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Atencia–Pineda MC, Diaz-Ortiz D, Pareja–Loaiza P, García–Leal J, Hoyos–López R, Calderón–Rangel A, Fragozo-Castilla P, Pacheco-Lugo L, Flores AE, Maestre–Serrano R. Assessing pyrethroid resistance in Aedes aegypti from Cordoba Colombia: Implications of kdr mutations. PLoS One 2024; 19:e0309201. [PMID: 39172980 PMCID: PMC11340990 DOI: 10.1371/journal.pone.0309201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Accepted: 08/08/2024] [Indexed: 08/24/2024] Open
Abstract
Resistance to insecticides is one of the great challenges that vector control programs must face. The constant use of pyrethroid-type insecticides worldwide has caused selection pressure in populations of the Aedes aegypti vector, which has promoted the emergence of resistant populations. The resistance mechanism to pyrethroid insecticides most studied to date is target-site mutations that desensitize the voltage-gated sodium channel (VGSC) of the insect to the action of pyrethroids. In the present study, susceptibility to the pyrethroid insecticides permethrin, lambda-cyhalothrin, and deltamethrin was evaluated in fourteen populations from the department of Córdoba, Colombia. The CDC bottle bioassay and WHO tube methods were used. Additionally, the frequencies of the F1534C, V1016I, and V410L mutations were determined, and the association of resistance with the tri-locus haplotypes was examined. The results varied between the two techniques used, with resistance to permethrin observed in thirteen of the fourteen populations, resistance to lambda-cyhalothrin in two populations, and susceptibility to deltamethrin in all the populations under study with the CDC method. In contrast, the WHO method showed resistance to the three insecticides evaluated in all populations. The frequencies of the mutated alleles ranged from 0.05-0.43 for 1016I, 0.94-1.0 for 1534C, and 0.01-0.59 for 410L. The triple homozygous mutant CIL haplotype was associated with resistance to all three pyrethroids evaluated with the WHO bioassay, while with the CDC bioassay, it was only associated with resistance to permethrin. This study highlights the importance of implementing systematic monitoring of kdr mutations, allowing resistance management strategies to be dynamically adjusted to achieve effective control of Aedes aegypti.
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Affiliation(s)
- María Claudia Atencia–Pineda
- Doctorado en Microbiología y Salud Tropical, Facultad de Medicina Veterinaria y Zootecnia, Universidad de Córdoba, Montería, Colombia
| | - Diana Diaz-Ortiz
- Facultad de Ciencias Básicas y Biomédicas, Centro de Investigación en Ciencias de la Vida (CICV), Universidad Simón Bolívar, Barranquilla, Colombia
| | - Paula Pareja–Loaiza
- Facultad de Ciencias de la Salud, Centro de Investigación en Ciencias de la Vida (CICV), Universidad Simón Bolívar, Barranquilla, Colombia
| | - Javier García–Leal
- Facultad de Ciencias Básicas y Biomédicas, Centro de Investigación en Ciencias de la Vida (CICV), Universidad Simón Bolívar, Barranquilla, Colombia
| | - Richard Hoyos–López
- Instituto de Investigaciones Biológicas del Trópico (IIBT), Universidad de Córdoba, Montería, Colombia
| | - Alfonso Calderón–Rangel
- Instituto de Investigaciones Biológicas del Trópico (IIBT), Universidad de Córdoba, Montería, Colombia
| | - Pedro Fragozo-Castilla
- Grupo de Investigación Parasitología Agroecología Milenio, Universidad Popular del Cesar, Valledupar, Colombia
| | - Lisandro Pacheco-Lugo
- Facultad de Ciencias Básicas y Biomédicas, Centro de Investigación en Ciencias de la Vida (CICV), Universidad Simón Bolívar, Barranquilla, Colombia
| | - Adriana E. Flores
- Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garzas, México
| | - Ronald Maestre–Serrano
- Facultad de Ciencias de la Salud, Centro de Investigación en Ciencias de la Vida (CICV), Universidad Simón Bolívar, Barranquilla, Colombia
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Saeung M, Ngoen-Klan R, Yan C, Kerdsawang J, Nararak J, Manguin S, Hii J, Chareonviriyaphap T. Effects of mosquito age and batch size on knockdown and mortality of laboratory-reared Anopheles dirus, Anopheles minimus, and wild-caught Anopheles harrisoni (Diptera: Culicidae) exposed to transfluthrin using WHO tube and CDC bottle bioassays. JOURNAL OF MEDICAL ENTOMOLOGY 2024; 61:427-441. [PMID: 38284470 DOI: 10.1093/jme/tjae004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 11/10/2023] [Accepted: 01/12/2024] [Indexed: 01/30/2024]
Abstract
WHO tube and CDC bottle bioassays are currently available for insecticide resistance monitoring and malaria transmission research. Multiple parameters including mosquito density, age, and nutritional status may affect the readout in these bioassays' tests. This study aims to assess the effects of experimental factors on knockdown and mortality measurements in dominant malaria vectors in Thailand following exposure to sublethal and lethal doses of transfluthrin. The effects of (i) 3 different mosquito batch sizes (5, 10, and 20 individuals) and (ii) 2 age groups (3-5 and 20-23 days old) on outcomes measured using the WHO tube (14.7 µg/cm2) and CDC bottle bioassay discriminating concentration (0.006 µg/cm2) against 2 laboratory strains: Anopheles dirus Peyton & Harrison and Anopheles minimus Theobald (species A) and wild-caught Anopheles harrisoni Harbach & Manguin (species C). Our results showed higher knockdown at 1-h exposure using WHO tube and CDC bottle bioassays containing 20 individuals compared to batches containing 10 and 5 individuals. Older mosquitoes showed greater susceptibility than younger test population, especially for An. mininus. Our study supports WHO recommendations for using 3- to 5-day-old mosquitoes. It also validates Praulin et al. (2022) proposal to divide the cohort into smaller batches with more test replicates when it is not practicable to test 25 mosquitoes per replicate.
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Affiliation(s)
- Manop Saeung
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
- HSM, Univ. Montpellier, CNRS, IRD, Montpellier, France
| | - Ratchadawan Ngoen-Klan
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| | - Chanly Yan
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| | - Jutamas Kerdsawang
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| | - Jirod Nararak
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| | - Sylvie Manguin
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
- HSM, Univ. Montpellier, CNRS, IRD, Montpellier, France
| | - Jeffrey Hii
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
- College of Public Health, Medical and Veterinary Sciences, James Cook University, North Queensland, Australia
| | - Theeraphap Chareonviriyaphap
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
- Royal Society of Thailand, Bangkok, Thailand
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Odjo EM, Impoinvil D, Fassinou AJYH, Padonou GG, Aïkpon R, Salako AS, Sominahouin AA, Adoha C, Yovogan B, Osse R, Oussou O, Tokponnon F, Gnanguénon V, Hassani AS, Akogbeto MC. The frequency of kdr and ace-1 alleles in Anopheles gambiae s.l. before and during indoor residual spraying (IRS) implementation and four years after IRS withdrawal in three districts in Atacora, Benin. Parasit Vectors 2024; 17:115. [PMID: 38454494 PMCID: PMC10918995 DOI: 10.1186/s13071-024-06206-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 02/18/2024] [Indexed: 03/09/2024] Open
Abstract
BACKGROUND Indoor residual spraying (IRS) was first implemented in the Atacora department, Benin from 2011 to 2012 using bendiocarb (carbamate) followed by annual spraying with pirimiphos-methyl (organophosphate) from 2013 to 2018. Before and after IRS implementation in Atacora, standard pyrethroid insecticide-treated bed nets were the main method of vector control in the area. This study investigated the knockdown resistance (kdr) gene (L1014F) and the acetylcholinesterase (ace-1) gene (G119S), before and during IRS implementation, and 4-years after IRS withdrawal from Atacora. This was done to assess how changes in insecticide pressure from indoor residual spraying may have altered the genotypic resistance profile of Anopheles gambiae s.l. METHOD Identification of sibling species of An. gambiae s.l. and detection of the L1014F mutation in the kdr gene and G119S mutation in ace-1 genes was done using molecular analysis. Allelic and genotypic frequencies were calculated and compared with each other before and during IRS implementation and 4 years after IRS withdrawal. The Hardy-Weinberg equilibrium and genetic differentiation within and between populations were assessed. RESULTS Prevalence of the L1014F mutation in all geographic An. gambiae s.l. (An. gambiae s.s., Anopheles. coluzzii, Anopheles. arabiensis, and hybrids of "An. gambiae s.s. and An. coluzzii") populations increased from 69% before IRS to 87% and 90% during and after IRS. The G119S allele frequency during IRS (20%) was significantly higher than before IRS implementation (2%). Four years after IRS withdrawal, allele frequencies returned to similar levels as before IRS (3%). Four years after IRS withdrawal, the populations showed excess heterozygosity at the ace-1 gene and deficit heterozygosity at the kdr gene, whereas both genes had excess heterozygosity before and during IRS (FIS < 0). No genetic differentiation was observed within the populations. CONCLUSIONS This study shows that the withdrawal of IRS with bendiocarb and pirimiphos-methyl may have slowed down the selection of individual mosquitoes with ace-1 resistance alleles in contrast to populations of An. gambiae s.l. with the L1014F resistance allele of the kdr gene. This may suggest that withdrawing the use of carbamates or organophosphates from IRS or rotating alternative insecticides with different modes of action may slow the development of ace-1 insecticide-resistance mutations. The increase in the prevalence of the L1014F mutation of the kdr gene in the population, despite the cessation of IRS, could be explained by the growing use of pyrethroids and DDT in agriculture and for other domestic use. More observational studies in countries where carbamates or organophosphates are still being used as public health insecticides may provide additional insights into these associations.
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Affiliation(s)
- Esdras Mahoutin Odjo
- Centre de Recherche Entomologique de Cotonou, Cotonou, Bénin.
- Faculté des Sciences et Techniques-Université d'Abomey-Calavi, Abomey Calavi, Bénin.
| | - Daniel Impoinvil
- U.S. President's Malaria Initiative (PMI), U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA
| | | | - Gil Germain Padonou
- Centre de Recherche Entomologique de Cotonou, Cotonou, Bénin
- Faculté des Sciences et Techniques-Université d'Abomey-Calavi, Abomey Calavi, Bénin
| | - Rock Aïkpon
- Centre de Recherche Entomologique de Cotonou, Cotonou, Bénin
- Ecole Normale Supérieure de Natitingou, Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM) d'Abomey, Abomey, Bénin
| | | | | | - Constantin Adoha
- Centre de Recherche Entomologique de Cotonou, Cotonou, Bénin
- Faculté des Sciences et Techniques-Université d'Abomey-Calavi, Abomey Calavi, Bénin
| | - Boulais Yovogan
- Centre de Recherche Entomologique de Cotonou, Cotonou, Bénin
- Faculté des Sciences et Techniques-Université d'Abomey-Calavi, Abomey Calavi, Bénin
| | - Razaki Osse
- Centre de Recherche Entomologique de Cotonou, Cotonou, Bénin
- Université Nationale d'Agriculture de Porto-Novo, Porto-Novo, Bénin
| | - Olivier Oussou
- Centre de Recherche Entomologique de Cotonou, Cotonou, Bénin
| | | | - Virgile Gnanguénon
- US President's Malaria Initiative (PMI), U.S. Agency for International Development (USAID), Cotonou, Benin
| | - Ahmed Saadani Hassani
- US President's Malaria Initiative (PMI), U.S. Centers for Disease Control and Prevention (CDC), Cotonou, Benin
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Chaubey R, Shukla A, Kushwaha AK, Tiwary P, Kumar Singh S, Hennings S, Singh OP, Lawyer P, Rowton E, Petersen CA, Bernhardt SA, Sundar S. Assessing insecticide susceptibility, diagnostic dose and time for the sand fly Phlebotomus argentipes, the vector of visceral leishmaniasis in India, using the CDC bottle bioassay. PLoS Negl Trop Dis 2023; 17:e0011276. [PMID: 37163529 DOI: 10.1371/journal.pntd.0011276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 05/22/2023] [Accepted: 03/31/2023] [Indexed: 05/12/2023] Open
Abstract
Visceral leishmaniasis (VL) is a vector-borne protozoan disease, which can be fatal if left untreated. Synthetic chemical insecticides are very effective tools for controlling of insect vectors, including the sand fly Phlebotomus argentipes, the vector of VL in the Indian subcontinent. However, repeated use of the same insecticide with increasing doses potentially can create high selection pressure and lead to tolerance and resistance development. The objective of this study was to determine the lethal concentrations and assess levels of susceptibility, diagnostic doses and times to death of laboratory-reared P. argentipes to five insecticides that are used worldwide to control vectors. Using the Center for Disease Control and Prevention (CDC) bottle bioassay, 20-30 sand flies were exposed in insecticide- coated 500-ml glass bottles. Flies were then observed for 24 hours and mortality was recorded. Dose-response survival curves were generated for each insecticide using QCal software and lethal concentrations causing 50%, 90% and 95% mortality were determined. A bioassay was also conducted to determine diagnostic doses and diagnostic times by exposing 20-30 flies in each bottle containing set concentrations of insecticide. Mortality was recorded at 10-minute intervals for 120 minutes to generate the survival curve. Phlebotomus argentipes are highly susceptible to alpha-cypermethrin, followed by deltamethrin, malathion, chlorpyrifos, and least susceptible to DDT. Also, the lowest diagnostic doses and diagnostic times were established for alpha-cypermethrin (3μg/ml for 40 minutes) to kill 100% of the flies. The susceptibility data, diagnostic doses and diagnostic times presented here will be useful as baseline reference points for future studies to assess insecticide susceptibility and resistance monitoring of field caught sand flies and to assist in surveillance as VL elimination is achieved in the region.
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Affiliation(s)
- Rahul Chaubey
- Kala-Azar Medical Research Center, Muzaffarpur, Bihar, India
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Ashish Shukla
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Anurag Kumar Kushwaha
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Puja Tiwary
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | | | - Shawna Hennings
- Department of Biology, Utah State University, Logan, Utah, United States of America
| | - Om Praksh Singh
- Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Phillip Lawyer
- Arthropod Collections, Monte L. Bean Life Science Museum, Brigham Young University, Provo, Utah, United States of America
| | - Edgar Rowton
- Division of Entomology, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Christine A Petersen
- Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, Iowa, United States of America
- Center for Emerging Infectious Diseases, University of Iowa, Coralville, Iowa, United States of America
| | - Scott A Bernhardt
- Department of Biology, Utah State University, Logan, Utah, United States of America
| | - Shyam Sundar
- Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
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Wang Y, An M, Stevens KM, Liu N. Insecticide Resistance in Alabama Populations of the Mosquito Aedes albopictus. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:1678-1686. [PMID: 35851609 DOI: 10.1093/jme/tjac085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Indexed: 06/15/2023]
Abstract
The insecticide sensitivity and resistance status of both adults and larvae from six Aedes albopictus samples collected in Tuskegee, Tuscaloosa, Birmingham, Dothan, Mobile, and Montgomery, Alabama, were evaluated for the levels of sensitivity and resistance to eight insecticides: β-cyfluthrin, chlorpyrifos, deltamethrin, etofenprox, fenitrothion, permethrin, resmethrin, and malathion. Adult Ae. albopictus from all locations showed similar results for the difference between the time to 100% mortality and the diagnostic time in the CDC bottle bioassay, although Ae. albopictus survive longer than the diagnostic time to permethrin, fenitrothion, and resmethrin treatments. The larval bioassay indicated that malathion was the least toxic to Ae. albopictus from all locations (LC50: ranging from 0.1 ppm to 1.2 ppm), followed by resmethrin and etofenprox (LC50: 0.05 ppm-0.4 ppm), and deltamethrin and fenitrothion (LC50: 0.01 ppm-0.06 ppm). Chlorpyrifos exhibited the highest larval toxicity (LC50: 0.003 ppm-0.05 ppm). The resistance status of Ae. albopictus from all six locations was similar to the resistance levels found in a previous survey in 2004, indicating that in Alabama the development of resistance is slow in this strain, although comparing the resistance of Ae. albopictus from Tuskegee to that of a susceptible strain showed that it is resistant to chlorpyrifos. The slopes of the dose-response curves to most of the insecticides tested for these field populations of Ae. albopictus were generally similar to or slightly higher than those measured eighteen years previously, indicating that these populations are relatively homozygous in response to all the insecticides tested.
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Affiliation(s)
- Yifan Wang
- Department of Entomology and Plant Pathology, School of Agriculture, Auburn University, Auburn, AL 36849, USA
| | - Mengru An
- Department of Entomology and Plant Pathology, School of Agriculture, Auburn University, Auburn, AL 36849, USA
| | - Kelly M Stevens
- Alabama Department of Public Health, Montgomery, AL 36104, USA
| | - Nannan Liu
- Department of Entomology and Plant Pathology, School of Agriculture, Auburn University, Auburn, AL 36849, USA
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Hernandez HM, Martinez FA, Vitek CJ. Insecticide Resistance in Aedes aegypti Varies Seasonally and Geographically in Texas/Mexico Border Cities. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2022; 38:59-69. [PMID: 35276730 DOI: 10.2987/21-21-7034] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Insecticide use is the primary method of attempting to reduce or control the spread of mosquito-borne diseases. Insecticide resistance is a major concern as resistance will limit the efficacy of vector-control efforts. The lower Rio Grande Valley region of South Texas has had autochthonous transmission of multiple mosquito-borne diseases including those caused by dengue virus, chikungunya virus, and Zika virus. However, the current status of mosquito resistance to commonly used pesticides in this region is unknown. In this study, we collected field samples from multiple municipalities in South Texas and assessed resistance using the Centers for Disease Control and Prevention bottle bioassay. All populations exhibited characteristics of resistance, and permethrin was the most effective insecticide with an average mortality rate of 44.78%. Deltamethrin and sumethrin had significantly lower mortality rates of 20.31% and 32.16%, respectively, although neither of these insecticides are commonly used for vector-control activities in this region. Depending on which insecticide was used, there was little significance between each of the 7 cities. Seasonal variation in resistance was observed among the collection sites. Both deltamethrin and sumethrin exhibited an increase in susceptibility over the course of 10 months, while permethrin exhibited a decrease in susceptibility. These data highlight the need for further studies to determine if variations in resistance observed are repeated. The data and future findings may be useful in determining the most effective strategies for pesticide use and rotation.
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Affiliation(s)
- Heather M Hernandez
- University of Texas Rio Grande Valley, Center for Vector-Borne Diseases, 1201 W University Drive, Edinburg, Texas 78539
| | - Flor A Martinez
- University of Texas Rio Grande Valley, Center for Vector-Borne Diseases, 1201 W University Drive, Edinburg, Texas 78539
| | - Christopher J Vitek
- University of Texas Rio Grande Valley, Center for Vector-Borne Diseases, 1201 W University Drive, Edinburg, Texas 78539
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Namias A, Jobe NB, Paaijmans KP, Huijben S. The need for practical insecticide-resistance guidelines to effectively inform mosquito-borne disease control programs. eLife 2021; 10:e65655. [PMID: 34355693 PMCID: PMC8346280 DOI: 10.7554/elife.65655] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 07/26/2021] [Indexed: 11/13/2022] Open
Abstract
Monitoring local mosquito populations for insecticide resistance is critical for effective vector-borne disease control. However, widely used phenotypic assays, which are designed to monitor the emergence and spread of insecticide resistance (technical resistance), do not translate well to the efficacy of vector control products to suppress mosquito numbers in the field (practical resistance). This is because standard testing conditions such as environmental conditions, exposure dose, and type of substrate differ dramatically from those experienced by mosquitoes under field conditions. In addition, field mosquitoes have considerably different physiological characteristics such as age and blood-feeding status. Beyond this, indirect impacts of insecticide resistance and/or exposure on mosquito longevity, pathogen development, host-seeking behavior, and blood-feeding success impact disease transmission. Given the limited number of active ingredients currently available and the observed discordance between resistance and disease transmission, we conclude that additional testing guidelines are needed to determine practical resistance-the efficacy of vector control tools under relevant local conditions- in order to obtain programmatic impact.
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Affiliation(s)
- Alice Namias
- Département de Biologie, Ecole Normale Supérieure, PSL Research University, Paris, France
- Institut des Sciences de l'Evolution de Montpellier (ISEM), Université de Montpellier, CNRS, IRD, EPHE, Montpellier, France
| | - Ndey Bassin Jobe
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Life Sciences C, Tempe, United States
| | - Krijn Petrus Paaijmans
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Life Sciences C, Tempe, United States
- The Biodesign Center for Immunotherapy, Vaccines and Virotherapy, Arizona State University, Biodesign Institute, Tempe, United States
- ISGlobal, Carrer del Rosselló, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Distrito da Manhiça, Mozambique
| | - Silvie Huijben
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Life Sciences C, Tempe, United States
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Gleave K, Lissenden N, Chaplin M, Choi L, Ranson H. Piperonyl butoxide (PBO) combined with pyrethroids in insecticide-treated nets to prevent malaria in Africa. Cochrane Database Syst Rev 2021; 5:CD012776. [PMID: 34027998 PMCID: PMC8142305 DOI: 10.1002/14651858.cd012776.pub3] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Pyrethroid long-lasting insecticidal nets (LLINs) have been important in the large reductions in malaria cases in Africa, but insecticide resistance in Anopheles mosquitoes threatens their impact. Insecticide synergists may help control insecticide-resistant populations. Piperonyl butoxide (PBO) is such a synergist; it has been incorporated into pyrethroid-LLINs to form pyrethroid-PBO nets, which are currently produced by five LLIN manufacturers and, following a recommendation from the World Health Organization (WHO) in 2017, are being included in distribution campaigns. This review examines epidemiological and entomological evidence on the addition of PBO to pyrethroid nets on their efficacy. OBJECTIVES To compare effects of pyrethroid-PBO nets currently in commercial development or on the market with effects of their non-PBO equivalent in relation to: 1. malaria parasite infection (prevalence or incidence); and 2. entomological outcomes. SEARCH METHODS We searched the Cochrane Infectious Diseases Group (CIDG) Specialized Register, CENTRAL, MEDLINE, Embase, Web of Science, CAB Abstracts, and two clinical trial registers (ClinicalTrials.gov and WHO International Clinical Trials Registry Platform) up to 25 September 2020. We contacted organizations for unpublished data. We checked the reference lists of trials identified by these methods. SELECTION CRITERIA We included experimental hut trials, village trials, and randomized controlled trials (RCTs) with mosquitoes from the Anopheles gambiae complex or the Anopheles funestus group. DATA COLLECTION AND ANALYSIS Two review authors assessed each trial for eligibility, extracted data, and determined the risk of bias for included trials. We resolved disagreements through discussion with a third review author. We analysed data using Review Manager 5 and assessed the certainty of evidence using the GRADE approach. MAIN RESULTS Sixteen trials met the inclusion criteria: 10 experimental hut trials, four village trials, and two cluster-RCTs (cRCTs). Three trials are awaiting classification, and four trials are ongoing. Two cRCTs examined the effects of pyrethroid-PBO nets on parasite prevalence in people living in areas with highly pyrethroid-resistant mosquitoes (< 30% mosquito mortality in discriminating dose assays). At 21 to 25 months post intervention, parasite prevalence was lower in the intervention arm (odds ratio (OR) 0.79, 95% confidence interval (CI) 0.67 to 0.95; 2 trials, 2 comparisons; moderate-certainty evidence). In highly pyrethroid-resistant areas, unwashed pyrethroid-PBO nets led to higher mosquito mortality compared to unwashed standard-LLINs (risk ratio (RR) 1.84, 95% CI 1.60 to 2.11; 14,620 mosquitoes, 5 trials, 9 comparisons; high-certainty evidence) and lower blood feeding success (RR 0.60, 95% CI 0.50 to 0.71; 14,000 mosquitoes, 4 trials, 8 comparisons; high-certainty evidence). However, in comparisons of washed pyrethroid-PBO nets to washed LLINs, we do not know if PBO nets had a greater effect on mosquito mortality (RR 1.20, 95% CI 0.88 to 1.63; 10,268 mosquitoes, 4 trials, 5 comparisons; very low-certainty evidence), although the washed pyrethroid-PBO nets did decrease blood-feeding success compared to standard-LLINs (RR 0.81, 95% CI 0.72 to 0.92; 9674 mosquitoes, 3 trials, 4 comparisons; high-certainty evidence). In areas where pyrethroid resistance is moderate (31% to 60% mosquito mortality), mosquito mortality was higher with unwashed pyrethroid-PBO nets compared to unwashed standard-LLINs (RR 1.68, 95% CI 1.33 to 2.11; 751 mosquitoes, 2 trials, 3 comparisons; moderate-certainty evidence), but there was little to no difference in effects on blood-feeding success (RR 0.90, 95% CI 0.72 to 1.11; 652 mosquitoes, 2 trials, 3 comparisons; moderate-certainty evidence). For washed pyrethroid-PBO nets compared to washed standard-LLINs, we found little to no evidence for higher mosquito mortality or reduced blood feeding (mortality: RR 1.07, 95% CI 0.74 to 1.54; 329 mosquitoes, 1 trial, 1 comparison, low-certainty evidence; blood feeding success: RR 0.91, 95% CI 0.74 to 1.13; 329 mosquitoes, 1 trial, 1 comparison; low-certainty evidence). In areas where pyrethroid resistance is low (61% to 90% mosquito mortality), studies reported little to no difference in the effects of unwashed pyrethroid-PBO nets compared to unwashed standard-LLINs on mosquito mortality (RR 1.25, 95% CI 0.99 to 1.57; 948 mosquitoes, 2 trials, 3 comparisons; moderate-certainty evidence), and we do not know if there was any effect on blood-feeding success (RR 0.75, 95% CI 0.27 to 2.11; 948 mosquitoes, 2 trials, 3 comparisons; very low-certainty evidence). For washed pyrethroid-PBO nets compared to washed standard-LLINs, we do not know if there was any difference in mosquito mortality (RR 1.39, 95% CI 0.95 to 2.04; 1022 mosquitoes, 2 trials, 3 comparisons; very low-certainty evidence) or on blood feeding (RR 1.07, 95% CI 0.49 to 2.33; 1022 mosquitoes, 2 trials, 3 comparisons; low-certainty evidence). In areas where mosquito populations are susceptible to insecticides (> 90% mosquito mortality), there may be little to no difference in the effects of unwashed pyrethroid-PBO nets compared to unwashed standard-LLINs on mosquito mortality (RR 1.20, 95% CI 0.64 to 2.26; 2791 mosquitoes, 2 trials, 2 comparisons; low-certainty evidence). This is similar for washed nets (RR 1.07, 95% CI 0.92 to 1.25; 2644 mosquitoes, 2 trials, 2 comparisons; low-certainty evidence). We do not know if unwashed pyrethroid-PBO nets had any effect on the blood-feeding success of susceptible mosquitoes (RR 0.52, 95% CI 0.12 to 2.22; 2791 mosquitoes, 2 trials, 2 comparisons; very low-certainty evidence). The same applies to washed nets (RR 1.25, 95% CI 0.82 to 1.91; 2644 mosquitoes, 2 trials, 2 comparisons; low-certainty evidence). In village trials comparing pyrethroid-PBO nets to LLINs, there was no difference in sporozoite rate (4 trials, 5 comparisons) nor in mosquito parity (3 trials, 4 comparisons). AUTHORS' CONCLUSIONS In areas of high insecticide resistance, pyrethroid-PBO nets have greater entomological and epidemiological efficacy compared to standard LLINs, with sustained reduction in parasite prevalence, higher mosquito mortality and reduction in mosquito blood feeding rates 21 to 25 months post intervention. Questions remain about the durability of PBO on nets, as the impact of pyrethroid-PBO nets on mosquito mortality was not sustained over 20 washes in experimental hut trials, and epidemiological data on pyrethroid-PBO nets for the full intended three-year life span of the nets is not available. Little evidence is available to support greater entomological efficacy of pyrethroid-PBO nets in areas where mosquitoes show lower levels of resistance to pyrethroids.
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Affiliation(s)
- Katherine Gleave
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Natalie Lissenden
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Marty Chaplin
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Leslie Choi
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Hilary Ranson
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
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9
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Ahsan A, Haider N, Kock R, Benfield C. Possible Drivers of the 2019 Dengue Outbreak in Bangladesh: The Need for a Robust Community-Level Surveillance System. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:37-39. [PMID: 32725192 DOI: 10.1093/jme/tjaa150] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Indexed: 06/11/2023]
Affiliation(s)
- Atik Ahsan
- LEARN Dengue Outbreak Project, The Start Fund Bangladesh, Dhaka, Bangladesh
| | - Najmul Haider
- The Royal Veterinary College, University of London, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire, United Kingdom
| | - Richard Kock
- The Royal Veterinary College, University of London, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire, United Kingdom
| | - Camilla Benfield
- The Royal Veterinary College, University of London, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire, United Kingdom
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10
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Parker C. Collection and Rearing of Container Mosquitoes and a 24-h Addition to the CDC Bottle Bioassay. JOURNAL OF INSECT SCIENCE (ONLINE) 2020; 20:13. [PMID: 33135763 PMCID: PMC7751146 DOI: 10.1093/jisesa/ieaa059] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Indexed: 06/11/2023]
Abstract
Container mosquitoes (Diptera: Culicidae) oviposit their eggs in both natural and artificial containers. Many container mosquito species also serve as important vectors of disease-causing pathogens including Aedes aegypti, Ae. albopictus, and Ae. triseriatus. Control of these species can be done through the use of adulticide sprays. The efficacy of these treatments is highly dependent on the insecticide susceptibility status of the local mosquito populations. This paper provides protocols on collecting and rearing container mosquitoes for use in the Centers for Disease Control and Prevention (CDC) bottle bioassay. A brief description of the CDC bottle bioassay is provided as well as a standardized protocol for the incorporation of a 24-h mortality to the CDC bottle bioassay. Results from this 24-h holding addition to the CDC bottle bioassay reveal that some forms of resistance may be missed without the incorporation of the additional mortality reading. These protocols provide a foundation for new laboratories to establish rearing protocols and begin conducting resistance monitoring.
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Affiliation(s)
- Casey Parker
- University of Florida, Institute of Food and Agricultural Sciences, Florida Medical Entomology Laboratory, Vero Beach, FL
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11
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Pareja-Loaiza PX, Santacoloma Varon L, Rey Vega G, Gómez-Camargo D, Maestre-Serrano R, Lenhart A. Mechanisms associated with pyrethroid resistance in populations of Aedes aegypti (Diptera: Culicidae) from the Caribbean coast of Colombia. PLoS One 2020; 15:e0228695. [PMID: 33022007 PMCID: PMC7537870 DOI: 10.1371/journal.pone.0228695] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 09/23/2020] [Indexed: 11/18/2022] Open
Abstract
Aedes aegypti is the main vector of dengue, chikungunya, and Zika viruses, which are of great public health importance in Colombia. Aedes control strategies in Colombia rely heavily on the use of organophosphate and pyrethroid insecticides, providing constant selection pressure and the emergence of resistant populations. In recent years, insecticide use has increased due to the increased incidence of dengue and recent introductions of chikungunya and Zika. In the present study, pyrethroid resistance was studied across six populations of Ae. aegypti from the Caribbean coast of Colombia. Susceptibility to λ-cyhalothrin, deltamethrin, and permethrin was assessed, and resistance intensity was determined. Activity levels of enzymes associated with resistance were measured, and the frequencies of three kdr alleles (V1016I, F1534C, V410L) were calculated. Results showed variations in pyrethroid susceptibility across Ae. aegypti populations and altered enzyme activity levels were detected. The kdr alleles were detected in all populations, with high variations in frequencies: V1016I (frequency ranging from 0.15-0.70), F1534C (range 0.94-1.00), and V410L (range 0.05-0.72). In assays of phenotyped individuals, associations were observed between the presence of V1016I, F1534C, and V410L alleles and resistance to the evaluated pyrethroids, as well as between the VI1016/CC1534/VL410 tri-locus genotype and λ-cyhalothrin and permethrin resistance. The results of the present study contribute to the knowledge of the mechanisms underlying the resistance to key pyrethroids used to control Ae. aegypti along the Caribbean coast of Colombia.
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Affiliation(s)
- Paula X. Pareja-Loaiza
- Estudiante, Doctorados Nacionales Colciencias, Grupo UNIMOL, Doctorado en Medicina Tropical, Facultad de Medicina, Universidad de Cartagena, Cartagena de Indias, Colombia
| | - Liliana Santacoloma Varon
- Laboratorio de Entomologia, Subdireccion Laboratorio Nacional de Referencia, Direccion Redes en Salud Publica, Instituto Nacional de Salud, Bogotá, Colombia
| | - Gabriela Rey Vega
- Laboratorio de Entomologia, Subdireccion Laboratorio Nacional de Referencia, Direccion Redes en Salud Publica, Instituto Nacional de Salud, Bogotá, Colombia
| | - Doris Gómez-Camargo
- Grupo UNIMOL, Doctorado en Medicina Tropical, Facultad de Medicina, Universidad de Cartagena, Cartagena de Indias, Colombia
| | | | - Audrey Lenhart
- Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
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12
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Richards SL, Byrd BD, Reiskind MH, White AV. Assessing Insecticide Resistance in Adult Mosquitoes: Perspectives on Current Methods. ENVIRONMENTAL HEALTH INSIGHTS 2020; 14:1178630220952790. [PMID: 32952401 PMCID: PMC7477762 DOI: 10.1177/1178630220952790] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 07/30/2020] [Indexed: 06/02/2023]
Abstract
Mosquito insecticide resistance (IR) is a growing global issue that must be addressed to protect public health. Vector control programs (VCPs) should regularly monitor local mosquito populations for IR and plan control measures accordingly. In some cases, state/federal resources financially support this testing with expertise and/or training programs. Standardization of methods (eg, Centers for Disease Control and Prevention bottle bioassay, World Health Organization tube testing, dose-mortality bioassay) for monitoring IR must be prioritized. One solution is regional hubs of IR monitoring at the state or other level. Training programs on methodology and interpretation of results should be developed and routinely offered to local VCPs conducting IR testing in mosquitoes. Here, current methods for assessing mosquito IR are discussed and insights into a variety of questions from VCPs are considered. It is critical that methods for IR monitoring and data interpretation are standardized through routine training, with the goal of evidence-driven decision making to improve control of mosquitoes and mosquito-borne disease.
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Affiliation(s)
- Stephanie L Richards
- Department of Health Education and Promotion, East Carolina University, Environmental Health Science Program, Greenville, NC, USA
| | - Brian D Byrd
- Western Carolina University, Environmental Health Science Program, Cullowhee, NC, USA
| | - Michael H Reiskind
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, USA
| | - Avian V White
- Department of Health Education and Promotion, East Carolina University, Environmental Health Science Program, Greenville, NC, USA
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13
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Disi JO, Van Timmeren S, Gress B, Zalom F, Isaacs R, Sial A. Insecticide residue longevity for on-site screening of Drosophila suzukii (Matsumura) resistance. PEST MANAGEMENT SCIENCE 2020; 76:2918-2924. [PMID: 32356402 DOI: 10.1002/ps.5880] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 04/24/2020] [Accepted: 04/30/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Preventative application of insecticides reduces marketable yield losses caused by Drosophila suzukii females that selectively lay eggs into ripe and ripening fruits. However, repeated applications of insecticides increase the risk of resistance development. It is therefore critical to test field-collected flies on-site to assess the level of sensitivity of D. suzukii to insecticides to monitor resistance, before it becomes a widespread issue. This requires that insecticide-treated vials be readily available to conduct bioassays. Thus, bioassays were conducted using malathion-, methomyl-, zeta-cypermethrin-, phosmet-, spinetoram- and spinosad-treated scintillation vials at 1 to 28 days after treatment to assess how residue age affects insecticide toxicity in scintillation vials. The impact of temperature on residue longevity was also assessed. RESULTS Insecticide-treated vials stored for 28 days provided reliable estimates of susceptibility of D. suzukii to some of the tested insecticides. The toxicity of malathion remained consistently high throughout the experiment followed by methomyl. However, toxicities of zeta-cypermethrin, phosmet were variable whereas those of the spinosyns declined relatively quickly. Overall, storage temperature did not affect the residual toxicity of most of the tested insecticides except zeta-cypermethrin. CONCLUSION These findings suggest that the toxicity of insecticide residues in treated vials remains active for ≤28 d for malathion and ≤21 and 28 days in methomyl-treated vials stored at 4 °C in Georgia and Michigan, respectively. However, the toxicities of spinosad, zeta-cypermethrin and phosmet were less consistent. Hence, vials treated with these insecticides should be freshly made to be effective for screening D. suzukii field populations for resistance. © 2020 Society of Chemical Industry.
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Affiliation(s)
| | | | - Brian Gress
- Department of Entomology & Nematology, University of California, Davis, CA, USA
| | - Frank Zalom
- Department of Entomology & Nematology, University of California, Davis, CA, USA
| | - Rufus Isaacs
- Department of Entomology, Michigan State University, East Lansing, MI, USA
| | - Ashfaq Sial
- Department of Entomology, University of Georgia, Athens, GA, USA
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14
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Ninditya VI, Purwati E, Utami AT, Marwaningtyaz AS, Fairuz NK, Widayanti R, Hamid PH. Artemisia vulgaris efficacies against various stages of Aedes aegypti. Vet World 2020; 13:1423-1429. [PMID: 32848320 PMCID: PMC7429375 DOI: 10.14202/vetworld.2020.1423-1429] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 05/28/2020] [Indexed: 11/16/2022] Open
Abstract
Background and Aim: Aedes aegypti is the vector of dengue fever, dengue hemorrhagic fever, chikungunya, and, most recently, Zika. Dengue fever is one of Indonesia’s endemic diseases. The principal tool for preventing dengue is controlling Ae. aegypti by chemical insecticides since vaccine against dengue is still under research. However, Ae. aegypti developed resistance to various chemical insecticides worldwide. Therefore, research on alternate compounds as mosquito insecticides is urgently needed. This study demonstrated the efficacy of Artemisia vulgaris extract as larvicidal, ovicidal, adulticidal, repellency, and oviposition deterrent activity against Ae. aegypti. Materials and Methods: A. vulgaris was obtained from Temanggung, Indonesia, while the eggs of Ae. aegypti were collected from Yogyakarta, Indonesia, and were hatched in Laboratory of Parasitology, Faculty of Veterinary Medicine, Universitas Gadjah Mada. Larvicidal activity was evaluated according to the WHO protocol; adulticidal activity was performed using the Centers for Disease Control protocol. Oviposition activity was evaluated using ovitraps added with A. vulgaris extract, complete protection time in the repellent assay was defined as the number of minutes elapsed between compound application and the landing of the first mosquito. Results: A test of the larvicidal activity of A. vulgaris extract returned an LC50 of 65.8 ppm (r2=0.9014) in 1 h and 18.6 ppm (r2=0.575) in 24 h. A. vulgaris was effective as an adulticidal, demonstrating LC50 values of 11.35 mg (r2=0.875) in 90 min, 9.63 mg (r2=0.924) in 105 min, and 6.46 mg (r2=0.925) in 120 min. A. vulgaris at a concentration of 1000 ppm was able to reach 96% of oviposition deterrent effect. The ovicidal assay, a concentration of 1000 ppm resulted in 82.67% of eggs remaining unhatched. An extract concentration of 80 mg/ml achieved 63.3±3.5% biting repellency in adults. Conclusion: This study gives a clear indication that A. vulgaris extract acts on Ae. aegypti at various developmental stages and is a potential alternative bioinsecticide for controlling this disease vector.
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Affiliation(s)
| | - Endah Purwati
- Faculty of Veterinary Medicine, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Ajeng Tyas Utami
- Faculty of Veterinary Medicine, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | | | | | - Rini Widayanti
- Faculty of Veterinary Medicine, Universitas Gadjah Mada, Yogyakarta, Indonesia
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15
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Lucas KJ, Bales RB, McCoy K, Weldon C. Oxidase, Esterase, and KDR-Associated Pyrethroid Resistance in Culex quinquefasciatus Field Collections of Collier County, Florida. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2020; 36:22-32. [PMID: 32497474 DOI: 10.2987/19-6850.1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In several insect species, resistance to pyrethroids and DDT (dichlorodiphenyltrichloroethane) is linked to point mutations in the voltage-gated sodium channel (VGSC) gene. Pyrethroid-based insecticides prolong the opening of sodium channels, causing paralysis known as a "knockdown" effect before mortality occurs. Point mutations in the VGSC gene result in decreased pyrethroid binding and reduced sensitivity to the insecticide-this resistance mechanism is known as knockdown resistance (kdr) as insects do not die but recover from paralysis with time. In Culex mosquito species loss of target site sensitivity to pyrethroids is linked to a number of substitutions, one of which is leucine (L) to phenylalanine (F) at residue 1014 (L1014F) in the VGSC gene. Here we report the identification of kdr-associated pyrethroid resistance and developing resistance in Cx. quinquefasciatus field collections from Collier County, FL. Evaluation of position 1014 of the VGSC in Cx. quinquefasciatus collections from 7 locations in Collier County, FL, revealed a wide range of genotypes from one part of the district to the other. Centers for Disease Control and Prevention bottle bioassay, linear regression analysis, and cage trial evaluations suggest that the L1014F mutation plays a role, at least in part, to the pyrethroid resistance status of Cx. quinquefasciatus collected in Collier County, FL. Furthermore, we identified resistance attributed to both oxidase and esterase activity, indicating that multiple mechanisms are responsible for pyrethroid resistance in Collier County Cx. quinquefasciatus.
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16
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Ser O, Cetin H. Investigation of Susceptibility Levels of Culex pipiens L. (Diptera: Culicidae) Populations to Synthetic Pyrethroids in Antalya Province of Turkey. J Arthropod Borne Dis 2019; 13:243-258. [PMID: 31879665 PMCID: PMC6928386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 06/26/2019] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Culex pipiens L. (Diptera: Culicidae) is an important vector of several pathogens. This mosquito is widely distributed throughout the world. We aimed to determine the susceptibility levels of Cx. pipiens populations to some synthetic pyrethroid insecticides in Antalya, Turkey. METHODS The immature stages of mosquitoes were collected from eight locations in Alanya, Döşemealtı, Kemer, Kumluca, and Manavgat districts of Antalya between Apr and Oct of 2017. Adult susceptibility tests were carried out according to a modified version of the Centers for Disease Control and Prevention bottle bioassay. In the tests, the World Health Organization recommended diagnostic doses; permethrin (0.75%), etofenprox (0.5%), deltamethrin (0.05%) and lambda-cyhalothrin (0.05%) were used. RESULTS As a result of the susceptibility tests, deltamethrin was the least effective insecticide and it caused 58.78-97.56% mortalities on Cx. pipiens populations while permethrin was the most effective substance that caused 100% mortality on all populations. While all of the tested populations were found susceptible to permethrin, and possible resistant or resistant to deltamethrin. Etofenprox and lambda-cyhalothrin led to 91.54-100% and 93.1-100% mortalities, respectively. CONCLUSION The possible resistance or resistance to deltamethrin in all the areas is caused by the widespread use of this chemical against pests in agriculture and public health applications for long-term. Moreover, a concordance was found between resistance levels and the intensity of pesticide application in agriculture and public health, and organic and chemical pollution levels in the sampled habitats.
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Affiliation(s)
- Onder Ser
- Malaria Control Unit, Antalya Provincial Directorate of Health, Antalya, Turkey,Corresponding author: Dr Onder Ser, E-mail:
| | - Huseyin Cetin
- Department of Biology, Faculty of Science, Akdeniz University, Antalya, Turkey
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17
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Vatandoost H, Abai MR, Akbari M, Raeisi A, Yousefi H, Sheikhi S, Bagheri A. Comparison of CDC Bottle Bioassay with WHO Standard Method for Assessment Susceptibility Level of Malaria Vector, Anopheles stephensi to Three Imagicides. J Arthropod Borne Dis 2019; 13:17-26. [PMID: 31346532 PMCID: PMC6643010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 04/16/2018] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND The detection of insecticide resistance in natural populations of Anopheles vectors is absolutely necessary for malaria control. CDC bottle bioassay as a new tools has been employed for detecting the insecticide resistance. For a limit number of mosquito vectors, diagnostic doses and diagnostic times for some insecticides have already been determined using this new assay. For the first time in the area, susceptibility levels of Anopheles stephensi was done with DDT, deltamethrin, and bendiocarb using CDC bottle bioassay and compared results with WHO standard test method. METHODS Anopheles stephensi were collected in larvae stage from the cisterns of drinking water in Chabahar port which considered as old malaria foci, Sistan and Baluchistan province. The field collected larvae were colonized at the insectary of School of Public Health (SPH), Tehran University of Medical Science. The susceptibility tests were carried out on sugar fed female mosquitoes aged 2-3 days, against DDT 4%, bendiocarb 1% and deltamethrin 0.05% using WHO and CDC susceptibility methods. The mortality and knockdown rates, as well as the parameters of regression analysis, including LT50 and LT90, was calculated separately for the WHO and CDC methods. RESULTS The 24h mortality rates of An. stephensi were 28.6% and 25.6% for DDT, 60.8% and 64.6% for bendiocarb and 100% for deltamethrin using both WHO and CDC assay at 30 and 60min respectively. The 50% lethal times (LT50) were estimated 44.9 and 66.2min, 38.9 and 81.8min and 0.7 and 15.0min respectively using both WHO and CDC susceptibility tests. CONCLUSION The similar results of susceptibility levels were shown for DDT, bendiocarb and deltamethrin. The lethal times (LT50) showed significant difference using both WHO and CDC bioassay methods.
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Affiliation(s)
- Hassan Vatandoost
- Department of Medical Entomology and Vector Control, School of Public Health and National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran,Department of Chemical Pollutants and Pesticides, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran,Corresponding authors: Prof Hassan Vatandoost, E-mail: , Mr Mohammad Reza Abai, E-mail:
| | - Mohammad Reza Abai
- Department of Medical Entomology and Vector Control, School of Public Health and National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran,Department of Chemical Pollutants and Pesticides, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran,Corresponding authors: Prof Hassan Vatandoost, E-mail: , Mr Mohammad Reza Abai, E-mail:
| | - Morteza Akbari
- Department of Medical Entomology and Vector Control, School of Public Health and National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Raeisi
- Department of Malaria, Center for Disease Control (CDC), Ministry of Health and Medical Education, Tehran, Iran
| | - Hemn Yousefi
- Department of Medical Entomology and Vector Control, School of Public Health and National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Soraya Sheikhi
- Department of Medical Entomology and Vector Control, School of Public Health and National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Akbar Bagheri
- Department of Medical Entomology and Vector Control, School of Public Health and National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran
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18
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Olatunbosun-Oduola A, Abba E, Adelaja O, Taiwo-Ande A, Poloma-Yoriyo K, Samson-Awolola T. Widespread Report of Multiple Insecticide Resistance in Anopheles gambiae s.l. Mosquitoes in Eight Communities in Southern Gombe, North-Eastern Nigeria. J Arthropod Borne Dis 2019; 13:50-61. [PMID: 31346535 PMCID: PMC6643017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 01/08/2019] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Timely entomological and insecticide resistance monitoring is a key to generating relevant data for vector management. We investigated the insecticide susceptibility status of Anopheles gambiae s.l. in eight rural farming communities in Southern Gombe, Nigeria. METHODS Overall, 3-5 days-old adult female Anopheles mosquitoes reared from field-collected immature stages between September and November, 2014 were exposed to the diagnostic doses of pyrethroids, organophosphate and carbamate insecticides using the Center for Disease Control Bottle bioassay. The observatory knockdown time from exposure to each insecticide was recorded up to two hours. The dead mosquitoes were then identified morphologically and by molecular assays. RESULTS Mortality results showed resistance in An. gambiae s.l. populations to bendiocarb (2.3-100%), deltamethrin (39-70%), pirimiphos-methyl (65-95%), dichloro-diphenyl-trichloroethane (0-38.1%), permethrin (0-46.3%) and lambda-cyhalothrin (42.5-86.4%). The few cases of full susceptibility were observed from lamdacyhalothrin exposed population of An. gambiae s.l. in Banbam and Pantami respectively. An. gambiae 177 (45%) was significantly higher (P< 0.05) than An. arabiensis 64 (16.3%), An. coluzzii 34 (8.7%) and An. gambiae/An. coluzzii hybrid 78 (19.8%). CONCLUSION A strong evidence of widespread resistance in the major malaria vector species in Southern Gombe to all common classes of insecticides is a justification for the State Malaria Elimination Programme to consciously consider incorporating insecticide resistance management strategies into control programs in order to sustain the future of current control interventions.
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Affiliation(s)
- Adedayo Olatunbosun-Oduola
- Department of Zoology, University of Ilorin, Ilorin, Kwara State, Nigeria,Corresponding author: Dr Adedayo Olatunbosun Oduola, E-mail:
| | - Ezra Abba
- Department of Biological Sciences, Faculty of Science, Gombe State University PMB 127, Gombe, Nigeria
| | - Olukayode Adelaja
- Department of Zoology, University of Ilorin, Ilorin, Kwara State, Nigeria
| | - Adeolu Taiwo-Ande
- Department of Zoology, University of Ilorin, Ilorin, Kwara State, Nigeria
| | - Kennedy Poloma-Yoriyo
- Department of Biological Sciences, Faculty of Science, Gombe State University PMB 127, Gombe, Nigeria
| | - Taiwo Samson-Awolola
- Public Health Division and Epidemiology, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria
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19
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Gleave K, Lissenden N, Richardson M, Choi L, Ranson H. Piperonyl butoxide (PBO) combined with pyrethroids in insecticide-treated nets to prevent malaria in Africa. Cochrane Database Syst Rev 2018; 11:CD012776. [PMID: 30488945 PMCID: PMC6262905 DOI: 10.1002/14651858.cd012776.pub2] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Public health strategies that target mosquito vectors, particularly pyrethroid long-lasting insecticidal nets (LLINs), have been largely responsible for the substantial reduction in the number of people in Africa developing malaria. The spread of insecticide resistance in Anopheles mosquitoes threatens these impacts. One way to control insecticide-resistant populations is by using insecticide synergists. Piperonyl butoxide (PBO) is a synergist that inhibits specific metabolic enzymes within mosquitoes and has been incorporated into pyrethroid-LLINs to form pyrethroid-PBO nets. Pyrethroid-PBO nets are currently produced by four LLIN manufacturers and, following a recommendation from the World Health Organization (WHO) in 2017, are being included in distribution campaigns in countries. This review examines epidemiological and entomological evidence on whether the addition of PBO to LLINs improves their efficacy. OBJECTIVES 1. Evaluate whether adding PBO to pyrethroid LLINs increases the epidemiological and entomological effectiveness of the nets.2. Compare the effects of pyrethroid-PBO nets currently in commercial development or on the market with their non-PBO equivalent in relation to:a. malaria infection (prevalence or incidence);b. entomological outcomes. SEARCH METHODS We searched the Cochrane Infectious Diseases Group (CIDG) Specialized Register; CENTRAL, MEDLINE, Embase, Web of Science, CAB Abstracts, and two clinical trial registers (ClinicalTrials.gov and WHO International Clinical Trials Registry Platform) up to 24 August 2018. We contacted organizations for unpublished data. We checked the reference lists of trials identified by the above methods. SELECTION CRITERIA We included laboratory trials, experimental hut trials, village trials, and randomized clinical trials with mosquitoes from the Anopheles gambiae complex or Anopheles funestus group. DATA COLLECTION AND ANALYSIS Two review authors assessed each trial for eligibility, extracted data, and determined the risk of bias for included trials. We resolved disagreements through discussion with a third review author. We analysed the data using Review Manager 5 and assessed the certainty of the evidence using the GRADE approach. MAIN RESULTS Fifteen trials met the inclusion criteria: two laboratory trials, eight experimental hut trials, and five cluster-randomized controlled village trials.One village trial examined the effect of pyrethroid-PBO nets on malaria infection prevalence in an area with highly pyrethroid-resistant mosquitoes. The latest endpoint at 21 months post-intervention showed that malaria prevalence probably decreased in the intervention arm (OR 0.40, 95% CI 0.20 to 0.80; 1 trial, 1 comparison, moderate-certainty evidence).In highly pyrethroid-resistant areas (< 30% mosquito mortality), in comparisons of unwashed pyrethroid-PBO nets to unwashed standard-LLINs, PBO nets resulted in higher mosquito mortality (risk ratio (RR) 1.84, 95% CI 1.60 to 2.11; 14,620 mosquitoes, 5 trials, 9 comparisons, high-certainty evidence) and lower blood feeding success (RR 0.60, 95% CI 0.50 to 0.71; 14,000 mosquitoes, 4 trials, 8 comparisons, high-certainty evidence). However, in comparisons of washed pyrethroid-PBO nets to washed LLINs we do not know if PBO nets have a greater effect on mosquito mortality (RR 1.20, 95% CI 0.88 to 1.63; 10,268 mosquitoes, 4 trials, 5 comparisons, very low-certainty evidence), although the washed pyrethroid-PBO nets do decrease blood feeding success compared to standard-LLINs (RR 0.81, 95% CI 0.72 to 0.92; 9674 mosquitoes, 3 trials, 4 comparisons, high-certainty evidence).In areas where pyrethroid resistance is considered moderate (31% to 60% mosquito mortality), there may be little or no difference in effects of unwashed pyrethroid-PBO nets compared to unwashed standard-LLINs on mosquito mortality (RR 1.16, 95% CI 0.88 to 1.54; 242 mosquitoes, 1 trial, 1 comparison, low-certainty evidence), and there may be little or no difference in the effects on blood feeding success (RR 0.87, 95% CI 0.67 to 1.13; 242 mosquitoes, 1 trial, 1 comparison, low-certainty evidence). The same pattern is apparent for washed pyrethroid-PBO nets compared to washed standard-LLINs (mortality: RR 1.07, 95% CI 0.74 to 1.54; 329 mosquitoes, 1 trial, 1 comparison, low-certainty evidence; blood feeding success: RR 0.91, 95% CI 0.74 to 1.13; 329 mosquitoes, 1 trial, 1 comparison, low-certainty evidence).In areas where pyrethroid resistance is low (61% to 90% mosquito mortality), there is probably little or no difference in the effect of unwashed pyrethroid-PBO nets compared to unwashed standard-LLINs on mosquito mortality (RR 1.10, 95% CI 1.05 to 1.16; 708 mosquitoes, 1 trial, 2 comparisons, moderate-certainty evidence), but there is no evidence for an effect on blood feeding success (RR 0.67, 95% CI 0.06 to 7.37; 708 mosquitoes, 1 trial, 2 comparisons, very low-certainty evidence). For washed pyrethroid-PBO nets compared to washed standard-LLINs we do not know if there is any difference in mosquito mortality (RR 1.16, 96% CI 0.83 to 1.63; 878 mosquitoes, 1 trial, 2 comparisons, very low-certainty evidence), but blood feeding may decrease (RR 1.50, 95% CI 0.89 to 2.54; 878 mosquitoes, 1 trial, 2 comparisons, low-certainty evidence).In areas were mosquito populations are susceptible to insecticides (> 90% mosquito mortality), there may be little or no difference in the effect of unwashed pyrethroid-PBO nets compared to unwashed standard-LLINs on mosquito mortality (RR 1.20, 95% CI 0.64 to 2.26; 2791 mosquitoes, 2 trials, 2 comparisons, low-certainty evidence). This is similar for washed nets (RR 1.07, 95% CI 0.92 to 1.25; 2644 mosquitoes, 2 trials, 2 comparisons, low-certainty evidence). We do not know if unwashed pyrethroid-PBO nets have any effect on blood feeding success of susceptible mosquitoes (RR 0.50, 95% CI 0.11 to 2.32; 2791 mosquitoes, 2 trials, 2 comparisons, very low-certainty evidence). The same applies to washed nets (RR 1.28, 95% CI 0.81 to 2.04; 2644 mosquitoes, 2 trials, 2 comparisons, low-certainty evidence).In village trials comparing pyrethroid-PBO nets to LLINs, there was no difference in sporozoite rate (4 trials, 5 comparison) and mosquito parity (3 trials, 4 comparisons). AUTHORS' CONCLUSIONS In areas of high insecticide resistance, pyrethroid-PBO nets reduce mosquito mortality and blood feeding rates, and results from a single clinical trial demonstrate that this leads to lower malaria prevalence. Questions remain about the durability of PBO on nets, as the impact of pyrethroid-PBO LLINs on mosquito mortality was not sustained over 20 washes in experimental hut trials. There is little evidence to support higher entomological efficacy of pyrethroid-PBO nets in areas where the mosquitoes show lower levels of resistance to pyrethroids.
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Affiliation(s)
- Katherine Gleave
- Liverpool School of Tropical MedicineDepartment of Vector BiologyPembroke PlaceLiverpoolUKL3 5QA
| | - Natalie Lissenden
- Liverpool School of Tropical MedicineDepartment of Vector BiologyPembroke PlaceLiverpoolUKL3 5QA
| | - Marty Richardson
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesPembroke PlaceLiverpoolUKL3 5QA
| | - Leslie Choi
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesPembroke PlaceLiverpoolUKL3 5QA
| | - Hilary Ranson
- Liverpool School of Tropical MedicineDepartment of Vector BiologyPembroke PlaceLiverpoolUKL3 5QA
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Redox state affects fecundity and insecticide susceptibility in Anopheles gambiae. Sci Rep 2018; 8:13054. [PMID: 30158658 PMCID: PMC6115382 DOI: 10.1038/s41598-018-31360-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 08/19/2018] [Indexed: 01/02/2023] Open
Abstract
Redox reactions play a central role in the metabolism of an organism. It is vital to maintain redox homeostasis in response to the fluctuation of redox shift in various biological contexts. NADPH-dependent reducing capacity is one of the key factors contributing to the redox homeostasis. To understand the redox capacity and its impact on mosquito fecundity and susceptibility to insecticides in Anopheles gambiae, we examined the dynamics of elevated oxidative state via induction by paraquat (PQ) and the inhibition of NADPH regeneration by 6-aminonicotinamide (6AN). In naïve conditions, inherent oxidative capacity varies between individuals, as measured by GSSG/GSH ratio. The high GSSG/GSH ratio was negatively correlated with fecundity. Both PQ and 6AN feeding increased GSSG/GSH ratio and elevated protein carbonylation, a marker of oxidative damage. Both pro-oxidants lowered egg production. Co-feeding the pro-oxidants with antioxidant lycopene attenuated the adverse effects on fecundity, implying that oxidative stress was the cause of this phenotype. Pre-feeding with 6AN increased insecticide susceptibility in DDT resistant mosquitoes. These results indicate that oxidative state is delicate in mosquitoes, manipulation of NADPH pool may adversely affect fecundity and insecticide detoxification capacity. This knowledge can be exploited to develop novel vector control strategies targeting fecundity and insecticide resistance.
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21
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Ketoh GK, Ahadji-Dabla KM, Chabi J, Amoudji AD, Apetogbo GY, Awokou F, Glitho IA. Efficacy of two PBO long lasting insecticidal nets against natural populations of Anopheles gambiae s.l. in experimental huts, Kolokopé, Togo. PLoS One 2018; 13:e0192492. [PMID: 29995894 PMCID: PMC6040683 DOI: 10.1371/journal.pone.0192492] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 01/24/2018] [Indexed: 11/18/2022] Open
Abstract
LLINs containing an insecticide plus the synergist, piperonyl butoxide (PBO) have been designed for increased efficacy against pyrethroid-resistant malaria vectors. In this study, two LLINs with PBO, PermaNet® 3.0 and Olyset® Plus, and a pyrethroid-only LLIN, Yorkool®, were evaluated in experimental huts against a free-flying, wild population of Anopheles gambiae s.l. in Kolokopé, a cotton cultivated area of Togo. WHO susceptibility tube tests and subsequent molecular assays determine the An. gambiae s.l. populations to be resistant to pyrethroids and DDT with both target site kdr and metabolic resistance mechanisms involved in the resistance observed. Anopheles gambiae s.s. and An. coluzzi were present in sympatry though the kdr (L1014F) mutation was observed at a higher frequency in An. gambiae s.s. The experimental hut results showed that both PermaNet® 3.0 and Olyset® Plus nets induced similar levels of deterrence, exophily, and reduced blood feeding rate against wild An. gambiae s.l. in contrast to the pyrethroid only LLIN, Yorkool®. The proportion of wild An. gambiae s.l. killed by unwashed PermaNet® 3.0 was significantly higher than unwashed Olyset® Plus (corrected mortality 80.5% compared to 66.6%). Similar blood feeding inhibition rates were observed for unwashed PermaNet® 3.0 and Olyset® Plus; however, PermaNet® 3.0 washed 20 times demonstrated significantly higher blood feeding inhibition rate than Olyset® Plus washed 20 times (91.1% compared with 85.6% respectively). Yorkool® performed the worst for all the parameters evaluated. In an area of pyrethroid resistance of An. gambiae s.l involving kdr target site and metabolic resistance mechanisms, LLINs with PBO can provide additional protection in terms of reduction in blood feeding and increase in mosquito mortality compared to a pyrethroid-only net, and should be considered in malaria vector control strategies.
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Affiliation(s)
- Guillaume K. Ketoh
- Insect Pest and Insect Vector Management/Ecotoxicology, Unité de Recherche en Ecotoxicologie (URET), Laboratoire d’Entomologie Appliquée (LEA), Faculté des Sciences, Université de Lomé, Lomé, Togo
| | - Koffi M. Ahadji-Dabla
- Insect Pest and Insect Vector Management/Ecotoxicology, Unité de Recherche en Ecotoxicologie (URET), Laboratoire d’Entomologie Appliquée (LEA), Faculté des Sciences, Université de Lomé, Lomé, Togo
- * E-mail:
| | - Joseph Chabi
- Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Legon, Accra, Ghana
| | - Adjovi D. Amoudji
- Insect Pest and Insect Vector Management/Ecotoxicology, Unité de Recherche en Ecotoxicologie (URET), Laboratoire d’Entomologie Appliquée (LEA), Faculté des Sciences, Université de Lomé, Lomé, Togo
| | - Georges Y. Apetogbo
- Insect Pest and Insect Vector Management/Ecotoxicology, Unité de Recherche en Ecotoxicologie (URET), Laboratoire d’Entomologie Appliquée (LEA), Faculté des Sciences, Université de Lomé, Lomé, Togo
| | - Fantchè Awokou
- Programme National de Lutte contre le Paludisme (PNLP), Ministère de la Santé, Lomé, Togo
| | - Isabelle A. Glitho
- Insect Pest and Insect Vector Management/Ecotoxicology, Unité de Recherche en Ecotoxicologie (URET), Laboratoire d’Entomologie Appliquée (LEA), Faculté des Sciences, Université de Lomé, Lomé, Togo
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22
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Kuri-Morales PA, Correa-Morales F, González-Acosta C, Moreno-Garcia M, Santos-Luna R, Román-Pérez S, Salazar-Penagos F, Lombera-González M, Sánchez-Tejeda G, González-Roldán JF. Insecticide susceptibility status in Mexican populations of Stegomyia aegypti (= Aedes aegypti): a nationwide assessment. MEDICAL AND VETERINARY ENTOMOLOGY 2018; 32:162-174. [PMID: 29165810 DOI: 10.1111/mve.12281] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 08/22/2017] [Accepted: 10/18/2017] [Indexed: 06/07/2023]
Abstract
In Mexico, mosquito vector-borne diseases are of public health concern as a result of their impact on human morbidity and mortality. The use of insecticides against adult mosquitoes is one of the most common ways of controlling mosquito population densities. However, the use of these compounds has resulted in the development of insecticide resistance. The aim of this study was to estimate susceptibility to six pyrethroids, two carbamates and two organophosphates in Mexican populations of Stegomyia aegypti (Linnaeus, 1762) (= Aedes aegypti) (Diptera: Culicidae) mosquitoes. Bottle insecticide susceptibility tests, with 1 h exposure, were performed on adult mosquitoes from 75 localities across 28 states. At 30 min of exposure, the proportion of fallen mosquitoes was recorded. After 60 min of exposure, mosquitoes were recovered in non-treated containers and mortality was determined at 24 h after the set-up of the experiment. In general, the carbamate insecticides represented the most effective group in terms of the proportion of mosquitoes fallen at 30 min (72-100%) and 24-h mortality (97-100%). High and widespread resistance to pyrethroids Types I and II and, to a lesser extent, to organophosphates was observed. Insecticide susceptibility among and within states was highly variable.
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Affiliation(s)
| | - F Correa-Morales
- Centro Nacional de Programas Preventivos y Control de Enfermedades, Mexico City, Mexico
| | - C González-Acosta
- Centro Nacional de Programas Preventivos y Control de Enfermedades, Mexico City, Mexico
| | - M Moreno-Garcia
- Centro Nacional de Programas Preventivos y Control de Enfermedades, Mexico City, Mexico
- Unidad de Bioensayo, Centro Regional de Control de Vectores Panchimalco, Servicios de Salud de Morelos, Morelos, Mexico
| | - R Santos-Luna
- Instituto Nacional de Salud Pública, Cuernavaca, Morelos, Mexico
| | - S Román-Pérez
- Instituto Nacional de Salud Pública, Cuernavaca, Morelos, Mexico
| | | | | | - G Sánchez-Tejeda
- Centro Nacional de Programas Preventivos y Control de Enfermedades, Mexico City, Mexico
| | - J F González-Roldán
- Centro Nacional de Programas Preventivos y Control de Enfermedades, Mexico City, Mexico
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23
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Thiaw O, Doucouré S, Sougoufara S, Bouganali C, Konaté L, Diagne N, Faye O, Sokhna C. Investigating insecticide resistance and knock-down resistance (kdr) mutation in Dielmo, Senegal, an area under long lasting insecticidal-treated nets universal coverage for 10 years. Malar J 2018; 17:123. [PMID: 29566682 PMCID: PMC5863856 DOI: 10.1186/s12936-018-2276-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 03/15/2018] [Indexed: 11/10/2022] Open
Abstract
Background The use of insecticides, through indoor residual spraying and long-lasting insecticide-treated nets (LLINs), is essential to control malaria vectors. However, the sustainability of these tools is challenged by the spread of insecticide resistance in Anopheles mosquitoes. This study was conducted to assess the susceptibility to insecticides and to determine the resistance mechanisms in malaria vectors in Dielmo, a rural area of western Senegal where LLINs were introduced a decade ago. Methods CDC bottle bioassays were used to determine the susceptibility of 2–5 day-old unfed Anopheles gambiae s.l. females to alphacypermethrin (12.5 µg/bottle), deltamethrin (12.5 µg/bottle), etofenprox (12.5 µg/bottle), lambdacyhalothrin (12.5 µg/bottle), permethrin (21.5 µg/bottle), DDT (100 µg/bottle), bendiocarb (12.5 µg/bottle), pirimiphos-methyl (20 µg/bottle) and fenitrothion (50 µg/bottle). The involvement of glutathione-S-transferases (GSTs) in insecticide resistance was assessed using a synergist, etacrynic acid (EA, 80 µg/bottle). Polymerase chain reaction (PCR) was used to investigate the presence of ‘knock-down resistance (kdr)’ mutation and to identify sibling species within the An. gambiae complex. Results CDC bottle bioassays showed that mosquitoes were fully susceptible to lambdacyhalothrin, bendiocarb and fenitrothion. Overall, mortality rates of 97, 94.6, 93.5, 92.1, and 90.1% were, respectively, observed for permethrin, deltamethrin, pirimiphos-methyl, etofenprox and alphacypermethrin. Resistance to DDT was observed, with a mortality rate of 62%. The use of EA significantly improved the susceptibility of An. gambiae s.l. to DDT by inhibiting GSTs (p = 0.03). PCR revealed that Anopheles arabiensis was the predominant species (91.3%; IC 95 86.6–94%) within An. gambiae complex from Dielmo, followed by Anopheles coluzzii (5.4%; IC 95 2.7–8.1%) and Anopheles gambiae s.s. (3.3%; IC 95 0.6–5.9%). Both 1014F and 1014S alleles were found in An. arabiensis population with frequencies of 0.08 and 0.361, respectively, and 0.233 and 0.133, respectively in An. coluzzii. In An. gambiae s.s. population, only kdr L1014F mutation was detected, with a frequency of 0.167. It was observed that some individual mosquitoes carried both alleles, with 19 specimens recorded for An. arabiensis and 2 for An. coluzzii. The presence of L1014F and L1014S alleles were not associated with resistance to pyrethroids and DDT in An. arabiensis. Conclusions The co-occurrence of 1014F and 1014S alleles and the probable involvement of GSTs enzymes in insecticide resistance in An. gambiae s.l. should prompt the local vector programme to implement non-pyrethroid/DDT insecticides alternatives.
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Affiliation(s)
- Omar Thiaw
- UMR Vecteurs-Infections Tropicales et Méditerranéennes (VITROME), Campus International UCAD-IRD Hann Maristes, Dakar, Senegal.,Laboratoire d'Ecologie Vectorielle et Parasitaire (LEVP), Faculté des Sciences et Techniques (FST), Université Cheikh Anta Diop (UCAD), Dakar, Senegal
| | - Souleymane Doucouré
- UMR Vecteurs-Infections Tropicales et Méditerranéennes (VITROME), Campus International UCAD-IRD Hann Maristes, Dakar, Senegal
| | - Seynabou Sougoufara
- UMR Vecteurs-Infections Tropicales et Méditerranéennes (VITROME), Campus International UCAD-IRD Hann Maristes, Dakar, Senegal
| | - Charles Bouganali
- UMR Vecteurs-Infections Tropicales et Méditerranéennes (VITROME), Campus International UCAD-IRD Hann Maristes, Dakar, Senegal
| | - Lassana Konaté
- Laboratoire d'Ecologie Vectorielle et Parasitaire (LEVP), Faculté des Sciences et Techniques (FST), Université Cheikh Anta Diop (UCAD), Dakar, Senegal
| | - Nafissatou Diagne
- UMR Vecteurs-Infections Tropicales et Méditerranéennes (VITROME), Campus International UCAD-IRD Hann Maristes, Dakar, Senegal
| | - Ousmane Faye
- Laboratoire d'Ecologie Vectorielle et Parasitaire (LEVP), Faculté des Sciences et Techniques (FST), Université Cheikh Anta Diop (UCAD), Dakar, Senegal
| | - Cheikh Sokhna
- UMR Vecteurs-Infections Tropicales et Méditerranéennes (VITROME), Campus International UCAD-IRD Hann Maristes, Dakar, Senegal.
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Messenger LA, Shililu J, Irish SR, Anshebo GY, Tesfaye AG, Ye-Ebiyo Y, Chibsa S, Dengela D, Dissanayake G, Kebede E, Zemene E, Asale A, Yohannes M, Taffese HS, George K, Fornadel C, Seyoum A, Wirtz RA, Yewhalaw D. Insecticide resistance in Anopheles arabiensis from Ethiopia (2012-2016): a nationwide study for insecticide resistance monitoring. Malar J 2017; 16:469. [PMID: 29151024 PMCID: PMC5694167 DOI: 10.1186/s12936-017-2115-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 11/10/2017] [Indexed: 11/27/2022] Open
Abstract
Background Indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs) remain the cornerstones of malaria vector control. However, the development of insecticide resistance and its implications for operational failure of preventative strategies are of concern. The aim of this study was to characterize insecticide resistance among Anopheles arabiensis populations in Ethiopia and describe temporal and spatial patterns of resistance between 2012 and 2016. Methods Between 2012 and 2016, resistance status of An. arabiensis was assessed annually during the long rainy seasons in study sites from seven of the nine regions in Ethiopia. Insecticide resistance levels were measured with WHO susceptibility tests and CDC bottle bioassays using insecticides from four chemical classes (organochlorines, pyrethroids, organophosphates and carbamates), with minor variations in insecticides tested and assays conducted between years. In selected sites, CDC synergist assays were performed by pre-exposing mosquitoes to piperonyl butoxide (PBO). In 2015 and 2016, mosquitoes from DDT and deltamethrin bioassays were randomly selected, identified to species-level and screened for knockdown resistance (kdr) by PCR. Results Intense resistance to DDT and pyrethroids was pervasive across Ethiopia, consistent with historic use of DDT for IRS and concomitant increases in insecticide-treated net coverage over the last 15 years. Longitudinal resistance trends to malathion, bendiocarb, propoxur and pirimiphos-methyl corresponded to shifts in the national insecticide policy. By 2016, resistance to the latter two insecticides had emerged, with the potential to jeopardize future long-term effectiveness of vector control activities in these areas. Between 2015 and 2016, the West African (L1014F) kdr allele was detected in 74.1% (n = 686/926) of specimens, with frequencies ranging from 31 to 100% and 33 to 100% in survivors from DDT and deltamethrin bioassays, respectively. Restoration of mosquito susceptibility, following pre-exposure to PBO, along with a lack of association between kdr allele frequency and An. arabiensis mortality rate, both indicate metabolic and target-site mutation mechanisms are contributing to insecticide resistance. Conclusions Data generated by this study will strengthen the National Malaria Control Programme’s insecticide resistance management strategy to safeguard continued efficacy of IRS and other malaria control methods in Ethiopia. Electronic supplementary material The online version of this article (10.1186/s12936-017-2115-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Louisa A Messenger
- Entomology Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA, 30329-4027, USA.
| | - Josephat Shililu
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, Gerji Road, Sami Building, 1st Floor, Addis Ababa, Ethiopia
| | - Seth R Irish
- Entomology Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA, 30329-4027, USA
| | - Gedeon Yohannes Anshebo
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, Gerji Road, Sami Building, 1st Floor, Addis Ababa, Ethiopia
| | - Alemayehu Getachew Tesfaye
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, Gerji Road, Sami Building, 1st Floor, Addis Ababa, Ethiopia
| | - Yemane Ye-Ebiyo
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, Gerji Road, Sami Building, 1st Floor, Addis Ababa, Ethiopia
| | - Sheleme Chibsa
- U.S. Agency for International Development (USAID), Entoto Street, Addis Ababa, Ethiopia
| | - Dereje Dengela
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, 4550 Montgomery Ave., Suite 800 North, Bethesda, MD, 20814, USA
| | | | - Estifanos Kebede
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Endalew Zemene
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Abebe Asale
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Mekonnen Yohannes
- Medical and Entomology Unit, Institute of Bio-Medical Sciences, College of Health Sciences, Mekelle University, Mek'ele, Ethiopia
| | - Hiwot Solomon Taffese
- National Malaria Control Programne, Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Kristen George
- President's Malaria Initiative, United States Agency for International Development, Bureau for Global Health, Office of Infectious Disease, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Christen Fornadel
- President's Malaria Initiative, United States Agency for International Development, Bureau for Global Health, Office of Infectious Disease, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Aklilu Seyoum
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, 4550 Montgomery Ave., Suite 800 North, Bethesda, MD, 20814, USA
| | - Robert A Wirtz
- Entomology Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA, 30329-4027, USA
| | - Delenasaw Yewhalaw
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia.,Department of Medical Laboratory Sciences and Pathology, College of Health Sciences, Jimma University, Jimma, Ethiopia
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Rakotoson JD, Fornadel CM, Belemvire A, Norris LC, George K, Caranci A, Lucas B, Dengela D. Insecticide resistance status of three malaria vectors, Anopheles gambiae (s.l.), An. funestus and An. mascarensis, from the south, central and east coasts of Madagascar. Parasit Vectors 2017; 10:396. [PMID: 28835269 PMCID: PMC5569519 DOI: 10.1186/s13071-017-2336-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 08/16/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Insecticide-based vector control, which comprises use of insecticide-treated bed nets (ITNs) and indoor residual spraying (IRS), is the key method to malaria control in Madagascar. However, its effectiveness is threatened as vectors become resistant to insecticides. This study investigated the resistance status of malaria vectors in Madagascar to various insecticides recommended for use in ITNs and/or IRS. METHODS WHO tube and CDC bottle bioassays were performed on populations of Anopheles gambiae (s.l.), An. funestus and An. mascarensis. Adult female An. gambiae (s.l.) mosquitoes reared from field-collected larvae and pupae were tested for their resistance to DDT, permethrin, deltamethrin, alpha-cypermethrin, lambda-cyhalothrin, bendiocarb and pirimiphos-methyl. Resting An. funestus and An. mascarensis female mosquitoes collected from unsprayed surfaces were tested against permethrin, deltamethrin and pirimiphos-methyl. The effect on insecticide resistance of pre-exposure to the synergists piperonyl-butoxide (PBO) and S,S,S-tributyl phosphorotrithioate (DEF) also was assessed. Molecular analyses were done to identify species and determine the presence of knock-down resistance (kdr) and acetylcholinesterase resistance (ace-1 R ) gene mutations. RESULTS Anopheles funestus and An. mascarensis were fully susceptible to permethrin, deltamethrin and pirimiphos-methyl. Anopheles gambiae (s.l.) was fully susceptible to bendiocarb and pirimiphos-methyl. Among the 17 An. gambiae (s.l.) populations tested for deltamethrin, no confirmed resistance was recorded, but suspected resistance was observed in two sites. Anopheles gambiae (s.l.) was resistant to permethrin in four out of 18 sites (mortality 68-89%) and to alpha-cypermethrin (89% mortality) and lambda-cyhalothrin (80% and 85%) in one of 17 sites, using one or both assay methods. Pre-exposure to PBO restored full susceptibility to all pyrethroids tested except in one site where only partial restoration to permethrin was observed. DEF fully suppressed resistance to deltamethrin and alpha-cypermethrin, while it partially restored susceptibility to permethrin in two of the three sites. Molecular analysis data suggest absence of kdr and ace-1 R gene mutations. CONCLUSION This study suggests involvement of detoxifying enzymes in the phenotypic resistance of An. gambiae (s.l.) to pyrethroids. The absence of resistance in An. funestus and An. mascarensis to pirimiphos-methyl and pyrethroids and in An. gambiae (s.l.) to carbamates and organophosphates presents greater opportunity for managing resistance in Madagascar.
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Affiliation(s)
- Jean-Desire Rakotoson
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, Antananarivo, Madagascar
| | - Christen M Fornadel
- U.S. President's Malaria Initiative, United States Agency for International Development, Bureau for Global Health, Office of Infectious Disease, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Allison Belemvire
- U.S. President's Malaria Initiative, United States Agency for International Development, Bureau for Global Health, Office of Infectious Disease, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Laura C Norris
- U.S. President's Malaria Initiative, United States Agency for International Development, Bureau for Global Health, Office of Infectious Disease, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Kristen George
- U.S. President's Malaria Initiative, United States Agency for International Development, Bureau for Global Health, Office of Infectious Disease, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Angela Caranci
- U.S. President's Malaria Initiative, United States Agency for International Development, Bureau for Global Health, Office of Infectious Disease, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Bradford Lucas
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, 4550 Montgomery Ave, Suite 800 North, Bethesda, MD, 20814, USA
| | - Dereje Dengela
- President's Malaria Initiative Africa Indoor Residual Spraying Project, Abt Associates, 4550 Montgomery Ave, Suite 800 North, Bethesda, MD, 20814, USA.
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Rodríguez MM, Crespo A, Hurtado D, Fuentes I, Rey J, Bisset JA. Diagnostic Doses of Insecticides for Adult Aedes aegypti to Assess Insecticide Resistance in Cuba. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2017; 33:142-144. [PMID: 28590216 DOI: 10.2987/16-6593.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The objective of this study was to determine diagnostic doses (DDs) of 5 insecticides for the Rockefeller susceptible strain of Aedes aegypti , using the Centers for Disease Control and Prevention (CDC) bottle bioassay as a tool for monitoring insecticide resistance in the Cuban vector control program. The 30-min DD values determined in this study were 13.5 μg/ml, 6.5 μg/ml, 6 μg/ml, 90.0 μg/ml, and 15.0 μg/ml for cypermethrin, deltamethrin, lambda-cyhalothrin, chlorpyrifos, and propoxur, respectively. To compare the reliability of CDC bottle bioassay with the World Health Organization susceptible test, 3 insecticide-resistant strains were evaluated for deltamethrin and lambda-cyhalothrin. Results showed that the bottles can be used effectively from 21 to 25 days after treatment and reused up to 4 times, depending on the storage time. The CDC bottle bioassay is an effective tool to assess insecticide resistance in field populations of Ae. aegypti in Cuba and can be incorporated into vector management programs using the diagnostic doses determined in this study.
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Guo Q, Huang Y, Zou F, Liu B, Tian M, Ye W, Guo J, Sun X, Zhou D, Sun Y, Ma L, Shen B, Zhu C. The role of miR-2∼13∼71 cluster in resistance to deltamethrin in Culex pipiens pallens. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2017; 84:15-22. [PMID: 28342977 DOI: 10.1016/j.ibmb.2017.03.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 02/24/2017] [Accepted: 03/21/2017] [Indexed: 06/06/2023]
Abstract
Excessive and continuous application of deltamethrin has resulted in the development of deltamethrin resistance among mosquitoes, which becomes a major obstacle for mosquito control. In a previous study, differentially expressed miRNAs between deltamethrin-susceptible (DS) strain and deltamethrin-resistant (DR) strain using illumina sequencing in Culex pipiens pallens were identified. In this study, we applied RNAi and the Centers for Disease Control and Prevention (CDC) bottle bioassay to investigate the relationship between miR-2∼13∼71 cluster (miR-2, miR-13 and miR-71) and deltamethrin resistance. We used quantitative real-time PCR (qRT-PCR) to measure expression levels of miR-2∼13∼71 clusters. MiR-2∼13∼71 cluster was down regulated in adult female mosquitoes from the DR strain and played important roles in deltamethrin resistance through regulating target genes, CYP9J35 and CYP325BG3. Knocking down CYP9J35 and CYP325BG3 resulted in decreased mortality of DR mosquitoes. This study provides the first evidence that miRNA clusters are associated with deltamethrin resistance in mosquitoes. Moreover, we investigated the regulatory networks formed between miR-2∼13∼71 cluster and its target genes, which provide a better understanding of the mechanism involved in deltamethrin resistance.
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Affiliation(s)
- Qin Guo
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China
| | - Yun Huang
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China
| | - Feifei Zou
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China; Microbiology and Immunology Department, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210023, PR China
| | - Bingqian Liu
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China; Department of Clinical Laboratory, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, PR China
| | - Mengmeng Tian
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China
| | - Wenyun Ye
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China
| | - Juxin Guo
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China
| | - Xueli Sun
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China
| | - Dan Zhou
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China
| | - Yan Sun
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China
| | - Lei Ma
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China
| | - Bo Shen
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China.
| | - Changliang Zhu
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, 211166, PR China; Jiangsu Province Key Laboratory of Modern Pathogen Biology, Nanjing, Jiangsu, 211166, PR China.
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El Zayyat EA, Soliman MI, Elleboudy NA, Ofaa SE. Bioefficacy of Some Egyptian Aromatic Plants on Culex pipiens (Diptera: Culicidae) Adults and Larvae. J Arthropod Borne Dis 2017; 11:147-155. [PMID: 29026862 PMCID: PMC5629297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 12/28/2015] [Indexed: 10/31/2022] Open
Abstract
BACKGROUND Protecting the environment from chemical hazards of synthetic insecticides along with offering of new breeding areas for vectors by urbanization indicate the trial of natural insecticides. METHODS The acetone extracts of Anethum graveolens, Ocimum basilicum and Thymus vulgaris were tested for their insecticidal effect on Culex pipiens adults and larvae in different concentrations depending on the technique used. RESULTS The extracts were significantly effective in all models used with basil being the best in all tested three techniques (LC50= 0.064) in larval feeding, (LC50= 0.330) in CDC bottle assay and (LC50= 13.148) in adults feeding (P< 0.05). CONCLUSION The results recommend the eco-friendly studied extracts as candidates for controlling Cx. pipiens the lymphatic filariasis vector.
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Affiliation(s)
- Elham A El Zayyat
- Parasitology Department, Faculty of Medicine, Ain-Shams University, Cairo, Egypt
| | | | - Noha A Elleboudy
- Parasitology Department, Faculty of Medicine, Ain-Shams University, Cairo, Egypt,Corresponding author: Dr Noha A. Elleboudy, E-mail:
| | - Shaimaa E Ofaa
- Parasitology Department, Faculty of Medicine, Ain-Shams University, Cairo, Egypt
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Susceptibility of Anopheles gambiae to insecticides used for malaria vector control in Rwanda. Malar J 2016; 15:582. [PMID: 27905919 PMCID: PMC5134262 DOI: 10.1186/s12936-016-1618-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 11/15/2016] [Indexed: 11/10/2022] Open
Abstract
Background The widespread emergence of resistance to pyrethroids is a major threat to the gains made in malaria control. To monitor the presence and possible emergence of resistance against a variety of insecticides used for malaria control in Rwanda, nationwide insecticide resistance surveys were conducted in 2011 and 2013. Methods Larvae of Anopheles gambiae sensu lato mosquitoes were collected in 12 sentinel sites throughout Rwanda. These were reared to adults and analysed for knock-down and mortality using WHO insecticide test papers with standard diagnostic doses of the recommended insecticides. A sub-sample of tested specimens was analysed for the presence of knockdown resistance (kdr) mutations. Results A total of 14,311 mosquitoes were tested and from a sample of 1406 specimens, 1165 (82.9%) were identified as Anopheles arabiensis and 241 (17.1%) as Anopheles gambiae sensu stricto. Mortality results indicated a significant increase in resistance to lambda-cyhalothrin from 2011 to 2013 in 83% of the sites, permethrin in 25% of the sites, deltamethrin in 25% of the sites and DDT in 50% of the sites. Mosquitoes from 83% of the sites showed full susceptibility to bendiocarb and 17% of sites were suspected to harbour resistance that requires further confirmation. No resistance was observed to fenitrothion in all study sites during the entire survey. The kdr genotype results in An. gambiae s.s. showed that 67 (50%) possessed susceptibility (SS) alleles, while 35 (26.1%) and 32 (23.9%) mosquitoes had heterozygous (RS) and homozygous (RR) alleles, respectively. Of the 591 An. arabiensis genotyped, 425 (71.9%) possessed homozygous (SS) alleles while 158 (26.7%) and 8 (1.4%) had heterozygous (RS) and homozygous (RR) alleles, respectively. Metabolic resistance involving oxidase enzymes was also detected using the synergist PBO. Conclusion This is the first nationwide study of insecticide resistance in malaria vectors in Rwanda. It shows the gradual increase of insecticide resistance to pyrethroids (lambda-cyhalothrin, deltamethrin, permethrin) and organochlorines (DDT) and the large presence of target site insensitivity. The results demonstrate the need for Rwanda to expand monitoring for insecticide resistance including further metabolic resistance testing and implement an insecticide resistance management strategy to sustain the gains made in malaria control.
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Karakuş M, Sarıkaya Y, Oğuz G, Doğan M, Ergan G, Günay F, Kasap ÖE, Özbel Y, Alten B. Assessment of diagnostic doses for widely used synthetic pyrethroids (Deltamethrin & Permethrin) in an endemic focus of leishmaniasis in Turkey. Parasit Vectors 2016; 9:526. [PMID: 27688146 PMCID: PMC5043626 DOI: 10.1186/s13071-016-1812-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 09/22/2016] [Indexed: 11/17/2022] Open
Abstract
Background Leishmania is a group of parasitic flagellated protozoons, which are transmitted by female sand flies and produces health problems in humans and also in wild and domestic animals. So far, 25 Phlebotomus and 4 Sergentomyia species were recorded in Turkey including proven or possible vectors of Leishmania spp. As no single insecticide susceptibility test was conducted targeting the sand flies in Turkey, we aimed to determine the diagnostic dose against two commonly used synthetic pyrethroids (deltamethrin and permethrin) in a hyperendemic area for leishmaniasis. Methods Sand flies were collected from villages of Adana in 2–4 September 2013 using Centers for Disease Control and Prevention (CDC) light traps and transferred to the laboratory. The World Health Organisation tube test method was conducted using self-prepared filter papers with different concentrations. In order to determine the diagnostic dose, lethal doses (LD) were calculated by EPA Probit Analysis. Sand flies used in the experiments were dissected, mounted and identified. Results For the lowest (0.025 %) and highest dose of permethrin (0.5 %), the mortality rate was recorded as 52.6 % and 100 % by the end of 24-h period and the diagnostic dose was recorded as 0.36 %. The mortality rate for lowest (0.0025 %) and highest (0.05 %) doses of deltamethrin was recorded as 54.8 % and 100 %. The diagnostic dose of deltamethrin was determined as 0.9 %. Conclusion An insecticide susceptibility study was conducted in Turkey for the first time and effective doses were determined by calculating the LDs. According to presented results, the wild population of sand flies collected from a hyper-endemic region of Adana Province is still susceptible to deltamethrin and permethrin.
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Affiliation(s)
- Mehmet Karakuş
- Department of Parasitology, Faculty of Medicine, Ege University, Bornova, İzmir, Turkey.
| | - Yasemen Sarıkaya
- Department of Biology, Ecology Division, HUESRL-VERG laboratories, Hacettepe University, Ankara, Turkey
| | - Gizem Oğuz
- Department of Biology, Ecology Division, HUESRL-VERG laboratories, Hacettepe University, Ankara, Turkey
| | - Mert Doğan
- Department of Biology, Ecology Division, HUESRL-VERG laboratories, Hacettepe University, Ankara, Turkey
| | - Gökhan Ergan
- Department of Biology, Ecology Division, HUESRL-VERG laboratories, Hacettepe University, Ankara, Turkey
| | - Filiz Günay
- Department of Biology, Ecology Division, HUESRL-VERG laboratories, Hacettepe University, Ankara, Turkey
| | - Özge Erişöz Kasap
- Department of Biology, Ecology Division, HUESRL-VERG laboratories, Hacettepe University, Ankara, Turkey
| | - Yusuf Özbel
- Department of Parasitology, Faculty of Medicine, Ege University, Bornova, İzmir, Turkey
| | - Bülent Alten
- Department of Biology, Ecology Division, HUESRL-VERG laboratories, Hacettepe University, Ankara, Turkey
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Ma K, Li X, Hu H, Zhou D, Sun Y, Ma L, Zhu C, Shen B. Pyrethroid-resistance is modulated by miR-92a by targeting CpCPR4 in Culex pipiens pallens. Comp Biochem Physiol B Biochem Mol Biol 2016; 203:20-24. [PMID: 27627779 DOI: 10.1016/j.cbpb.2016.09.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 08/30/2016] [Accepted: 09/08/2016] [Indexed: 11/26/2022]
Abstract
The wide use of pyrethroids has resulted in the emergence and spread of resistance in mosquito populations, which represent a major obstacle in the struggle against vector-borne diseases. Resistance to pyrethroids is a complex genetic phenomenon attributed by polygenetic inheritance. We previously have sequenced and analyzed the miRNA profiles of Culex pipiens pallens. MiR-92a was found to be overexpressed in a deltamethrin-resistant (DR) strain. The association of miR-92a with pyrethroid-resistance was investigated by quantitative reverse transcription PCR (qRT-PCR). Expression levels of miR-92a were 2.72-fold higher in the DR strain than in the deltamethrin-susceptible (DS) strain. Bioinformatic analysis suggested that CpCPR4, a mosquito cuticle gene, is the target of miR-92a. Dual luciferase reporter assays further confirmed that CpCPR4 is modulated by miR-92a through binding to a specific target site in the 3' untranslated region (3' UTR). Microinjection of the miR-92a inhibitor upregulated CpCPR4 expression levels, leading to an increase in the susceptibility of the DR strain in the Centers for Disease Control and Prevention (CDC) bottle bioassay (a surveillance tool for detecting resistance to insecticides in vector populations). Taken together, our findings indicate that miR-92a regulates pyrethroid-resistance through its interaction with CpCPR4.
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Affiliation(s)
- Kai Ma
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu 210029, PR China
| | - Xixi Li
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu 210029, PR China
| | - Hongxia Hu
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu 210029, PR China
| | - Dan Zhou
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu 210029, PR China
| | - Yan Sun
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu 210029, PR China
| | - Lei Ma
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu 210029, PR China
| | - Changliang Zhu
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu 210029, PR China
| | - Bo Shen
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu 210029, PR China.
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VanDusen AE, Richards SL, Balanay JAG. Evaluation of bifenthrin barrier spray on foliage in a suburban eastern North Carolina neighborhood. PEST MANAGEMENT SCIENCE 2016; 72:1004-1012. [PMID: 26174607 DOI: 10.1002/ps.4081] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 06/23/2015] [Accepted: 07/09/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND Mosquitoes can transmit pathogens through blood feeding. Mosquito control programs conduct surveillance and source reduction, treat mosquito oviposition sites and spray adulticides to protect public health. In some areas, homeowners may contract with private mosquito control companies to address mosquito-related issues. RESULTS We evaluated the efficacy of barrier sprays by comparing weekly host-seeking mosquito abundance at treatment and control properties in a residential neighborhood. The chemical concentration of bifenthrin residue on foliage was quantified, and field-collected mosquitoes, primarily Aedes albopictus, were tested for bifenthrin resistance using bottle bioassays. Mosquito abundance at treatment properties was significantly (P < 0.05) lower than at control properties. Quantities of bifenthrin detected on foliage from treatment properties was not correlated with mosquito abundance. No bifenthrin resistance was detected in captured mosquitoes. CONCLUSION Based on the rate of application, we expected that chemical analysis of bifenthrin residue would show similar concentrations of bifenthrin on foliage in treatment areas. Although mosquitoes were not bifenthrin resistant, further studies are needed to evaluate the extent to which resistance changes over time with repeated applications. Findings from this study provide insight into control methods commonly used by mosquito control companies and could potentially be used to guide future mosquito management strategies.
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Denlinger DS, Creswell JA, Anderson JL, Reese CK, Bernhardt SA. Diagnostic doses and times for Phlebotomus papatasi and Lutzomyia longipalpis sand flies (Diptera: Psychodidae: Phlebotominae) using the CDC bottle bioassay to assess insecticide resistance. Parasit Vectors 2016; 9:212. [PMID: 27083417 PMCID: PMC4833940 DOI: 10.1186/s13071-016-1496-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 04/05/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Insecticide resistance to synthetic chemical insecticides is a worldwide concern in phlebotomine sand flies (Diptera: Psychodidae), the vectors of Leishmania spp. parasites. The CDC bottle bioassay assesses resistance by testing populations against verified diagnostic doses and diagnostic times for an insecticide, but the assay has been used limitedly with sand flies. The objective of this study was to determine diagnostic doses and diagnostic times for laboratory Lutzomyia longipalpis (Lutz & Nieva) and Phlebotomus papatasi (Scopoli) to ten insecticides, including pyrethroids, organophosphates, carbamates, and DDT, that are used worldwide to control vectors. METHODS Bioassays were conducted in 1,000-ml glass bottles each containing 10-25 sand flies from laboratory colonies of L. longipalpis or P. papatasi. Four pyrethroids, three organophosphates, two carbamates and one organochlorine, were evaluated. A series of concentrations were tested for each insecticide, and four replicates were conducted for each concentration. Diagnostic doses were determined only during the exposure bioassay for the organophosphates and carbamates. For the pyrethroids and DDT, diagnostic doses were determined for both the exposure bioassay and after a 24-hour recovery period. RESULTS Both species are highly susceptible to the carbamates as their diagnostic doses are under 7.0 μg/ml. Both species are also highly susceptible to DDT during the exposure assay as their diagnostic doses are 7.5 μg/ml, yet their diagnostic doses for the 24-h recovery period are 650.0 μg/ml for Lu. longipalpis and 470.0 μg/ml for P. papatasi. CONCLUSIONS Diagnostic doses and diagnostic times can now be incorporated into vector management programs that use the CDC bottle bioassay to assess insecticide resistance in field populations of Lu. longipalpis and P. papatasi. These findings provide initial starting points for determining diagnostic doses and diagnostic times for other sand fly vector species and wild populations using the CDC bottle bioassay.
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Affiliation(s)
| | | | | | - Conor K Reese
- Department of Biology, Utah State University, Logan, Utah, USA
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El Zayyat EA, Soliman MI, Elleboudy NA, Ofaa SE. Musca domestica laboratory susceptibility to three ethnobotanical culinary plants. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:15844-52. [PMID: 26036589 DOI: 10.1007/s11356-015-4796-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 05/27/2015] [Indexed: 05/06/2023]
Abstract
Throughout history, synanthropic Musca domestica had remained a worldwide problem whenever poor sanitation and bad hygienic conditions exists. Houseflies growing resistance to chemical insecticides are a rising environmental problem that necessitates search for alternatives. Mentha cervina, Ocimum basilicum, and Coriandrum sativum were tested for bioactivity on M. domestica adults and larvae. They are culinary Mediterranean plants. In adulticidal bioassay, using both CDC bottles and fumigation techniques, basil was the most effective extract with LC50 1.074 and 34.996 g/L, respectively. Concerning larvicidal bioassay by fumigation technique, coriander had the highest toxicity index with LC50 29.521 g/L. In both dipping and feeding technique, basil had the highest toxicity with LC50 32.643 and 0.749 g/L, respectively. Basil showed the highest toxicity results in four out of the five models tested followed by coriander then mint; this result highlights the potentiality of basil as a green insecticide in management of flies and opens new insight in the industrialization of basil-based fly control products.
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Affiliation(s)
- Elham A El Zayyat
- Parasitology Department, Faculty of Medicine, Ain-Shams University, Abbasiya, Cairo, Egypt
| | | | - Noha A Elleboudy
- Parasitology Department, Faculty of Medicine, Ain-Shams University, Abbasiya, Cairo, Egypt.
| | - Shaimaa E Ofaa
- Parasitology Department, Faculty of Medicine, Ain-Shams University, Abbasiya, Cairo, Egypt
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Denlinger DS, Lozano-Fuentes S, Lawyer PG, Black WC, Bernhardt SA. Assessing Insecticide Susceptibility of Laboratory Lutzomyia longipalpis and Phlebotomus papatasi Sand Flies (Diptera: Psychodidae: Phlebotominae). JOURNAL OF MEDICAL ENTOMOLOGY 2015; 52:1003-12. [PMID: 26336231 PMCID: PMC4574604 DOI: 10.1093/jme/tjv091] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 06/17/2015] [Indexed: 05/26/2023]
Abstract
Chemical insecticides are effective for controlling Lutzomyia and Phlebotomus sand fly (Diptera: Psychodidae) vectors of Leishmania parasites. However, repeated use of certain insecticides has led to tolerance and resistance. The objective of this study was to determine lethal concentrations (LCs) and lethal exposure times (LTs) to assess levels of susceptibility of laboratory Lutzomyia longipalpis (Lutz and Nieva) and Phlebotomus papatasi (Scopoli) to 10 insecticides using a modified version of the World Health Organization (WHO) exposure kit assay and Centers for Disease Control and Prevention (CDC) bottle bioassay. Sand flies were exposed to insecticides coated on the interior of 0.5-gallon and 1,000-ml glass bottles. Following exposure, the flies were allowed to recover for 24 h, after which mortality was recorded. From dose-response survival curves for L. longipalpis and P. papatasi generated with the QCal software, LCs causing 50, 90, and 95% mortality were determined for each insecticide. The LCs and LTs from this study will be useful as baseline reference points for future studies using the CDC bottle bioassays to assess insecticide susceptibility of sand fly populations in the field. There is a need for a larger repository of sand fly insecticide susceptibility data from the CDC bottle bioassays, including a range of LCs and LTs for more sand fly species with more insecticides. Such a repository would be a valuable tool for vector management.
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Affiliation(s)
| | - Saul Lozano-Fuentes
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, Saul
| | - Phillip G Lawyer
- Laboratory of Parasitic Diseases, Intracellular Parasite Biology Section, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
| | - William C Black
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, Saul
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Owusu HF, Jančáryová D, Malone D, Müller P. Comparability between insecticide resistance bioassays for mosquito vectors: time to review current methodology? Parasit Vectors 2015; 8:357. [PMID: 26148484 PMCID: PMC4492098 DOI: 10.1186/s13071-015-0971-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 06/30/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Insecticides play an integral role in the control of mosquito-borne diseases. With resistance to insecticides on the rise, surveillance of the target population for optimal choice of insecticides is a necessity. The Centers for Disease Control and Prevention (CDC) bottle assay and the World Health Organization (WHO) susceptibility test are the most frequently used methods in insecticide resistance monitoring. However, the two bioassays differ in terms of insecticide delivery and how insecticide susceptibility is measured. To evaluate how equivalent data from the two assays are, we compared the two methods side-by-side. METHODS We did a literature search from 1998 to December 2014 to identify publications that performed both assays on the same mosquito population and compared the results. We then tested the WHO and CDC bioassays on laboratory strains of Aedes aegypti, Anopheles stephensi, An. gambiae and An. arabiensis with different insecticide resistance levels against permethrin, λ-cyhalothrin, DDT, bendiocarb and malathion. In addition, we also measured the relationship between time-to-knockdown and 24 h mortality. RESULTS Both published data and results from the present laboratory experiments showed heterogeneity in the comparability of the two bioassays. Following their standard procedures, the two assays showed poor agreement in detecting resistance at the WHO cut-off mark of 90% (Cohen's κ = 0.06). There was better agreement when 24 h mortality was recorded in the CDC bottle assay and compared with that of the WHO susceptibility test (Cohen's κ = 0.5148). Time-to-knockdown was shown to be an unreliable predictor of 24 h mortality. CONCLUSION Even though the two assays can detect insecticide resistance, they may not be used interchangeably. While the diagnostic dose in the WHO susceptibility test does not allow for detecting shifts at low or extreme resistance levels, time-to-knockdown measured in the CDC bottle assay is a poor predictor of 24 h mortality. Therefore, dose-response assays could provide the most flexibility. New standardized bioassays are needed that produce consistent dose-response measurements with a minimal number of mosquitoes.
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Affiliation(s)
- Henry F Owusu
- Epidemiology and Public Health Department, Swiss Tropical and Public Health Institute, Socinstrasse 57, PO Box, CH-4002, Basel, Switzerland.
- University of Basel, Petersplatz 1, CH-2003, Basel, Switzerland.
| | - Danica Jančáryová
- Epidemiology and Public Health Department, Swiss Tropical and Public Health Institute, Socinstrasse 57, PO Box, CH-4002, Basel, Switzerland.
- University of Basel, Petersplatz 1, CH-2003, Basel, Switzerland.
| | - David Malone
- Innovative Vector Control Consortium, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Pie Müller
- Epidemiology and Public Health Department, Swiss Tropical and Public Health Institute, Socinstrasse 57, PO Box, CH-4002, Basel, Switzerland.
- University of Basel, Petersplatz 1, CH-2003, Basel, Switzerland.
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Saddler A, Burda PC, Koella JC. Resisting infection by Plasmodium berghei increases the sensitivity of the malaria vector Anopheles gambiae to DDT. Malar J 2015; 14:134. [PMID: 25888982 PMCID: PMC4379605 DOI: 10.1186/s12936-015-0646-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 03/08/2015] [Indexed: 01/25/2023] Open
Abstract
Background The evolution of insecticide resistance threatens current malaria control methods, which rely heavily on chemical insecticides. The magnitude of the threat will be determined by the phenotypic expression of resistance in those mosquitoes that can transmit malaria. These differ from the majority of the mosquito population in two main ways; they carry sporozoites (the infectious stage of the Plasmodium parasite) and they are relatively old, as they need to survive the development period of the malaria parasite. This study examines the effects of infection by Plasmodium berghei and of mosquito age on the sensitivity to DDT in a DDT-resistant strain of Anopheles gambiae. Methods DDT-resistant Anopheles gambiae (ZANU) mosquitoes received a blood meal from either a mouse infected with Plasmodium berghei or an uninfected mouse. 10 and 19 days post blood meal the mosquitoes were exposed to 2%, 1% or 0% DDT using WHO test kits. 24 hrs after exposure, mortality and Plasmodium infection status of the mosquitoes were recorded. Results Sensitivity to DDT increased with the mosquitoes’ age and was higher in mosquitoes that had fed on Plasmodium-infected mice than in those that had not been exposed to the parasite. The latter effect was mainly due to the high sensitivity of mosquitoes that had fed on an infected mouse but were not themselves infected, while the sensitivity to DDT was only slightly higher in mosquitoes infected by Plasmodium than in those that had fed on an uninfected mouse. Conclusions The observed pattern indicates a cost of parasite-resistance. It suggests that, in addition to the detrimental effect of insecticide-resistance on control, the continued use of insecticides in a population of insecticide-resistant mosquitoes could select mosquitoes to be more susceptible to Plasmodium infection, thus further decreasing the efficacy of the control.
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Affiliation(s)
- Adam Saddler
- Division of Biology, Faculty of Life Sciences, Imperial College London, Silwood Park Campus, Ascot, Berkshire, SL5 2PZ, UK. .,Faculté des Sciences, Institut de Biologie, Université de Neuchâtel, Rue Emile-Argand 11, CH-2000, Neuchâtel, Switzerland. .,Department of Health Interventions, Swiss Tropical and Public Health Institute, Socinstrasse, 57, CH-4002, Basel, Switzerland. .,Ifakara Health Institute, Box 74, Bagamoyo, Tanzania. .,University of Basel, Petersplatz 1, Basel, 4003, Switzerland.
| | | | - Jacob C Koella
- Faculté des Sciences, Institut de Biologie, Université de Neuchâtel, Rue Emile-Argand 11, CH-2000, Neuchâtel, Switzerland.
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Sternberg ED, Waite JL, Thomas MB. Evaluating the efficacy of biological and conventional insecticides with the new 'MCD bottle' bioassay. Malar J 2014; 13:499. [PMID: 25515850 PMCID: PMC4300847 DOI: 10.1186/1475-2875-13-499] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 12/12/2014] [Indexed: 11/17/2022] Open
Abstract
Background Control of mosquitoes requires the ability to evaluate new insecticides and to monitor resistance to existing insecticides. Monitoring tools should be flexible and low cost so that they can be deployed in remote, resource poor areas. Ideally, a bioassay should be able to simulate transient contact between mosquitoes and insecticides, and it should allow for excito-repellency and avoidance behaviour in mosquitoes. Presented here is a new bioassay, which has been designed to meet these criteria. This bioassay was developed as part of the Mosquito Contamination Device (MCD) project and, therefore, is referred to as the MCD bottle bioassay. Methods Presented here are two experiments that serve as a proof-of-concept for the MCD bottle bioassay. The experiments used four insecticide products, ranging from fast-acting, permethrin-treated, long-lasting insecticide nets (LLINs) that are already widely used for malaria vector control, to the slower acting entomopathogenic fungus, Beauveria bassiana, that is currently being evaluated as a prospective biological insecticide. The first experiment used the MCD bottle to test the effect of four different insecticides on Anopheles stephensi with a range of exposure times (1 minute, 3 minutes, 1 hour). The second experiment is a direct comparison of the MCD bottle and World Health Organization (WHO) cone bioassay that tests a subset of the insecticides (a piece of LLIN and a piece of netting coated with B. bassiana spores) and a further reduced exposure time (5 seconds) against both An. stephensi and Anopheles gambiae. Immediate knockdown and mortality after 24 hours were assessed using logistic regression and daily survival was assessed using Cox proportional hazards models. Results Across both experiments, fungus performed much more consistently than the chemical insecticides but measuring the effect of fungus required monitoring of mosquito mortality over several days to a week. Qualitatively, the MCD bottle and WHO cone performed comparably, although knockdown and 24 hour mortality tended to be higher in some, but not all, groups of mosquitoes exposed using the WHO cone. Conclusion The MCD bottle is feasible as a flexible, low-cost method for testing insecticidal materials. It is promising as a tool for testing transient contact and for capturing the effects of mosquito behavioural responses to insecticides.
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Affiliation(s)
- Eleanore D Sternberg
- Center for Infectious Disease Dynamics and Department of Entomology, Pennsylvania State University, University Park, PA, USA.
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Lei Z, Lv Y, Wang W, Guo Q, Zou F, Hu S, Fang F, Tian M, Liu B, Liu X, Ma K, Ma L, Zhou D, Zhang D, Sun Y, Shen B, Zhu C. MiR-278-3p regulates pyrethroid resistance in Culex pipiens pallens. Parasitol Res 2014; 114:699-706. [PMID: 25420996 DOI: 10.1007/s00436-014-4236-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 11/14/2014] [Indexed: 12/17/2022]
Abstract
MicroRNAs (miRNAs) regulate gene expression and biological processes including embryonic development, innate immunity, and infection in many species. Emerging evidence indicates that miRNAs are involved in drug resistance. However, little is known about the relationship between the miRNAs and insecticide resistance in mosquitos. Here, we reported that conserved miR-278-3p and its target gene are critical for pyrethroid resistance in Culex pipiens pallens. We found that CYP6AG11 is the target of miR-278-3p, through bioinformatic analysis and experimental verification. The expression level of miR-278-3p was lower, whereas the level of CYP6AG11 was higher in deltamethrin-resistant strain, which were detected using quantitative reverse transcription PCR (qRT-PCR). We also found that CYP6AG11 was regulated by miR-278-3p via a specific target site with the 3' untranslated region (UTR) by luciferase reporter assay. In addition, overexpression of CYP6AG11 in the mosquito C6/36 cells showed better proliferation than the cells with empty vector when treated by deltamethrin at different concentrations. Moreover, the overexpression of miR-278-3p through microinjection led to a significant reduction in the survival rate, and the level of CYP6AG11 was simultaneously reduced. These results indicated that miR-278-3p could regulate the pyrethroid resistance through CYP6AG11.
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Affiliation(s)
- Zhentao Lei
- Department of Pathogen Biology, Nanjing Medical University, Nanjing, China
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Aïzoun N, Azondekon R, Aïkpon R, Gnanguenon V, Osse R, Asidi A, Akogbéto M. Study of the efficacy of a Wheaton coated bottle with permethrin and deltamethrin in laboratory conditions and a WHO impregnated paper with bendiocarb in field conditions. Asian Pac J Trop Biomed 2014; 4:492-7. [PMID: 25182952 DOI: 10.12980/apjtb.4.2014c1111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Accepted: 05/12/2014] [Indexed: 10/25/2022] Open
Abstract
OBJECTIVE To determine the efficacy of WHO impregnated paper and CDC coated bottle based on number of storage days and number of times of consecutive use, in the assessment of insecticide vector susceptibility tests in laboratory and field conditions. METHODS Larvae and pupae of Anopheles gambiae s.l. mosquitoes were collected from the breeding sites in Seme-Kpodji and Cotonou districts in Southern Benin in April 2013 during the first rainy season. Anopheles gambiae s.l. mosquitoes were also collected from the breeding sites in Parakou district in Northern Benin in May 2013 at the beginning of the rainy season. Susceptibility tests were done using impregnated paper with bendiocarb (0.1%) following WHO protocol and stock solutions of permethrin (21.5 µg per bottle) and deltamethrin (12.5 µg per bottle) following CDC protocol on unfed female mosquitoes aged 2-5 days old. These bioassays were repeated a certain number of times. The temperature and relative humidity were monitored and recorded during the susceptibility tests. RESULTS This study showed that a WHO impregnated paper with bendiocarb could be used four times during four consecutive days in field conditions. Regarding a Wheaton coated bottle with permethrin or deltamethrin, they could be used at least three times during four consecutive days in laboratory conditions. CONCLUSIONS The day storage and the number of times that a WHO impregnated paper and a CDC coated bottle maintained their efficacy are useful in the assessment of insecticide vectors susceptibility tests.
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Affiliation(s)
- Nazaire Aïzoun
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Bénin ; Faculté des Sciences et Techniques, Université d'Abomey Calavi, Calavi, Bénin
| | - Roseric Azondekon
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Bénin ; University of Massachusetts Amherst, Amherst, Massachusetts, USA
| | - Rock Aïkpon
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Bénin ; Faculté des Sciences et Techniques, Université d'Abomey Calavi, Calavi, Bénin
| | - Virgile Gnanguenon
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Bénin ; Faculté des Sciences et Techniques, Université d'Abomey Calavi, Calavi, Bénin
| | - Razaki Osse
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Bénin ; Faculté des Sciences et Techniques, Université d'Abomey Calavi, Calavi, Bénin
| | - Alex Asidi
- London School of Hygiene and Tropical Medecine, Keppel Street WC1E 7HT, United Kingdom
| | - Martin Akogbéto
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Bénin ; Faculté des Sciences et Techniques, Université d'Abomey Calavi, Calavi, Bénin
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Aïzoun N, Aïkpon R, Akogbéto M. Evidence of increasing L1014F kdr mutation frequency in Anopheles gambiae s.l. pyrethroid resistant following a nationwide distribution of LLINs by the Beninese National Malaria Control Programme. Asian Pac J Trop Biomed 2014; 4:239-43. [PMID: 25182444 DOI: 10.1016/s2221-1691(14)60238-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 01/20/2014] [Indexed: 10/23/2022] Open
Abstract
OBJECTIVE To determine the susceptibility status to pyrethroid in Anopheles gambiae s.l. (An. gambiae), the distribution of kdr "Leu-Phe" mutation in malaria vectors in Benin and to compare the current frequency of kdr "Leu-Phe" mutation to the previous frequency after long-lasting insecticide treated nets implementation. METHODS Larvae and pupae of An. gambiae s.l. mosquitoes were collected from the breeding sites in Littoral, Zou, Borgou and Alibori provinces. CDC susceptibility tests were conducted on unfed females mosquitoes aged 2-5 d old. An. gambiae mosquitoes were identified to species using PCR techniques. Molecular assays were also carried out to identify kdr mutations in individual mosquitoes. RESULTS The results showed that An. gambiae Malanville and Suru-lere populations were resistant to deltamethrin. Regarding An. gambiae Parakou and Bohicon populations, they were resistant to permethrin. PCR revealed 100% of mosquitoes tested were An. gambiae s.s. The L1014F kdr mutation was found in An. gambiae s.s. Malanville and Parakou at various allelic frequencies. The increase of kdr allelic frequency was positively correlated with CDC bioassays data. CONCLUSIONS : Pyrethroid resistance is widespread in malaria vector in Benin and kdr mutation is the main resistance mechanism involved. More attention may be paid for the future success of malaria control programmes based on LLINs with pyrethroids in the country.
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Affiliation(s)
- Nazaire Aïzoun
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Bénin ; Faculté des Sciences et Techniques, Université d'Abomey Calavi, Calavi, Bénin
| | - Rock Aïkpon
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Bénin ; Faculté des Sciences et Techniques, Université d'Abomey Calavi, Calavi, Bénin
| | - Martin Akogbéto
- Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Bénin ; Faculté des Sciences et Techniques, Université d'Abomey Calavi, Calavi, Bénin
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Elamathi N, Barik TK, Verma V, Velamuri PS, Bhatt RM, Sharma SK, Raghavendra K. Standardization of a bottle assay--an indigenous method for laboratory and field monitoring of insecticide resistance and comparison with WHO adult susceptibility test. Parasitol Res 2014; 113:3859-66. [PMID: 25098343 DOI: 10.1007/s00436-014-4054-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 07/23/2014] [Indexed: 10/24/2022]
Abstract
The WHO adult susceptibility test is in use for insecticide resistance monitoring. Presently, materials are being imported from the Universiti Sains Malaysia, Malaysia and sometimes it is cost prohibitive. As an alternative, we present here a method of bottle bioassay using indigenous material. Different aspects related to the assay were studied and validated in the field. Bottle assay was standardized in the laboratory by using locally sourced material and laboratory-maintained insecticide-susceptible Anopheles stephensi and Aedes aegypti strains against technical grade deltamethrin and cyfluthrin insecticides dissolved in ethanol in a range of different concentrations. The frequency of use of the deltamethrin-coated bottles and shelf-life were determined. Discriminating dose for deltamethrin and cyfluthrin was 10 μg against An. stephensi and 2 μg against Ae. aegypti females. Insecticide-coated bottles stored at 25 to 35 °C can be used for three exposures within 7 days of coating. The study carried out in the laboratory was validated on wild caught An. culicifacies in the states of Odisha and Chhattisgarh against deltamethrin-coated bottles in comparison to WHO adult susceptibility test. Results of the study indicated that deltamethrin-coated bottles were effective up to three exposures within 7 days of coating for field population and 100% mortality was recorded within 35 min as observed in laboratory studies for field collected susceptible population. Also in the WHO adult susceptibility test, 100% knock-down within 35 min and 100% mortality after 24 h holding period were observed in susceptible population, while in it was 50% knock-down in 1 h and 64% mortality after 24 h holding period for resistant population (50% mortality in bottle assay in 60 min). The bottle assay can be used as an alternative to the WHO adult susceptibility test both in the laboratory and field for monitoring insecticide resistance in mosquito vectors using locally sourced material.
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Affiliation(s)
- N Elamathi
- Vector Control Division, National Institute of Malaria Research (ICMR), Dwarka Sector 8, New Delhi, 110077, India
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Bossou AD, Mangelinckx S, Yedomonhan H, Boko PM, Akogbeto MC, De Kimpe N, Avlessi F, Sohounhloue DCK. Chemical composition and insecticidal activity of plant essential oils from Benin against Anopheles gambiae (Giles). Parasit Vectors 2013; 6:337. [PMID: 24298981 PMCID: PMC3866997 DOI: 10.1186/1756-3305-6-337] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 11/21/2013] [Indexed: 11/16/2022] Open
Abstract
Background Insecticide resistance in sub-Saharan Africa and especially in Benin is a major public health issue hindering the control of the malaria vectors. Each Anopheles species has developed a resistance to one or several classes of the insecticides currently in use in the field. Therefore, it is urgent to find alternative compounds to conquer the vector. In this study, the efficacies of essential oils of nine plant species, which are traditionally used to avoid mosquito bites in Benin, were investigated. Methods Essential oils of nine plant species were extracted by hydrodistillation, and their chemical compositions were identified by GC-MS. These oils were tested on susceptible “kisumu” and resistant “ladji-Cotonou” strains of Anopheles gambiae, following WHO test procedures for insecticide resistance monitoring in malaria vector mosquitoes. Results Different chemical compositions were obtained from the essential oils of the plant species. The major constituents identified were as follows: neral and geranial for Cymbopogon citratus, Z-carveol, E-p-mentha-1(7),8-dien-2-ol and E-p-mentha-2,8-dienol for Cymbopogon giganteus, piperitone for Cymbopogon schoenanthus, citronellal and citronellol for Eucalyptus citriodora, p-cymene, caryophyllene oxide and spathulenol for Eucalyptus tereticornis, 3-tetradecanone for Cochlospermum tinctorium and Cochlospermum planchonii, methyl salicylate for Securidaca longepedunculata and ascaridole for Chenopodium ambrosioides. The diagnostic dose was 0.77% for C. citratus, 2.80% for E. tereticornis, 3.37% for E. citriodora, 4.26% for C. ambrosioides, 5.48% for C. schoenanthus and 7.36% for C. giganteus. The highest diagnostic doses were obtained with S. longepedunculata (9.84%), C. tinctorium (11.56%) and C. planchonii (15.22%), compared to permethrin 0.75%. A. gambiae cotonou, which is resistant to pyrethroids, showed significant tolerance to essential oils from C. tinctorium and S. longepedunculata as expected but was highly susceptible to all the other essential oils at the diagnostic dose. Conclusions C. citratus, E. tereticornis, E. citriodora, C. ambrosioides and C. schoenanthus are potential promising plant sources for alternative compounds to pyrethroids, for the control of the Anopheles malaria vector in Benin. The efficacy of their essential oils is possibly based on their chemical compositions in which major and/or minor compounds have reported insecticidal activities on various pests and disease vectors such as Anopheles.
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Affiliation(s)
| | - Sven Mangelinckx
- Laboratoire d'Etude et de Recherche en Chimie Appliquée, Ecole Polytechnique d'Abomey-Calavi, Université d'Abomey-Calavi, Cotonou 01 BP 2009, Bénin.
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Aïzoun N, Aïkpon R, Gnanguenon V, Oussou O, Agossa F, Padonou G, Akogbéto M. Status of organophosphate and carbamate resistance in Anopheles gambiae sensu lato from the south and north Benin, West Africa. Parasit Vectors 2013; 6:274. [PMID: 24330550 PMCID: PMC3856461 DOI: 10.1186/1756-3305-6-274] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2013] [Accepted: 09/17/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND With the rapid spread of pyrethroid resistance in the main malaria vectors from Benin and the various resistance mechanisms involved (metabolic resistance and knock-down resistance (kdr), it is important to foresee effective resistance management strategies. Thus, the knowledge of the insensitive acetylcholinesterase (ace-1R) effects on phenotypes of An. gambiae will help us to strengthen basic and operational research on the development of strategies that will use organophosphates or carbamates as alternatives against pyrethroids-resistant malaria vectors in the field. METHODS Larvae and pupae of Anopheles gambiae s.l. mosquitoes were collected from the breeding sites in Ouemé , Atacora, and Alibori departments. CDC susceptibility tests were conducted on unfed female mosquitoes aged 2-5 days old. CDC bioassays were performed with stock solutions of fenitrothion (50 μg per bottle) and bendiocarb (12.5 μg per bottle). PCR techniques were used to detect species and Ace-1 mutations. RESULTS Anopheles gambiae Seme and Kandi populations were susceptible to fenitrothion whereas Anopheles gambiae Tanguieta and Malanville populations were resistant. An. gambiae populations from Seme, Kandi and Malanville were fully susceptible to bendiocarb whereas those from Tanguieta have developed a strong resistance to the same insecticide. A slight decrease in mortality rate was observed with 97.91% in populations of mosquitoes from Malanville. PCR revealed that all specimens tested were Anopheles gambiae s.s.. CONCLUSION This study demonstrated the need to monitor organophosphate (OPs) and Carbamates resistance among populations of the An. gambiae s.l. in Benin, to determine its spread and anticipate vector control failure where these insecticides are used. However, further studies are needed to understand the current distribution of the Ace-1R mutation in other localities in the south-north transect Benin.
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Aïzoun N, Aïkpon R, Padonou GG, Oussou O, Oké-Agbo F, Gnanguenon V, Ossè R, Akogbéto M. Mixed-function oxidases and esterases associated with permethrin, deltamethrin and bendiocarb resistance in Anopheles gambiae s.l. in the south-north transect Benin, West Africa. Parasit Vectors 2013; 6:223. [PMID: 23919515 PMCID: PMC3750545 DOI: 10.1186/1756-3305-6-223] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2013] [Accepted: 08/03/2013] [Indexed: 12/02/2022] Open
Abstract
Background Insecticide resistance monitoring is essential to help national programmers to implement more effective and sustainable malaria control strategies in endemic countries. The current study aimed at an exploring the involvement of detoxifying enzymes in the insecticide phenotype resistance in Anopheles gambiae s.l.from Benin, in order to guide future malaria vector control interventions. Methods Larvae and pupae of Anopheles gambiae s.l. mosquitoes were collected from the breeding sites in Oueme, Atacora and Alibori provinces. CDC susceptibility tests were conducted on unfed female mosquitoes aged 2–5 days old. CDC bioassays were performed with stock solutions of permethrin (21.5 μg per bottle), deltamethrin (12.5 μg per bottle) and bendiocarb (12.5 μg per bottle). CDC biochemical assays using synergists were also conducted to assess the metabolic resistance. Results The susceptibility of Anopheles gambiae Agbalilame and Kandi populations to permethrin and deltamethrin respectively, increased significantly when synergized by PBO, suggesting an implication of mono-oxygenases in resistance of Anopheles gambiae s.l. to pyrethroid. Esterases may play a role in bendiocarb resistance in Anopheles gambiae Tanguieta. Conclusion Synergists partially restored susceptibility to pyrethroid and carbamate insecticides and might help mitigate the impact of vector resistance in Anopheles gambiae Agbalilame, Kandi and Tanguieta populations. However, additional vector control tools are needed to further impact on malaria transmission in such settings.This will improve the implementation and management of future control programs against this important malaria vector in Benin and in Africa in general.
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