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Keven JB, Vinit R, Katusele M, Reimer LJ, Zimmerman PA, Karl S, Walker ED. Genetic differentiation and bottleneck effects in the malaria vectors Anopheles farauti and Anopheles punctulatus after an LLIN-based vector control program in Papua New Guinea. Ecol Evol 2024; 14:e10917. [PMID: 38371856 PMCID: PMC10869881 DOI: 10.1002/ece3.10917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 01/09/2024] [Accepted: 01/15/2024] [Indexed: 02/20/2024] Open
Abstract
Implementation of long-lasting insecticide-treated net (LLIN) programs to control human malaria transmission leads to substantial reductions in the abundance of Anopheles mosquitoes, but the impact on the population genetic structure of the malaria vectors is poorly known, nor has it been investigated in Papua New Guinea, where malaria is highly endemic and where several species of Anopheles have vector roles. Here, we applied Wright's F-statistic, analysis of molecular variance, Bayesian structure analysis, and discriminant analysis of principle components to microsatellite genotype data to analyze the population genetic structure of Anopheles farauti between and within the northern and southern lowland plains and of Anopheles punctulatus within the northern plain of Papua New Guinea after such a program. Bottleneck effects in the two malaria vectors were analyzed using Luikart and Cornuet's tests of heterozygosity. A large, panmictic population of An. punctulatus pre-LLIN program diverged into two subregional populations corresponding to Madang and East Sepik provinces post-LLIN distribution and experienced a genetic bottleneck during this process. By contrast, the An. farauti population existed as two regional populations isolated by mountain ranges pre-LLIN, a genetic structure that persisted after the distribution of LLINs with no further geographic differentiation nor evidence of a genetic bottleneck. These findings show the differential response of populations of different vector species to interventions, which has implications for program sustainability and gene flow.
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Affiliation(s)
- John B. Keven
- Department of Population Health and Disease Prevention, Program in Public HealthUniversity of California‐IrvineIrvineCaliforniaUSA
- Department of EntomologyMichigan State UniversityEast LansingMichiganUSA
- Department of Microbiology and Molecular GeneticsMichigan State UniversityEast LansingMichiganUSA
- Vector‐borne Diseases UnitPapua New Guinea Institute of Medical ResearchMadangMadang ProvincePapua New Guinea
| | - Rebecca Vinit
- Vector‐borne Diseases UnitPapua New Guinea Institute of Medical ResearchMadangMadang ProvincePapua New Guinea
| | - Michelle Katusele
- Vector‐borne Diseases UnitPapua New Guinea Institute of Medical ResearchMadangMadang ProvincePapua New Guinea
| | - Lisa J. Reimer
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Peter A. Zimmerman
- Center for Global Health and Diseases, Pathology DepartmentCase Western Reserve UniversityClevelandOhioUSA
| | - Stephan Karl
- Vector‐borne Diseases UnitPapua New Guinea Institute of Medical ResearchMadangMadang ProvincePapua New Guinea
- Australian Institute of Tropical Health and MedicineJames Cook UniversityCairnsQueenslandAustralia
| | - Edward D. Walker
- Department of EntomologyMichigan State UniversityEast LansingMichiganUSA
- Department of Microbiology and Molecular GeneticsMichigan State UniversityEast LansingMichiganUSA
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Mueller I, Vantaux A, Karl S, Laman M, Witkowski B, Pepey A, Vinit R, White M, Barry A, Beeson JG, Robinson LJ. Asia-Pacific ICEMR: Understanding Malaria Transmission to Accelerate Malaria Elimination in the Asia Pacific Region. Am J Trop Med Hyg 2022; 107:131-137. [PMID: 36228917 PMCID: PMC9662229 DOI: 10.4269/ajtmh.21-1336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Accepted: 07/06/2022] [Indexed: 01/31/2023] Open
Abstract
Gaining an in-depth understanding of malaria transmission requires integrated, multifaceted research approaches. The Asia-Pacific International Center of Excellence in Malaria Research (ICEMR) is applying specifically developed molecular and immunological assays, in-depth entomological assessments, and advanced statistical and mathematical modeling approaches to a rich series of longitudinal cohort and cross-sectional studies in Papua New Guinea and Cambodia. This is revealing both the essential contribution of forest-based transmission and the particular challenges posed by Plasmodium vivax to malaria elimination in Cambodia. In Papua New Guinea, these studies document the complex host-vector-parasite interactions that are underlying both the stunning reductions in malaria burden from 2006 to 2014 and the significant resurgence in transmission in 2016 to 2018. Here we describe the novel analytical, surveillance, molecular, and immunological tools that are being applied in our ongoing Asia-Pacific ICEMR research program.
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Affiliation(s)
- Ivo Mueller
- Population Health & Immunity Division, Walter + Eliza Hall Institutes, Melbourne, Australia;,University of Melbourne, Melbourne, Australia;,Address correspondence to Ivo Mueller, Population Health & Immunity Division, Walter + Eliza Hall Institutes, 1G Royal Parade, Parkville, Victoria, Australia 3052. E-mail:
| | | | - Stephan Karl
- Australian Institute of Tropical Health & Medicine, James Cook University, Cairns, Australia;,PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Moses Laman
- PNG Institute of Medical Research, Madang, Papua New Guinea
| | | | - Anais Pepey
- Institute Pasteur Cambodia, Phnom Penh, Cambodia
| | - Rebecca Vinit
- PNG Institute of Medical Research, Madang, Papua New Guinea
| | | | - Alyssa Barry
- Deakin University, Geelong, Australia;,Burnet Institute, Melbourne, Australia
| | - James G. Beeson
- University of Melbourne, Melbourne, Australia;,Burnet Institute, Melbourne, Australia;,Monash University, Victoria, Australia
| | - Leanne J. Robinson
- Population Health & Immunity Division, Walter + Eliza Hall Institutes, Melbourne, Australia;,PNG Institute of Medical Research, Madang, Papua New Guinea;,Burnet Institute, Melbourne, Australia;,Monash University, Victoria, Australia
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Goi J, Koinari M, Muker S, Vinit R, Pomat W, Williams DT, Karl S. Comparison of Different Mosquito Traps for Zoonotic Arbovirus Vectors in Papua New Guinea. Am J Trop Med Hyg 2022; 106:823-827. [PMID: 35026726 PMCID: PMC8922509 DOI: 10.4269/ajtmh.21-0640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 11/03/2021] [Indexed: 11/07/2022] Open
Abstract
Vector surveillance is important to control mosquito-borne diseases. We compared the efficacies of three mosquito-trapping devices: the CDC light trap with incandescent light (CDC_I), the CDC light trap with ultraviolet light (CDC_UV), and the Biogents-sentinel (BG) trap, to identify a suitable and cost-effective surveillance tool for key vectors of neglected zoonotic arboviral diseases in Papua New Guinea (PNG). Of 13,788 female mosquitoes, CDC_I caught 7.9%, BG caught 14.5%, and CDC_UV caught 77.6%. Culex was the most predominant genus caught in all the traps. Centers for Disease Control light trap with ultraviolet light trap captured the highest abundance, highest species richness of mosquitoes and exhibited the highest overall Culex mosquito capture rates compared with BG and CDC_l. This study represents the first assessment of trapping devices for zoonotic arbovirus vectors in PNG. We recommend the CDC _UV trap for future monitoring and surveillance of infectious arboviral vector programs in PNG.
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Affiliation(s)
- Joelyn Goi
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Melanie Koinari
- Australian Institute of Tropical Health and Medicine, James Cook University, Smithfield, Australia;,Address correspondence to Melanie Koinari, Australian Institute of Tropical Health and Medicine, James Cook University, 1/14-88 McGregor Rd., Smithfield, Queensland, Australia. E-mail:
| | - Sakur Muker
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Rebecca Vinit
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - William Pomat
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - David T. Williams
- CSIRO, Australian Centre for Disease Preparedness, Geelong, Australia
| | - Stephan Karl
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea;,Australian Institute of Tropical Health and Medicine, James Cook University, Smithfield, Australia
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Timinao L, Vinit R, Katusele M, Koleala T, Nate E, Czeher C, Burkot TR, Schofield L, Felger I, Mueller I, Laman M, Robinson LJ, Karl S. Infectivity of Symptomatic Malaria Patients to Anopheles farauti Colony Mosquitoes in Papua New Guinea. Front Cell Infect Microbiol 2022; 11:771233. [PMID: 35004348 PMCID: PMC8729879 DOI: 10.3389/fcimb.2021.771233] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/29/2021] [Indexed: 11/23/2022] Open
Abstract
Plasmodium transmission from humans to mosquitoes is an understudied bottleneck in the transmission of malaria. Direct membrane feeding assays (DMFA) allow detailed malaria transmission studies from humans to mosquitoes. Especially for Plasmodium vivax, which cannot be cultured long-term under laboratory conditions, implementation of DMFAs requires proximity to P. vivax endemic areas. In this study, we investigated the infectivity of symptomatic Plasmodium infections to Anopheles farauti colony mosquitoes in Papua New Guinea (PNG). A total of 182 DMFAs were performed with venous blood collected from rapid diagnostic test (RDT) positive symptomatic malaria patients and subsequently analysed by light microscopy and quantitative real time polymerase chain reaction (qPCR). DMFAs resulted in mosquito infections in 20.9% (38/182) of cases. By light microscopy and qPCR, 10 – 11% of P. falciparum and 32 – 44% of P. vivax positive individuals infected An. farauti. Fifty-eight percent of P. vivax and 15% of P. falciparum gametocytaemic infections infected An farauti.
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Affiliation(s)
- Lincoln Timinao
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.,Australian Institute of Tropical Health and Medicine, James Cook University, Smithfield, QLD, Australia
| | - Rebecca Vinit
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Michelle Katusele
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Tamarah Koleala
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Elma Nate
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Cyrille Czeher
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Thomas R Burkot
- Australian Institute of Tropical Health and Medicine, James Cook University, Smithfield, QLD, Australia
| | - Louis Schofield
- Australian Institute of Tropical Health and Medicine, James Cook University, Smithfield, QLD, Australia
| | - Ingrid Felger
- Molecular Diagnostics Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland.,Department Biozentrum, University of Basel, Basel, Switzerland
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia.,Malaria Parasites and Hosts Unit, Department of Parasites & Insect Vectors, Institut Pasteur, Paris, France
| | - Moses Laman
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Leanne J Robinson
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, Australia.,Vector-Borne Diseases and Tropical Public Health Division, Burnet Institute, Melbourne, VIC, Australia
| | - Stephan Karl
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.,Australian Institute of Tropical Health and Medicine, James Cook University, Smithfield, QLD, Australia
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Keven JB, Katusele M, Vinit R, Rodríguez-Rodríguez D, Hetzel MW, Robinson LJ, Laman M, Karl S, Walker ED. Vector composition, abundance, biting patterns and malaria transmission intensity in Madang, Papua New Guinea: assessment after 7 years of an LLIN-based malaria control programme. Malar J 2022; 21:7. [PMID: 34983530 PMCID: PMC8729043 DOI: 10.1186/s12936-021-04030-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 12/17/2021] [Indexed: 11/18/2022] Open
Abstract
Background A malaria control programme based on distribution of long-lasting insecticidal bed nets (LLINs) and artemisinin combination therapy began in Papua New Guinea in 2009. After implementation of the programme, substantial reductions in vector abundance and malaria transmission intensity occurred. The research reported here investigated whether these reductions remained after seven years of sustained effort. Methods All-night (18:00 to 06:00) mosquito collections were conducted using human landing catches and barrier screen methods in four villages of Madang Province between September 2016 and March 2017. Anopheles species identification and sporozoite infection with Plasmodium vivax and Plasmodium falciparum were determined with molecular methods. Vector composition was expressed as the relative proportion of different species in villages, and vector abundance was quantified as the number of mosquitoes per barrier screen-night and per person-night. Transmission intensity was quantified as the number of sporozoite-infective vector bites per person-night. Results Five Anopheles species were present, but vector composition varied greatly among villages. Anopheles koliensis, a strongly anthropophilic species was the most prevalent in Bulal, Matukar and Wasab villages, constituting 63.7–73.8% of all Anopheles, but in Megiar Anopheles farauti was the most prevalent species (97.6%). Vector abundance varied among villages (ranging from 2.8 to 72.3 Anopheles per screen-night and 2.2–31.1 Anopheles per person-night), and spatially within villages. Malaria transmission intensity varied among the villages, with values ranging from 0.03 to 0.5 infective Anopheles bites per person-night. Most (54.1–75.1%) of the Anopheles bites occurred outdoors, with a substantial proportion (25.5–50.8%) occurring before 22:00. Conclusion The estimates of vector abundance and transmission intensity in the current study were comparable to or higher than estimates in the same villages in 2010–2012, indicating impeded programme effectiveness. Outdoor and early biting behaviours of vectors are some of the likely explanatory factors. Heterogeneity in vector composition, abundance and distribution among and within villages challenge malaria control programmes and must be considered when planning them. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-04030-4.
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Affiliation(s)
- John B Keven
- Department of Entomology, Michigan State University, East Lansing, MI, USA. .,Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA. .,Papua New Guinea Institute of Medical Research, Vector-Borne Diseases Unit, Madang, Papua New Guinea.
| | - Michelle Katusele
- Papua New Guinea Institute of Medical Research, Vector-Borne Diseases Unit, Madang, Papua New Guinea
| | - Rebecca Vinit
- Papua New Guinea Institute of Medical Research, Vector-Borne Diseases Unit, Madang, Papua New Guinea
| | | | - Manuel W Hetzel
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Leanne J Robinson
- Papua New Guinea Institute of Medical Research, Vector-Borne Diseases Unit, Madang, Papua New Guinea.,Burnet Institute, Melbourne, VIC, Australia.,Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Moses Laman
- Papua New Guinea Institute of Medical Research, Vector-Borne Diseases Unit, Madang, Papua New Guinea
| | - Stephan Karl
- Papua New Guinea Institute of Medical Research, Vector-Borne Diseases Unit, Madang, Papua New Guinea.,Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
| | - Edward D Walker
- Department of Entomology, Michigan State University, East Lansing, MI, USA.,Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
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Keven JB, Katusele M, Vinit R, Rodríguez-Rodríguez D, Hetzel MW, Robinson LJ, Laman M, Karl S, Foran DR, Walker ED. Nonrandom Selection and Multiple Blood Feeding of Human Hosts by Anopheles Vectors: Implications for Malaria Transmission in Papua New Guinea. Am J Trop Med Hyg 2021; 105:1747-1758. [PMID: 34583342 PMCID: PMC8641310 DOI: 10.4269/ajtmh.21-0210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 07/21/2021] [Indexed: 11/07/2022] Open
Abstract
Nonrandom selection and multiple blood feeding of human hosts by Anopheles mosquitoes may exacerbate malaria transmission. Both patterns of blood feeding and their relationship to malaria epidemiology were investigated in Anopheles vectors in Papua New Guinea (PNG). Blood samples from humans and mosquito blood meals were collected in villages and human genetic profiles ("fingerprints") were analyzed by genotyping 23 microsatellites and a sex-specific marker. Frequency of blood meals acquired from different humans, identified by unique genetic profiles, was fitted to Poisson and negative binomial distributions to test for nonrandom patterns of host selection. Blood meals with more than one genetic profiles were classified as mosquitoes that fed on multiple humans. The age of a person bitten by a mosquito was determined by matching the blood-meal genetic profile to the villagers' genetic profiles. Malaria infection in humans was determined by PCR test of blood samples. The results show nonrandom distribution of blood feeding among humans, with biased selection toward males and individuals aged 15-30 years. Prevalence of Plasmodium falciparum infection was higher in this age group, suggesting males in this age range could be super-spreaders of malaria parasites. The proportion of mosquitoes that fed on multiple humans ranged from 6% to 13% among villages. The patterns of host utilization observed here can amplify transmission and contribute to the persistence of malaria in PNG despite efforts to suppress it with insecticidal bed nets. Excessive feeding on males aged 15-30 years underscores the importance of targeted interventions focusing on this demographic group.
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Affiliation(s)
- John B. Keven
- Department of Microbiology and Molecular Genetics, and Department of Entomology, Michigan State University, East Lansing, Michigan
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Michelle Katusele
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Rebecca Vinit
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Daniela Rodríguez-Rodríguez
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- Department of Epidemiology and Public Health, University of Basel, Basel, Switzerland
| | - Manuel W. Hetzel
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- Department of Epidemiology and Public Health, University of Basel, Basel, Switzerland
| | - Leanne J. Robinson
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
- Vector-Borne Diseases and Tropical Public Health Group, Burnet Institute, Melbourne, Victoria, Australia
- Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Moses Laman
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Stephan Karl
- Vector-borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
| | - David R. Foran
- School of Criminal Justice and Department of Integrative Biology, Michigan State University, Michigan
| | - Edward D. Walker
- Department of Microbiology and Molecular Genetics, and Department of Entomology, Michigan State University, East Lansing, Michigan
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Demok S, Endersby-Harshman N, Vinit R, Timinao L, Robinson LJ, Susapu M, Makita L, Laman M, Hoffmann A, Karl S. Insecticide resistance status of Aedes aegypti and Aedes albopictus mosquitoes in Papua New Guinea. Parasit Vectors 2019; 12:333. [PMID: 31269965 PMCID: PMC6609403 DOI: 10.1186/s13071-019-3585-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 06/27/2019] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Aedes aegypti and Ae. albopictus are important vectors of infectious diseases, especially those caused by arboviruses such as dengue, chikungunya and Zika. Aedes aegypti is very well adapted to urban environments, whereas Ae. albopictus inhabits more rural settings. Pyrethroid resistance is widespread in these vectors, but limited data exist from the Southwest Pacific Region, especially from Melanesia. While Aedes vector ecology is well documented in Australia, where incursion of Ae. albopictus and pyrethroid resistance have so far been prevented, almost nothing is known about Aedes populations in neighbouring Papua New Guinea (PNG). With pyrethroid resistance documented in parts of Indonesia but not in Australia, it is important to determine the distribution of susceptible and resistant Aedes populations in this region. METHODS The present study was aimed at assessing Aedes populations for insecticide resistance in Madang and Port Moresby, located on the north and south coasts of PNG, respectively. Mosquitoes were collected using ovitraps and reared in an insectary. Standard WHO bioassays using insecticide-treated filter papers were conducted on a total of 253 Ae. aegypti and 768 Ae. albopictus adult mosquitoes. Subsets of samples from both species (55 Ae. aegypti and 48 Ae. albopictus) were screened for knockdown resistance mutations in the voltage-sensitive sodium channel (Vssc) gene, the target site of pyrethroid insecticides. RESULTS High levels of resistance against pyrethroids were identified in Ae. aegypti from Madang and Port Moresby. Aedes albopictus exhibited susceptibility to pyrethroids, but moderate levels of resistance to DDT. Mutations associated with pyrethroid resistance were detected in all Ae. aegypti samples screened. Some genotypes found in the present study had been observed previously in Indonesia. No Vssc mutations associated with pyrethroid resistance were found in the Ae. albopictus samples. CONCLUSIONS To our knowledge, this is the first report of pyrethroid resistance in Ae. aegypti mosquitoes in PNG. Interestingly, usage of insecticides in PNG is low, apart from long-lasting insecticidal nets distributed for malaria control. Further investigations on how these resistant Ae. aegypti mosquito populations arose in PNG and how they are being sustained are warranted.
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Affiliation(s)
- Samuel Demok
- Vector-Borne Diseases Unit, PNG Institute of Medical Research, P.O. Box 378, Madang, 511 Madang Province Papua New Guinea
| | - Nancy Endersby-Harshman
- School of BioSciences, Bio21 Institute, The University of Melbourne, 30 Flemington Rd., Parkville, VIC 3010 Australia
| | - Rebecca Vinit
- Vector-Borne Diseases Unit, PNG Institute of Medical Research, P.O. Box 378, Madang, 511 Madang Province Papua New Guinea
| | - Lincoln Timinao
- Vector-Borne Diseases Unit, PNG Institute of Medical Research, P.O. Box 378, Madang, 511 Madang Province Papua New Guinea
- Australian Institute of Tropical Health and Medicine, James Cook University, 1/14-88 McGregor Road, Smithfield, QLD 4870 Australia
| | - Leanne J. Robinson
- Vector-Borne Diseases Unit, PNG Institute of Medical Research, P.O. Box 378, Madang, 511 Madang Province Papua New Guinea
- Burnet Institute, 85 Commercial Road, Melbourne, VIC 3004 Australia
| | - Melinda Susapu
- National Department of Health, Waigani Drive, P.O. Box 807, Port Moresby, Papua New Guinea
| | - Leo Makita
- National Department of Health, Waigani Drive, P.O. Box 807, Port Moresby, Papua New Guinea
| | - Moses Laman
- Vector-Borne Diseases Unit, PNG Institute of Medical Research, P.O. Box 378, Madang, 511 Madang Province Papua New Guinea
| | - Ary Hoffmann
- School of BioSciences, Bio21 Institute, The University of Melbourne, 30 Flemington Rd., Parkville, VIC 3010 Australia
| | - Stephan Karl
- Vector-Borne Diseases Unit, PNG Institute of Medical Research, P.O. Box 378, Madang, 511 Madang Province Papua New Guinea
- Australian Institute of Tropical Health and Medicine, James Cook University, 1/14-88 McGregor Road, Smithfield, QLD 4870 Australia
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Keven JB, Katusele M, Vinit R, Koimbu G, Vincent N, Thomsen EK, Karl S, Reimer LJ, Walker ED. Species abundance, composition, and nocturnal activity of female Anopheles (Diptera: Culicidae) in malaria-endemic villages of Papua New Guinea: assessment with barrier screen sampling. Malar J 2019; 18:96. [PMID: 30909928 PMCID: PMC6434780 DOI: 10.1186/s12936-019-2742-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 03/21/2019] [Indexed: 11/18/2022] Open
Abstract
Background Community composition of Anopheles mosquitoes, and their host-seeking and peridomestic behaviour, are important factors affecting malaria transmission. In this study, barrier screen sampling was used to investigate species composition, abundance, and nocturnal activity of Anopheles populations in villages of Papua New Guinea. Methods Mosquitoes were sampled from 6 pm to 6 am in five villages from 2012 to 2016. The barrier screens were positioned between the village houses and the perimeter of villages where cultivated and wild vegetation (“the bush”) grew thickly. Female Anopheles that rested on either village or bush side of the barrier screens, as they commuted into and out of the villages, were captured. Similarity in species composition among villages was assessed. Mosquitoes captured on village and bush sides of the barrier screens were sorted by feeding status and by hour of collection, and their numbers were compared using negative binomial generalized linear models. Results Females of seven Anopheles species were present in the sample. Species richness ranged from four to six species per village, but relative abundance was highly uneven within and between villages, and community composition was similar for two pairs of villages and highly dissimilar in a fifth. For most Anopheles populations, more unfed than blood-fed mosquitoes were collected from the barrier screens. More blood-fed mosquitoes were found on the side of the barrier screens facing the village and relatively more unfed ones on the bush side, suggesting commuting behaviour of unfed host-seeking females into the villages from nearby bush and commuting of blood-fed females away from villages towards the bush. For most populations, the majority of host-seeking mosquitoes arrived in the village before midnight when people were active and unprotected from the mosquitoes by bed nets. Conclusion The uneven distribution of Anopheles species among villages, with each site dominated by different species, even among nearby villages, emphasizes the importance of vector heterogeneity in local malaria transmission and control. Yet, for most species, nocturnal activity patterns of village entry and host seeking predominantly occurred before midnight indicating common behaviours across species and populations relative to human risk of exposure to Anopheles bites. Electronic supplementary material The online version of this article (10.1186/s12936-019-2742-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- John B Keven
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea. .,Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA.
| | - Michelle Katusele
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Rebecca Vinit
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Gussy Koimbu
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Naomi Vincent
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | | | - Stephan Karl
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea.,Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, Melbourne University, Parkville, VIC, Australia
| | - Lisa J Reimer
- Liverpool School of Tropical Medicine, Liverpool, UK
| | - Edward D Walker
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
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Keven JB, Reimer L, Katusele M, Koimbu G, Vinit R, Vincent N, Thomsen E, Foran DR, Zimmerman PA, Walker ED. Plasticity of host selection by malaria vectors of Papua New Guinea. Parasit Vectors 2017; 10:95. [PMID: 28222769 PMCID: PMC5320767 DOI: 10.1186/s13071-017-2038-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 02/15/2017] [Indexed: 11/20/2022] Open
Abstract
Background Host selection is an important determinant of vectorial capacity because malaria transmission increases when mosquitoes feed more on humans than non-humans. Host selection also affects the outcome of long-lasting insecticidal nets (LLIN). Despite the recent nationwide implementation of LLIN-based malaria control program in Papua New Guinea (PNG), little is known about the host selection of the local Anopheles vectors. This study investigated the host selection of Anopheles vectors in PNG. Methods Blood-engorged mosquitoes were sampled using the barrier screen method and blood meals analyzed for vertebrate host source with PCR-amplification of the mitochondrial cytochrome b gene. Abundance of common hosts was estimated in surveys. The test of homogeneity of proportions and the Manly resource selection ratio were used to determine if hosts were selected in proportion to their abundance. Results Two thousand four hundred and forty blood fed Anopheles females of seven species were sampled from five villages in Madang, PNG. Of 2,142 samples tested, 2,061 (96.2%) yielded a definitive host source; all were human, pig, or dog. Hosts were not selected in proportion to their abundance, but rather were under-selected or over-selected by the mosquitoes. Four species, Anopheles farauti (sensu stricto) (s.s.), Anopheles punctulatus (s.s.), Anopheles farauti no. 4 and Anopheles longirostris, over-selected humans in villages with low LLIN usage, but over-selected pigs in villages with high LLIN usage. Anopheles koliensis consistently over-selected humans despite high LLIN usage, and Anopheles bancroftii over-selected pigs. Conclusions The plasticity of host selection of an Anopheles species depends on its opportunistic, anthropophilic or zoophilic behavior, and on the extent of host availability and LLIN usage where the mosquitoes forage for hosts. The high anthropophily of An. koliensis increases the likelihood of contacting the LLIN inside houses. This allows its population size to be reduced to levels insufficient to support transmission. In contrast, by feeding on alternative hosts the likelihood of the opportunistic species to contact LLIN is lower, making them difficult to control. By maintaining high population size, the proportion that feed on humans outdoors can sustain residual transmission despite high LLIN usage in the village. Electronic supplementary material The online version of this article (doi:10.1186/s13071-017-2038-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- John B Keven
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, 511, Madang, Papua New Guinea. .,Department of Microbiology and Molecular Genetics, Michigan State University, 48824, East Lansing, MI, USA.
| | - Lisa Reimer
- Liverpool School of Tropical Medicine and Hygiene, Liverpool, UK
| | - Michelle Katusele
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, 511, Madang, Papua New Guinea
| | - Gussy Koimbu
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, 511, Madang, Papua New Guinea
| | - Rebecca Vinit
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, 511, Madang, Papua New Guinea.,Department of Entomology, Michigan State University, 48824, East Lansing, MI, USA
| | - Naomi Vincent
- Papua New Guinea Institute of Medical Research, Vector Borne Diseases Unit, Madang, 511, Madang, Papua New Guinea
| | - Edward Thomsen
- Liverpool School of Tropical Medicine and Hygiene, Liverpool, UK
| | - David R Foran
- School of Criminal Justice and Department of Integrative Biology, Michigan State University, 48824, East Lansing, MI, USA
| | - Peter A Zimmerman
- Center for Global Health and Diseases, Case Western Reserve University, 44106, Cleveland, OH, USA
| | - Edward D Walker
- Department of Microbiology and Molecular Genetics, Michigan State University, 48824, East Lansing, MI, USA.,Department of Entomology, Michigan State University, 48824, East Lansing, MI, USA
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Shalini C, Kumar P, A. Singh K, Vinit R, Amit R, K. Amit K, Prakash A, Saha S. Protective Effect of Naringin against Pylorus Ligation-induced Esophagitis in Male Wistar Rats. Indian J Pharm Sci 2017. [DOI: 10.4172/pharmaceutical-sciences.1000223] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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