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Poungou N, Sevidzem SL, Koumba AA, Koumba CRZ, Mbehang P, Onanga R, Zahouli JZB, Maganga GD, Djogbénou LS, Borrmann S, Adegnika AA, Becker SC, Mavoungou JF, Nguéma RM. Mosquito-Borne Arboviruses Occurrence and Distribution in the Last Three Decades in Central Africa: A Systematic Literature Review. Microorganisms 2023; 12:4. [PMID: 38276174 PMCID: PMC10819313 DOI: 10.3390/microorganisms12010004] [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: 09/19/2023] [Revised: 10/13/2023] [Accepted: 10/19/2023] [Indexed: 01/27/2024] Open
Abstract
Arboviruses represent a real public health problem globally and in the Central African subregion in particular, which represents a high-risk zone for the emergence and re-emergence of arbovirus outbreaks. Furthermore, an updated review on the current arbovirus burden and associated mosquito vectors is lacking for this region. To contribute to filling this knowledge gap, the current study was designed with the following objectives: (i) to systematically review data on the occurrence and distribution of arboviruses and mosquito fauna; and (ii) to identify potential spillover mosquito species in the Central African region in the last 30 years. A web search enabled the documentation of 2454 articles from different online databases. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) and the quality of reporting of meta-analyses (QUORUM) steps for a systematic review enabled the selection of 164 articles that fulfilled our selection criteria. Of the six arboviruses (dengue virus (DENV), chikungunya virus (CHIKV), yellow fever virus (YFV), Zika virus (ZIKV), Rift Valley fever virus (RVFV), and West Nile virus (WNV)) of public health concern studied, the most frequently reported were chikungunya and dengue. The entomological records showed >248 species of mosquitoes regrouped under 15 genera, with Anopheles (n = 100 species), Culex (n = 56 species), and Aedes (n = 52 species) having high species diversity. Three genera were rarely represented, with only one species included, namely, Orthopodomyia, Lutzia, and Verrallina, but individuals of the genera Toxorhinchites and Finlayas were not identified at the species level. We found that two Aedes species (Ae. aegypti and Ae. albopictus) colonised the same microhabitat and were involved in major epidemics of the six medically important arboviruses, and other less-frequently identified mosquito genera consisted of competent species and were associated with outbreaks of medical and zoonotic arboviruses. The present study reveals a high species richness of competent mosquito vectors that could lead to the spillover of medically important arboviruses in the region. Although epidemiological studies were found, they were not regularly documented, and this also applies to vector competence and transmission studies. Future studies will consider unpublished information in dissertations and technical reports from different countries to allow their information to be more consistent. A regional project, entitled "Ecology of Arboviruses" (EcoVir), is underway in three countries (Gabon, Benin, and Cote d'Ivoire) to generate a more comprehensive epidemiological and entomological data on this topic.
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Affiliation(s)
- Natacha Poungou
- Ecole Doctorale Regionale en Infectiologie Tropical de Franceville (EDR), University of Science and Technique of Masuku (USTM), Franceville P.O. Box 943, Gabon;
- Laboratoire d’Ecologie des Maladies Transmissibles (LEMAT), Université Libreville Nord (ULN), Libreville P.O. Box 1177, Gabon
| | - Silas Lendzele Sevidzem
- Laboratoire d’Ecologie des Maladies Transmissibles (LEMAT), Université Libreville Nord (ULN), Libreville P.O. Box 1177, Gabon
| | - Aubin Armel Koumba
- Département de Biologie et Ecologie Animale, Institut de Recherche en Ecologie Tropicale (IRET-CENAREST), Libreville P.O. Box 13354, Gabon
| | - Christophe Roland Zinga Koumba
- Département de Biologie et Ecologie Animale, Institut de Recherche en Ecologie Tropicale (IRET-CENAREST), Libreville P.O. Box 13354, Gabon
| | - Phillipe Mbehang
- Département de Biologie et Ecologie Animale, Institut de Recherche en Ecologie Tropicale (IRET-CENAREST), Libreville P.O. Box 13354, Gabon
| | - Richard Onanga
- Center of Interdisciplinary Medical Analysis of Franceville (CIRMF), Franceville P.O. Box 769, Gabon
| | - Julien Zahouli Bi Zahouli
- Centre d’Entomologie Médicale et Vétérinaire, Université Alassane Ouattara, Bouaké 01 BPV 18, Côte d’Ivoire
| | - Gael Darren Maganga
- Center of Interdisciplinary Medical Analysis of Franceville (CIRMF), Franceville P.O. Box 769, Gabon
| | - Luc Salako Djogbénou
- Université d’Abomey-Calavi, Institut Régional de Santé Publique, Ouidah P.O. Box 384, Benin
| | - Steffen Borrmann
- Institute for Tropical Medicine (ITM), University of Tübingen, 72074 Tübingen, Germany
| | - Ayola Akim Adegnika
- Centre de Recherches Médicales de Lambaréné (CERMEL), Lambaréné P.O. Box 242, Gabon
| | - Stefanie C. Becker
- Institute for Parasitology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany;
| | - Jacques François Mavoungou
- Département de Biologie et Ecologie Animale, Institut de Recherche en Ecologie Tropicale (IRET-CENAREST), Libreville P.O. Box 13354, Gabon
| | - Rodrigue Mintsa Nguéma
- Laboratoire d’Ecologie des Maladies Transmissibles (LEMAT), Université Libreville Nord (ULN), Libreville P.O. Box 1177, Gabon
- Département de Biologie et Ecologie Animale, Institut de Recherche en Ecologie Tropicale (IRET-CENAREST), Libreville P.O. Box 13354, Gabon
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Akyea-Bobi NE, Akorli J, Opoku M, Akporh SS, Amlalo GK, Osei JHN, Frempong KK, Pi-Bansa S, Boakye HA, Abudu M, Akorli EA, Acquah-Baidoo D, Pwalia R, Bonney JHK, Quansah R, Dadzie SK. Entomological risk assessment for transmission of arboviral diseases by Aedes mosquitoes in a domestic and forest site in Accra, Ghana. PLoS One 2023; 18:e0295390. [PMID: 38060554 PMCID: PMC10703219 DOI: 10.1371/journal.pone.0295390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 11/20/2023] [Indexed: 12/18/2023] Open
Abstract
Dengue, Zika and chikungunya are Aedes-borne viral diseases that have become great global health concerns in the past years. Several countries in Africa have reported outbreaks of these diseases and despite Ghana sharing borders with some of these countries, such outbreaks are yet to be detected. Viral RNA and antibodies against dengue serotype-2 have recently been reported among individuals in some localities in the regional capital of Ghana. This is an indication of a possible silent transmission ongoing in the population. This study, therefore, investigated the entomological transmission risk of dengue, Zika and chikungunya viruses in a forest and domestic population in the Greater Accra Region, Ghana. All stages of the Aedes mosquito (egg, larvae, pupae and adults) were collected around homes and in the forest area for estimation of risk indices. All eggs were hatched and reared to larvae or adults for morphological identification together with larvae and adults collected from the field. The forest population had higher species richness with 7 Aedes species. The predominant species of Aedes mosquitoes identified from both sites was Aedes aegypti (98%). Aedes albopictus, an important arbovirus vector, was identified only in the peri-domestic population at a prevalence of 1.5%, significantly higher than previously reported. All risk indices were above the WHO threshold except the House Index for the domestic site which was moderate (19.8). The forest population recorded higher Positive Ovitrap (34.2% vs 26.6%) and Container (67.9% vs 36.8%) Indices than the peri-domestic population. Although none of the mosquito pools showed the presence of dengue, chikungunya or Zika viruses, all entomological risk indicators showed that both sites had a high potential arboviral disease transmission risk should any of these viruses be introduced. Continuous surveillance is recommended in these and other sites in the Metropolis to properly map transmission risk areas to inform outbreak preparedness strategies.
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Affiliation(s)
- Nukunu Etornam Akyea-Bobi
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Jewelna Akorli
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Millicent Opoku
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Samuel Sowah Akporh
- Vestergaard NMIMR Vector Labs, Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Godwin Kwame Amlalo
- Vestergaard NMIMR Vector Labs, Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Joseph Harold Nyarko Osei
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Kwadwo Kyereme Frempong
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Sellase Pi-Bansa
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Helena Anokyewaa Boakye
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Mufeez Abudu
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Esinam Abla Akorli
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Dominic Acquah-Baidoo
- Vestergaard NMIMR Vector Labs, Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | - Rebecca Pwalia
- Vestergaard NMIMR Vector Labs, Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
| | | | - Reginald Quansah
- Department of Biological, Environmental and Occupational Health, School of Public Health, University of Ghana, Legon, Accra
| | - Samuel Kweku Dadzie
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Accra
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Agbodzi B, Sado Yousseu FB, Nemg Simo FB, Kumordjie S, Yeboah C, Mosore MT, Bentil RE, Coatsworth HG, Attram N, Nimo-Paintsil S, Fox AT, Bonney JHK, Ampofo W, Dinglasan RR, Sanders T, Wiley MR, Demanou M, Letizia AG. Whole genome sequencing of outbreak strains from 2017 to 2018 reveals an endemic clade of dengue 1 virus in Cameroon. Emerg Microbes Infect 2023; 12:2281352. [PMID: 37933502 PMCID: PMC10732222 DOI: 10.1080/22221751.2023.2281352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Accepted: 11/04/2023] [Indexed: 11/08/2023]
Abstract
Dengue fever is expanding as a global public health threat including countries within Africa. For the past few decades, Cameroon has experienced sporadic cases of arboviral infections including dengue fever. Here, we conducted genomic analyses to investigate the origin and phylogenetic profile of Cameroon DENV-1 outbreak strains and predict the impact of emerging therapeutics on these strains. Bayesian and maximum-likelihood phylogenetic inference approaches were employed in virus evolutionary analyses. An in silico analysis was performed to assess the divergence in immunotherapeutic and vaccine targets in the new genomes. Six complete DENV-1 genomes were generated from 50 samples that met a clinical definition for DENV infection. Phylogenetic analyses revealed that the strains from the current study belong to a sub-lineage of DENV-1 genotype V and form a monophyletic taxon with a 2012 strain from Gabon. The most recent common ancestor (TMRCA) of the Cameroon and Gabon strains was estimated to have existed around 2008. Comparing our sequences to the vaccine strains, 19 and 15 amino acid (aa) substitutions were observed in the immuno-protective prM-E protein segments of the Dengvaxia® and TetraVax-DV-TV003 vaccines, respectively. Epitope mapping revealed mismatches in aa residues at positions E155 and E161 located in the epitope of the human anti-DENV-1 monoclonal antibody HMAb 1F4. The new DENV strains constitute a conserved genomic pool of viruses endemic to the Central African region that needs prospective monitoring to track local viral evolution. Further work is needed to ascertain the performance of emerging therapeutics in DENV strains from the African region.
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Affiliation(s)
- Bright Agbodzi
- U.S. Naval Medical Research Unit EURAFCENT, Accra, Ghana
| | | | | | | | - Clara Yeboah
- U.S. Naval Medical Research Unit EURAFCENT, Accra, Ghana
| | | | | | - Heather G. Coatsworth
- Department of Infectious Diseases & Immunology and Emerging Pathogens Institute, College of Veterinary Medicine, University of Florida, Gainesville, Florida, USA
| | - Naiki Attram
- U.S. Naval Medical Research Unit EURAFCENT, Accra, Ghana
| | | | - Anne T. Fox
- U.S. Naval Medical Research Unit EURAFCENT, Accra, Ghana
| | - Joseph H. K. Bonney
- Virology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - William Ampofo
- Virology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Rhoel R. Dinglasan
- Department of Infectious Diseases & Immunology and Emerging Pathogens Institute, College of Veterinary Medicine, University of Florida, Gainesville, Florida, USA
| | - Terrel Sanders
- U.S. Naval Medical Research Unit EURAFCENT, Accra, Ghana
| | - Michael R. Wiley
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
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Canelas T, Thomsen E, Kamgang B, Kelly‐Hope LA. Demographic and environmental factors associated with the distribution of Aedes albopictus in Cameroon. MEDICAL AND VETERINARY ENTOMOLOGY 2023; 37:143-151. [PMID: 36264191 PMCID: PMC10092813 DOI: 10.1111/mve.12619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 09/26/2022] [Indexed: 06/16/2023]
Abstract
Aedes-transmitted arboviruses have spread globally due to the spread of Aedes aegypti and Aedes albopictus. Its distribution is associated with human and physical geography. However, these factors have not been quantified in Cameroon. Therefore, the aim was to develop an Ae. albopictus geo-referenced database to examine the risk factors associated with the vector distribution in Cameroon. Data on the Ae. albopictus presence and absence were collated and mapped from studies in published scientific literature between 2000 and 2020. Publicly available earth observation data were used to assess human geography, land use and climate risk factors related to the vector distribution. A logistic binomial regression was conducted to identify the significant risk factors associated with Ae. albopictus distribution. In total, 111 data points were collated (presence = 87; absence = 24). Different data collection methods and sites hindered the spatiotemporal analysis. An increase of one wet month in a year increased the odds of Ae. albopictus presence by 5.6 times. One unit of peri-urban area increased the odds by 1.3 times. Using publicly available demographic and environmental data to better understand the key determinants of mosquito distributions may facilitate appropriately targeted public health messages and vector control strategies.
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Affiliation(s)
- Tiago Canelas
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
- Medical Research Council Epidemiology UnitUniversity of CambridgeCambridgeUK
| | - Edward Thomsen
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Basile Kamgang
- Department of Medical EntomologyCentre for Research in Infectious DiseasesYaoundéCameroon
| | - Louise A. Kelly‐Hope
- Department of Livestock and One HealthInstitute of Infection, Veterinary and Ecological Sciences, University of LiverpoolLiverpoolUK
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Agha SB, Tchouassi DP. Urbanization of Aedes mosquito populations and evolution of arboviral disease risk in Africa. CURRENT OPINION IN INSECT SCIENCE 2022; 54:100988. [PMID: 36332839 DOI: 10.1016/j.cois.2022.100988] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 10/20/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
The arboviral diseases dengue, chikungunya, and yellow fever are re-merging and gaining a foothold in Africa, with a significant threat of large outbreaks in urban areas. Although their emergence is intimately linked to the primary vector Aedes aegypti, which thrives in urban environments, the risk of these diseases remains substantially heterogeneous in different geographic areas. Range expansion of invasive mosquito species Aedes albopictus, and colonization of urban habitats by sylvatic and peridomestic Aedes vectors, are likely to alter the diseases' epidemiology. We discuss how a network of different vector species and perhaps vector subpopulations could interact with associated serotypes/genotypes/lineages of the causative viruses of these diseases potentially impacting transmission risk in urban landscapes with implications for disease surveillance and control.
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Affiliation(s)
- Sheila B Agha
- International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya.
| | - David P Tchouassi
- International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya
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MALDI-TOF MS: An effective tool for a global surveillance of dengue vector species. PLoS One 2022; 17:e0276488. [PMID: 36264911 PMCID: PMC9584457 DOI: 10.1371/journal.pone.0276488] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 10/07/2022] [Indexed: 11/20/2022] Open
Abstract
Dengue, Zika and chikungunya viruses cause significant human public health burdens in the world. These arboviruses are transmitted by vector mosquito species notably Aedes aegypti and Aedes albopictus. In the Pacific region, more vector species of arboviruses belonging to the Scutellaris Group are present. Due to the expansion of human travel and international trade, the threat of their dispersal in other world regions is on the rise. Strengthening of entomological surveillance ensuring rapid detection of introduced vector species is therefore required in order to avoid their establishment and the risk of arbovirus outbreaks. This surveillance relies on accurate species identification. The aim of this study was to assess the use of the Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) as a tool for an international identification and surveillance of these mosquito vectors of arboviruses. Field-mosquitoes belonging to 8 species (Ae. aegypti, Ae. albopictus, Aedes polynesiensis, Aedes scutellaris, Aedes pseudoscutellaris, Aedes malayensis, Aedes futunae and Culex quinquefasciatus) from 6 countries in the Pacific, Asian and Madagascar, were included in this study. Analysis provided evidence that a MALDI-TOF database created using mosquitoes from the Pacific region allowed suitable identification of mosquito species from the other regions. This technic was as efficient as the DNA sequencing method in identifying mosquito species. Indeed, with the exception of two Ae. pseudoscutellaris, an exact species identification was obtained for all individual mosquitoes. These findings highlight that the MALDI-TOF MS is a promising tool that could be used for a global comprehensive arbovirus vector surveillance.
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Ali IM, Tchuenkam VPK, Colton M, Stittleburg V, Mitchell C, Gaither C, Thwai K, Espinoza DO, Zhu Y, Jamal H, Key A, Juliano JJ, Christopher TB, Piantadosi A, Waggoner JJ, Collins MH. Arboviruses as an unappreciated cause of non-malarial acute febrile illness in the Dschang Health District of western Cameroon. PLoS Negl Trop Dis 2022; 16:e0010790. [PMID: 36223421 PMCID: PMC9591055 DOI: 10.1371/journal.pntd.0010790] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 10/24/2022] [Accepted: 09/05/2022] [Indexed: 11/07/2022] Open
Abstract
Acute febrile illness is a common problem managed by clinicians and health systems globally, particularly in the Tropics. In many regions, malaria is a leading and potentially deadly cause of fever; however, myriad alternative etiologies exist. Identifying the cause of fever allows optimal management, but this depends on many factors including thorough knowledge of circulating infections. Arboviruses such as dengue (DENV) cause fever and may be underdiagnosed in sub-Saharan Africa where malaria is a major focus. We examined cases of fever in western Cameroon that tested negative for malaria and found 13.5% (13/96) were due to DENV, with 75% (9/12) of these being DENV serotype 2 infections. Two complete DENV2 genomes were obtained and clustered closely to recent isolates from Senegal and Burkina Faso. The seroprevalence of DENV in this region was 24.8% (96/387). Neutralizing antibodies to DENV2 were detected in all (15/15) seropositive samples tested. Chikungunya (CHIKV) is an arthritogenic alphavirus that is transmitted by Aedes mosquitoes, the same principal vector as DENV. The seroprevalence for CHIKV was 15.7% (67/427); however, CHIKV did not cause a single case of fever in the 96 subjects tested. Of note, being seropositive for one arbovirus was associated with being seropositive for the other (Χ2 = 16.8, p<0.001). Taken together, these data indicate that Aedes-transmitted arboviruses are endemic in western Cameroon and are likely a common but underappreciated cause of febrile illness. This work supports the need for additional study of arboviruses in sub-Saharan Africa and efforts to improve diagnostic capacity, surveillance systems, and arbovirus prevention strategies. Acute illness with fever is common but can be challenging for clinicians to manage, particularly in resource-limited settings. In sub-Saharan Africa, malaria is a major cause of fever, but other causes of fever are poorly documented or monitored, which impairs optimal medical care to patients and implementation of public health interventions to control leading causes of disease. Viruses transmitted by mosquitoes are a prevalent and expanding problem throughout the tropics and beyond; however, there is concern that these infections frequently go undetected in sub-Saharan Africa. We discovered a previously unrecognized outbreak of dengue virus in western Cameroon by testing remnant samples from over 400 patients that presented with fever. Our results indicate that dengue has circulated in this region for decades with little recognition. This study adds important information about causes of fever in sub-Saharan Africa and advocates for increasing investment in surveillance systems and prevention strategies for mosquito-borne viruses.
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Affiliation(s)
- Innocent M. Ali
- Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, West Region of Cameroon, Cameroon
| | - Valery P. K. Tchuenkam
- Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, West Region of Cameroon, Cameroon
| | - Mia Colton
- Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Victoria Stittleburg
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Cedar Mitchell
- Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Claudia Gaither
- Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Kyaw Thwai
- Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Daniel O. Espinoza
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Yerun Zhu
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Haaris Jamal
- Emory University, Atlanta, Georgia, United States of America
| | - Autum Key
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Jonathan J. Juliano
- Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Tume B. Christopher
- Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, West Region of Cameroon, Cameroon
| | - Anne Piantadosi
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Jesse J. Waggoner
- Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Matthew H. Collins
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail:
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Nana-Ndjangwo SM, Djiappi-Tchamen B, Mony R, Demanou M, Keumezeu-Tsafack J, Bamou R, Awono-Ambene P, Bilong Bilong CF, Antonio-Nkondjio C. Assessment of Dengue and Chikungunya Infections among Febrile Patients Visiting Four Healthcare Centres in Yaoundé and Dizangué, Cameroon. Viruses 2022; 14:v14102127. [PMID: 36298682 PMCID: PMC9612120 DOI: 10.3390/v14102127] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/09/2022] [Accepted: 09/17/2022] [Indexed: 11/16/2022] Open
Abstract
Dengue and chikungunya are now widely distributed in Cameroon, but there is still not enough information on their prevalence in different epidemiological settings. This study was undertaken to assess the prevalence of dengue and chikungunya in both urban and rural settings in Cameroon using three diagnostic tools. From December 2019 to September 2021, willing febrile (temperature >38 °C) outpatients visiting four healthcare facilities in the cities of Yaoundé and Dizangué were screened for dengue, and chikungunya. Clinical features of patient were recorded in a form, and their blood samples were analysed using real-time reverse transcriptase-polymerase chain reaction (rtRT-PCR), rapid diagnostic tests (RDTs) and enzyme-linked immuno-sorbent assays (ELISA). Odds ratios were used to determine the level of association between socio-demographic factors, clinical features, and infection status. The Kappa coefficient permitted to assess the level of agreement between RDTs and ELISA. Overall, 301 febrile patients were recruited in the study: 198 in Yaoundé and 103 in Dizangué. The prevalence of infection varied with the diagnostic tool used. For dengue diagnostics, 110 patients were positive to rtRT-PCR: 90 (45.45%) in Yaoundé, and 20 (19.42%) in Dizangué. The prevalence of dengue IgM using ELISA varied from 22.3% in Dizangué to 30.8% in Yaoundé. Dengue IgM rate using RDTs was 7.6% in Yaoundé and 3.9% in Dizangué. For chikungunya, one (0.5%) patient (Yaoundé, suburb) was positive to rtRT-PCR. The prevalence of chikungunya IgM according to ELISA varied from 18.4% in Dizangué to 21.7% in Yaoundé, while it was 4.5% in Yaoundé and 12.6% in Dizangué with RDTs. Only abdominal and retro-orbital pains were significantly associated with acute dengue infection. All four dengue serotypes were recorded, with a predominance of DENV-3 (35.45%) and DENV-4 (25.45%). Rapid Diagnostic Tests for either chikungunya or dengue displayed very poor sensitivity. This study further confirms the high endemicity of both dengue and chikungunya in Yaoundé and Dizangué. These data stress the need for active surveillance and the implementation of vector control measures to prevent the occurrence of outbreaks across the country.
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Affiliation(s)
- Stella Mariette Nana-Ndjangwo
- Laboratory of Parasitology and Ecology, Department of Animal Physiology and Ecology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Correspondence: (S.M.N.-N.); (C.A.-N.)
| | - Borel Djiappi-Tchamen
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Vector Borne Diseases Laboratory of the Applied Biology and Ecology Research Unit (VBID-URBEA), Department of Animal Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 067, Cameroon
| | - Ruth Mony
- Laboratory of Parasitology and Ecology, Department of Animal Physiology and Ecology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
| | - Maurice Demanou
- World Health Organization, IST West Africa, Ouagadougou P.O. Box 7019, Burkina Faso
| | - Joyce Keumezeu-Tsafack
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Department of Biological Sciences, University of Douala, Douala P.O. Box 24157, Cameroon
| | - Roland Bamou
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Vector Borne Diseases Laboratory of the Applied Biology and Ecology Research Unit (VBID-URBEA), Department of Animal Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 067, Cameroon
| | - Parfait Awono-Ambene
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
| | - Charles Félix Bilong Bilong
- Laboratory of Parasitology and Ecology, Department of Animal Physiology and Ecology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
| | - Christophe Antonio-Nkondjio
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Vector Biology Liverpool School of Tropical Medicine Pembroke Place, Liverpool L3 5QA, UK
- Correspondence: (S.M.N.-N.); (C.A.-N.)
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9
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Djiappi-Tchamen B, Nana-Ndjangwo MS, Nchoutpouen E, Makoudjou I, Ngangue-Siewe IN, Talipouo A, Mayi MPA, Awono-Ambene P, Wondji C, Tchuinkam T, Antonio-Nkondjio C. Aedes Mosquito Surveillance Using Ovitraps, Sweep Nets, and Biogent Traps in the City of Yaoundé, Cameroon. INSECTS 2022; 13:793. [PMID: 36135494 PMCID: PMC9500714 DOI: 10.3390/insects13090793] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/27/2022] [Accepted: 08/29/2022] [Indexed: 05/07/2023]
Abstract
Arbovirus diseases represent a significant public health problem in Cameroon and vector surveillance is a key component of prevention strategies. However, there is still not enough evidence of the efficacy of different sampling methods used to monitor Aedes mosquito population dynamic in different epidemiological settings. The present study provides data on the evaluation of ovitraps and different adult sampling methods in the city of Yaoundé and its close vicinity. Entomological surveys were carried out from February 2020 to March 2021 in two urban (Obili, Mvan), two peri-urban (Simbock, Ahala), and two rural (Lendom, Elig-essomballa) sites in the city of Yaoundé. The efficacy of three sampling methods, namely ovitraps, Biogent Sentinel trap, and sweep nets, was evaluated. Different ovitrap indices were used to assess the infestation levels across study sites; a general linear model was used to determine if there are statistical differences between positive ovitraps across ecological zones. A total of 16,264 Aedes mosquitoes were collected during entomological surveys. Ovitraps provided the highest mosquito abundance (15,323; 91.14%) and the highest species diversity. Of the five Aedes species collected, Aedes albopictus (59.74%) was the most commonly recorded in both urban and rural settings. Different Aedes species were collected in the same ovitrap. The ovitrap positivity index was high in all sites and varied from 58.3% in Obili in the urban area to 86.08% in Lendom in the rural area. The egg density index varied from 6.42 in Mvan (urban site) to 13.70 in Lendom (rural area). Adult sampling methods recorded mostly Aedes albopictus. The present study supports high infestation of Aedes species in the city of Yaoundé. Ovitraps were highly efficient in detecting Aedes distribution across study sites. The situation calls for regular surveillance and control of Aedes population to prevent sudden occurrence of outbreaks.
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Affiliation(s)
- Borel Djiappi-Tchamen
- Vector Borne Diseases Laboratory of the Research Unit Biology and Applied Ecology (VBID-RUBAE), Department of Animal Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 067, Cameroon
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
| | - Mariette Stella Nana-Ndjangwo
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Laboratory of Parasitology and Ecology, Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
| | - Elysée Nchoutpouen
- Centre for Research in Infectious Disease (CRID), Yaoundé P.O. Box 13591, Cameroon
| | - Idene Makoudjou
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Laboratory of Parasitology and Ecology, Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
| | - Idriss Nasser Ngangue-Siewe
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Laboratory of Biology and Physiology of Animal Organisms, Faculty of Sciences, University of Douala, Douala P.O. Box 24157, Cameroon
| | - Abdou Talipouo
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Laboratory of Parasitology and Ecology, Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
| | - Marie Paul Audrey Mayi
- Vector Borne Diseases Laboratory of the Research Unit Biology and Applied Ecology (VBID-RUBAE), Department of Animal Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 067, Cameroon
| | - Parfait Awono-Ambene
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
| | - Charles Wondji
- Centre for Research in Infectious Disease (CRID), Yaoundé P.O. Box 13591, Cameroon
- Vector Biology Liverpool School of Tropical Medicine Pembroke Place, Liverpool L3 5QA, UK
| | - Timoléon Tchuinkam
- Vector Borne Diseases Laboratory of the Research Unit Biology and Applied Ecology (VBID-RUBAE), Department of Animal Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 067, Cameroon
| | - Christophe Antonio-Nkondjio
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon
- Vector Biology Liverpool School of Tropical Medicine Pembroke Place, Liverpool L3 5QA, UK
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10
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Diallo D, Diouf B, Gaye A, NDiaye EH, Sene NM, Dia I, Diallo M. Dengue vectors in Africa: A review. Heliyon 2022; 8:e09459. [PMID: 35620619 PMCID: PMC9126922 DOI: 10.1016/j.heliyon.2022.e09459] [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: 08/05/2021] [Revised: 11/04/2021] [Accepted: 05/12/2022] [Indexed: 11/25/2022] Open
Abstract
Dengue fever is a mosquito-borne-disease of growing public health importance in Africa. The continuous increase of number and frequency of outbreaks of dengue fever, especially in urban area in Africa underline the need to review the current data available on vectors involved in dengue virus transmission in Africa. Here, we summarized the available data on vectors involved in the transmission of dengue virus in the sylvatic and urban environments, vertical transmission, vector competence studies, and vector control strategies used in Africa. The virus was isolated mainly from Aedes furcifer, Ae. luteocephalus, and Ae. taylori in the sylvatic environment and from Ae. aegypti and Ae. albopictus in the urban areas. Prospective and urgently needed studies on vectors biology, behavior, and alternative control strategies are suggested.
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Affiliation(s)
- Diawo Diallo
- Pôle de Zoologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220, Dakar, Senegal
| | - Babacar Diouf
- Pôle de Zoologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220, Dakar, Senegal
| | - Alioune Gaye
- Pôle de Zoologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220, Dakar, Senegal
| | - El Hadji NDiaye
- Pôle de Zoologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220, Dakar, Senegal
| | - Ndeye Marie Sene
- Pôle de Zoologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220, Dakar, Senegal
| | - Ibrahima Dia
- Pôle de Zoologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220, Dakar, Senegal
| | - Mawlouth Diallo
- Pôle de Zoologie Médicale, Institut Pasteur de Dakar, 36 Avenue Pasteur, BP 220, Dakar, Senegal
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11
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Wijesinghe C, Gunatilake J, Kusumawathie PHD, Sirisena PDNN, Daulagala SWPL, Iqbal BN, Noordeen F. Circulating dengue virus serotypes and vertical transmission in Aedes larvae during outbreak and inter-outbreak seasons in a high dengue risk area of Sri Lanka. Parasit Vectors 2021; 14:614. [PMID: 34949219 PMCID: PMC8705164 DOI: 10.1186/s13071-021-05114-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/02/2021] [Indexed: 11/16/2022] Open
Abstract
Background Spatial and temporal changes in the dengue incidence are associated with multiple factors, such as climate, immunity among a population against dengue viruses (DENV), circulating DENV serotypes and vertical transmission (VT) of DENV in an area at a given time. The level of VT in a specific location has epidemiological implications in terms of viral maintenance in vectors. Identification of the circulating DENV serotypes in both patients and Aedes mosquito larvae in an area may be useful for the early detection of outbreaks. We report here the results of a prospective descriptive study that was conducted to detect the levels of VT in Aedes mosquito larvae and circulating DENV serotypes in patients and Aedes mosquito larvae from December 2015 to March 2017 in an area of Sri Lanka at high risk for dengue. Methods A total of 200 patients with clinically suspected dengue who had been admitted to a tertiary care hospital during a dengue outbreak (3 study periods: December 2015–January 2016, June–August 2016, December 2016–January 2017) and in the inter-outbreak periods (February–May 2016 and September–November 2016) were investigated. Blood samples were drawn from the study participants to test for DENV. The houses of the study participants were visited within 7 days of admission to the hospital, and Aedes larvae were also collected within a radius of 400 m from the houses. The larvae were separately identified to species and then pooled according to each patient’s identification number. Patients’ sera and the Aedes larvae were tested to identify the infecting DENV serotypes using a reverse transcription PCR (RT-PCR) method. Levels of VT in Aedes mosquito larvae were also identified. Results All four DENV serotypes (DENV-1 to -4) were identified in the study area. In the early part of the study (December 2015–February 2016), DENV-3 was predominant and from April 2016 to March 2017, DENV-2 became the most predominant type. Four cases of DENV co-infections were noted during the study period in patients. Interestingly, all four DENV serotypes were detected in Aedes albopictus larvae, which was the prominent immature vectorial form identified throughout the study period in the area, showing 9.8% VT of DENV. With the exception of DENV-4, the other three DENV serotypes were identified in Aedes aegypti larvae with a VT of 8.1%. Conclusion Comparatively high rates of VT of DENV was detected in Ae. albopictus and Ae. aegypti larvae. A shift in the predominant DENV serotype with simultaneous circulation of all four DENV serotypes was identified in the study area from December 2015 to March 2017. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-05114-5.
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Affiliation(s)
- Chandana Wijesinghe
- Teaching Hospital Peradeniya, Peradeniya, 20400, Sri Lanka.,Postgraduate Institute of Science, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | - Jagath Gunatilake
- Postgraduate Institute of Science, University of Peradeniya, Peradeniya, 20400, Sri Lanka.,Department of Geology, Faculty of Science, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | | | - P D N N Sirisena
- Department of Microbiology, Faculty of Medicine, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | - S W P L Daulagala
- Department of Microbiology, Faculty of Medicine, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | - Bushran N Iqbal
- Department of Microbiology, Faculty of Medicine, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | - Faseeha Noordeen
- Department of Microbiology, Faculty of Medicine, University of Peradeniya, Peradeniya, 20400, Sri Lanka.
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12
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Isa I, Ndams IS, Aminu M, Chechet G, Dotzauer A, Simon AY. Genetic diversity of Dengue virus serotypes circulating among Aedes mosquitoes in selected regions of northeastern Nigeria. One Health 2021; 13:100348. [PMID: 34825044 PMCID: PMC8605110 DOI: 10.1016/j.onehlt.2021.100348] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 11/08/2021] [Accepted: 11/08/2021] [Indexed: 11/07/2022] Open
Abstract
The flaviviruses are mosquito borne pathogens that continue to pose a considerable public health risk to animals and humans. The members of this group includes, Dengue virus (DENV), Yellow fever virus (YVF), Japanese encephalitis virus (JEV), West Nile virus (WEV) and Zika virus (ZKV). The DENV mosquito vector is endemic to tropical and subtropical climates, placing ∼40% of the world's population at direct risk of dengue infection. Currently, in Nigeria the status of DENV serotypes circulating among mosquito vectors is unknown. Our study was designed to identify and characterize the DENV serotypes circulating in Aedes mosquito populations collected in selected sites in Nigeria. The mosquitoes were collected and identified morphologically to species level using colored identification keys of Rueda. Generally, each species identified was tested in pools of 20 individuals of each Aedes species. RT-PCR and semi nested PCR were used to detect DENV serotypes in mosquitoes and characterized using Sanger sequencing methods. The results showed that DENV serotypes were detected in 58.54% (24/41) of the pools of Aedes mosquitoes from Mubi, Numan and Yola screened. All DENV1-4 serotypes were detected in Ae. aegypti. While DENV 1, 2 and 4 were detected in Ae. albopictus. And only DENV 2 was detected in Ae. galloisi with DENV4 serotype being reported for the first time in Nigeria. DENV2 (37.8%) was the most detected serotypes, while double and triple co-infections of serotypes were detected in 24.4% of the pools. Phylogenetic analysis revealed a strong evolutionary relatedness of DENV serotypes in our study with that of South and Southeast Asia, North America, and other African countries. This is the first reports on the natural DENV serotypes co-infection among Aedes species pools in Nigeria, which can create possible interaction with other flaviviruses causing animal and human diseases. In addition, our study postulates the possible linkage between DENV serotypes infection and human febrile flu-like disease burden being experienced by host communities in northeastern Nigeria.
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Affiliation(s)
- Ibrahim Isa
- Department of Zoology, Ahmadu Bello University Zaria, Nigeria
| | - Iliya Shehu Ndams
- Department of Zoology, Ahmadu Bello University Zaria, Nigeria.,Africa Centre of Excellence for Neglected Tropical Diseases & Forensic Biotechnology, Ahmadu Bello University Zaria, Nigeria
| | - Maryam Aminu
- Department of Microbiology, Ahmadu Bello University Zaria, Nigeria
| | - Gloria Chechet
- Department of Biochemistry, Ahmadu Bello University Zaria, Nigeria.,Africa Centre of Excellence for Neglected Tropical Diseases & Forensic Biotechnology, Ahmadu Bello University Zaria, Nigeria
| | | | - Ayo Yila Simon
- Africa Centre of Excellence for Neglected Tropical Diseases & Forensic Biotechnology, Ahmadu Bello University Zaria, Nigeria.,Center for Blood Research and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada.,National Centers for Animal Disease Research, Lethbridge Laboratory, Science Branch, Canadian Food Inspection Agency, Government of Canada, Lethbridge, Alberta, Canada
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13
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Simo Tchetgna H, Sado Yousseu F, Kamgang B, Tedjou A, McCall PJ, Wondji CS. Concurrent circulation of dengue serotype 1, 2 and 3 among acute febrile patients in Cameroon. PLoS Negl Trop Dis 2021; 15:e0009860. [PMID: 34695135 PMCID: PMC8568189 DOI: 10.1371/journal.pntd.0009860] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 11/04/2021] [Accepted: 09/28/2021] [Indexed: 11/21/2022] Open
Abstract
Acute febrile patients presenting at hospitals in Douala, Cameroon between July and December 2020, were screened for dengue infections using real time RT-PCR on fragments of the 5’ and 3’ UTR genomic regions. In total, 12.8% (41/320) of cases examined were positive for dengue. Dengue virus 3 (DENV-3) was the most common serotype found (68.3%), followed by DENV-2 (19.5%) and DENV-1 (4.9%). Co-infections of DENV-3 and DENV-2 were found in 3 cases. Jaundice and headache were the most frequent clinical signs associated with infection and 56% (23/41) of the cases were co-infections with malaria. Phylogenetic analysis of the envelope gene identified DENV-1 as belonging to genotype V, DENV-2 to genotype II and DENV-3 to genotype III. The simultaneous occurrence of three serotypes in Douala reveals dengue as a serious public health threat for Cameroon and highlights the need for further epidemiological studies in the major cities of this region. Acute febrile patients presenting at hospitals in Douala, Cameroon between July and December 2020, were screened for dengue infections by Polymerase chain reaction. In total, 12.8% (41/320) of cases examined were infected by dengue virus. Dengue virus 3 (DENV-3) was the most common serotype found (68.3%), followed by DENV-2 (19.5%) and DENV-1 (4.9%). Co-infections of DENV-3 and DENV-2 were found in 3 cases. Jaundice and headache were the most frequent clinical signs associated with infection and 56% (23/41) of the cases were co-infections with malaria. The simultaneous occurrence of three serotypes in Douala reveals dengue as a serious public health threat for Cameroon and highlights the need for further epidemiological studies in the major cities of this region.
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Affiliation(s)
| | - Francine Sado Yousseu
- Centre for Research in Infectious Diseases, Yaoundé, Cameroon
- University of Buéa, Buéa, Cameroon
| | - Basile Kamgang
- Centre for Research in Infectious Diseases, Yaoundé, Cameroon
| | - Armel Tedjou
- Centre for Research in Infectious Diseases, Yaoundé, Cameroon
- University of Yaoundé I, Yaoundé, Cameroon
| | - Philip J. McCall
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Charles S. Wondji
- Centre for Research in Infectious Diseases, Yaoundé, Cameroon
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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14
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Bamou R, Mayi MPA, Djiappi-Tchamen B, Nana-Ndjangwo SM, Nchoutpouen E, Cornel AJ, Awono-Ambene P, Parola P, Tchuinkam T, Antonio-Nkondjio C. An update on the mosquito fauna and mosquito-borne diseases distribution in Cameroon. Parasit Vectors 2021; 14:527. [PMID: 34635176 PMCID: PMC8507310 DOI: 10.1186/s13071-021-04950-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 08/12/2021] [Indexed: 11/10/2022] Open
Abstract
The expansion of mosquito-borne diseases such as dengue, yellow fever, and chikungunya in the past 15 years has ignited the need for active surveillance of common and neglected mosquito-borne infectious diseases. The surveillance should be designed to detect diseases and to provide relevant field-based data for developing and implementing effective control measures to prevent outbreaks before significant public health consequences can occur. Mosquitoes are important vectors of human and animal pathogens, and knowledge on their biodiversity and distribution in the Afrotropical region is needed for the development of evidence-based vector control strategies. Following a comprehensive literature search, an inventory of the diversity and distribution of mosquitoes as well as the different mosquito-borne diseases found in Cameroon was made. A total of 290 publications/reports and the mosquito catalogue website were consulted for the review. To date, about 307 species, four subspecies and one putative new species of Culicidae, comprising 60 species and one putative new species of Anopheles, 67 species and two subspecies of Culex, 77 species and one subspecies of Aedes, 31 species and one subspecies of Eretmapodites, two Mansonia, eight Coquillettidia, and 62 species with unknown medical and veterinary importance (Toxorhynchites, Uranotaenia, Mimomyia, Malaya, Hodgesia, Ficalbia, Orthopodomyia, Aedeomyia, and Culiseta and Lutzia) have been collected in Cameroon. Multiple mosquito species implicated in the transmission of pathogens within Anopheles, Culex, Aedes, Eretmapodites, Mansonia, and Coquillettidia have been reported in Cameroon. Furthermore, the presence of 26 human and zoonotic arboviral diseases, one helminthic disease, and two protozoal diseases has been reported. Information on the bionomics, taxonomy, and distribution of mosquito species will be useful for the development of integrated vector management programmes for the surveillance and elimination of mosquito-borne diseases in Cameroon. ![]()
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Affiliation(s)
- Roland Bamou
- Vector Borne Diseases Laboratory of the Biology and Applied Ecology Research Unit (VBID-URBEA), Department of Animal Biology, Faculty of Science of the University of Dschang, Dschang, Cameroon. .,Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, Cameroon. .,Aix Marseille Univ, IRD, SSA, AP-HM, UMR Vecteurs-Infections Tropicales et Méditerranéennes (VITROME), Marseille, France. .,IHU Méditerranée Infection, Marseille, France.
| | - Marie Paul Audrey Mayi
- Vector Borne Diseases Laboratory of the Biology and Applied Ecology Research Unit (VBID-URBEA), Department of Animal Biology, Faculty of Science of the University of Dschang, Dschang, Cameroon
| | - Borel Djiappi-Tchamen
- Vector Borne Diseases Laboratory of the Biology and Applied Ecology Research Unit (VBID-URBEA), Department of Animal Biology, Faculty of Science of the University of Dschang, Dschang, Cameroon.,Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, Cameroon
| | - Stella Mariette Nana-Ndjangwo
- Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, Cameroon.,Laboratoire de Parasitologie et d'écologie, Université de Yaoundé 1, Yaoundé, Cameroun
| | - Elysée Nchoutpouen
- Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, Cameroon
| | - Antony John Cornel
- Department of Entomology and Nematology, Mosquito Control Research Laboratory, University of California, Davis, California, USA
| | - Parfait Awono-Ambene
- Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, Cameroon
| | - Phillipe Parola
- Aix Marseille Univ, IRD, SSA, AP-HM, UMR Vecteurs-Infections Tropicales et Méditerranéennes (VITROME), Marseille, France.,IHU Méditerranée Infection, Marseille, France
| | - Timoléon Tchuinkam
- Vector Borne Diseases Laboratory of the Biology and Applied Ecology Research Unit (VBID-URBEA), Department of Animal Biology, Faculty of Science of the University of Dschang, Dschang, Cameroon
| | - Christophe Antonio-Nkondjio
- Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé, Cameroon.,Vector Biology Liverpool School of Tropical Medicine, Liverpool, UK
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15
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Djiappi-Tchamen B, Nana-Ndjangwo MS, Tchuinkam T, Makoudjou I, Nchoutpouen E, Kopya E, Talipouo A, Bamou R, Mayi MPA, Awono-Ambene P, Wondji C, Antonio-Nkondjio C. Aedes Mosquito Distribution along a Transect from Rural to Urban Settings in Yaoundé, Cameroon. INSECTS 2021; 12:819. [PMID: 34564259 PMCID: PMC8471432 DOI: 10.3390/insects12090819] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/25/2021] [Accepted: 09/07/2021] [Indexed: 12/22/2022]
Abstract
INTRODUCTION The surveillance of mosquito vectors is important for the control of arboviruses diseases worldwide. Detailed information on the bionomics and distribution of their main vectors, Aedes aegypti and Aedes albopictus, is essential for assessing disease transmission risk and for better planning of control interventions. METHODS Entomological surveys were carried out from November 2019 to November 2020 in six localities of Yaoundé city following a transect from urban to rural settings: two urban (Obili, Mvan), two peri-urban (Simbock, Ahala) and two rural areas (Lendom, Elig-essomballa)-during rainy and dry seasons. All water containers were inspected. Aedes mosquito abundance, species distribution and seasonal distribution patterns were compared using generalized linear models. Stegomyia indexes were estimated to determine the risk of arbovirus transmission. RESULTS A total of 6332 mosquitoes larvae were collected (2342 in urban areas, 1694 in peri-urban areas and 2296 in rural sites). Aedes species recorded included Ae. albopictus, Ae. aegytpi, Ae. simpsoni and Aedes spp. High mosquito abundance was registered in the rainy season (4706) compared to the dry season (1626) (p < 0.0001). Ae. albopictus was the most abundant Aedes species in urban (96.89%) and peri-urban (95.09%) sites whereas Ae. aegypti was more prevalent in rural sites (68.56%) (p < 0.0001). Both species were found together in 71 larval habitats. Ae. albopictus was mostly found in discarded tires (42.51%), whereas Ae. aegypti was more prevalent in plastic containers used for storing water (65.87%). The majority of Aedes mosquitoes' breeding places were situated close to human dwellings (0-10 m). CONCLUSION Uncontrolled urbanization seems to greatly favour the presence of Aedes mosquito species around human dwellings in Yaoundé. Controlling Aedes mosquito distribution is becoming urgent to reduce the risk of arbovirus outbreaks in the city of Yaoundé.
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Affiliation(s)
- Borel Djiappi-Tchamen
- Vector Borne Diseases Laboratory of the Research Unit Biology and Applied Ecology (VBID-RUBAE), Department of Animal Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 067, Cameroon; (B.D.-T.); (T.T.); (R.B.); (M.P.A.M.)
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon; (M.S.N.-N.); (I.M.); (E.K.); (A.T.); (P.A.-A.)
| | - Mariette Stella Nana-Ndjangwo
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon; (M.S.N.-N.); (I.M.); (E.K.); (A.T.); (P.A.-A.)
- Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
| | - Timoléon Tchuinkam
- Vector Borne Diseases Laboratory of the Research Unit Biology and Applied Ecology (VBID-RUBAE), Department of Animal Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 067, Cameroon; (B.D.-T.); (T.T.); (R.B.); (M.P.A.M.)
| | - Idene Makoudjou
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon; (M.S.N.-N.); (I.M.); (E.K.); (A.T.); (P.A.-A.)
- Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
| | - Elysée Nchoutpouen
- Centre for Research in Infectious Disease (CRID), Yaoundé P.O. Box 13591, Cameroon; (E.N.); (C.W.)
| | - Edmond Kopya
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon; (M.S.N.-N.); (I.M.); (E.K.); (A.T.); (P.A.-A.)
- Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
| | - Abdou Talipouo
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon; (M.S.N.-N.); (I.M.); (E.K.); (A.T.); (P.A.-A.)
- Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, Yaoundé P.O. Box 337, Cameroon
| | - Roland Bamou
- Vector Borne Diseases Laboratory of the Research Unit Biology and Applied Ecology (VBID-RUBAE), Department of Animal Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 067, Cameroon; (B.D.-T.); (T.T.); (R.B.); (M.P.A.M.)
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon; (M.S.N.-N.); (I.M.); (E.K.); (A.T.); (P.A.-A.)
| | - Marie Paul Audrey Mayi
- Vector Borne Diseases Laboratory of the Research Unit Biology and Applied Ecology (VBID-RUBAE), Department of Animal Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 067, Cameroon; (B.D.-T.); (T.T.); (R.B.); (M.P.A.M.)
| | - Parfait Awono-Ambene
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon; (M.S.N.-N.); (I.M.); (E.K.); (A.T.); (P.A.-A.)
| | - Charles Wondji
- Centre for Research in Infectious Disease (CRID), Yaoundé P.O. Box 13591, Cameroon; (E.N.); (C.W.)
- Vector Biology Liverpool School of Tropical Medicine Pembroke Place, Liverpool L3 5QA, UK
| | - Christophe Antonio-Nkondjio
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la Lutte Contre les Endémies en Afrique Centrale (OCEAC), Yaoundé P.O. Box 288, Cameroon; (M.S.N.-N.); (I.M.); (E.K.); (A.T.); (P.A.-A.)
- Vector Biology Liverpool School of Tropical Medicine Pembroke Place, Liverpool L3 5QA, UK
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16
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Yan R, Zhou Q, Xu Z, Wu Y, Zhu G, Wang M, Guo Y, Dong K, Chen M. Pyrethrins elicit olfactory response and spatial repellency in Aedes albopictus. PEST MANAGEMENT SCIENCE 2021; 77:3706-3712. [PMID: 33798266 DOI: 10.1002/ps.6390] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 02/08/2021] [Accepted: 04/02/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Pyrethrum from dry flowers of Chrysanthemum is a well-known botanical insecticide and repellent. Its insecticidal activity attributes to its six insecticidal esters, collectively known as pyrethrins. Pyrethrins and its synthetic analogs pyrethroids exert their toxic action by modifying the function of voltage-gated sodium channels. Aside from insecticidal activity, pyrethrum has also been used to repel mosquitoes for centuries. Today, pyrethrum continues to be used as an active ingredient in mosquito coils and other mosquito-repellent devices globally. However, the mechanism of pyrethrum repellency remains largely unknown. RESULTS Here we report that pyrethrum vapor induced spatial (non-contact) repellency in Aedes albopictus, a major vector of dengue and West Nile viruses. Using electroantennogram (EAG) recordings from adult antennae, we found that pyrethrum elicited EAG response in a dose-dependent manner. We then isolated the six insecticidal esters, pyrethrins I and II, cinerins I and II, jasmolins I and II from pyrethrum extract and discovered that five of the six esters, except jasmolin I, all elicited EAG responses. Furthermore, pyrethrins I and II, cinerin II and jasmolin II induced repellency, whereas cinerin I and jasmolin I did not. CONCLUSION Of the six pyrethrins, four of them, pyrethrins I and II, cinerin II and jasmolin II, activate olfactory-receptor neurons and elicit spatial repellency in Ae. albopictus. Our study provided a foundation for future structure-function studies of pyrethrins, their cognate olfactory receptors and efficacies of repellency and for the development of new and more effective mosquito repellents for controlling vector-borne human diseases. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Ru Yan
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Qiaoling Zhou
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Zhanyi Xu
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Yuyan Wu
- Institute for Communicable Disease Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Guonian Zhu
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Mengcen Wang
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Yirong Guo
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Ke Dong
- Department of Entomology, Genetics and Neuroscience Programs, Michigan State University, East Lansing, MI, USA
- Department of Biology, Duke University, Durham, NC, USA
| | - Mengli Chen
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
- College of Agricultural and Food Sciences, Zhejiang A&F University, Hangzhou, China
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17
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Life as a Vector of Dengue Virus: The Antioxidant Strategy of Mosquito Cells to Survive Viral Infection. Antioxidants (Basel) 2021; 10:antiox10030395. [PMID: 33807863 PMCID: PMC8000470 DOI: 10.3390/antiox10030395] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/27/2021] [Accepted: 03/01/2021] [Indexed: 12/15/2022] Open
Abstract
Dengue fever is a mosquito-borne viral disease of increasing global importance. The disease has caused heavy burdens due to frequent outbreaks in tropical and subtropical areas of the world. The dengue virus (DENV) is generally transmitted between human hosts via the bite of a mosquito vector, primarily Aedes aegypti and Ae. albopictus as a minor species. It is known that the virus needs to alternately infect mosquito and human cells. DENV-induced cell death is relevant to the pathogenesis in humans as infected cells undergo apoptosis. In contrast, mosquito cells mostly survive the infection; this allows infected mosquitoes to remain healthy enough to serve as an efficient vector in nature. Overexpression of antioxidant genes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutaredoxin (Grx), thioredoxin (Trx), and protein disulfide isomerase (PDI) have been detected in DENV2-infected mosquito cells. Additional antioxidants, including GST, eukaryotic translation initiation factor 5A (eIF5a), and p53 isoform 2 (p53-2), and perhaps some others, are also involved in creating an intracellular environment suitable for cell replication and viral infection. Antiapoptotic effects involving inhibitor of apoptosis (IAP) upregulation and subsequent elevation of caspase-9 and caspase-3 activities also play crucial roles in the ability of mosquito cells to survive DENV infection. This article focused on the effects of intracellular responses in mosquito cells to infection primarily by DENVs. It may provide more information to better understand virus/cell interactions that can possibly elucidate the evolutionary pathway that led to the mosquito becoming a vector.
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18
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Dolan PT, Taguwa S, Rangel MA, Acevedo A, Hagai T, Andino R, Frydman J. Principles of dengue virus evolvability derived from genotype-fitness maps in human and mosquito cells. eLife 2021; 10:e61921. [PMID: 33491648 PMCID: PMC7880689 DOI: 10.7554/elife.61921] [Citation(s) in RCA: 12] [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] [Received: 08/08/2020] [Accepted: 01/24/2021] [Indexed: 01/11/2023] Open
Abstract
Dengue virus (DENV) cycles between mosquito and mammalian hosts. To examine how DENV populations adapt to these different host environments, we used serial passage in human and mosquito cell lines and estimated fitness effects for all single-nucleotide variants in these populations using ultra-deep sequencing. This allowed us to determine the contributions of beneficial and deleterious mutations to the collective fitness of the population. Our analysis revealed that the continuous influx of a large burden of deleterious mutations counterbalances the effect of rare, host-specific beneficial mutations to shape the path of adaptation. Beneficial mutations preferentially map to intrinsically disordered domains in the viral proteome and cluster to defined regions in the genome. These phenotypically redundant adaptive alleles may facilitate host-specific DENV adaptation. Importantly, the evolutionary constraints described in our simple system mirror trends observed across DENV and Zika strains, indicating it recapitulates key biophysical and biological constraints shaping long-term viral evolution.
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Affiliation(s)
- Patrick T Dolan
- Stanford University, Department of BiologyStanfordUnited States
- University of California, Microbiology and Immunology, San FranciscoSan FranciscoUnited States
| | - Shuhei Taguwa
- Stanford University, Department of BiologyStanfordUnited States
| | | | - Ashley Acevedo
- University of California, Microbiology and Immunology, San FranciscoSan FranciscoUnited States
| | - Tzachi Hagai
- Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv UniversityTel AvivIsrael
| | - Raul Andino
- University of California, Microbiology and Immunology, San FranciscoSan FranciscoUnited States
| | - Judith Frydman
- Stanford University, Department of BiologyStanfordUnited States
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19
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Yougang AP, Kamgang B, Bahun TAW, Tedjou AN, Nguiffo-Nguete D, Njiokou F, Wondji CS. First detection of F1534C knockdown resistance mutation in Aedes aegypti (Diptera: Culicidae) from Cameroon. Infect Dis Poverty 2020; 9:152. [PMID: 33138860 PMCID: PMC7607635 DOI: 10.1186/s40249-020-00769-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 10/19/2020] [Indexed: 12/13/2022] Open
Abstract
Background Aedes borne viral diseases, notably dengue, are increasingly reported in Cameroon with Aedes aegypti being a major vector. Data on insecticide resistance of this vector and underlying mechanisms needed for outbreak preparedness remain scarce in Cameroon. Here, we present the nationwide distribution of insecticide resistance in Ae. aegypti and investigate the potential resistance mechanisms involved. Methods Immature stages of Ae. aegypti were collected between March and July 2017 in 13 locations across Cameroon and reared until G1/G2/G3 generation. Larval, adult bioassays, and piperonyl butoxide (PBO) synergist assays were carried out according to World Health Organization guidelines. F1534C mutation was genotyped using allele specific polymerase chain reaction in field collected adults (Go) and the polymorphism of the sodium channel gene was assessed. The χ2 test was used to compare the mortality rate between bioassays with insecticides only and bioassays after preexposure to PBO synergist. Results Larval bioassay revealed that all the three populations tested with temephos were susceptible. Adult bioassays showed a good level of susceptibility toward both pyrethroids tested, 0.25% permethrin and 0.05% deltamethrin, with six out of 10 populations susceptible. However, two populations (Douala and Edéa) were resistant (deltamethrin [73.2–92.5% mortality], permethrin [2.6–76.3% mortality]). The resistance to 4% dichlorodiphenyltrichloroethane was observed in four out of 10 populations tested (16.8–87.1% mortality). Resistance was also reported to carbamates including 0.1% propoxur (60.8–87.1% mortality) and to 0.1% bendiocarb (82.9% mortality). All populations tested were fully susceptible to 1% fenitrothion. A partial recovery of susceptibility was observed in the pyrethroid resistant population of Douala after pre-exposed to PBO suggesting the implication of cytochrome P450 monoxygenases permethrin resistance. Genotyping and sequencing detected the F1534C kdr mutation in the two pyrethroid resistant locations of Edéa and Douala, with allelic frequency of 3.3% and 33.3% respectively. However, the high genetic diversity of the sodium channel gene supports the recent introduction of this mutation in Cameroon. Conclusions This study revealed the contrasting resistance profiles to insecticides of Ae. aegypti populations in Cameroon suggesting that, instead of a unique nationwide control approach, a regionally adapted strategy will be needed to control this vector. The localised distribution of the F1534C kdr mutation supports this region-specific control strategy.
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Affiliation(s)
- Aurelie P Yougang
- Centre for Research in Infectious Diseases, P.O. Box 13591, Yaoundé, Cameroon.,Parasitology and Ecology Laboratory, Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
| | - Basile Kamgang
- Centre for Research in Infectious Diseases, P.O. Box 13591, Yaoundé, Cameroon.
| | - Theodel A Wilson Bahun
- Centre for Research in Infectious Diseases, P.O. Box 13591, Yaoundé, Cameroon.,Laboratory of Vertebrate and Invertebrate Bioecology, Faculty of Science and Technology, Marien-Ngouabi University, Brazzaville, Congo
| | - Armel N Tedjou
- Centre for Research in Infectious Diseases, P.O. Box 13591, Yaoundé, Cameroon.,Parasitology and Ecology Laboratory, Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
| | - Daniel Nguiffo-Nguete
- Centre for Research in Infectious Diseases, P.O. Box 13591, Yaoundé, Cameroon.,Laboratory of Biology and Applied Ecology, Department of Animal Biology, Faculty of Science, University of Dschang, P.O. Box 96, Dschang, Cameroon
| | - Flobert Njiokou
- Parasitology and Ecology Laboratory, Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, P.O. Box 812, Yaoundé, Cameroon
| | - Charles S Wondji
- Centre for Research in Infectious Diseases, P.O. Box 13591, Yaoundé, Cameroon.,Liverpool School of Tropical Medicine, Pembroke place, Liverpool, L3 5QA, UK
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20
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Bohers C, Mousson L, Madec Y, Vazeille M, Rhim A, M’ghirbi Y, Bouattour A, Failloux AB. The recently introduced Aedes albopictus in Tunisia has the potential to transmit chikungunya, dengue and Zika viruses. PLoS Negl Trop Dis 2020; 14:e0008475. [PMID: 33007002 PMCID: PMC7556531 DOI: 10.1371/journal.pntd.0008475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 10/14/2020] [Accepted: 06/11/2020] [Indexed: 12/26/2022] Open
Abstract
The mosquito Aedes albopictus was detected for the first time in Tunisia in 2018. With its establishment in the capital city of Tunis, local health authorities fear the introduction of new human arboviral diseases, like what happened in Europe with unexpected local cases of chikungunya, dengue and Zika. Even though this mosquito is competent to transmit the arboviruses mentioned above, the transmission level will vary depending on the couple, mosquito population and virus genotype. Here, we assessed the vector competence of Ae. albopictus Tunisia by experimental infections with chikungunya (CHIKV), dengue (DENV), and Zika (ZIKV) viruses. We found that Ae. albopictus Tunisia was highly competent for CHIKV (transmission efficiency of 25% at 21 post-infection) and to a lesser extent, for ZIKV (8.7%) and DENV (8.3%). Virus was detected in mosquito saliva at day 3 (CHIKV), day 10 (ZIKV) and day 21 (DENV) post-infection. These results suggest that the risk of emergence of chikungunya is the highest imposing a more sustained surveillance to limit Ae. albopictus populations in densely populated urban dwellings and at the entry points of travelers returning from CHIKV-endemic regions.
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Affiliation(s)
- Chloé Bohers
- Institut Pasteur, Department of Virology, Arboviruses and Insect Vectors, Paris, France
| | - Laurence Mousson
- Institut Pasteur, Department of Virology, Arboviruses and Insect Vectors, Paris, France
| | - Yoann Madec
- Institut Pasteur, Department of Global Health, Epidemiology of Emerging Diseases, Paris, France
| | - Marie Vazeille
- Institut Pasteur, Department of Virology, Arboviruses and Insect Vectors, Paris, France
| | - Adel Rhim
- Laboratoire Virus, Vecteurs et Hôtes, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis-Belvédère, Tunisia
| | - Youmna M’ghirbi
- Laboratoire Virus, Vecteurs et Hôtes, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis-Belvédère, Tunisia
| | - Ali Bouattour
- Laboratoire Virus, Vecteurs et Hôtes, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis-Belvédère, Tunisia
| | - Anna-Bella Failloux
- Institut Pasteur, Department of Virology, Arboviruses and Insect Vectors, Paris, France
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Wilson-Bahun TA, Kamgang B, Lenga A, Wondji CS. Larval ecology and infestation indices of two major arbovirus vectors, Aedes aegypti and Aedes albopictus (Diptera: Culicidae), in Brazzaville, the capital city of the Republic of the Congo. Parasit Vectors 2020; 13:492. [PMID: 32977841 PMCID: PMC7519569 DOI: 10.1186/s13071-020-04374-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 09/20/2020] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Invasive mosquito species, such as Aedes albopictus in Congo can affect the distribution of native species, changing the vector composition and pattern of disease transmission. Here, we comparatively establish the geographical distribution and larval habitat preference of Ae. aegypti and Ae. albopictus and the risk of arbovirus disease outbreaks using Stegomyia indices in the city of Brazzaville, the capital of the Republic of the Congo. METHODS Human dwelling surveys of water-holding containers for immature stages of Aedes was carried out in December 2017 in Brazzaville through a random cluster sampling method. A total of 268 human dwellings distributed in 9 boroughs and 27 neighbourhoods were surveyed across the city. RESULTS Overall, 455 potential larval habitats were surveyed. Both Ae. aegypti and Ae. albopictus were collected across the city with an overall high prevalence of Ae. aegypti (53.1%) compared to Ae. albopictus (46.9%). Geographical distribution analysis showed that Ae. aegypti was more abundant (mean = 6.6 ± 1.4) in neighbourhoods located in downtown, while the abundance of Ae. albopictus was low (mean = 3.5 ± 0.6) in suburbs. Peridomestic containers, especially discarded tanks, were the most strongly colonized productive larval habitat for both mosquito species with the prevalence of 56.4% and 53.1% for Ae. aegypti and Ae. albopictus, respectively. Globally, the house index (HI), Breteau index (BI) and container index (CI) were high for Ae. aegypti (26.6%, 38.4% and 22.6%) and Ae. albopictus (33.3%, 49.6% and 26.6%) compared to the transmission risk threshold (5%, 5% and 20%) established by the WHO/PAHO. Overall, pupae-based indices (the pupae index and the pupae per person index) were not significantly different between Ae. aegypti (273.4% and 23.2%) and Ae. albopictus (228.8% and 19.5%). CONCLUSIONS The findings of this study suggest a high risk for transmission of arbovirus diseases in Brazzaville and call for an urgent need to implement vector control strategies against these vectors in the Republic of the Congo.
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Affiliation(s)
- Theodel A Wilson-Bahun
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13591, Yaoundé, Cameroon.,Laboratory of Biodiversity and Animal Ecology, Department of Animal Biology and Physiology, Faculty of Sciences and Technology, Marien Ngouabi University, P.O. Box 69, Brazzaville, Congo
| | - Basile Kamgang
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13591, Yaoundé, Cameroon.
| | - Arsène Lenga
- Laboratory of Biodiversity and Animal Ecology, Department of Animal Biology and Physiology, Faculty of Sciences and Technology, Marien Ngouabi University, P.O. Box 69, Brazzaville, Congo
| | - Charles S Wondji
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13591, Yaoundé, Cameroon.,Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
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22
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Tedjou AN, Kamgang B, Yougang AP, Wilson-Bahun TA, Njiokou F, Wondji CS. Patterns of Ecological Adaptation of Aedes aegypti and Aedes albopictus and Stegomyia Indices Highlight the Potential Risk of Arbovirus Transmission in Yaoundé, the Capital City of Cameroon. Pathogens 2020; 9:pathogens9060491. [PMID: 32575721 PMCID: PMC7350347 DOI: 10.3390/pathogens9060491] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 06/17/2020] [Indexed: 12/12/2022] Open
Abstract
The dynamic of arbovirus vectors such as Aedes aegypti and Ae. albopictus remains poorly understood in large cities in central Africa. Here, we compared the larval ecology, geographical distribution and degree of infestation of Ae. aegypti and Ae. albopictus in Yaoundé, the capital city of Cameroon, and estimated their Stegomyia indices revealing a significant potential risk of arbovirus transmission. An entomological survey was conducted in April-May 2018 in a cluster of houses randomly selected. Each selected house was inspected, the number of inhabitants was recorded, and potential and positive containers for Aedes were characterized. Stegomyia and pupae-based indices were estimated. Overall, 447 houses and 954 containers were inspected comprising 10,801 immature stages of Aedes with 84.95% of Ae. albopictus and 15.05% of Ae. aegypti. Both species bred mainly in discarded tanks and used tyres, associated with turbid water and the presence of plant debris inside containers. Aedes albopictus was the most prevalent species in almost all neighbourhoods. The house index, Breteau index, and container index were higher for Ae. albopictus (38.26%, 71.81%, and 29.61%) compared to those of Ae. aegypti (25.73%, 40.93%, and 16.88%). These indices are high compared to the thresholds established by Pan American Health Organization and World Health Organization, which suggests a high potential risk of arbovirus transmission.
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Affiliation(s)
- Armel N. Tedjou
- Department of Medical Entomology, Centre for Research in Infectious Diseases, 15391 Yaoundé, Cameroon; (A.P.Y.); (T.A.W.-B.); (C.S.W.)
- Department of Animal Biology and Physiology, Faculty of Sciences, University of Yaoundé I, 812 Yaoundé, Cameroon;
- Correspondence: (A.N.T.); (B.K.)
| | - Basile Kamgang
- Department of Medical Entomology, Centre for Research in Infectious Diseases, 15391 Yaoundé, Cameroon; (A.P.Y.); (T.A.W.-B.); (C.S.W.)
- Correspondence: (A.N.T.); (B.K.)
| | - Aurélie P. Yougang
- Department of Medical Entomology, Centre for Research in Infectious Diseases, 15391 Yaoundé, Cameroon; (A.P.Y.); (T.A.W.-B.); (C.S.W.)
- Department of Animal Biology and Physiology, Faculty of Sciences, University of Yaoundé I, 812 Yaoundé, Cameroon;
| | - Theodel A. Wilson-Bahun
- Department of Medical Entomology, Centre for Research in Infectious Diseases, 15391 Yaoundé, Cameroon; (A.P.Y.); (T.A.W.-B.); (C.S.W.)
- Department of Animal Biology and Physiology, Faculty of Sciences and Technology, Marien Ngouabi University, Brazzaville, Congo
| | - Flobert Njiokou
- Department of Animal Biology and Physiology, Faculty of Sciences, University of Yaoundé I, 812 Yaoundé, Cameroon;
| | - Charles S. Wondji
- Department of Medical Entomology, Centre for Research in Infectious Diseases, 15391 Yaoundé, Cameroon; (A.P.Y.); (T.A.W.-B.); (C.S.W.)
- Vector Biology Department, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
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Yougang AP, Kamgang B, Tedjou AN, Wilson-Bahun TA, Njiokou F, Wondji CS. Nationwide profiling of insecticide resistance in Aedes albopictus (Diptera: Culicidae) in Cameroon. PLoS One 2020; 15:e0234572. [PMID: 32555588 PMCID: PMC7302487 DOI: 10.1371/journal.pone.0234572] [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: 03/25/2020] [Accepted: 05/28/2020] [Indexed: 12/16/2022] Open
Abstract
The Asian mosquito, Aedes albopictus (Skuse), is an invasive mosquito which has become one of the most important vectors of dengue, Zika, and chikungunya viruses worldwide. This species was reported for the first time in Cameroon in early 2000s and became the dominant Aedes species in the urban areas in the southern part of Cameroon but remain poorly characterized. Here, we assessed the susceptibility profile of A. albopictus collected throughout Cameroon and investigated the potential resistance mechanisms involved. Immature stages of A. albopictus were collected between March and July 2017 in 15 locations across Cameroon and reared until G1/G2 generation. Larval, adult bioassays, and synergists [piperonyl butoxide (PBO) and diethyl maleate (DEM)] assays were carried out according to WHO recommendations. F1534C mutation was genotyped in field collected adults (Go) using allele specific PCR. All tested populations were susceptible to both larvicides, temephos and Bacillus thuringiensis israelensis (Bti), after larval bioassays. Adult bioassays revealed a high level of resistance of A. albopictus to 4% DDT with mortality rates ranging from 12.42% in Bafang to 75.04% in Kumba. The resistance was reported also in 0.05% deltamethrin, 0.25% permethrin, and 0.1% propoxur in some locations. A loss of susceptibility to 0.1% bendiocarb was found in one of three populations analysed. A full susceptibility to 1% fenitrothion were observed across the country. A full recovery or partial of susceptibility was observed in A. albopictus when pre-exposed to PBO or DEM and then to DDT and permethrin, respectively. The F1534C kdr mutation was not detected in A. albopictus. This study showed that the susceptibility profile of A. albopictus to insecticide vary according to the sampling location and insecticides used. These findings are useful to planning vector control program against arbovirus vectors in Cameroon and can be used as baseline data for further researches.
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Affiliation(s)
- Aurelie P. Yougang
- Centre for Research in Infectious Diseases, Yaoundé, Cameroon
- Department of Animal Biology and Physiology, Parasitology and Ecology Laboratory, Faculty of Science, University of Yaoundé 1, Yaoundé, Cameroon
- * E-mail: (APY); (BK)
| | - Basile Kamgang
- Centre for Research in Infectious Diseases, Yaoundé, Cameroon
- * E-mail: (APY); (BK)
| | - Armel N. Tedjou
- Centre for Research in Infectious Diseases, Yaoundé, Cameroon
- Department of Animal Biology and Physiology, Parasitology and Ecology Laboratory, Faculty of Science, University of Yaoundé 1, Yaoundé, Cameroon
| | - Theodel A. Wilson-Bahun
- Centre for Research in Infectious Diseases, Yaoundé, Cameroon
- Laboratory of vertebrate and invertebrate bioecology, Faculty of Science and Technology, Marien-Ngouabi University, Brazzaville, Congo
| | - Flobert Njiokou
- Department of Animal Biology and Physiology, Parasitology and Ecology Laboratory, Faculty of Science, University of Yaoundé 1, Yaoundé, Cameroon
| | - Charles S. Wondji
- Centre for Research in Infectious Diseases, Yaoundé, Cameroon
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Habitat and Seasonality Affect Mosquito Community Composition in the West Region of Cameroon. INSECTS 2020; 11:insects11050312. [PMID: 32429075 PMCID: PMC7291174 DOI: 10.3390/insects11050312] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/09/2020] [Accepted: 05/12/2020] [Indexed: 12/20/2022]
Abstract
To identify potential sylvatic, urban and bridge-vectors that can be involved in current or future virus spillover from wild to more urbanised areas, entomological field surveys were conducted in rural, peri-urban and urban areas spanning the rainy and dry seasons in western Cameroon. A total of 2650 mosquitoes belonging to 37 species and eight genera were collected. Mosquito species richness was significantly influenced by the specific combination of the habitat type and the season. The highest species richness was found in the peri-urban area (S = 30, Chao1 = 121 ± 50.63, ACE = 51.97 ± 3.88) during the dry season (S = 28, Chao1 = 64 ± 25.7, ACE = 38.33 ± 3.1). Aedes (Ae.) africanus and Culex (Cx.) moucheti were only found in the rural and peri-urban areas, while Cx. pipiens s.l. and Ae. aegypti were only found in the urban area. Cx. (Culiciomyia) spp., Cx. duttoni and Ae. albopictus were caught in the three habitat types. Importantly, approximately 52% of the mosquito species collected in this study have been implicated in the transmission of diverse arboviruses. This entomological survey provides a catalogue of the different mosquito species that may be involved in the transmission of arboviruses. Further investigations are needed to study the vectorial capacity of each mosquito species in arbovirus transmission.
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O’Connor O, Calvez E, Inizan C, Pocquet N, Richard V, Dupont-Rouzeyrol M. Vector competence of Aedes aegypti from New Caledonia for the four recent circulating dengue virus serotypes. PLoS Negl Trop Dis 2020; 14:e0008303. [PMID: 32407315 PMCID: PMC7252670 DOI: 10.1371/journal.pntd.0008303] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 05/27/2020] [Accepted: 04/17/2020] [Indexed: 12/21/2022] Open
Abstract
In New Caledonia (NC), Aedes aegypti is the only proven vector of dengue virus (DENV), which is the most prevalent arbovirosis in NC. Since World War II, the four DENV serotypes have circulated regularly in NC. The epidemiological profile, however, has evolved over the last ten years, with the persistence of DENV-1 circulation and the co-circulation of several DENV serotypes. The current study evaluated the ability of Ae. aegypti from NC to transmit four DENV serotypes (and two DENV-1 genotypes) isolated during recent outbreaks in NC. An Ae. aegypti F1 generation was twice independently orally challenged with each DENV strain (107 FFU/ml). Infection, dissemination and transmission rates and transmission efficiency were measured at day 7 and 14 post-exposure, as well as the quantity of infectious virus particles. Mosquito infection was observed as early as 7 days post-infection. Infection rates between 18 and 58% were measured for all DENV serotypes/genotypes tested. Although dissemination rates ranged from 78 to 100%, transmission efficiencies were low, with values not exceeding 21% at 14 days post-infection for all DENV strains. This study shows that NC Ae. aegypti are moderately competent for DENV in laboratory conditions. In link with epidemiological data, these results suggest implication of other factors in the sustained circulation of DENV-1 in New Caledonia. Aedes aegypti is the only known vector for dengue virus (DENV) in New Caledonia (NC). DENV are divided into four serotypes (DENV-1 to -4), based on their antigenic properties, these being subdivided into different genotypes. All four DENV serotypes have regularly circulated in New Caledonia in the past. An unusual persistence of DENV-1 has been observed during the last ten years, suggesting a possible preferential transmission of this DENV serotype by Ae. aegypti. In this study, we examine for the first time the ability of Ae. aegypti from New Caledonia to transmit the four circulating DENV serotypes, and more precisely two genotypes of DENV-1. Our results demonstrate that this vector is moderately competent for DENV, with slight differences observed between DENV serotype/genotype in terms of transmission. These findings suggest that other factors are at play in the sustained circulation of DENV-1 and that further vector-virus interactions studies should be undertaken to better understand the DENV epidemiological profile in NC.
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Affiliation(s)
- Olivia O’Connor
- Institut Pasteur de Nouvelle-Calédonie, URE Dengue et Arboviroses, Institut Pasteur International Network, Noumea, New Caledonia
- * E-mail:
| | - Elodie Calvez
- Institut Pasteur de Nouvelle-Calédonie, URE Dengue et Arboviroses, Institut Pasteur International Network, Noumea, New Caledonia
| | - Catherine Inizan
- Institut Pasteur de Nouvelle-Calédonie, URE Dengue et Arboviroses, Institut Pasteur International Network, Noumea, New Caledonia
| | - Nicolas Pocquet
- Institut Pasteur de Nouvelle-Calédonie, URE Entomologie Médicale, Institut Pasteur International Network, Noumea, New Caledonia
| | - Vincent Richard
- Institut Pasteur de Nouvelle-Calédonie, Direction, Institut Pasteur International Network, Noumea, New Caledonia
| | - Myrielle Dupont-Rouzeyrol
- Institut Pasteur de Nouvelle-Calédonie, URE Dengue et Arboviroses, Institut Pasteur International Network, Noumea, New Caledonia
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Kamgang B, Vazeille M, Tedjou A, Yougang AP, Wilson-Bahun TA, Mousson L, Wondji CS, Failloux AB. Different populations of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) from Central Africa are susceptible to Zika virus infection. PLoS Negl Trop Dis 2020; 14:e0008163. [PMID: 32203510 PMCID: PMC7117767 DOI: 10.1371/journal.pntd.0008163] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 04/02/2020] [Accepted: 02/21/2020] [Indexed: 11/18/2022] Open
Abstract
Zika virus (ZIKV) is a Flavivirus (Flaviviridae) transmitted to humans mainly by the bite of an infected Aedes mosquitoes. Aedes aegypti is the primary epidemic vector of ZIKV and Ae. albopictus, the secondary one. However, the epidemiological role of both Aedes species in Central Africa where Ae. albopictus was recently introduced is poorly characterized. Field-collected strains of Ae. aegypti and Ae. albopictus from different ecological settings in Central Africa were experimentally infected with a ZIKV strain isolated in West Africa. Mosquitoes were analysed at 14- and 21-days post-exposure. Both Ae. aegypti and Ae. albopictus were able to transmit ZIKV but with higher overall transmission efficiency for Ae. aegypti (57.9%) compared to Ae. albopictus (41.5%). In addition, disseminated infection and transmission rates for both Ae. aegypti and Ae. albopictus varied significantly according to the location where they were sampled from. We conclude that both Ae. aegypti and Ae. albopictus are able to transmit ZIKV and may intervene as active Zika vectors in Central Africa. These findings could contribute to a better understanding of the epidemiological transmission of ZIKV in Central Africa and develop suitable strategy to prevent major ZIKV outbreaks in this region. Zika virus (ZIKV), isolated for the first time in Uganda in 1947, is transmitted to human beings mainly by the bite of an infected mosquitoes belonging to the Aedes genus notably Ae. aegypti and Ae. albopictus. Both Aedes species are present in Central Africa, however their epidemiological role is poorly characterized. Here, we assessed the ability of Ae. aegypti and Ae. albopictus collected in different ecological settings in Central Africa to transmit a ZIKV strain isolated in West Africa. Analysis showed that both Ae. aegypti and Ae. albopictus are able to transmit ZIKV but with higher overall transmission efficiency for Ae. aegypti compared to Ae. albopictus. In addition, disseminated infection and transmission rates for both Aedes species varied significantly according to the sampling location. Overall, our result suggests that in Central Africa, Ae. aegypti is more competent to transmit ZIKV than Ae. albopictus although parameters such as the feeding behaviour, longevity and mosquito densities can modulate pathogens transmission in nature. These findings could contribute to a better understanding of the epidemiological transmission of ZIKV in Central Africa and develop suitable strategy to prevent major ZIKV outbreaks in this region.
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Affiliation(s)
- Basile Kamgang
- Centre for Research in Infectious Diseases, Department of Medical Entomology, Yaoundé, Cameroon
- * E-mail: ,
| | - Marie Vazeille
- Institut Pasteur, Department of Virology, Unit of Arboviruses and Insect Vectors, Paris, France
| | - Armel Tedjou
- Centre for Research in Infectious Diseases, Department of Medical Entomology, Yaoundé, Cameroon
- Department of Animal Biology, Faculty of Sciences, University of Yaoundé I, Yaoundé, Cameroon
| | - Aurélie P. Yougang
- Centre for Research in Infectious Diseases, Department of Medical Entomology, Yaoundé, Cameroon
- Department of Animal Biology, Faculty of Sciences, University of Yaoundé I, Yaoundé, Cameroon
| | - Theodel A. Wilson-Bahun
- Centre for Research in Infectious Diseases, Department of Medical Entomology, Yaoundé, Cameroon
- Faculty of Science and Technology, Marien Ngouabi University, Brazzaville, Congo
| | - Laurence Mousson
- Institut Pasteur, Department of Virology, Unit of Arboviruses and Insect Vectors, Paris, France
| | - Charles S. Wondji
- Centre for Research in Infectious Diseases, Department of Medical Entomology, Yaoundé, Cameroon
- Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Anna-Bella Failloux
- Institut Pasteur, Department of Virology, Unit of Arboviruses and Insect Vectors, Paris, France
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