Anopheles gambiae distribution and insecticide resistance in the cities of Douala and Yaoundé (Cameroon): influence of urban agriculture and pollution

Malaria Journal

Research

Serge Zebaze Togouet¹  Parfait Awono-Ambene²  Billy Tene Fossog³  Benjamin Menze Djantio³  Cyrille Ndo³  Carlo Costantini⁴  Christophe Antonio-Nkondjio⁵  Charles S Wondji⁶  Hilary Ranson⁶ 

[1] Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon;Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon;Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon;Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon;Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon;Institut de Recherche pour le Développement (IRD), P.O. Box 64501, UR 016, 911, avenue Agropolis, 34394, Montpellier cedex 5, France;Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon;Vector group, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK;Vector group, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, Liverpool, UK;

关键词: Malaria;    Malathion;    Malaria Vector;    Breeding Site;    Insecticide Resistance;   

DOI  :  10.1186/1475-2875-10-154

 received in 2011-03-08, accepted in 2011-06-08,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundUrban malaria is becoming a major health priority across Africa. A study was undertaken to assess the importance of urban pollution and agriculture practice on the distribution and susceptibility to insecticide of malaria vectors in the two main cities in Cameroon.MethodsAnopheline larval breeding sites were surveyed and water samples analysed monthly from October 2009 to December 2010. Parameters analysed included turbidity, pH, temperature, conductivity, sulfates, phosphates, nitrates, nitrites, ammonia, aluminium, alkalinity, iron, potassium, manganese, magnesium, magnesium hardness and total hardness. Characteristics of water bodies in urban areas were compared to rural areas and between urban sites. The level of susceptibility of Anopheles gambiae to 4% DDT, 0.75% permethrin, 0.05% deltamethrin, 0.1% bendiocarb and 5% malathion were compared between mosquitoes collected from polluted, non polluted and cultivated areas.ResultsA total of 1,546 breeding sites, 690 in Yaoundé and 856 in Douala, were sampled in the course of the study. Almost all measured parameters had a concentration of 2- to 100-fold higher in urban compare to rural breeding sites. No resistance to malathion was detected, but bendiocarb resistance was present in Yaounde. Very low mortality rates were observed following DDT or permethrin exposure, associated with high kdr frequencies. Mosquitoes collected in cultivated areas, exhibited the highest resistant levels. There was little difference in insecticide resistance or kdr allele frequency in mosquitoes collected from polluted versus non-polluted sites.ConclusionThe data confirm high selection pressure on mosquitoes originating from urban areas and suggest urban agriculture rather than pollution as the major factor driving resistance to insecticide.

【 授权许可】

CC BY   
© Antonio-Nkondjio et al; licensee BioMed Central Ltd. 2011