifically recognized by plasma from exposed individuals. Among them, four salivary proteins were successfully identified (Ada, 5'Nuc, Ag5 and Tsgf1). These results represent a first attempt to identify Glossina salivary proteins or synthetic peptides to develop a standardized and specific biomarker of tsetse exposure in West Africa.
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Affiliation(s)
- Emilie Dama
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide CIRDES, 01 BP 454 Bobo-Dioulasso 01, Burkina Faso
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