The mosquito Aedes (Aedimorphus) vexans arabiensis as a probable vector bridging the West Nile virus between birds and horses in Barkedji (Ferlo, Senegal).

This study identifies Aedesvexans arabiensis, a type of mosquito , as a probable link in the transmission of West Nile virus from birds to horses in the Ferlo area of Senegal. The mosquito species was found to frequently feed on both birds and horses, indicating its potential as a bridge for the virus between these two species.

Methodology and Data Collection

• The researchers involved in the study utilized nets or aspirators for active capture of adult female mosquitoes of the species Aedes vexans arabiensis Patton during the years 2003 and 2004.
• The collection was performed in the vegetation bordering temporary ponds located in Barkedji, an area within Ferlo in Senegal.
• 241 blood-fed female mosquitoes were caught, dissected, and their gut content was collected. The content was adsorbed onto a Whatman filter paper to prepare for further analysis.

Bloodmeal Analysis

• Once the gut content of mosquitoes was collected, it was subjected to an enzyme-linked immunosorbent assay (ELISA), a standard technique used for detecting and measuring antibodies in a blood sample.
• Using ELISA, researchers were able to determine the origin of the bloodmeal – in other words, they could find out which type of animal the mosquito had fed on.

Results and Conclusions

• The majority of the blood meals were traced back to mammals, including horses, which made up 35.7% of the total. However, blood from birds was also detected in 10% of the bloodmeals.
• Moreover, 42% of the bloodmeals demonstrated a mixture of blood from both horses and birds. This suggests that Ae. v. arabiensis mosquitoes feed on both species, therefore acting as a possible conduit for the transfer of West Nile virus from birds, the natural hosts of the virus, to horses.
• The results of this study point to Ae. v. arabiensis as a probable vector for West Nile virus transmission between birds and horses, defining its role in the disease’s epidemiology within the Ferlo area of Senegal.