Review and Meta-Analysis of the Evidence for Choosing Between Specific Pyrethroids for Programmatic Purposes.

Pyrethroid resistance is widespread in malaria vectors. However, differential mortality in discriminating dose assays to different pyrethroids is often observed in wild populations. When this occurs, it is unclear if this differential mortality should be interpreted as an indication of differential levels of susceptibility within the pyrethroid class, and if so, if countries should consider selecting one specific pyrethroid for programmatic use over another. A review of evidence from molecular studies, resistance testing with laboratory colonies and wild populations, and mosquito behavioural assays was conducted to answer these questions. Evidence suggests that in areas where pyrethroid resistance exists, different results in insecticide susceptibility assays with specific pyrethroids currently in common use (deltamethrin, permethrin, α-cypermethrin and λ-cyhalothrin) are not necessarily indicative of an operationally relevant difference in potential performance. Consequently, it is not advisable to use rotation between these pyrethroids as an insecticide resistance management strategy. Less commonly used pyrethroids (bifenthrin and etofenprox) may have sufficiently different modes of action, though further work would be needed to examine how this may apply to insecticide resistance management.

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Review and Meta-Analysis of the Evidence for Choosing between Specific Pyrethroids for Programmatic Purposes

Insects ◽

10.3390/insects12090826 ◽

2021 ◽

Vol 12 (9) ◽

pp. 826

Author(s):

Natalie Lissenden ◽

Mara Kont ◽

John Essandoh ◽

Hanafy Ismail ◽

Thomas Churcher ◽

...

Keyword(s):

Insecticide Resistance ◽

Pyrethroid Resistance ◽

Meta Analysis ◽

Resistance Management ◽

Malaria Vectors ◽

Resistance Testing ◽

Differential Mortality ◽

Wild Populations ◽

Insecticide Resistance Management ◽

Laboratory Colonies

Pyrethroid resistance is widespread in malaria vectors. However, differential mortality in discriminating dose assays to different pyrethroids is often observed in wild populations. When this occurs, it is unclear if this differential mortality should be interpreted as an indication of differential levels of susceptibility within the pyrethroid class, and if so, if countries should consider selecting one specific pyrethroid for programmatic use over another. A review of evidence from molecular studies, resistance testing with laboratory colonies and wild populations, and mosquito behavioural assays were conducted to answer these questions. Evidence suggested that in areas where pyrethroid resistance exists, different results in insecticide susceptibility assays with specific pyrethroids currently in common use (deltamethrin, permethrin, α-cypermethrin, and λ-cyhalothrin) are not necessarily indicative of an operationally relevant difference in potential performance. Consequently, it is not advisable to use rotation between these pyrethroids as an insecticide-resistance management strategy. Less commonly used pyrethroids (bifenthrin and etofenprox) may have sufficiently different modes of action, though further work is needed to examine how this may apply to insecticide resistance management.

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Section 4. Pyrethroid and endosulfan resistance: selection and cross resistance studies

Bulletin of entomological research supplement series ◽

10.1017/s1367426900000102 ◽

1993 ◽

Vol 1 ◽

pp. 28-35 ◽

Cited By ~ 21

Author(s):

Neil W. Forrester ◽

Matthew Cahill ◽

Lisa J. Bird ◽

Jacquelyn K. Layland

Keyword(s):

Insecticide Resistance ◽

Lower Order ◽

Management Strategy ◽

Pyrethroid Resistance ◽

Resistance Management ◽

Resistance Mechanisms ◽

Cross Resistance ◽

Male And Female ◽

Insecticide Resistance Management ◽

Resistance Selection

SummaryResistance to endosulfan and pyrethroids in Helicoverpa armigera in Australia was shown to be due to multiple rather than cross resistance. The independence of the endosulfan and pyrethroid resistance mechanisms vindicates the sequential use of these two groups in Stages I and II of the insecticide resistance management strategy, respectively. Within the cyclodienes, greatest resistance occurred to dieldrin with lower order cross resistance to endosulfan and endrin. Male and female moths expressed cyclodiene resistance equally.

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Section 1. The Australian insecticide resistance management strategy

Bulletin of entomological research supplement series ◽

10.1017/s1367426900000072 ◽

1993 ◽

Vol 1 ◽

pp. 1-4 ◽

Cited By ~ 90

Author(s):

Neil W. Forrester ◽

Matthew Cahill ◽

Lisa J. Bird ◽

Jacquelyn K. Layland

Keyword(s):

Insecticide Resistance ◽

Helicoverpa Armigera ◽

Pyrethroid Resistance ◽

Resistance Management ◽

Grain Legumes ◽

Pest Species ◽

Insecticide Resistance Management ◽

Eastern Australia ◽

Helicoverpa Armígera ◽

Chemical Groups

SummaryIn response to field pyrethroid failures against Helicoverpa armigera (Hübner) in early 1983, an insecticide resistance management (IRM) strategy was introduced for insect control in summer crops in eastern Australia. The aims of this strategy were to contain the pyrethroid resistance problem, to prevent re-selection of historical endosulfan resistance (both curative IRM) and to avoid any future problems with organophosphate/carbamate resistance (preventative IRM). An alternation strategy was adopted which was based on the rotation of unrelated chemical groups on a per generation basis, along with a strong recommendation for the use of ovicidal mixtures. These chemical countermeasures were then integrated with other non-chemical control methods (biological and cultural) into a workable integrated pest management programme. The restrictions were applied to all Helicoverpa armigera susceptible crops (including cereals, oilseeds, grain legumes, tomatoes, tobacco and cotton) and even to other co-incident pest species. From its inception, compliance with the voluntary strategy has been exceptional.

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The Current Insecticide Resistance in Main Malaria Vector Anopheles arabiensis in Yemen

Journal of Tropical Medicine ◽

10.1155/2020/5625019 ◽

2020 ◽

Vol 2020 ◽

pp. 1-5

Author(s):

Zalalham Al-Koleeby ◽

Ahmed El Aboudi ◽

Mithaq Assada ◽

Mohamed Al-Hadi ◽

Mohammed Abdalr Ahman ◽

...

Keyword(s):

Insecticide Resistance ◽

Malaria Vector ◽

Anopheles Arabiensis ◽

Resistance Management ◽

Indoor Residual Spraying ◽

Malaria Vectors ◽

Test Procedures ◽

Phenotypic Resistance ◽

Lambda Cyhalothrin ◽

Susceptibility Tests

Control of malaria vectors in Yemen relies on both indoor residual spraying using carbamate (bendiocarb) and long-lasting pyrethroids-treated nets. This paper reports the results of studies conducted to monitor the insecticide resistance of the main malaria vector, Anopheles arabiensis, to the insecticides currently used in the vector control in four different locations. Susceptibility tests were performed following the WHO test procedures. Two pyrethroids (lambda-cyhalothrin 0.05% and deltamethrin 0.05%) and one carbamate (bendiocarb 0.1%) were tested at diagnostic doses (DD). The five-fold DD of lambda-cyhalothrin and deltamethrin (0.25%) were also used to yield information on the intensity of resistance. Besides, tests with synergists were performed to assess the involvement of detoxifying enzyme in the phenotypic resistance of the populations of An. arabiensis to pyrethroids. The results of the performed susceptibility bioassay showed that the vector is susceptible to bendiocarb and resistant to lambda-cyhalothrin and deltamethrin in the four studied areas. The pyrethroids resistance is solely metabolic. This information could help policy-makers to plan insecticide resistance management. Bendiocarb is still an effective insecticide in the form of IRS. Concerning LLINS, it would be interesting to assess their effectiveness, combining a pyrethroid with PBO for the control of the pyrethroid-resistant malaria vector.

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Optimizing Strategic Insecticide Resistance Management Planning in Malaria Vectors

Insecticides Resistance ◽

10.5772/61301 ◽

2016 ◽

Cited By ~ 1

Author(s):

Emmanuel Chanda

Keyword(s):

Insecticide Resistance ◽

Resistance Management ◽

Malaria Vectors ◽

Management Planning ◽

Insecticide Resistance Management

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Implementation of the global plan for insecticide resistance management in malaria vectors: Progress, challenges, and the way forward

10.1603/ice.2016.94173 ◽

2016 ◽

Author(s):

Janet Hemingway

Keyword(s):

Insecticide Resistance ◽

Resistance Management ◽

Malaria Vectors ◽

Insecticide Resistance Management ◽

The Way

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Identifying permethrin resistance loci in malaria vectors by genetic mapping

Parasitology ◽

10.1017/s0031182013000024 ◽

2013 ◽

Vol 140 (12) ◽

pp. 1468-1477 ◽

Cited By ~ 6

Author(s):

CLAUDIA WITZIG ◽

CHARLES S. WONDJI ◽

CLARE STRODE ◽

ROUSSEAU DJOUAKA ◽

HILARY RANSON

Keyword(s):

Genetic Mapping ◽

Insecticide Resistance ◽

Pyrethroid Resistance ◽

Association Studies ◽

Management Strategies ◽

Resistance Management ◽

Malaria Vectors ◽

Genome Wide Association Studies ◽

Population Structuring ◽

Genomic Locations

SUMMARYIdentification of the major loci responsible for insecticide resistance in malaria vectors would aid the development and implementation of effective resistance management strategies, which are urgently needed to tackle the growing threat posed by resistance to the limited insecticides available for malaria control. Genome-wide association studies in the major malaria vector, Anopheles gambiae, have been hindered by the high degree of within-population structuring and very low levels of linkage disequilibrium hence we revisited the use of quantitative trait loci (QTL) mapping to study resistance phenotypes in this vector species. Earlier work, identified two major QTL associated with pyrethroid resistance in A. gambiae s.s. from East Africa using genetic crossing of laboratory-colonized resistant and susceptible strains. In this study, we report the results from genetic mapping of pyrethroid resistance in three isofemale pedigrees established from wild-caught female A. gambiae s.s. mosquitoes from Benin. We identified two QTL on chromosomes 2L and 3R in these field populations, in similar genomic locations to the QTL identified in laboratory strains. The relative merits of two alternative study designs are discussed and suggestions made for future genetic mapping studies of insecticide resistance in mosquitoes.

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Mapping insecticide resistance in mosquitoes to aid malaria control

10.1101/2020.04.01.20049593 ◽

2020 ◽

Author(s):

Catherine L. Moyes ◽

Duncan Kobia Athinya ◽

Tara Seethaler ◽

Katherine Battle ◽

Marianne Sinka ◽

...

Keyword(s):

Insecticide Resistance ◽

Malaria Control ◽

Pyrethroid Resistance ◽

Resistance Management ◽

Resistance Mechanisms ◽

World Health ◽

Malaria Vector Control ◽

Metabolic Resistance ◽

Insecticide Resistance Management ◽

Health Organization

AbstractMalaria vector control may be compromised by resistance to insecticides in vector populations. Actions to mitigate against resistance rely on surveillance using standard susceptibility tests, but there are large gaps in the monitoring data. Using a published geostatistical ensemble model, we have generated maps that bridge these gaps and consider the likelihood that resistance exceeds recommended thresholds. Our results show that this model provides more accurate next-year predictions than two simpler approaches. We have used the model to generate district-level maps for the probability that pyrethroid resistance in Anopheles gambiae s.l. exceeds the World Health Organization (WHO) thresholds for susceptibility and confirmed resistance. In addition, we have mapped the three criteria for the deployment of piperonyl butoxide-treated nets that mitigate against the effects of metabolic resistance to pyrethroids. This includes a critical review of the evidence for presence of cytochrome P450-mediated metabolic resistance mechanisms across Africa. The maps for pyrethroid resistance are available on the IR Mapper website where they can be viewed alongside the latest survey data.Significance StatementMalaria control in Africa largely relies on the use of insecticides to prevent mosquitoes from transmitting the malaria parasite to humans, however, these mosquitoes have evolved resistance to these insecticides. To manage this threat to malaria control, it is vital that we map locations where the prevalence of resistance exceeds thresholds defined by insecticide resistance management plans. A geospatial model and data from Africa are used to predict locations where thresholds of resistance linked to specific recommended actions are exceeded. This model is shown to provide more accurate next-year predictions than two simpler approaches. The model is used to generate maps that aid insecticide resistance management planning and that allow targeted deployment of interventions that counter specific mechanisms of resistance.

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