Review of Temephos Discriminating Concentration for Monitoring the Susceptibility of Anopheles labranchiae (Falleroni, 1926), Malaria Vector in Morocco

In Morocco, the resistance monitoring of Anopheles labranchiae larvae to temephos is done using discriminating concentration of 0.125 mg, which is half of the WHO recommended dose for Anopheles. However, this dosage seemed to be too high to allow an early detection of the resistance and its revision was found necessary. The present study was carried out during May-June 2008 and 2009 in nine provinces from the north-west of the country. The aim was to determine the lethal concentrations LC100 of temephos for the most susceptible populations and to define the discriminating dosage as the double of this value. The bioassays were conducted according to WHO standard operating protocol to establish the dose-mortality relationship and deduct the LC50 and LC95. The results of this study indicated that the LC100 obtained on the most susceptible populations was close to 0.05 mg/L. Therefore, the temephos discriminating dosage for susceptibility monitoring of An. labranchiae larvae in Morocco was set to be 0.1 mg/L

Insecticide susceptibility status of Phlebotomus (Paraphlebotomus) sergenti and Phlebotomus (Phlebotomus) papatasi in endemic foci of cutaneous leishmaniasis in Morocco

<p>Abstract</p> <p>Background</p> <p>In Morocco, cutaneous leishmaniasis is transmitted by <it>Phlebotomus sergenti </it>and <it>Ph. papatasi</it>. Vector control is mainly based on environmental management but indoor residual spraying with synthetic pyrethroids is applied in many foci of <it>Leishmania tropica</it>. However, the levels and distribution of sandfly susceptibility to insecticides currently used has not been studied yet. Hence, this study was undertaken to establish the susceptibility status of <it>Ph. sergenti </it>and <it>Ph. papatasi </it>to lambdacyhalothrin, DDT and malathion.</p> <p>Methods</p> <p>The insecticide susceptibility status of <it>Ph. sergenti </it>and <it>Ph. papatasi </it>was assessed during 2011, following the standard WHO technique based on discriminating dosage. A series of twenty-five susceptibility tests were carried out on wild populations of <it>Ph. sergenti </it>and <it>Ph. papatasi </it>collected by CDC light traps from seven villages in six different provinces. Knockdown rates (KDT) were noted at 5 min intervals during the exposure to DDT and to lambdacyhalothrin. After one hour of exposure, sandflies were transferred to the observation tubes for 24 hours. After this period, mortality rate was calculated. Data were analyzed by Probit analysis program to determine the knockdown time 50% and 90% (KDT50 and KDT90) values.</p> <p>Results</p> <p>Study results showed that <it>Ph.sergenti </it>and <it>Ph. papatasi </it>were susceptible to all insecticides tested. Comparison of KDT values showed a clear difference between the insecticide knockdown effect in studied villages. This effect was lower in areas subject to high selective public health insecticide pressure in the framework of malaria or leishmaniasis control.</p> <p>Conclusion</p> <p><it>Phlebotomus sergenti </it>and <it>Ph. papatasi </it>are susceptible to the insecticides tested in the seven studied villages but they showed a low knockdown effect in Azilal, Chichaoua and Settat. Therefore, a study of insecticide susceptibility of these vectors in other foci of leishmaniasis is recommended and the level of their susceptibility should be regularly monitored.</p

Entomological investigations in the region of the last malaria focus in Morocco

To evaluate the risk of malaria transmission resumption in Morocco, we have studied the current level of receptivity of the region of the last malaria focus in the country. Anopheles (Anopheles) maculipennis labranchiae and Anopheles (Cellia) sergentii, the major vectors of malaria in Morocco, are still presents but their anthropothic index was low and no parasite positive samples were detected. An. labranchiae was very rare: only 34 females were caught over all the study period. The human biting rate was nil and none of its blood meal was human. An. sergenti was more abundant but its low human aggressiveness and its zoophilic behaviour would not attribute to this species an important vectorial capacity. Thus, the receptivity of Chefchaouen province, the region of the last malaria focus in Morocco, under the current vector control measures undertaken by Public Health services, is low and despite the likely presence of Plasmodium vivax gametocyte carriers, the malariogenic potential appears to be low and the risk of malaria resumption is, at this time, unimportant

Review of the Urinary Schistosomiasis Control in Morocco (1960–2018)

The purpose of this study is to describe the epidemiological profile and evolution of urinary schistosomiasis in Morocco, from the first confirmed case in 1960 until disease elimination, and control snails. During this period, 129,526 cases were recorded in Morocco. A majority of cases were reported in Agadir province (25%), Errachidia (18%), and Beni Mellal (13%). Other cases have been reported in the other provinces. Activities within the National Schistosomiasis Control Programme for more than three decades were focused in priori on screening in schools located in high-risk communities, treatment program, surveillance of snails in water bodies, and mollusciciding. Then, the goal of eliminating the transmission of schistosomiasis has been reached in 2004. Sixteen years later, no indigenous cases were detected in Morocco, and only 25 residual cases (resulting from bilharziasis previously treated) are detected, such as in Tata ( 40%), Errachidia (16%), and (12%) in Marrackesh. Similarly, recent national studies conducted on children and the snail reservoir hosts have indicated that no human and molluscs are currently infected with Schistosoma haematobium. Actually, timely investigation and management of imported cases has been implemented to prevent the reintroduction of the disease. The Ministry of Health is planning to implement final confirmatory surveys before requesting WHO to proceed with the formal verification process

Risque de réémergence du paludisme au Maroc Étude de la capacité vectorielle d’Anopheles labranchiae dans une zone rizicole au nord du pays

Dans le but d’estimer le risque de réintroduction du paludisme au Maroc, nous avons analysé le potentiel paludogène d’une zone rizicole au nord du pays. Nos résultats ont montré que la capacité vectorielle d’An. labranchiae, vecteur du paludisme au Maroc, était particulièrement élevée pendant la période estivale qui correspond à la période de culture du riz. Le risque d’une reprise de la transmission du paludisme autochtone est élevé du fait de l’éventuelle présence de porteurs de parasite dans le dernier foyer de paludisme limitrophe de la zone d’étude. Le risque d’une introduction du paludisme tropical est faible, vu la faible vulnérabilité de la région et la compétence de ses vecteurs, considérée comme faible. Toutefois, ce risque doit faire l’objet d’une grande attention

Risque de réémergence du paludisme au Maroc Étude de la capacité vectorielle d’

Dans le but d’estimer le risque de réintroduction du paludisme au Maroc, nous avons analysé le potentiel paludogène d’une zone rizicole au nord du pays. Nos résultats ont montré que la capacité vectorielle d’An. labranchiae, vecteur du paludisme au Maroc, était particulièrement élevée pendant la période estivale qui correspond à la période de culture du riz. Le risque d’une reprise de la transmission du paludisme autochtone est élevé du fait de l’éventuelle présence de porteurs de parasite dans le dernier foyer de paludisme limitrophe de la zone d’étude. Le risque d’une introduction du paludisme tropical est faible, vu la faible vulnérabilité de la région et la compétence de ses vecteurs, considérée comme faible. Toutefois, ce risque doit faire l’objet d’une grande attention

Mapping Malaria Transmission Risk in Northern Morocco Using Entomological and Environmental Data

International audienceMalaria resurgence risk in Morocco depends, among other factors, on environmental changes as well as the introduction of parasite carriers. The aim of this paper is to analyze the receptivity of the Loukkos area, large wetlands in Northern Morocco, to quantify and to map malaria transmission risk in this region using biological and environmental data. This risk was assessed on entomological risk basis and was mapped using environmental markers derived from satellite imagery. Maps showing spatial and temporal variations of entomological risk for Plasmodium vivax and P. falciparum were produced. Results showed this risk to be highly seasonal and much higher in rice fields than in swamps. This risk is lower for Afrotropical P. falciparum strains because of the low infectivity of Anopheles labranchiae, principal malaria vector in Morocco. However, it is very high for P. vivax mainly during summer corresponding to the rice cultivation period. Although the entomological risk is high in Loukkos region, malaria resurgence risk remains very low, because of the low vulnerability of the area