Arbovirus prevalence in mosquitoes, Kenya

Area of Science:

• Medical Entomology
• Arbovirology
• Public Health

Background:

• Limited research exists on Kenyan mosquito species harboring arboviruses.
• Arboviruses pose a significant public health threat, necessitating vector surveillance.

Purpose of the Study:

• To identify mosquito species and assess arbovirus prevalence in Kenya during the 2006-2007 Rift Valley fever outbreak.
• To compare arbovirus infection rates in mosquitoes between rural and urban settings.

Main Methods:

• Collection of exophilic mosquitoes from Gumarey (rural) and Sogan-Godud (urban) in North Eastern Province, Kenya.
• Mosquitoes (n=920) were pooled and tested for Rift Valley fever virus and West Nile virus using molecular methods.
• Analysis of mosquito species composition, with a focus on the genus Culex.

Main Results:

• The genus Culex comprised 75% of trapped mosquitoes.
• 22% of mosquito pools tested positive for Rift Valley fever virus, 18% for West Nile virus, and 3% for both.
• No significant difference in minimum infection rates was observed between rural and urban locations.

Conclusions:

• The study confirms the presence of abundant mosquito vectors capable of propagating arboviral infections in Kenya.
• High arbovirus positivity rates underscore the ongoing risk of transmission, particularly during outbreaks.
• Findings emphasize the need for enhanced mosquito and arbovirus surveillance programs in affected regions.