scholarly journals Mapping insecticide resistance in Anopheles gambiae (s.l.) from Côte d’Ivoire

2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Soromane Camara ◽  
Alphonsine A. Koffi ◽  
Ludovic P. Ahoua Alou ◽  
Kouakou Koffi ◽  
Jean-Paul K. Kabran ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Anopheles Gambiae ◽  
Cote D'ivoire ◽  
Côte D’Ivoire ◽  
Cote D’Ivoire ◽  
Côte D'ivoire ◽  
Anopheles Gambiae S.L

scholarly journals Fine scale spatial investigation of multiple insecticide resistance and underlying target-site and metabolic mechanisms in Anopheles gambiae in central Côte d’Ivoire

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Welbeck A. Oumbouke ◽  
Patricia Pignatelli ◽  
Antoine M. G. Barreaux ◽  
Innocent Z. Tia ◽  
Alphonsine A. Koffi ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Anopheles Gambiae ◽  
Cote D'ivoire ◽  
Côte D’Ivoire ◽  
Pyrethroid Resistance ◽  
Controlled Trial ◽  
Management Strategies ◽  
Cluster Randomised Controlled Trial ◽  
Cote D’Ivoire ◽  
Côte D'ivoire

Abstract Routine monitoring of occurrence, levels and mechanisms of insecticide resistance informs effective management strategies, and should be used to assess the effect of new tools on resistance. As part of a cluster randomised controlled trial evaluating a novel insecticide-based intervention in central Côte d’Ivoire, we assessed resistance and its underlying mechanisms in Anopheles gambiae populations from a subset of trial villages. Resistance to multiple insecticides in An. gambiae s.s. and An. coluzzii was detected across villages, with dose–response assays demonstrating extremely high resistance intensity to the pyrethroid deltamethrin (> 1,500-fold), and mortality following exposure to pyrethroid-treated bednets was low (< 30% mortality in cone bioassays). The 1014F kdr mutation was almost fixed (≥ 90%) in all villages but the 1575Y kdr-amplifying mutation was relatively rare (< 15%). The carbamate and organophosphate resistance-associated Ace-1 G119S mutation was also detected at moderate frequencies (22–43%). Transcriptome analysis identified overexpression of P450 genes known to confer pyrethroid resistance (Cyp9K1, Cyp6P3, and Cyp6M2), and also a carboxylesterase (COEAE1F) as major candidates. Cyp6P3 expression was high but variable (up to 33-fold) and correlated positively with deltamethrin resistance intensity across villages (r2 = 0.78, P = 0.02). Tools and strategies to mitigate the extreme and multiple resistance provided by these mechanisms are required in this area to avoid future control failures.

scholarly journals Anopheles bionomics, insecticide resistance mechanisms, and malaria transmission in the Korhogo area, northern Côte d’Ivoire: a pre-intervention study

Parasite ◽  
2019 ◽  
Vol 26 ◽  
pp. 40 ◽  
Author(s):  
Barnabas Zogo ◽  
Dieudonné Diloma Soma ◽  
Bertin N’Cho Tchiekoi ◽  
Anthony Somé ◽  
Ludovic P. Ahoua Alou ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Anopheles Gambiae ◽  
Malaria Transmission ◽  
Cote D'ivoire ◽  
Rainy Season ◽  
Côte D’Ivoire ◽  
Resistance Mechanisms ◽  
Effective Control ◽  
Cote D’Ivoire ◽  
Côte D'ivoire

A better understanding of malaria transmission at a local scale is essential for developing and implementing effective control strategies. In the framework of a randomized controlled trial (RCT), we aimed to provide an updated description of malaria transmission in the Korhogo area, northern Côte d’Ivoire, and to obtain baseline data for the trial. We performed human landing collections (HLCs) in 26 villages in the Korhogo area during the rainy season (September–October 2016, April–May 2017) and the dry season (November–December 2016, February–March 2017). We used PCR techniques to ascertain the species of the Anopheles gambiae complex, Plasmodium falciparum sporozoite infection, and insecticide resistance mechanisms in a subset of Anopheles vectors. Anopheles gambiae s.l. was the predominant malaria vector in the Korhogo area. Overall, more vectors were collected outdoors than indoors (p < 0.001). Of the 774 An. gambiae s.l. tested in the laboratory, 89.65% were An. gambiae s.s. and 10.35% were An. coluzzii. The frequencies of the kdr allele were very high in An. gambiae s.s. but the ace-1 allele was found at moderate frequencies. An unprotected individual living in the Korhogo area received an average of 9.04, 0.63, 0.06 and 0.12 infected bites per night in September–October, November–December, February–March, and April–May, respectively. These results demonstrate that the intensity of malaria transmission is extremely high in the Korhogo area, especially during the rainy season. Malaria control in highly endemic areas such as Korhogo needs to be strengthened with complementary tools in order to reduce the burden of the disease.

scholarly journals Evaluation of Yahe® and Panda® 2.0 long-lasting insecticidal nets against wild pyrethroid-resistant Anopheles gambiae s.l. from Côte d’Ivoire: an experimental hut trial

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Cyntia-Muriel Y. Clegban ◽  
Soromane Camara ◽  
A. Alphonsine Koffi ◽  
Ludovic P. Ahoua Alou ◽  
Jean-Paul Kabran Kouame ◽  
...  
Keyword(s):  
Vector Control ◽  
Anopheles Gambiae ◽  
Cote D'ivoire ◽  
Côte D’Ivoire ◽  
Blood Feeding ◽  
Cote D’Ivoire ◽  
Experimental Hut ◽  
Côte D'ivoire ◽  
Anopheles Gambiae S.L ◽  
Long Lasting Insecticidal Nets

Abstract Background Long-lasting insecticidal nets (LLINs) have played an important role in reducing the global malaria burden since 2000. They are a core prevention tool used widely by people at risk of malaria. The Vector Control Prequalification mechanism of the Word Health Organization (WHO-Vector Control PQ) established the testing and evaluation guidelines for LLINs before registration for public use. In the present study, two new brands of deltamethrin-impregnated nets (Yahe® LN and Panda® Net 2.0) were evaluated in an experimental hut against wild pyrethroid-resistant Anopheles gambiae s.l. in M’Bé nearby Bouaké, central Côte d’Ivoire. Methods The performance of Yahe® LN and Panda® Net 2.0 was compared with that of PermaNet 2.0, conventionally treated nets (CTN), and untreated net to assess the blood-feeding inhibition, deterrence, induced exophily, and mortality. Results Cone bioassay results showed that Panda® Net 2.0, PermaNet 2.0 and Yahe® LN (both unwashed and washed 20 times) induced > 95% knockdown or > 80% mortality of the susceptible Anopheles gambiae Kisumu strain. With the pyrethroid-resistant M’Bé strain, mortality rate for all treated nets did not exceed 70%. There was a significant reduction in entry and blood feeding (p < 0.05) and an increase in exophily and mortality rates (p < 0.05) with all treatments compared to untreated nets, except the CTNs. However, the personal protection induced by these treated nets decreased significantly after 20 washes. The performance of Panda® Net 2.0 was equal to PermaNet® 2.0 in terms of inhibiting blood feeding, but better than PermaNet® 2.0 in terms of mortality. Conclusion This study showed that Yahe® LN and Panda® Net 2.0 met the WHO Pesticide Evaluation Scheme (WHOPES) criteria to undergo phase III trial at the community level. Due to an increasing spread and development of pyrethroid resistance in malaria vectors, control of malaria transmission must evolve into an integrated vector management relying on a large variety of efficient control tools. Graphical Abstract

scholarly journals Efficacy of Interceptor® G2, a new long-lasting insecticidal net against wild pyrethroid-resistant Anopheles gambiae s.s. from Côte d’Ivoire: a semi-field trial

Parasite ◽  
2018 ◽  
Vol 25 ◽  
pp. 42 ◽  
Author(s):  
Soromane Camara ◽  
Ludovic Phamien Ahoua Alou ◽  
Alphonsine Amanan Koffi ◽  
Yao Cyntia Muriel Clegban ◽  
Jean-Paul Kabran ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Vector Control ◽  
Anopheles Gambiae ◽  
Cote D'ivoire ◽  
Côte D’Ivoire ◽  
Blood Feeding ◽  
Phase Iii ◽  
Anopheles Gambiae S.S ◽  
Cote D’Ivoire ◽  
Côte D'ivoire

Background: The widespread insecticide resistance in malaria vector populations is a serious threat to the efficacy of vector control tools. As a result, the World Health Organization (WHO) supports the development of alternative tools that combine several insecticides with the aim of improving vector control and the management of insecticide resistance. In the present study, a long-lasting insecticidal net treated with a mixture of chlorfenapyr and alphacypermethrin was evaluated against wild pyrethroid-resistant Anopheles gambiae s.s in M’bé, Côte d’Ivoire. Centers for Disease Control and Prevention (CDC) bottle tests were carried out with resistant An. gambiae s.s. of M’bé and the susceptible strain, to assess the resistance level to chlorfenapyr and alphacypermethrin. Results: CDC bottle bioassays revealed a high level of resistance of An. gambiae s.s. population from M’bé to alphacypermethrin, whereas they revealed low resistance to chlorfenapyr. In experimental huts, Interceptor® G2 that was unwashed or washed 20 times killed 87% and 82% of An. gambiae s.s., respectively, whereas Interceptor® LN that was either unwashed or washed 20 times killed only about 10% of the mosquitoes. The blood-feeding inhibition induced by Interceptor® was not significantly different compared to untreated nets, whereas Interceptor® G2 that was unwashed or washed 20 times induced 42% and 34% inhibition of blood-feeding, respectively. Conclusion: Interceptor® G2 met the WHOPES criteria to undergo a phase III study. Investigation of its efficacy at a community level and the conduct of randomized controlled trials dealing with epidemiological outputs are warranted in order to study the potential of Interceptor® G2 to better protect communities.

scholarly journals Re-Visiting Insecticide Resistance Status in Anopheles gambiae from Côte d'Ivoire: A Nation-Wide Informative Survey

PLoS ONE ◽  
2013 ◽  
Vol 8 (12) ◽  
pp. e82387 ◽  
Author(s):  
Alphonsine A. Koffi ◽  
Ludovic P. Ahoua Alou ◽  
Jean-Paul K. Kabran ◽  
Raphael N'Guessan ◽  
Cédric Pennetier
Keyword(s):  
Insecticide Resistance ◽  
Anopheles Gambiae ◽  
Cote D'ivoire ◽  
Côte D’Ivoire ◽  
Cote D’Ivoire ◽  
Côte D'ivoire
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