Spatiotemporal multiple insecticide resistance in Aedes aegypti populations in French Guiana: need for alternative vector control

Abstract Aedes aegypti (Linnaeus, 1762) is considered the most important mosquito vector species for several arboviruses (e.g., dengue, chikungunya, Zika) in Costa Rica. The primary strategy for the control and prevention of Aedes-borne diseases relies on insecticide-based vector control. However, the emergence of insecticide resistance in the mosquito populations presents a significant threat to these prevention actions. The characterization of the mechanisms driving the insecticide resistance in Ae. aegypti is vital for decision making in vector control programs. Therefore, we analyzed the voltage-gated sodium channel (VGSC) gene for the presence of the V1016I and F1534C kdr mutations in Ae. aegypti populations from Puntarenas and Limon provinces, Costa Rica. The CDC bottle bioassays showed that both Costa Rican Ae. aegypti populations were resistant to permethrin and deltamethrin. In the case of kdr genotyping, results revealed the co-occurrence of V1016I and F1534C mutations in permethrin and deltamethrin-resistant populations, as well as the fixation of the 1534C allele. A strong association between these mutations and permethrin and deltamethrin resistance was found in Puntarenas. Limon did not show this association; however, our results indicate that the Limon population analyzed is not under the same selective pressure as Puntarenas for the VGSC gene. Therefore, our findings make an urgent call to expand the knowledge about the insecticide resistance status and mechanisms in the Costa Rican populations of Ae. aegypti, which must be a priority to develop an effective resistance management plan.

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Co-occurrence of kdr mutations V1016I and F1534C in pyrethroid-resistant Aedes aegypti (Diptera: Culicidae) populations from Costa Rica

10.1101/704767 ◽

2019 ◽

Author(s):

Aryana Zardkoohi ◽

David Castañeda ◽

Carmen Castillo ◽

Juan C Lol ◽

Francisco Lopez ◽

...

Keyword(s):

Costa Rica ◽

Aedes Aegypti ◽

Insecticide Resistance ◽

Vector Control ◽

Resistance Management ◽

Management Plan ◽

Costa Rican ◽

Mosquito Vector ◽

Control Programs ◽

Control And Prevention

AbstractAedes aegypti (Linnaeus, 1762) is considered the most important mosquito vector species for several arboviruses (e.g., dengue, chikungunya, Zika) in Costa Rica. The main strategy for the control and prevention of Aedes-borne diseases relies on insecticide-based vector control. However, the emergence of insecticide resistance in the mosquito populations present a big threat for the prevention actions. The characterization of the mechanisms driving the insecticide resistance in Ae. aegypti are vital for decision making in vector control programs. Therefore, we analyzed the voltage-gated sodium channel gene for the presence of the V1016I and F1534C kdr mutations in pyrethroid-resistant Ae. aegypti populations from Puntarenas and Limon provinces, Costa Rica. The CDC bottle bioassays showed that both Costa Rican Ae. aegypti populations were resistant to permethrin and deltamethrin. In the case of kdr genotyping, results revealed the co-occurrence of V1016I and F1534C mutations in permethrin and deltamethrin-resistant populations, as well as the fixation of the 1534C allele. Therefore, our findings make an urgent call to expand the knowledge about the insecticide resistance status and mechanisms in the Costa Rican populations of Ae. aegypti which must be a priority to develop an effective resistance management plan.

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Evaluation of the resistance to insecticides in Aedes aegypti, transmitter of dengue, in Latin America

Mexican Journal of Medical Research ◽

10.29057/mjmr.v8i15.3912 ◽

2020 ◽

Vol 8 (15) ◽

pp. 23-28

Author(s):

Amparo Gabriela Hernández Ramos

Keyword(s):

Infectious Disease ◽

Latin America ◽

Aedes Aegypti ◽

Insecticide Resistance ◽

Vector Control ◽

Latin American ◽

Female Mosquito ◽

The World ◽

Different Seasons ◽

Latin American Countries

Dengue is an infectious disease with high rates of morbidity and mortality, transmitted by the bite of the female mosquito of the genus Aedes aegypti, vector distributed in tropical and subtropical areas throughout the world. America is one of the most affected regions. This vector is controlled through insecticides that due to its constant use in populations, a resistance phenomenon has been produced. The objective of this review is to identify the situation of insecticide resistance in populations of Aedes aegypti in Latin American countries. In this region, several insecticides have been used for vector control; in the last 10 years insecticides of the pyrethroid and organophosphorus group have been used as adulticides for the control of the mosquito, conditioning resistance. Some insecticides such as organophosphates and deltamethrin, despite of not being intensively used in Latin American countries, also show resistance. Improvements in vector control are required, including the rotation of the insecticides during the different seasons, as well as innovating techniques and forms of vector control

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Insecticide resistance in dengue vectors from hotspots in Selangor, Malaysia

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009205 ◽

2021 ◽

Vol 15 (3) ◽

pp. e0009205

Author(s):

Rosilawati Rasli ◽

Yoon Ling Cheong ◽

M. Khairuddin Che Ibrahim ◽

Siti Futri Farahininajua Fikri ◽

Rusydi Najmuddin Norzali ◽

...

Keyword(s):

Aedes Aegypti ◽

Insecticide Resistance ◽

Vector Control ◽

Aedes Albopictus ◽

World Health ◽

Dengue Vector ◽

Organophosphate Insecticide ◽

Potential Threat ◽

Pyrethroid Insecticides ◽

Dengue Vector Control

Background In Malaysia, dengue remains a top priority disease and usage of insecticides is the main method for dengue vector control. Limited baseline insecticide resistance data in dengue hotspots has prompted us to conduct this study. The present study reports the use of a map on the insecticide susceptibility status of Aedes aegypti and Aedes albopictus to provide a quick visualization and overview of the distribution of insecticide resistance. Method and results The insecticide resistance status of Aedes populations collected from 24 dengue hotspot areas from the period of December 2018 until June 2019 was proactively monitored using the World Health Organization standard protocol for adult and larval susceptibility testing was conducted, together with elucidation of the mechanisms involved in observed resistance. For resistance monitoring, susceptibility to three adulticides (permethrin, deltamethrin, and malathion) was tested, as well as susceptibility to the larvicide, temephos. Data showed significant resistance to both deltamethrin and permethrin (pyrethroid insecticides), and to malathion (organophosphate insecticide) in all sampled Aedes aegypti populations, while variable resistance patterns were found in the sampled Aedes albopictus populations. Temephos resistance was observed when larvae were tested using the diagnostic dosage of 0.012mg/L but not at the operational dosage of 1mg/L for both species. Conclusion The present study highlights evidence of a potential threat to the effectiveness of insecticides currently used in dengue vector control, and the urgent requirement for insecticide resistance management to be integrated into the National Dengue Control Program.

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Spatial variation of insecticide resistance in the dengue vector Aedes aegypti presents unique vector control challenges

Parasites & Vectors ◽

10.1186/s13071-016-1346-3 ◽

2016 ◽

Vol 9 (1) ◽

Cited By ~ 61

Author(s):

Regan Deming ◽

Pablo Manrique-Saide ◽

Anuar Medina Barreiro ◽

Edgar Ulises Koyoc Cardeña ◽

Azael Che-Mendoza ◽

...

Keyword(s):

Aedes Aegypti ◽

Insecticide Resistance ◽

Spatial Variation ◽

Vector Control ◽

Dengue Vector ◽

Unique Vector

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Spatial variation in the frequency of knockdown resistance genotypes in Florida Aedes aegypti populations

10.21203/rs.2.20163/v4 ◽

2020 ◽

Author(s):

Stephanie Jane Mundis ◽

Alden S. Estep ◽

Christy M. Waits ◽

Sadie J. Ryan

Keyword(s):

Aedes Aegypti ◽

Insecticide Resistance ◽

Vector Control ◽

Mosquito Species ◽

Explanatory Power ◽

Beta Regression ◽

Knockdown Resistance ◽

Resistant Variant ◽

Pyrethroid Insecticides ◽

Use Factors

Abstract Background The development of insecticide resistance in disease-vectoring mosquito species can lead to vector control failure and disease resurgence. However, insecticide applications remain an essential public health intervention. In Florida, insecticide resistance in Aedes aegypti , an anthropophilic mosquito species capable of transmitting dengue, chikungunya, and Zika virus, is a major concern. Understanding the location, scale, and driving factors of insecticide resistance can enhance the ability of vector control organizations to target populations effectively. Methods We used previously collected data on frequencies of mutations that confer resistance to commonly used pyrethroid insecticides in Aedes aegypti specimens from 62 sites distributed across 18 counties in Florida. To determine the scale of clustering for the most resistant variant, we used a Ripley’s K function. We also used a spatial scanning statistic technique to identify the locations of clusters where higher than expected frequencies of susceptible or resistant mosquitoes occurred. We then tested for associations between landscape, demographic, and insecticide-use factors using a beta regression modelling approach and evaluated the effect of spatial lag and spatial error terms on overall explanatory power of these models. Results The scale at which maximum clustering of the most resistant variant occurs is approximately 20 kilometers. We identified statistically significant clusters of genotypes associated with resistancein several coastal cities, although some of these clusters were near significant clusters of susceptible mosquitoes, indicating selection pressures vary at the local scale. Vegetation density, distance from roads, and pyrethroid-use by vector control districts were consistently significant predictors of knockdown resistance genotype frequency in the top-performing beta regression models, although pyrethroid-use surprisingly had a negatively associated with resistance. The incorporation of spatial lags resulted in improvements to the fit and explanatory power of the models, indicating an underlying diffusion process likely explains some of the spatial patterns observed. Conclusions The genetic mutations that confer resistance to pyrethroids in Aedes aegpyti mosquitoes in Florida exhibit spatial autocorrelation and patterns that can be partially explained by landscape and insecticide-use factors. Further work at local scales should be able to identify the mechanisms by which these variables influence selection for alleles associated with resistance.

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Insecticide resistance and genetic structure of Aedes aegypti populations from Rio de Janeiro State, Brazil

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0008492 ◽

2021 ◽

Vol 15 (2) ◽

pp. e0008492 ◽

Cited By ~ 1

Author(s):

Rafi Ur Rahman ◽

Luciano Veiga Cosme ◽

Monique Melo Costa ◽

Luana Carrara ◽

José Bento Pereira Lima ◽

...

Keyword(s):

Gene Flow ◽

Genetic Structure ◽

Aedes Aegypti ◽

Insecticide Resistance ◽

Vector Control ◽

Rio De Janeiro ◽

Control Program ◽

Positive Control ◽

World Health ◽

Janeiro State

Vector control largely relies on neurotoxic chemicals, and insecticide resistance (IR) directly threatens their effectiveness. In some cases, specific alleles cause IR, and knowledge of the genetic diversity and gene flow among mosquito populations is crucial to track their arrival, rise, and spread. Here we evaluated Aedes aegypti populations’ susceptibility status, collected in 2016 from six different municipalities of Rio de Janeiro state (RJ), to temephos, pyriproxyfen, malathion, and deltamethrin. We collected eggs of Ae. aegypti in Campos dos Goytacazes (Cgy), Itaperuna (Ipn), Iguaba Grande (Igg), Itaboraí (Ibr), Mangaratiba (Mgr), and Vassouras (Vsr). We followed the World Health Organization (WHO) guidelines and investigated the degree of susceptibility/resistance of mosquitoes to these insecticides. We used the Rockefeller strain as a susceptible positive control. We genotyped the V1016I and F1534C knockdown resistance (kdr) alleles using qPCR TaqMan SNP genotyping assay. Besides, with the use of Ae. aegypti SNP-chip, we performed genomic population analyses by genotyping more than 15,000 biallelic SNPs in mosquitoes from each population. We added previous data from populations from other countries to evaluate the ancestry of RJ populations. All RJ Ae. aegypti populations were susceptible to pyriproxyfen and malathion and highly resistant to deltamethrin. The resistance ratios for temephos was below 3,0 in Cgy, Ibr, and Igg populations, representing the lowest rates since IR monitoring started in this Brazilian region. We found the kdr alleles in high frequencies in all populations, partially justifying the observed resistance to pyrethroid. Population genetics analysis showed that Ae. aegypti revealed potential higher migration among some RJ localities and low genetic structure for most of them. Future population genetic studies, together with IR data in Ae aegypti on a broader scale, can help us predict the gene flow within and among the Brazilian States, allowing us to track the dynamics of arrival and changes in the frequency of IR alleles, and providing critical information to improving vector control program.

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Spatial variation in the frequency of knockdown resistance genotypes in Florida Aedes aegypti populations

10.21203/rs.2.19136/v1 ◽

2019 ◽

Author(s):

Stephanie Jane Mundis ◽

Alden S. Estep ◽

Christy M. Waits ◽

Sadie J. Ryan

Keyword(s):

Aedes Aegypti ◽

Insecticide Resistance ◽

Vector Control ◽

Mosquito Species ◽

Explanatory Power ◽

Beta Regression ◽

Spatial Error ◽

Resistant Variant ◽

Pyrethroid Insecticides ◽

Use Factors

Abstract BackgroundThe development of insecticide resistance in disease-vectoring mosquito species can lead to vector control failure and disease resurgence. However, insecticide applications remain an essential public health intervention. In Florida, insecticide resistance in Aedes aegypti, an anthropophilic mosquito species capable of transmitting dengue, chikungunya, and Zika virus, is a major concern. Understanding the location, scale, and driving factors of insecticide resistance can enhance the ability of vector control organizations to target populations effectively.MethodsWe used previously collected data on frequencies of mutations that confer resistance to commonly used pyrethroid insecticides in Aedes aegypti specimens from 62 sites distributed across 18 counties in Florida. To determine the scale of clustering for the most resistant variant, we used a Ripley’s K function. We also used a spatial scanning statistic technique to identify the locations of clusters where higher than expected frequencies of susceptible or resistant mosquitoes occurred. We then tested for associations between landscape, demographic, and insecticide-use factors using a beta regression modelling approach and evaluated the effect of spatial lag and spatial error terms on overall explanatory power of these models. ResultsThe scale at which maximum clustering of the most resistant variant occurs is approximately 20 kilometers. We identified statistically significant clusters of resistance in several coastal cities, although some of these clusters were near significant clusters of susceptible mosquitoes, indicating selection pressures vary at the local scale. Vegetation density, distance from roads, and pyrethroid-use by vector control districts were consistently significant predictors of insecticide resistance frequency in the top-performing beta regression models, although pyrethroid-use surprisingly had a negatively associated with resistance. The incorporation of spatial lags resulted in improvements to the fit and explanatory power of the models, indicating an underlying diffusion process likely explains some of the spatial patterns in resistance observed.ConclusionsThe genetic mutations that confer resistance to pyrethroids in Aedes aegpyti mosquitoes in Florida exhibit spatial autocorrelation and patterns that can be partially explained by landscape and insecticide-use factors. Further work at local scales should be able to identify the mechanisms by which these variables influence the outcome of resistance.

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Spatial variation in the frequency of knockdown resistance genotypes in Florida Aedes aegypti populations

10.21203/rs.2.20163/v2 ◽

2020 ◽

Author(s):

Stephanie Jane Mundis ◽

Alden S. Estep ◽

Christy M. Waits ◽

Sadie J. Ryan

Keyword(s):

Aedes Aegypti ◽

Insecticide Resistance ◽

Vector Control ◽

Mosquito Species ◽

Explanatory Power ◽

Beta Regression ◽

Knockdown Resistance ◽

Resistant Variant ◽

Pyrethroid Insecticides ◽

Use Factors

Abstract Background The development of insecticide resistance in disease-vectoring mosquito species can lead to vector control failure and disease resurgence. However, insecticide applications remain an essential public health intervention. In Florida, insecticide resistance in Aedes aegypti , an anthropophilic mosquito species capable of transmitting dengue, chikungunya, and Zika virus, is a major concern. Understanding the location, scale, and driving factors of insecticide resistance can enhance the ability of vector control organizations to target populations effectively. Methods We used previously collected data on frequencies of mutations that confer resistance to commonly used pyrethroid insecticides in Aedes aegypti specimens from 62 sites distributed across 18 counties in Florida. To determine the scale of clustering for the most resistant variant, we used a Ripley’s K function. We also used a spatial scanning statistic technique to identify the locations of clusters where higher than expected frequencies of susceptible or resistant mosquitoes occurred. We then tested for associations between landscape, demographic, and insecticide-use factors using a beta regression modelling approach and evaluated the effect of spatial lag and spatial error terms on overall explanatory power of these models. Results The scale at which maximum clustering of the most resistant variant occurs is approximately 20 kilometers. We identified statistically significant clusters of genotypes associated with resistancein several coastal cities, although some of these clusters were near significant clusters of susceptible mosquitoes, indicating selection pressures vary at the local scale. Vegetation density, distance from roads, and pyrethroid-use by vector control districts were consistently significant predictors of knockdown resistance genotype frequency in the top-performing beta regression models, although pyrethroid-use surprisingly had a negatively associated with resistance. The incorporation of spatial lags resulted in improvements to the fit and explanatory power of the models, indicating an underlying diffusion process likely explains some of the spatial patterns observed. Conclusions The genetic mutations that confer resistance to pyrethroids in Aedes aegpyti mosquitoes in Florida exhibit spatial autocorrelation and patterns that can be partially explained by landscape and insecticide-use factors. Further work at local scales should be able to identify the mechanisms by which these variables influence selection for alleles associated with resistance.

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