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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.

IntroductionOn 4 November 2010, the Ministry of Health of the Republic of Congo declared a poliomyelitis outbreak in Pointe-Noire, the eastern economic capital. We conducted an outbreak investigation to describe the epidemic and estimate vaccination coverage to better understand virus spread.MethodsWe collected clinical, demographic and geographic data about cases and vaccination policies from local health authorities. Cases were defined as residents of Pointe-Noire of any age, diagnosed with acute flaccid paralysis since 1 October 2010. We implemented a cross-sectional survey in a socially heterogeneous affected neighbourhood (representing 9.5% of the city population), selected from the Loandjili district (highest district attack rate: 71.6 cases per 100 000) following expert consultation.ResultsFrom 1 October to 20 December 2010, 446 cases of acute flaccid paralysis were reported to health authorities (case fatality ratio: 41.3%). Males accounted for 68% of the cases, and 57.4% were between 15 and 24 years of age. Vaccination coverage in the surveyed population for one or more doses of oral polio vaccine was 55.5% on average and decreased with age to 33.5% for individuals older than 30. Sanitary conditions were poor to medium with latrines commonly shared between households (57.4%).ConclusionPoor vaccination coverage led to a large susceptible population, particularly in young adults and spread was further facilitated by poor sanitary conditions. Moreover, polio causes more severe clinical symptoms among older age groups, which explains the high case-fatality ratio. To prevent similar outbreaks in other countries, supplementary vaccination activities should punctually target older age groups.