Aedes (Diptera: Culicidae) vectors of arboviruses in Mayotte: distribution area and breeding sites by Leïla BAGNY PhD student

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1 Aedes (Diptera: Culicidae) vectors of arboviruses in Mayotte: distribution area and breeding sites by Leïla BAGNY PhD student Directed by S. QUILICI (CIRAD) and D. FONTENILLE (IRD)

2 Introduction Mayotte Epidemics of Chikungunya in with 38% of populations affected (Cire Mayotte)

Introduction Culicidae fauna Ae. simpsoni Ae. aegypti Ae.

org 35 species of Culicidae recorded : Anopheles, Culex,

and Aedes (Brunhes 1978) Stegomyia species: Ae. vittatus, Ae.

3 Introduction Culicidae fauna Ae. simpsoni Ae. aegypti Ae. albopictus 35 species of Culicidae recorded : Anopheles, Culex, Eretmapodites, Mansonia, Orthopodomyia, Ficalbia, Uranotaenia and Aedes (Brunhes 1978) Stegomyia species: Ae. vittatus, Ae. simpsoni complex, Ae. aegypti (Brunhes 1978) 2001: first record of Ae. albopictus on the island (Girod 2004)

4 Introduction Aedes albopictus in the world Ae. aegypti Invasive since 30 years Native Introduced Intercepted (Tatem et al. 2006) Species mentionned as rural in its native area also in some invaded areas (like Brazil, Florida, Puerto Rico )

albopictus in Mayotte Is there an impact of the introduction of Ae.

5 Introduction Objectives Update of Aedes (Stegomyia) distribution, 7 years after the first record of Ae. albopictus in Mayotte Is there an impact of the introduction of Ae. albopictus on resident species? What are the effects of the introduction of this species on public health?

wrbu.org Larval identification Only breeding sites with Aedes

6 Field survey Mat & Meth 2 seasons 6 locations 3 habitats 10 houses in urban and suburban areas 1 ha in rural areas Larval identification Only breeding sites with Aedes spp. Dzoumogné Labattoir Lab Mtsapéré Chiconi Bandrélé Mtsamoudou

Results Breeding sites surveyed 100% 80% 60% 40% 20% 0% Leaf axillae Bamboo stumps

Barrels Pots Buckets Tires Earthenware jars Others Total Ae. albopictus Ae.

aegypti, often share the same breeding site Ae.

7 Results Breeding sites surveyed 100% 80% 60% 40% 20% 0% Leaf axillae Bamboo stumps Tree hole Rock holes Dead leaves Coconut shells Bottles Tin cans Small wastes Cans Barrels Pots Buckets Tires Earthenware jars Others Total Ae. albopictus Ae. aegypti Ae. albopictus - Ae. aegypti Ae. lilii Ae. albopictus and Ae. aegypti, often share the same breeding site Ae. albopictus more in artificial breeding sites Ae. aegypti more in natural breeding sites Ae. lilii rare and more in natural breeding sites

8 Leaf axilla (9; 8) Bamboo stumps (9; 7) Snail shells (1; 1) Tree holes (13; 4) Rock holes (6; 2) Dead leaves on ground (21; 9) Coconut shells (31; 22) Broken bottles (9; 14) Tin cans (12; 15) Small plastic wastes(18; 17) Cans (19; 19) Barrels (26; 59) Pots (38; 47) Buckets (23; 42) Used tires (4; 10) Earthenware jars (1; 5) Others (18; 18) Leaf axilla (1; 1) Bamboo stumps (0; 2) Snail shells (0; 0) Tree holes (1; 1) Rock holes (1; 0) Dead leaves on ground (12; 1) Coconut shells (8; 8) Broken bottles (1; 4) Tin cans (2; 4) Small plastic wastes (6; 10) Cans (6; 4) Barrels (10; 32) Pots (20; 14) Buckets (4; 21) Used tires (0; 1) Earthenware jars (0; 4) Others (4; 6) Results Average productivity of breeding sites 140 LARVAE 10 PUPAE Ae. albopictus Ae. aegypti 8 Natural sites 80 Conclusion Storage containers Larvae Ae. albopictus >>> Larvae Ae. aegypti Pupae Ae. albopictus > Pupae Ae. aegypti Pupae Ae. albopictus < Pupae Ae. aegypti

9 Dzoumogné Estimated relative frequency of species in rural (R), suburban (S) and urban (U) habitats Labattoir Mtsapéré Chiconi Location: Bandrélé Bandrélé Bandrélé Mtsamoudou Rainy season 0,8 0,7 Dry season 0,9 0,8 R U 0,7 0,6 U 0,5 0,6 R S 0,5 S 0,4 0,4 S 0,3 U 0,2 0,1 S Ae. aegypti 0,1 R more in rural areas Ae. aegypti + Ae.albopictus R 0,2 R 0 S 0,3 Ae. albopictus more in suburban areas S U 0 Ae. aegypti Ae. aegypti + Ae.albopictus Ae. albopictus more in urban areas

Conclusion Aedes spp. distribution in Mayotte Ae.

sites Poor implication in arboviruses emergence

aegypti : Rural Natural breeding sites Ae.

10 Conclusion Aedes spp. distribution in Mayotte Ae. lilii : Uncommon Very rural Natural breeding sites Poor implication in arboviruses emergence in Mayotte Ae. aegypti : Rural Natural breeding sites Ae. albopictus : Rapid spread in Mayotte Artificial breeding sites Occurrence in urban areas

(Williamson 1996; Juliano 2004) Further studies are

11 Conclusion Effect on resident species? Displacement of Ae. aegypti to rural habitats by Ae. albopictus is ongoing in Mayotte Probably due to competitive interactions between these 2 species (Williamson 1996; Juliano 2004) Further studies are required to identify mechanisms involved in the eventual competition

major vector implicated in the Chikungunya epidemics in 2005-2006 because of its dominance in inhabitated areas and its

12 Conclusion Effect on public health? It may have modify arboviruses transmission in Mayotte like in other countries (Mitchell 1995; Lounibos 2002) Probably the major vector implicated in the Chikungunya epidemics in because of its dominance in inhabitated areas and its good transmission competence for this virus (Vazeille 2007) As it preferentially colonizes storage containers a mechanic control can be suggested to reduce the populations of this vector Bagny et al submitted

13 Thank you for your attention

Duane J. Gubler, ScD Professor and Founding Director, Signature Research Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore

Duane J. Gubler, ScD Professor and Founding Director, Signature Research Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore AGENDA Other arboviruses with the potential for urban