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Rift Valley fever (RVF) is a mosquito-borne viral zoonotic disease that causes significant economic and public health impacts in Kenya. Currently, there is inadequate information on rainfall patterns and mosquito diversity, including the dominant species in Nyandarua. Therefore, this study aimed to determine the rainfall patterns, relative abundance, and diversity of mosquito species that can transmit the RVF virus (RVFV) in Nyandarua. Mosquitoes were purposively collected from all the homesteads with suspect RVF cases in 10 villages using the CDC light trap during the dry (January 2021), long (July 2020), and short (November 2021) rainy seasons. Rainfall data was derived from the Climate-SERV satellite database. The mosquitoes were identified morphologically using a dissecting microscope and their identities, as well as genetic diversity, were determined using sequencing and phylogenetic analysis of the CO1 gene. A total of 97, 328, and 366 mosquitoes were trapped during the dry, long and short rainy seasons, respectively. There was variation in the average daily rainfall between 2015 and 2021 during the three seasons. Of the mosquitoes trapped, 71 (9%) were males while 720 (91%) were females with 26 (4%) mosquitoes being blood-fed. During the three seasons, various species of mosquitoes including Culex pipiens (58%), Culex theileri (16%), Culex vansomereni (3%), Culex rima (2%), and Culex perexiguus (3%) were identified (Simpson index = 0.4). Culex pipiens was the most dominant species in this ecosystem (Shannon index = 1.2). We conclude that the anomalous variations in rainfall patterns may be correlated with the emergence of diverse species of mosquitoes that have the potential to transmit RVFV to animals in Nyandarua.

BACKGROUND Ruminant production plays a major role in the Kenyan livestock sector, but they face a myriad of disease threats including zoonoses. The objective of this study was to map the ruminant livestock value chains and describe disease risks and their implication to pastoral livelihoods in Kajiado South sub-county, Kenya. This area is characterised by a highly intertwined wildlife-livestock-human interface which is ideal for transmission of zoonoses and other livestock diseases to connected systems and farms. METHODS The study used a cross-sectional design, where primary sampling units were people including pastoralists who operated in critical livestock value chain nodes including slaughterhouses, slaughter slabs and livestock markets. Data were collected using focus group discussions (FGDs), semi-structured interviews (SSIs) and key informant interviews (KIIs) using published participatory methods including listing, probing and pairwise ranking. RESULTS A number of constraints to livestock production including diseases, poor extension services and drought were encountered in the study area. In the disease constraint, they treated their animals by themselves, whichlead to misuse of drugs thus to antibacterial resistance. The kind of diseases they may contract due to their livelihoods were mentioned among others, anthrax, brucellosis, Rift Valley Fever, tuberculosis, tapeworms and rabies, in that order. Foot and mouth disease (FMD) and lumpy skin disease (LSD) were mentioned across the FGDs that using the animal products, the pastoralists came down with similar flu symptoms. CONCLUSION From the pastoralists’ point of view the inputs in the value chains were self-medication of their animals leading a possible misuse of drugs without proper withdrawal periods; they were able to identify the disease risks including zonooses they were faced with. A better understanding of infection processes at the along the ruminant value chains is needed to minimise disease transmission, and it is this which this study aimed to improve.

Three months since the detection of the first COVID-19 case in Africa, almost all countries of the continent continued to report lower morbidity and mortality than the global trend, including Europe and North America. We reviewed the merits of various hypotheses advanced to explain this phenomenon, including low seeding rate, effective mitigation measures, population that is more youthful, favorable weather, and possible prior exposure to a cross-reactive virus. Having a youthful population and favorable weather appears compelling, particularly their combined effect; however, progression of the pandemic in the region and globally may dispel these in the coming months.

The World Health Organization (WHO) declared COVID-19 a pandemic on March 11, 2020 and by November 14, 2020 there were 53.3M confirmed cases and 1.3M reported deaths in the world. In the same period, Ethiopia reported 102K cases and 1.5K deaths. Effective public health preparedness and response to COVID-19 requires timely projections of the time and size of the peak of the outbreak. Currently, Ethiopia under the COVAX facility has begun vaccinating high risk populations but due to vaccine supply shortages and the absence of an effective treatment, the implementation of NPIs (non-pharmaceutical interventions), like hand washing, wearing face coverings or social distancing, still remain the most effective methods of controlling the pandemic as recommended by WHO. This study proposes a modified Susceptible Exposed Infected and Recovered (SEIR) model to predict the number of COVID-19 cases at different stages of the disease under the implementation of NPIs at different adherence levels in both urban and rural settings of Ethiopia. To estimate the number of cases and their peak time, 30 different scenarios were simulated. The results indicated that the peak time of the pandemic is different in urban and rural populations of Ethiopia. In the urban population, under moderate implementation of three NPIs the pandemic will be expected to reach its peak in December, 2020 with 147,972 cases, of which 18,100 are symptomatic and 957 will require admission to an Intensive Care Unit (ICU). Among the implemented NPIs, increasing the coverage of wearing masks by 10% could reduce the number of new cases on average by one-fifth in urban-populations. Varying the coverage of wearing masks in rural populations minimally reduces the number of cases. In conclusion, the models indicate that the projected number of hospital cases during the peak time is higher than the Ethiopian health system capacity. To contain symptomatic and ICU cases within the health system capacity, the government should pay attention to the strict implementation of the existing NPIs or impose additional public health measures.

Background One Health is particularly relevant to the Horn of Africa where many people’s livelihoods are highly dependent on livestock and their shared environment. In this context, zoonoses may have a dramatic impact on both human and animal health, but also on country economies. This scoping review aimed to characterise and evaluate the nature of zoonotic disease research in the Horn region. Specifically, it addressed the following questions: (i) what specific zoonotic diseases have been prioritised for research, (ii) what data have been reported (human, animal or environment), (iii) what methods have been applied, and (iv) who has been doing the research? Methodology/principal findings We used keyword combinations to search online databases for peer-reviewed papers and theses. Screening and data extraction (disease, country, domain and method) was performed using DistillerSR. A total of 2055 studies focusing on seven countries and over 60 zoonoses were included. Brucellosis attracted the highest attention in terms of research while anthrax, Q fever and leptospirosis have been comparatively under-studied. Research efforts did not always align with zoonoses priorities identified at national levels. Despite zoonoses being a clear target for ‘One Health’ research, a very limited proportion of studies report data on the three domains of human, animal and environment. Descriptive and observational epidemiological studies were dominant and only a low proportion of publications were multidisciplinary. Finally, we found that a minority of international collaborations were between Global South countries with a high proportion of authors having affiliations from outside the Horn of Africa. Conclusions/significance There is a growing interest in zoonoses research in the Horn of Africa. Recommendations arising from this scoping review include: (i) ensuring zoonoses research aligns with national and global research agendas; (ii) encouraging researchers to adopt a holistic, transdisciplinary One Health approach following high quality reporting standards (COHERE, PRISMA, etc.); and (iii) empowering local researchers supported by regional and international partnerships to engage in zoonoses research., Author summary Zoonoses are diseases that are transmissible between animals and humans. Some emerging or re-emerging zoonoses, like avian influenza, regularly make the headlines in international media. Others, like rabies or echinococcosis, which mainly affect poor communities, attract much less attention, and are considered neglected by the World Health Organisation (WHO). In the Horn of Africa, many people live in close proximity to livestock and depend on them for food and income. Their frequent interaction with animals increases the risk of contracting zoonoses. In our work, we have searched for existing research publications on zoonoses in the Horn of Africa to guide future research on most neglected areas. Based on 2055 publications, we have described which zoonoses have been studied where and using which method. Notably, we found that very limited research followed One Health approaches. That implies that separate focus was given to animals or humans and a single method or discipline was used, while the One Health approach advocates for multidisciplinary and multisectoral collaboration to address complex issues like zoonoses. Finally, we identified that a majority of authors were affiliated with countries from the Global North which hinders relevance, equity and sustainability of Global North-Global South research collaborations.

INTRODUCTION: Brucellosis is among the world’s most widespread zoonotic diseases which is recognized as a public health concern in both developed and developing countries. It is endemic in Kenya’s pastoral communities where it is associated with significant economic losses due to decreased animal productivity and high burden in humans. The objectives of this study were: i) To estimate the sero-prevalence and determine the risk factors of brucellosis in humans ii) To assess the knowledge attitude and practices (KAP) of a pastoral community in relation to brucellosis transmission and control.

The World Health Organisation (WHO) declared COVID-19 a pandemic on March 11, 2020 and by November 14, 2020 there were 53.3M confirmed cases and 1.3M reported deaths in the world. In the same period, Ethiopia reported 102K cases and 1.5K deaths. Effective public health preparedness and response to COVID-19 requires timely projections of the time and size of the peak of the outbreak. Currently, in the absence of vaccine or effective treatment, the implementation of NPIs (non-pharmaceutical interventions), like hand washing, wearing face coverings or social distancing, is recommended by WHO to bring the pandemic under control. This study proposes a modified Susceptible Exposed Infected and Recovered (SEIR) model to predict the number of COVID-19 cases at different stages of the disease under the implementation of NPIs with different adherence levels in both urban and rural settings of Ethiopia. To estimate the number of cases and their peak time, 30 different scenarios were simulated. The results reveal that the peak time of the pandemic is different in urban and rural populations of Ethiopia. In the urban population, under moderate implementation of three NPIs the pandemic will be expected to reach its peak in December, 2020 with 147,972 cases, of which 18,100 are symptomatic and 957 will require admission to an Intensive Care Unit (ICU). Among the implemented NPIs, increasing the coverage of wearing masks by 10% could reduce the number of new cases on average by one-fifth in urban-populations. Varying the coverage of wearing masks in rural populations minimally reduces the number of cases. In conclusion, the projection result reveals that the projected number of hospital cases is higher than the Ethiopian health system capacity during the peak time. To contain symptomatic and ICU cases within health system capacity, the government should give attention to the strict implementation of the existing NPIs or impose additional public health measures.

Background Malaria causes the greatest public health burden in sub-Saharan Africa where high mortality occurs mainly in children under 5 years of age. Traditionally, malaria has been reported mainly in the lowlands endemic regions of western Kenya, while the highlands of the Rift Valley have been relatively free except for the sporadic epidemics in some areas. Baringo County is located in the Kenyan highlands. The county generally experiences seasonal transmission of malaria. A few hotspots which experience continuous malaria transmission in the county do however exist. The objective of this study was to assess malaria infection status and identify areas with continuous transmissions with a view to mapping out probable transmission hot spots useful in mounting focused interventions within the county. Methods Systematic sampling was employed to identify 1668 primary school pupils from fifteen primary schools located in 4 ecological zones (lowland, midland, highland and riverine) of three sub-counties of Baringo. Finger prick blood sampling was done every 4 months (during the dry season in February/March, after the long rains in June/July and short rains in November 2015). Malaria occurrence was tested using rapid diagnostic test kit (CareStart HRP-2 Pf). Microscopic examination was done on all RDT positive and 10% of negative cases. Results A total of 268 (16.1%), out of 1668 pupils tested positive for Plasmodium falciparum by RDT; 78% had a single episode, 16.8% had 2 episodes, 4.9% had 3 episodes and 0.4% had 4 episodes. The riverine zone had the highest malaria cases (23.2%) followed by lowlands (0.9%). No malaria cases were detected in the midland zone while highland zone recorded only few cases during the third follow up. Up to 10.7% of malaria cases were reported in the dry season, 2.9% during the long rains and 5.7% in short rains season. Conclusions Malaria infection was prevalent in Baringo County and was mainly restricted to the riverine zone where transmission is continuous throughout the year. High malaria prevalence occurred in the dry season compared to the wet season. Even though malaria transmission is relatively low compared to endemic regions of Kenya, there is a need for continued monitoring of transmission dynamics under changing climatic conditions as well as establishing expanded malaria control strategies especially within the riverine zone which would include an integrated mosquito control and chemotherapy for infected individuals.

Rift Valley fever (RVF) is a vector-borne zoonotic disease caused by phlebovirus in the family Bunyaviridae. In Kenya, major outbreaks occurred in 1997-1998 and 2006-2007 leading to human deaths, huge economic losses because of livestock morbidity, mortality, and restrictions on livestock trade.This study was conducted to determine RVF seroprevalence in cattle, sheep, and goats during an interepidemic period in Garissa County in Kenya.In July 2013, we performed a cross-sectional survey and sampled 370 ruminants from eight RVF-prone areas of Garissa County. Rift Valley fever virus (RVFV) antibodies were detected using a multispecies competitive enzyme-linked immunosorbent assay. Mixed effect logistic regression models were used to determine the association between RVF seropositivity and species, sex, age, and location of the animals.A total of 271 goats, 87 sheep, and 12 cattle were sampled and the overall immunoglobulin G seroprevalence was 27.6% (95% CI [23-32.1]). Sheep, cattle, and goats had seroprevalences of 32.2% (95% CI [20.6-31]), 33.3% (95% CI [6.7-60]), and 25.8% (95% CI [22.4-42]), respectively. Seropositivity in males was 31.8% (95% CI [22.2-31.8]), whereas that of females was 27% (95% CI [18.1-45.6]).The high seroprevalence suggests RVFV circulation in domestic ruminants in Garissa and may be indicative of a subclinal infection. These findings provide evidence of RVF disease status that will assist decision-makers to flag areas of high risk of RVF outbreaks and prioritize the implementation of timely and cost-effective vaccination programs.

Summary To improve estimates of C. burnetii epidemiology in Kenya, a survey was undertaken in small ruminants in Baringo County, where acute cases of Q fever in humans had been reported in 2014. From 140 household herds selected, 508 (60.5%) goats and 332 (39.5%) sheep were included and an indirect ELISA assay for C. burnetii IgG antibodies performed. In addition, epidemiological information at both herd and animal level was collected. Generalized mixed-effects multivariable logistic model using herd as the random effect was used to determine variables correlated to the outcome. Overall seroprevalence was 20.5% (95% CI: 17.8%, 23.3%). Goats had 26.0% (95% CI: 22.2%, 30.0%) compared to sheep 12.2% (95% CI: 8.7%, 16.0%). Nomadic pastoralism, goats and older animals (>1 year) were associated with greater risk of C. burnetii seropositivity (P = ≤0.05). Heterogeneity in C. burnetii seropositivity was observed across the sublocations (P = 0.028). Evidence of C. burnetii exposure in small ruminants revealed poses a potential risk of exposure to the people living in close proximity to the animals. We recommended integrated animal–human surveillance and socio-economic studies for C. burnetii, to aid our understanding of the risk of transmission between the animals and humans, and in the design of prevention and control strategies for the disease in the region.

Background: Rabies causes an estimated 59,000 human deaths annually. In Kenya, rabies was first reported in a dog in 1912, with the first human case reported in 1928. Here we examine retrospective rabies data in Kenya for the period 1912 – 2017 and describe the spatial and temporal patterns of rabies occurrence in the country. Additionally, we detail Kenya’s strategy for the elimination of dog-mediated human rabies by 2030. Methods: Data on submitted samples and confirmed cases in humans, domestic animals and wildlife were obtained from Kenya’s Directorate of Veterinary Services. These data were associated with the geographical regions where the samples originated, and temporal and spatial trends examined. Results: Between 1912 and the mid 1970’s, rabies spread across Kenya gradually, with fewer than 50 cases reported per year and less than half of the 47 counties affected. Following an outbreak in the mid 1970’s, rabies spread rapidly to more than 85% of counties, with a 4 fold increase in the percent positivity of samples submitted and number of confirmed rabies cases. Since 1958, 7,584 samples from domestic animals (93%), wildlife (5%), and humans (2%) were tested. Over two-thirds of all rabies cases came from six counties, all in close proximity to veterinary diagnostic laboratories, highlighting a limitation of passive surveillance. Conclusions: Compulsory annual dog vaccinations between 1950’s and the early 1970’s slowed rabies spread. The rapid spread with peak rabies cases in the 1980’s coincided with implementation of structural adjustment programs privatizing the veterinary sector leading to breakdown of rabies control programs. To eliminate human deaths from rabies by 2030, Kenya is implementing a 15-year step-wise strategy based on three pillars: a) mass dog vaccination, b) provision of post-exposure prophylaxis and public awareness and c) improved surveillance for rabies in dogs and humans with prompt responses to rabies outbreaks.

IntroductionZoonotic diseases have varying public health burden and socio-economic impact across time and geographical settings making their prioritization for prevention and control important at the national level. We conducted systematic prioritization of zoonotic diseases and developed a ranked list of these diseases that would guide allocation of resources to enhance their surveillance, prevention, and control.MethodsA group of 36 medical, veterinary, and wildlife experts in zoonoses from government, research institutions and universities in Kenya prioritized 36 diseases using a semi-quantitative One Health Zoonotic Disease Prioritization tool developed by Centers for Disease Control and Prevention with slight adaptations. The tool comprises five steps: listing of zoonotic diseases to be prioritized, development of ranking criteria, weighting criteria by pairwise comparison through analytical hierarchical process, scoring each zoonotic disease based on the criteria, and aggregation of scores.ResultsIn order of importance, the participants identified severity of illness in humans, epidemic/pandemic potential in humans, socio-economic burden, prevalence/incidence and availability of interventions (weighted scores assigned to each criteria were 0.23, 0.22, 0.21, 0.17 and 0.17 respectively), as the criteria to define the relative importance of the diseases. The top five priority diseases in descending order of ranking were anthrax, trypanosomiasis, rabies, brucellosis and Rift Valley fever.ConclusionAlthough less prominently mentioned, neglected zoonotic diseases ranked highly compared to those with epidemic potential suggesting these endemic diseases cause substantial public health burden. The list of priority zoonotic disease is crucial for the targeted allocation of resources and informing disease prevention and control programs for zoonoses in Kenya.

Eleven medicinal plants used by traditional healers in Machakos and Kitui District were screened, namely: Ajuga remota Benth, Aloe secundiflora Engl, Amaranthus hybridus L, Cassia didymobotrya Fes, Croton macrostachyus Del, Entada leptostachya Harms, Erythrina abyssinica DC, Harrisonia abyssinica Oliv, Schkuhria pinnata O. Ktze, Terminalia kilimandscharica Engl and Ziziphus abyssinica Hochst for potential antibacterial activity against four medically important bacterial strains, namely: Bacillus cereus ATCC 11778, Escherichia coli ATCC 25922, Micrococcus lutea ATCC 9341 and Pseudomonas aeruginosa ATCC 27853. The antibacterial activity of methanol extracts was determined as the minimum inhibitory concentration (MIC). The plant extracts were more active against Gram-positive (G+) than Gram-negative (G-) bacteria. The positive controls were streptomycin and benzylpenicillin for G- and G+ bacteria, respectively, both had a significant MIC at

Background: Rift Valley Fever (RVF) is a mosquito-borne viral zoonosis that was first isolated and characterized in 1931 in Kenya. RVF outbreaks have resulted in significant losses through human illness and deaths, high livestock abortions and deaths. This report provides an overview on epidemiology of RVF including ecology, molecular diversity spatiotemporal analysis, and predictive risk modeling.Methodology: Using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched for relevant RVF publications in repositories of the World Health Organization Library and Information Networks for Knowledge (WHOLIS), U.S Centers for Disease Control and Prevention (CDC), and Food and Agricultural Organization (FAO). Detailed searches were performed in Google Scholar, SpringerLink, and PubMed databases and included conference proceedings and books published from 1931 up to 31st January 2015.Results and discussion: A total of 84 studies were included in this review; majority (50%) reported on common human and animal risk factors that included consumption of animal products, contact with infected animals and residing in low altitude areas associated with favorable climatic and ecological conditions for vector emergence. A total of 14 (16%) of the publications described RVF progressive spatial and temporal distribution and the use of risk modeling for timely prediction of imminent outbreaks. Using distribution maps, we illustrated the gradual spread and geographical extent of disease; we also estimated the disease burden using aggregate human mortalities and cumulative outbreak periods for endemic regions.Conclusion: This review outlines common risk factors for RVF infections over wider geographical areas; it also emphasizes the role of spatial models in predicting RVF enzootics. It, therefore, explains RVF epidemiological status that may be used for design of targeted surveillance and control programs in endemic countries.Keywords: Rift Valley Fever; spatiotemporal; modeling; epidemiology(Published: 31 July 2015)Citation: Infection Ecology and Epidemiology 2015, 5: 28024 - http://dx.doi.org/10.3402/iee.v5.28024

Seven medicinal plant extracts traditionally used in Kenya, mainly for management of infectious conditions, were chosen and screened for their antibacterial activity against Gram-negative (Pseudomonas aeruginosa and Escherichia coli) and Gram-positive (Bacillus cereus and Staphylococcus aureus) bacteria. Antibacterial activity was tested using the broth dilution method. Harrisonia abyssinica and Terminalia kilimandscharica extracts showed significant activity against Gram+ and Gram- bacteria. The methanolic extracts of T. kilimandscharica bark and H. abyssinica bark and leaves showed minimum inhibitory activity against all tested bacteria, with minimal inhibitory concentrations ranging from 25-150 mg/mL. Ajuga remota and Amaranthus hybridus, which are lethal to brine shrimp nauplii, showed significantly lower antibacterial activity than those that were relatively non-toxic.

Background Ethnobotanical pharmacopoeia is confidently used in disease intervention and there is need for documentation and preservation of traditional medical knowledge to bolster the discovery of novel drugs. The objective of the present study was to document the indigenous medicinal plant utilization, management and their extinction threats in Samburu District, Kenya. Methods Field research was conducted in six divisions of Samburu District in Kenya. We randomly sampled 100 consented interviewees stratified by age, gender, occupation and level of education. We collected plant use data through semi-structured questionnaires; transect walks, oral interviews and focus groups discussions. Voucher specimens of all cited botanic species were collected and deposited at University of Nairobi's botany herbarium. Results Data on plant use from the informants yielded 990 citations on 56 medicinal plant species, which are used to treat 54 different animal and human diseases including; malaria, digestive disorders, respiratory syndromes and ectoparasites. Conclusion The ethnomedicinal use of plant species was documented in the study area for treatment of both human and veterinary diseases. The local population has high ethnobotanical knowledge and has adopted sound management conservation practices. The major threatening factors reported were anthropogenic and natural. Ethnomedical documentation and sustainable plant utilization can support drug discovery efforts in developing countries.