Entomological Co-infections of Arboviruses: Dengue and Chikungunya Viruses along the Coastline of Kenya

Arthropod-borne disease outbreaks as a result of pathogen influx including arboviruses transmitted by strains of Aedes species occur periodically in varying spots in Kenya. However, there has been paucity of documented information on the Aedes species involved in transmission of different haplotypes of arboviruses. This study assessed for concomitant infection of arboviruses in different vectors. Aedes species were sampled by Bio gent sentinel trap. Mosquitoes were stunned at 4°C for 5 minutes; sorted according to site, species and sex. RNA was extracted using Trizole®. cDNA was generated using one step real time PCR. Proportions of vectors and arboviruses were analyzed by R-statistics. A total of 37, 220 mosquitoes of Aedes species were analyzed. Vectors were: Aedes aegypti formosus (23,265=62.5%), Aedes aegypti aegypti (4,931=13.2%), Aedes mcintoshi (3,557=9.56%), Aedes ochraceus (2,156=5.79%), Aedes pembaensis (2,049=5.51%), Aedes tricholabis (487=1.31%), Aedes albicosta (415=1.11%), Aedes fulgens (200=0.54%) and Aedes fryeri (160=0.43%). Dengue virus (DENV) had highest entomological infections at 79% (n=1910) while Chikungunya (CHIKV) at 21%. DENV-2 had the highest frequency at 54%, while DENV-4 with the least frequency at 6%. Only ECSA genotype of CHIKV was present. Concomitant infections of arboviral haplotypes in different clades of Aedes species occur along the coastal region. Aedes aegypti aegypti is incubates all serotypes of DENV and genotype of CHIK viruses thus the major vectors of arboviruses. This information is important as it gives knowledge on areas at high risk for arboviral disease outbreaks. Consecutively, up scaled survey and implementation of control and prevention measures taken appropriately.