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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.

Malaria 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.

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 anthropopathic 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.