Comparative role of Aedes albopictus and Aedes aegypti in the emergence of Dengue and Chikungunya in central Africa.

Christophe Paupy (1, 2) , Benjamin Ollomo (3) , Basile Kamgang (1, 2) , Sara Moutailler (4) , Dominique Rousset (5) , Maurice Demanou (5) , Jean-Pierre Hervé (2) , Eric M. Leroy (3, 6) , Frédéric Simard (1, 2)

1 Caractérisation et contrôle des populations de vecteurs
2 OCEAC - Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale
3 CIRMF - Centre International de Recherches Médicales de Franceville
4 Génétique Moléculaire des Bunyavirus
5 Centre Pasteur du Cameroun
6 Institut de Recherche pour le Développement (IRD), Franceville, Gabon

Since its discovery in Nigeria in 1991, Aedes albopictus has invaded much of Central Africa, a region where Ae. aegypti also occurs. To assess the relationship between the invasion by Ae. albopictus and the recent emergence of dengue virus (DENV) and chikungunya virus (CHIKV), we undertook vector competence experiments on populations collected from Cameroon and conducted field investigations during concurrent epidemics of DENV and CHIKV in Gabon. Overall, infection and dissemination rates were not significantly different between Ae. albopictus and Ae. aegypti when exposed to titers of 10(8.1) mosquito infectious dose 50/mL and 10(7.5) plaque forming units/mL of DENV type 2 and CHIKV, respectively. Field investigations showed that Ae. albopictus readily bit man, was abundant, and outnumbered Ae. aegypti to a large extent in Gabon, particularly in suburban environments. Nevertheless, Ae. aegypti was predominant in the more urbanized central parts of Libreville. In this city, CHIKV and DENV were detected only in Ae. albopictus. These data strongly suggest that Ae. albopictus acted as the major vector of both viruses in Libreville in 2007, impacting on the epidemiology of DENV and CHIKV in this area.

Domaines: Virologie

Christophe Paupy, Benjamin Ollomo, Basile Kamgang, Sara Moutailler, Dominique Rousset, et al.. Comparative role of Aedes albopictus and Aedes aegypti in the emergence of Dengue and Chikungunya in central Africa.. Vector-Borne and Zoonotic Diseases, 2010, 10 (3), pp.259-66. ⟨10.1089/vbz.2009.0005⟩. ⟨pasteur-00542428⟩