Journal of Vector Ecology. Rainfall patterns and population dynamics of Aedes (Aedimorphus) vexans arabiensis, Patton 1905 (Diptera: Culicidae), a potential vector of Rift Valley Fever virus in Senegal [texte imprimé] / B Mondet, Auteur ; A. Diaité, Auteur ; .J A. Ndione, Auteur ; A G Fall, Auteur ; V chevallier, Auteur ; R. Lancelot, Auteur ; M Ndiaye, Auteur ; N Ponçon, Auteur . - Dakar (PRH, Sénégal) : ISRA/LNERV, 2004 . - 05p. : ref,;. Langues : Anglais ( eng) Catégories : | SCIENCES, PRODUCTION ET PROTECTION ANIMALES
| Mots-clés : | Population Dynamique, Variation Pluviométrique, Fièvre de la Vallée du Rift, Virus, Sénégal | Index. décimale : | L730-Maladie des animaux | Résumé : | The importance of rainfall for the development of Aedes vexans arabiensis populations, one of the potential
vectors of Rift Valley Fever in West Africa, was demonstrated in a two-year follow-up study conducted in the Ferlo region of
Senegal. In 2003, the rainy season began with heavy rains and, as a result, temporary ponds, the breeding places for mosquitoes,
were flooded at their maximum level immediately. In such conditions, Aedes vexans arabiensis populations are abundant at
the very beginning of the season, when the majority of eggs in quiescence are flooded. Females, hatching from eggs laid the
year before, quickly lay eggs on the pond’s wet soil, which will undergo dormancy as the water level goes down. Rainless
periods longer than seven days, the time needed for embryogenesis, followed by significant rainfall, will result in the hatching
of very large numbers of new eggs. Thus, several generations of adults may exist during the same rainy season. Because of
potential vertical transmission of Rift Valley Fever virus in Aedes species, viral transmission and disease risk can appear as
early as the beginning of the rainy season and if late rains occur, at the end of the season. This dynamic maximizes the virus’
chance to persist from one year to another, thus facilitating endemisation of Rift Valley Fever in areas where Aedes vexans
arabiensis exists. Journal of Vector Ecology 30 (1): 102-106. 2005 |
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