Jonathan Chome Ngala¹ , Margaret Wangui Muturi¹ , Charles M. Mbogo² , Martin K. Rono^2,3

1 Kenyatta University, School of Medicine, Department of Medical Laboratory Sciences, P.O. Box 43844, Nairobi, Kenya
2 Kenya Medical Research Institute, Centre for Geographical Medicine Research-Coast, P.O. Box 230-80108, Kilifi, Kenya
3 Pwani University Bioscience Research Centre (PUBReC), Pwani University, P.O. Box 195-80108, Kilifi, Kenya
Author    Correspondence author
Journal of Mosquito Research, 2018, Vol. 8, No. 5   
Received: 20 Sep., 2018    Accepted: 31 Oct., 2018    Published: 30 Nov., 2018

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

A surge in outbreaks of arboviral infections has been documented in spots along Kenyan Coast. However, there is paucity of documented information on distribution of Aedes species involved in transmission of arboviruses and their infection status. This study determined spatial and temporal distribution of Aedes species and their infection status for Dengue (DENV) and Chikungunya (CHIKV) arboviruses along the coastline of Kenya during dry and wet seasons. Indoor and outdoor sampling of adults Aedes species was done using Biogent Sentinel trap baited with solid carbon dioxide and aspiration technique. Samples were identified to sex and species by morphological features. Sites coordinates were noted by GPS with maps drawn using geomap and ggplot packages. RNA from the samples was extracted using Trizole®. cDNA was generated from RNA using one step real time PCR for identification of arboviruses. Proportions of arboviruses were analyzed by R-statistics. A total of 37,220 Aedes mosquitoes were collected and pooled in pools of 20 mosquitoes. Aedes species identified and their respective proportions were: Aedes aegypti formosus (62.5%), Aedes aegypti aegypti (13.2%), Aedes mcintoshi (9.56%), Aedes ochraceus (5.79%), Aedes pembaensis (5.51%), Aedes tricholabis (1.31%), Aedes albicosta (1.11%), Aedes fulgens (0.54%) and Aedes fryeri (0.43%). Aedes aegypti aegypti had not been identified along the coastline in previous studies. The Aedes mosquito sample sizes and their distribution along the coastline were insignificantly different between the two seasons. Vector infections by DENV and CHIKV were insignificantly different between the seasons. In this study, DENV-4 was identified in Aedes species along the coastline of Kenya. Our data confirms the previous reports for increased risk of infection during wet seasons and further identifies other regions with increased risk of arboviral transmission along Coastal Kenya. This information is important as it gives knowledge on areas at high risk for arboviral disease outbreaks in cases where human-vector contacts occur. Consecutively, up scaled survey and implementation of control and prevention measures should be taken appropriately.

Mosquito; Seasonal variability; Meteorology; Dengue; Pune; India; Chikungunya