Additional file 1 WHO susceptibility tests and CDC bottle assays testing conditions (Temperature ... more Additional file 1 WHO susceptibility tests and CDC bottle assays testing conditions (Temperature and humidity) of the different sites surveyed.
Bulletin De La Societe De Pathologie Exotique, 2000
... Une bâche en plastique est tendue en-dessous des tôles pour faciliter la capture desmous-tiqu... more ... Une bâche en plastique est tendue en-dessous des tôles pour faciliter la capture desmous-tiques sur le plafond. ... Cette observation confirme que la deltaméthrine exerce toujours un effet excito-répulsif, même sur les mous-tiques résistants. ...
With the interruption of larva treatments done by OCP as part of onchocerciasis control in West A... more With the interruption of larva treatments done by OCP as part of onchocerciasis control in West Africa, Simulium came back in abundance in forest regions and savannah fertile valleys. In addition to the severe discomfort, nuisance by Simulium is in certain cases incompatible with land use. Since ground treatment of larval breading sites using insecticides is not always possible or efficient, it is therefore a necessity to develop other methods among which individual protection against Simulium bites. The general objective of our study was to evaluate different vegetable oil compound repellent formulas against Simulium bites. Activities were carried out in savannah zone (Niakaramandougou) and in forest zone (Soubré) in Côte d'Ivoire. The methodology consisted in catching blackflies on volunteers whose legs were rubbed with a repellent. Gobi raw oil and coconut, palm nut and gobi formulas (lotions and creams) were tested. During each session, which lasted from 07:00 am to 12:00 and from 03:00 pm to 06:00 pm, one person did not apply any repellent and was used as the control person. The results of our experimentations show that for a given zone (savannah, forest), a repellent (coconut, palm nut, gobi) and a compound (shea butter, vaseline), there is no significant difference between protection rates obtained with lotions (maximum: 21 bites/person/day) and those obtained with creams (maximum: 30 bites/person/day). In other respects, the lotion of a given repellent seems to be efficient in savannah as in the forest, in protecting against Simulium bites. It is the same situation with creams. So, repellents can be an efficient solution against Simulium nuisance. However, experimentations should continue to confirm the high repellency of tested formulas, proceed to the identification of principles and evaluate the toxicity and irritant effect of repellents to be applied on the skin.
The effects of impregnated bednets treated with deltamethrin at a dosage of 25 mg a.i./m2 were ev... more The effects of impregnated bednets treated with deltamethrin at a dosage of 25 mg a.i./m2 were evaluated at two testing stations in Côte d'Ivoire. The first one was located in Yaokoffikro, where Anopheles gambiae s.s. are resistant to pyrethroids (including deltamethrin), and the second in M'be, close to a large rice-growing area where An. gambiae s.s. are susceptible pyrethroids. In both situations, treating bednets with deltamethrin was very effective in limiting contact between man and vector. 72% fewer female An. gambiae entered the huts in the susceptible area, whereas a decrease of 43% was recorded in the resistant area, indicating that deltamethrin still has a certain repellent effect on resistant populations of An. gambiae s.s. Overall mortality induced by bednets treated with insecticide was significantly higher in the resistant area (56.4% as versus 44.3%). An explanation for this apparent paradox is that the mosquitoes being less repelled by the insecticide remain on the treated material for longer periods of time and most of them eventually die. The results of this study indicate that bednets treated with deltamethrin are an effective prophylactic measure even in areas where An. gambiae s.s. are resistant to pyrethroids and should still be considered as a practical means of personal protection against malaria even in pyrethroid resistance areas with high frequency of kdr resistance genes.
Médecine tropicale : revue du Corps de santé colonial, 1998
Trials to assess the impact of resistance of Anopheles gambiae s.s. to permethrin and deltamethri... more Trials to assess the impact of resistance of Anopheles gambiae s.s. to permethrin and deltamethrin on the efficacy of insecticide-treated bednets were carried out from October 1997 to April 1998 in six experimental huts at the Yaokoffikro testing station in Côte d'Ivoire. Six polyester bednets were used. Two bednets were treated with permethrin at a dose of 500 mg/m2 and two with deltamethrin at 25 mg/m2. The remaining two untreated bednets served as controls. The number of Anopheles gambiae s.s. entering the hut was reduced 18% with permethrin-treated bednets and 43% with deltamethrin-treated bednets. Threefold fewer female mosquitoes were found under insecticide-treated bednets than under untreated nets (controls). The number of mosquitoes passing through the treated net was threefold lower. The number of mosquitoes exiting from the treated bednets increased twofold. The blood-feeding rate dropped by 55%. Forty percent of mosquitoes entering the permethrin-treated bednets and ...
Arboviral diseases such as dengue, Zika and chikungunya transmitted by Aedes mosquitoes have been... more Arboviral diseases such as dengue, Zika and chikungunya transmitted by Aedes mosquitoes have been reported in 34 African countries. Available data indicate that in recent years there have been dengue and chikungunya outbreaks in the West Africa subregion, in countries including Côte d’Ivoire, Burkina Faso, Gabon, Senegal, and Benin. These viral diseases are causing an increased public health burden, which impedes poverty reduction and sustainable development. Aedes surveillance and control capacity, which are key to reducing the prevalence of arboviral infections, need to be strengthened in West Africa, to provide information essential for the formulation of effective vector control strategies and the prediction of arboviral disease outbreaks. In line with these objectives, the West African Aedes Surveillance Network (WAASuN) was created in 2017 at a meeting held in Sierra Leone comprising African scientists working on Aedes mosquitoes. This manuscript describes the proceedings and ...
Entomological surveillance provides critical information on vectors for timely and appropriate ma... more Entomological surveillance provides critical information on vectors for timely and appropriate malaria vector control and strategy decision making. Owing to the widely documented insecticide resistance of malaria vectors in Côte d’Ivoire, it is necessary that any vector control intervention deployment be driven by entomological data to optimize the effectiveness and allow appropriate allocation of resources. To achieve this goal, bioassays to evaluate insecticide susceptibility, resistance intensity, and piperonyl butoxide (PBO) synergism were conducted using World Health Organization (WHO) susceptibility test kits and Centers for Disease Control and Prevention (CDC) bottles against wild collected An. gambiae s.l. from 17 sites in 2019. In addition, monthly vector bionomics were conducted in four of the sites (Sakassou, Béoumi, Dabakala and Nassian) selected based on their reported high malaria incidence. Adult mosquito collections were conducted using human landing catches (HLCs), ...
Considering the pollution and the resistance generated by chemical insecticides in Anopheles gamb... more Considering the pollution and the resistance generated by chemical insecticides in Anopheles gambiae S.L., alternative control approaches have led in this study. Larvicidal activities of the leaves of Lantana camara, Bougainvillea spectabilis and Tephrosia villosa against the fourth instar larvae of Anopheles gambiae S.L. were evaluated. The susceptibility level and the homogeneity of wild strains were determined according to the method of Sinègre. The highest mortality rates were obtained from 15mg/ml with Lantana camara and Bougainvillea spectabilis. The larvicidal activity of Lantana camara on the wild strains was higher than Bougainvillea spectabilis. These wild strains have the same sensitivity as well as the KISUMU strain towards Bougainvillea spectabilis and Lantana camara. However, the wild population response to aqueous extracts was homogeneous against Bougainvillea spectabilis and heterogeneous against Lantana camara. Lantana camara and Bougainvillea spectabilis leaves were the most active aqueous extract on larvae of Anopheles gambiae S.L.
International audienceUlcer is a disease caused by a mycobacterium present in the environment: My... more International audienceUlcer is a disease caused by a mycobacterium present in the environment: Mycobacterium ulcerans.This communicable disease occurs essentially in wet tropical regions, and in particular in west Africa where it is endemic. It is the third most common mycobacterial disease affecting humans after leprosy and tuberculosis, although it is more prevalent than either leprosy or tuberculosis in some rural areas of several countries (Benin, Côte d’Ivoire and Ghana). This has led WHO to act, and in 1998 to declare Buruli ulcer an « emerging disease » and to recognize it as a neglected tropical disease. Its development is a source of concern in Côte d’Ivoire, the country most affected in the world, with an aggregate number of 30 000 cases and more than 2000 cases detected each year. It particularly affects children living in isolated rural areas around bodies of stagnant or slowly flowing water. In order to control the disease, it is essential fully to understand its ...
From 2008 to 2017, the city of Abidjan, Côte d’Ivoire experienced several Aedes-borne disease epi... more From 2008 to 2017, the city of Abidjan, Côte d’Ivoire experienced several Aedes-borne disease epidemics which required control of the vector mosquito population based on the reduction of larval habitats and insecticidal sprays for adult mosquitoes. This study was undertaken to assess the insecticide susceptibility status of Aedes aegypti (Linnaeus) in the city of Abidjan. Immature Ae. aegypti were sampled from several larval habitats within seven communes of Abidjan and reared to adults. Three to five days old F1 emerged adults were tested for susceptibility using insecticide-impregnated papers and the synergist piperonyl butoxide (PBO) following WHO bioassay guidelines. The results showed that Ae. aegypti populations from Abidjan were resistant to 0.1% propoxur, and 1% fenitrothion, with mortality rates ranging from 0% to 54.2%. Reduced susceptibility (93.4–97.5% mortality) was observed to 0.05% deltamethrin, 0.75% permethrin, 0.05% lambda-cyhalothrin, 5% malathion, and 0.8% chlorp...
Additional file 1 WHO susceptibility tests and CDC bottle assays testing conditions (Temperature ... more Additional file 1 WHO susceptibility tests and CDC bottle assays testing conditions (Temperature and humidity) of the different sites surveyed.
Bulletin De La Societe De Pathologie Exotique, 2000
... Une bâche en plastique est tendue en-dessous des tôles pour faciliter la capture desmous-tiqu... more ... Une bâche en plastique est tendue en-dessous des tôles pour faciliter la capture desmous-tiques sur le plafond. ... Cette observation confirme que la deltaméthrine exerce toujours un effet excito-répulsif, même sur les mous-tiques résistants. ...
With the interruption of larva treatments done by OCP as part of onchocerciasis control in West A... more With the interruption of larva treatments done by OCP as part of onchocerciasis control in West Africa, Simulium came back in abundance in forest regions and savannah fertile valleys. In addition to the severe discomfort, nuisance by Simulium is in certain cases incompatible with land use. Since ground treatment of larval breading sites using insecticides is not always possible or efficient, it is therefore a necessity to develop other methods among which individual protection against Simulium bites. The general objective of our study was to evaluate different vegetable oil compound repellent formulas against Simulium bites. Activities were carried out in savannah zone (Niakaramandougou) and in forest zone (Soubré) in Côte d'Ivoire. The methodology consisted in catching blackflies on volunteers whose legs were rubbed with a repellent. Gobi raw oil and coconut, palm nut and gobi formulas (lotions and creams) were tested. During each session, which lasted from 07:00 am to 12:00 and from 03:00 pm to 06:00 pm, one person did not apply any repellent and was used as the control person. The results of our experimentations show that for a given zone (savannah, forest), a repellent (coconut, palm nut, gobi) and a compound (shea butter, vaseline), there is no significant difference between protection rates obtained with lotions (maximum: 21 bites/person/day) and those obtained with creams (maximum: 30 bites/person/day). In other respects, the lotion of a given repellent seems to be efficient in savannah as in the forest, in protecting against Simulium bites. It is the same situation with creams. So, repellents can be an efficient solution against Simulium nuisance. However, experimentations should continue to confirm the high repellency of tested formulas, proceed to the identification of principles and evaluate the toxicity and irritant effect of repellents to be applied on the skin.
The effects of impregnated bednets treated with deltamethrin at a dosage of 25 mg a.i./m2 were ev... more The effects of impregnated bednets treated with deltamethrin at a dosage of 25 mg a.i./m2 were evaluated at two testing stations in Côte d'Ivoire. The first one was located in Yaokoffikro, where Anopheles gambiae s.s. are resistant to pyrethroids (including deltamethrin), and the second in M'be, close to a large rice-growing area where An. gambiae s.s. are susceptible pyrethroids. In both situations, treating bednets with deltamethrin was very effective in limiting contact between man and vector. 72% fewer female An. gambiae entered the huts in the susceptible area, whereas a decrease of 43% was recorded in the resistant area, indicating that deltamethrin still has a certain repellent effect on resistant populations of An. gambiae s.s. Overall mortality induced by bednets treated with insecticide was significantly higher in the resistant area (56.4% as versus 44.3%). An explanation for this apparent paradox is that the mosquitoes being less repelled by the insecticide remain on the treated material for longer periods of time and most of them eventually die. The results of this study indicate that bednets treated with deltamethrin are an effective prophylactic measure even in areas where An. gambiae s.s. are resistant to pyrethroids and should still be considered as a practical means of personal protection against malaria even in pyrethroid resistance areas with high frequency of kdr resistance genes.
Médecine tropicale : revue du Corps de santé colonial, 1998
Trials to assess the impact of resistance of Anopheles gambiae s.s. to permethrin and deltamethri... more Trials to assess the impact of resistance of Anopheles gambiae s.s. to permethrin and deltamethrin on the efficacy of insecticide-treated bednets were carried out from October 1997 to April 1998 in six experimental huts at the Yaokoffikro testing station in Côte d'Ivoire. Six polyester bednets were used. Two bednets were treated with permethrin at a dose of 500 mg/m2 and two with deltamethrin at 25 mg/m2. The remaining two untreated bednets served as controls. The number of Anopheles gambiae s.s. entering the hut was reduced 18% with permethrin-treated bednets and 43% with deltamethrin-treated bednets. Threefold fewer female mosquitoes were found under insecticide-treated bednets than under untreated nets (controls). The number of mosquitoes passing through the treated net was threefold lower. The number of mosquitoes exiting from the treated bednets increased twofold. The blood-feeding rate dropped by 55%. Forty percent of mosquitoes entering the permethrin-treated bednets and ...
Arboviral diseases such as dengue, Zika and chikungunya transmitted by Aedes mosquitoes have been... more Arboviral diseases such as dengue, Zika and chikungunya transmitted by Aedes mosquitoes have been reported in 34 African countries. Available data indicate that in recent years there have been dengue and chikungunya outbreaks in the West Africa subregion, in countries including Côte d’Ivoire, Burkina Faso, Gabon, Senegal, and Benin. These viral diseases are causing an increased public health burden, which impedes poverty reduction and sustainable development. Aedes surveillance and control capacity, which are key to reducing the prevalence of arboviral infections, need to be strengthened in West Africa, to provide information essential for the formulation of effective vector control strategies and the prediction of arboviral disease outbreaks. In line with these objectives, the West African Aedes Surveillance Network (WAASuN) was created in 2017 at a meeting held in Sierra Leone comprising African scientists working on Aedes mosquitoes. This manuscript describes the proceedings and ...
Entomological surveillance provides critical information on vectors for timely and appropriate ma... more Entomological surveillance provides critical information on vectors for timely and appropriate malaria vector control and strategy decision making. Owing to the widely documented insecticide resistance of malaria vectors in Côte d’Ivoire, it is necessary that any vector control intervention deployment be driven by entomological data to optimize the effectiveness and allow appropriate allocation of resources. To achieve this goal, bioassays to evaluate insecticide susceptibility, resistance intensity, and piperonyl butoxide (PBO) synergism were conducted using World Health Organization (WHO) susceptibility test kits and Centers for Disease Control and Prevention (CDC) bottles against wild collected An. gambiae s.l. from 17 sites in 2019. In addition, monthly vector bionomics were conducted in four of the sites (Sakassou, Béoumi, Dabakala and Nassian) selected based on their reported high malaria incidence. Adult mosquito collections were conducted using human landing catches (HLCs), ...
Considering the pollution and the resistance generated by chemical insecticides in Anopheles gamb... more Considering the pollution and the resistance generated by chemical insecticides in Anopheles gambiae S.L., alternative control approaches have led in this study. Larvicidal activities of the leaves of Lantana camara, Bougainvillea spectabilis and Tephrosia villosa against the fourth instar larvae of Anopheles gambiae S.L. were evaluated. The susceptibility level and the homogeneity of wild strains were determined according to the method of Sinègre. The highest mortality rates were obtained from 15mg/ml with Lantana camara and Bougainvillea spectabilis. The larvicidal activity of Lantana camara on the wild strains was higher than Bougainvillea spectabilis. These wild strains have the same sensitivity as well as the KISUMU strain towards Bougainvillea spectabilis and Lantana camara. However, the wild population response to aqueous extracts was homogeneous against Bougainvillea spectabilis and heterogeneous against Lantana camara. Lantana camara and Bougainvillea spectabilis leaves were the most active aqueous extract on larvae of Anopheles gambiae S.L.
International audienceUlcer is a disease caused by a mycobacterium present in the environment: My... more International audienceUlcer is a disease caused by a mycobacterium present in the environment: Mycobacterium ulcerans.This communicable disease occurs essentially in wet tropical regions, and in particular in west Africa where it is endemic. It is the third most common mycobacterial disease affecting humans after leprosy and tuberculosis, although it is more prevalent than either leprosy or tuberculosis in some rural areas of several countries (Benin, Côte d’Ivoire and Ghana). This has led WHO to act, and in 1998 to declare Buruli ulcer an « emerging disease » and to recognize it as a neglected tropical disease. Its development is a source of concern in Côte d’Ivoire, the country most affected in the world, with an aggregate number of 30 000 cases and more than 2000 cases detected each year. It particularly affects children living in isolated rural areas around bodies of stagnant or slowly flowing water. In order to control the disease, it is essential fully to understand its ...
From 2008 to 2017, the city of Abidjan, Côte d’Ivoire experienced several Aedes-borne disease epi... more From 2008 to 2017, the city of Abidjan, Côte d’Ivoire experienced several Aedes-borne disease epidemics which required control of the vector mosquito population based on the reduction of larval habitats and insecticidal sprays for adult mosquitoes. This study was undertaken to assess the insecticide susceptibility status of Aedes aegypti (Linnaeus) in the city of Abidjan. Immature Ae. aegypti were sampled from several larval habitats within seven communes of Abidjan and reared to adults. Three to five days old F1 emerged adults were tested for susceptibility using insecticide-impregnated papers and the synergist piperonyl butoxide (PBO) following WHO bioassay guidelines. The results showed that Ae. aegypti populations from Abidjan were resistant to 0.1% propoxur, and 1% fenitrothion, with mortality rates ranging from 0% to 54.2%. Reduced susceptibility (93.4–97.5% mortality) was observed to 0.05% deltamethrin, 0.75% permethrin, 0.05% lambda-cyhalothrin, 5% malathion, and 0.8% chlorp...
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