Diversity and utilization of indigenous wild edible plants and their contribution to food security in Turkana County, Kenya

Introduction Indigenous Wild edible plants (IWEPs) are consumed daily in some form by at least one in seven people worldwide. Many of them are rich in essential nutrients with the potential for dietary and nutrition improvement particularly for poor households. They are, however, often overlooked. This study investigated diversity, consumption frequency, and perceptions of IWEPs and the contribution they make to the food security of communities in Turkana County, northern Kenya. Our findings are aimed at stimulating targeted discussions among stakeholders involved in food security programs on best way to overcome the poverty stigma associated with IWEPs consumption and to promote their utilization for food security, nutritional and dietary improvement, and enhanced community resilience. Methods Applying a mixed-methods approach, we collected data using 12 gender-disaggregated focus group discussions and a questionnaire applied to a random sample of 360 households. Results and Discussion Participants identified 73 IWEPs, of which 24 were consumed in the preceding six months by 48.5% of households. Almost all surveyed households (96%) were classified as severely food insecure, and food insecurity did not differ significantly between households that consumed IWEPs and those that did not. Our results indicate that more IWEPs consumers than non-consumers reported eating foods they had not wanted to consume to cope with food scarcity, as well as having to eat fewer meals than normal. Just over half of the respondents (57.1%) held positive attitudes towards IWEPs, which was positively associated with a higher likelihood of IWEPs consumption. Long distances to harvest sites, lack of knowledge about the plants, their seasonality, and how to cook them appetizingly, coupled with overall unfavorable perceptions, are probable reasons for non-consumption of IWEPs among the survey respondents. In line with other studies cited on wild foods, we conclude that IWEPs have the potential to bridge food and nutritional deficits in food insecure households in the study area, although currently their consumption remains limited. Given this potential, further analysis of IWEPs’ nutritional composition and restoration of wild edible foods to local areas should be given priority, as well as interventions that help to overcome the challenges to their consumption and promote their wider use

Disparity between leaf and root symptoms and crop losses associated with cassava brown streak disease in four countries in eastern Africa

Cassava brown streak disease is endemic to the coastal regions of East Africa, and from around 2004, the disease resurged and became epidemic in the Great Lakes Region, where it continues to spread. In both these areas, cassava brown streak disease (CBSD) leaf symptoms occur at high incidences. However, it is the associated symptom of root rot (necrosis) in the starch-bearing tissues that renders the root unfit for human consumption. Because the extent of root necrosis is not known until the crop is harvested and surveys require destructive sampling, root symptoms are much less frequently assessed than are the above-ground symptoms on the leaves and stems. Surveys were undertaken in selected villages in Tanzania, Kenya, Uganda and Malawi to assess the incidence of CBSD leaf symptoms and the incidence and severity of root symptoms, to estimate the impact of the disease on household food security and on cassava processing. CBSD leaf symptoms were recorded at high incidences (40–90% in individual fields) in all fields visited throughout East Africa, but root necrosis incidence was lower than would be expected from the high incidence of leaf symptoms. Severe root necrosis at high incidence was found only on a few varieties, usually grown to a limited extent. It appears that varieties that are prone to root necrosis are being abandoned in favour of those with a lower propensity to develop root necrosis after infection by the virus

Vector competence of populations of Aedes aegypti from three distinct cities in Kenya for chikungunya virus

BACKGROUND : In April, 2004, chikungunya virus (CHIKV) re-emerged in Kenya and eventually spread to the islands in the Indian Ocean basin, South-East Asia, and the Americas. The virus, which is often associated with high levels of viremia in humans, is mostly transmitted by the urban vector, Aedes aegypti. The expansion of CHIKV presents a public health challenge both locally and internationally. In this study, we investigated the ability of Ae. aegypti mosquitoes from three distinct cities in Kenya; Mombasa (outbreak prone), Kisumu, and Nairobi (no documented outbreak) to transmit CHIKV. METHODOLOGY/PRINCIPAL FINDINGS : Aedes aegypti mosquito populations were exposed to different doses of CHIKV (105.6±7.5 plaque-forming units[PFU]/ml) in an infectious blood meal. Transmission was ascertained by collecting and testing saliva samples from individual mosquitoes at 5, 7, 9, and 14 days post exposure. Infection and dissemination were estimated by testing body and legs, respectively, for individual mosquitoes at selected days post exposure. Tissue culture assays were used to determine the presence of infectious viral particles in the body, leg, and saliva samples. The number of days post exposure had no effect on infection, dissemination, or transmission rates, but these rates increased with an increase in exposure dose in all three populations. Although the rates were highest in Ae. aegypti from Mombasa at titers 106.9 PFU/ml, the differences observed were not statistically significant (χ2 1.04, DF = 1, P 0.31). Overall, about 71% of the infected mosquitoes developed a disseminated infection, of which 21% successfully transmitted the virus into a capillary tube, giving an estimated transmission rate of about 10% for mosquitoes that ingested 106.9 PFU/ml of CHIKV. All three populations of Ae. aegypti were infectious as early as 5±7 days post exposure. On average, viral dissemination only occurred when body titers were 104 PFU/ ml in all populations. CONCLUSIONS/SIGNIFICANCE : Populations of Ae. aegypti from Mombasa, Nairobi, and Kisumu were all competent laboratory vectors of CHIKV. Viremia of the infectious blood meal was an important factor in Ae. aegypti susceptibility and transmission of CHIKV. In addition to viremia levels, temperature and feeding behavior of Ae. aegypti may also contribute to the observed disease patterns.The National Institutes of Health (NIH), Grant No. 1R01AI099736-01A1 to RS, UK's Department for International Development (DFID), Swedish International Development Cooperation Agency (Sida), the Swiss Agency for Development and Cooperation (SDC) and the Kenyan Government.http://www.plosntds.orgam2017Medical Virolog

Knowledge, Attitude and Practice in Water Resources Management among Smallholder Irrigators in the Tsavo Sub-Catchment, Kenya

The rising demand for food production in a changing climate impacts water resources negatively in semi-arid agro-ecosystems. In the Tsavo sub-catchment of Kenya, this is compounded by a surging population and expansion of cropping as a land use; leading to increased abstraction of surface water resources and deterioration of related ecosystem services. The impact of increased abstraction is more profound during water stress seasons when stream-flow levels are low. While water policies have incorporated a requirement for environmental flows, unregulated abstractions persist suggesting an inherent challenge. Drawing on a sample of 279 households, we analysed farmers’ engagement in water resources management and explored how this can inform water resource planning. Seasonal water scarcity and user conflicts were the major challenges experienced by the farmers. Ordinal and logistic regression models show that knowledge, attitude and practices were culture-dependent being impacted by educational attainment, level of income, access to extension and membership to local networks. Attitude and practice were further influenced by land tenure and farm distance to water sources. Since knowledge of water management issues informed attitudes and practices, improved awareness and targeted extension support are necessary in the development and implementation of policy decisions on water resources management

Vector competence of Aedes bromeliae and Aedes vitattus mosquito populations from Kenya for chikungunya virus.

BACKGROUND:Kenya has experienced outbreaks of chikungunya in the past years with the most recent outbreak occurring in Mandera in the northern region in May 2016 and in Mombasa in the coastal region from November 2017 to February 2018. Despite the outbreaks in Kenya, studies on vector competence have only been conducted on Aedes aegypti. However, the role played by other mosquito species in transmission and maintenance of the virus in endemic areas remains unclear. This study sought to determine the possible role of rural Aedes bromeliae and Aedes vittatus in the transmission of chikungunya virus, focusing on Kilifi and West Pokot regions of Kenya. METHODS:Four day old female mosquitoes were orally fed on chikungunya virus-infected blood at a dilution of 1:1 of the viral isolate and blood (10(6.4) plaque-forming units [PFU]/ml) using artificial membrane feeder (Hemotek system) for 45 minutes. The engorged mosquitoes were picked and incubated at 29-30°C ambient temperature and 70-80% humidity in the insectary. At days 5, 7 and 10 post-infection, the mosquitoes were carefully dissected to separate the legs and wings from the body and their proboscis individually inserted in the capillary tube containing minimum essential media (MEM) to collect salivary expectorate. The resultant homogenates and the salivary expectorates were tested by plaque assay to determine virus infection, dissemination and transmission potential of the mosquitoes. RESULTS:A total of 515 female mosquitoes (311 Ae. bromeliae and 204 Ae. vittatus) were exposed to the East/Central/South Africa (ECSA) lineage of chikungunya virus. Aedes vittatus showed high susceptibility to the virus ranging between 75-90% and moderate dissemination and transmission rates ranging from 35-50%. Aedes bromeliae had moderate susceptibility ranging between 26-40% with moderate dissemination and transmission rates ranging from 27-55%. CONCLUSION:This study demonstrates that both Ae. vittatus and Ae. bromeliae populations from West Pokot and Kilifi counties in Kenya are competent vectors of chikungunya virus. Based on these results, the two areas are at risk of virus transmission in the event of an outbreak. This study underscores the need to institute vector competence studies for populations of potential vector species as a means of evaluating risk of transmission of the emerging and re-emerging arboviruses in diverse regions of Kenya

Changes in Host Cytokine Patterns of TB Patients with Different Bacterial Loads Detected Using 16S rRNA Analysis.

Tuberculosis (TB) has overtaken HIV as the biggest infectious disease killer, with the majority of deaths occurring in sub-Saharan Africa. However it is unknown how differences in bacterial load alter host immune profiles in the sputum and blood of TB patients.16S ribosomal RNA analysis was used to determine bacterial load in sputum samples obtained from 173 patients with active TB (57 pre-treatment and 116 post-treatment). Host analyte concentrations in sputum and Mycobacterium tuberculosis (Mtb) antigen stimulated whole blood assay supernatants were analysed using multiplex cytokine arrays.Multiple logistic regression adjusting for age, sex and HIV status showed highly significant correlation of bacterial load with IL1β, IL2, IL1RA, IL4, IL6, IL8, IL9, IL15, IL17, EOTAX, FGF, IFN-γ, GCSF, MCP1, M1P1α, M1P1β, PDGF, TNFα, VEGF in sputum. With increasing time on treatment, FGF levels in sputum displayed the most significant inverse correlation with reduction in bacterial load.We show that differences in bacterial load correlates with changes in several host biomarkers. These findings have implications for development of tests for TB diagnosis and treatment response

High risk for human exposure to Rift Valley fever virus in communities living along livestock movement routes : A cross-sectional survey in Kenya

Introduction: Multiple outbreaks of Rift Valley Fever (RVF) with devastating effects have occurred in East Africa. These outbreaks cause disease in both livestock and humans and affect poor households most severely. Communities living in areas practicing nomadic livestock movement may be at higher risk of infection. This study sought to i) determine the human exposure to Rift Valley fever virus (RVFV) in populations living within nomadic animal movement routes in Kenya; and ii) identify risk factors for RVFV infection in these communities. Methods: A cross-sectional descriptive study design was used. Samples were collected from the year 2014 to 2015 in a community-based sampling exercise involving healthy individuals aged ≥18 years from Isiolo, Tana River, and Garissa counties. In total, 1210 samples were screened by ELISA for the presence of immunoglobulin IgM and IgG antibodies against RVFV. Positive results were confirmed by plaque reduction neutralization test. Results: Overall, IgM and IgG prevalence for all sites combined was 1.4% (95% CI 0.8–2.3%) and 36.4% (95% CI 33.8–39.2%), respectively. Isiolo County recorded a non-significant higher IgG prevalence of 38.8% than Garissa 35.9% and Tana River 32.2% (Chi square = 2.5, df = 2, p = 0.287). Males were significantly at higher risk of infection by RVFV than females (OR = 1.67, 95% CI 1.17–2.39, p<0.005). Age was significantly associated with RVFV infection (Wald Chi = 94.2, df = 5, p<0.0001). Individuals who had regular contact with cattle (OR = 1.38, 95%CI 1.01–1.89) and donkeys (OR = 1.38, 95%CI 1.14–1.67), or contact with animals through birthing (OR = 1.69, 95%CI 1.14–2.51) were significantly at a greater risk of RVFV infection than those who did not. Conclusion: This study demonstrated that although the Isiolo County has been classified as being at medium risk for RVF, virus infection appeared to be as prevalent in humans as in Tana River and Garissa, which have been classified as being at high risk. Populations in these counties live within nomadic livestock movement routes and therefore at risk of being exposed to the RVFV. Interventions to control RVFV infections therefore, should target communities living along livestock movement pathways