Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2012 Jun 21:5:127.
doi: 10.1186/1756-3305-5-127.

Population dynamics of Anopheles gambiae s.l. in Bobo-Dioulasso city: bionomics, infection rate and susceptibility to insecticides

Roch K Dabiré  1 , Moussa Namountougou, Simon P Sawadogo, Lassina B Yaro, Hyacinthe K Toé, Ali Ouari, Louis-Clément Gouagna, Frédéric Simard, Fabrice Chandre, Thierry Baldet, Chris Bass, Abdoulaye Diabaté
Affiliations

Population dynamics of Anopheles gambiae s.l. in Bobo-Dioulasso city: bionomics, infection rate and susceptibility to insecticides

Roch K Dabiré et al. Parasit Vectors. .

Abstract

Background: Historical studies have indicated that An. gambiae s.s. is the predominant malaria vector species in Bobo-Dioulasso the second biggest city of Burkina Faso (West Africa). However, over the last decade, An. arabiensis appears to be replacing An. gambiae s.s. as the most prevalent malaria vector in this urban setting. To investigate this species transition in more detail the present study aims to provide an update on the malaria vector composition in Bobo-Dioulasso, and also the Plasmodium infection rates and susceptibility to insecticides of the local An. gambiae s.l. population.

Methods: An entomological survey was carried out from May to December 2008 in Dioulassoba and Kodeni (central and peripheral districts respectively), which are representative of the main ecological features of the city. Sampling consisted of the collection of larval stages from water bodies, and adults by monthly indoor residual spraying (IRS) using aerosol insecticides. Insecticide susceptibility tests were performed using the WHO filter paper protocol on adults emerged from larvae. PCR was used to determine vector species and to identify resistance mechanisms (kdr and ace-1(R)). The Plasmodium infection rate was estimated by ELISA performed on female mosquitoes collected indoors by IRS.

Results: An. arabiensis was found to be the major malaria vector in Bobo-Dioulasso, comprising 50 to 100% of the vector population. The sporozoite infection rate for An. arabiensis was higher than An. gambiae s.s. at both Dioulassoba and Kodeni. An. gambiae s.l. was resistant to DDT and cross-resistant to pyrethroids at the two sites with higher levels of resistance observed in An. gambiae s.s. than An. arabiensis. Resistance to 0.1% bendiocarb was observed in the An. gambiae s.s. S form but not the M form or in An. arabiensis. The L1014F kdr mutation was detected in the two molecular forms of An. gambiae s.s. at varying frequencies (0.45 to 0.92), but was not detected in An. arabiensis, suggesting that other mechanisms are involved in DDT resistance in this species. The ace-1(R) mutation was only detected in the S molecular form and was observed at the two sites at similar frequency (0.3).

Conclusions: Over the last ten years, An. arabiensis has become the major malaria vector in Bobo-Dioulasso city where it was formerly present only at low frequency. However, the ecological determinant that enhances the settlement of this species into urban and peri-urban areas of Bobo-Dioulasso remains to be clarified. The impact of the changing An. gambiae s.l. population in this region for vector control including resistance management strategies is discussed.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Monthly population dynamics ofAnopheles gambiae s.l.in Kodeni.
Figure 2
Figure 2
Monthly population dynamics ofAnopheles gambiae s.l.in Dioulassoba.
See this image and copyright information in PMC

References

    1. Hunt RH, Coetzee M, Fettene M. The Anopheles gambiae complex: A new species from Ethiopia. Trans R Soc Trop Med Hyg. 1998;92:231–235. doi: 10.1016/S0035-9203(98)90761-1. - DOI - PubMed
    1. Della Torre A, Tu Z, Petrarca V. On the distribution and genetic differentiation of Anopheles gambiae ss molecular forms. Insect Bioch Mol Biol. 2005;35:7055–7069. - PubMed
    1. Govella NJ, Chaki PP, Mpangile JM, Gerry F, Killeen GF. Monitoring mosquitoes in urban Dar es Salaam: Evaluation of resting boxes, window exit traps, CDC light traps, Ifakara tent traps and human landing catches. Parasites & Vectors. 2011;4:40. doi: 10.1186/1756-3305-4-40. - DOI - PMC - PubMed
    1. Touré YT, Petrarca V, Traoré SF, Coulibaly A, Maiga HM, Sangaré O, Sow M, Di Decco MA, Coluzzi M. The distribution and inversion polymorphism of chromosomally recognised taxa of the Anopheles gambiae complex in Mali, West Africa. Parassitologia. 1998;40:477–511. - PubMed
    1. Costantini C, Ayala D, Guelbeogo WM, Pombi M, Some CY, Bassole IHN, Ose K, Fotsing JM, Sagnon NF, Fontenille D, Besansky N, Simard F. Living at the edge: biogeographic patterns of habitat segregation conform to speciation by niche expansion in Anopheles gambiae. BMC Ecol. 2009;9:16. doi: 10.1186/1472-6785-9-16. - DOI - PMC - PubMed

Publication types

LinkOut - more resources