PHD-Department of Zoologial Sciences

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    Cancer Epidemiology, Transforming Growth Factor-Beta Levels and Associated Infections in Meru and Tharaka Nithi Counties, Kenya
    (Kenyatta University, 2022) Muthoni, Gitonga Ciriaka; Michael Gicheru; Joshua Mutiso
    Cancer is one of the leading causes of morbidity and mortality worldwide with approximately 14 million cases annually. In Kenya, cancer as a disease ranks third as a cause of death after infectious and cardiovascular diseases. In Meru County, cancer cases have reached alarming levels. Out of all cases referred to Kenyatta National Hospital in Nairobi for cancer therapy in 2016, fifteen percent were from Meru County. Factors contributing to high cancer incidences in Meru County are not well documented. In addition, the true prevalence of cancer in this County is not known, therefore, much emphasizes of putting proper infrastructural facilities and human capacity development is not in place to combat cancer. The current study was aimed at determining the prevalence, distribution, risk factors and infections associated with cancer in Meru and Tharaka Nithi Counties. The study also aimed at determining the levels of transforming growth factor-beta levels in breast cancer patients with an aim of exploring application of these data in breast cancer diagnosis and management. A random selection of patients aged between 5 to 82 years clinically diagnosed as cancer patients who were visiting Meru and Chuka General Hospitals for a period of one year were recruited for the study. A total of 196 cancer patients were recruited for the study. The participants were requested to give a verbal consent and respond to a brief questionnaire concerning their age, type of cancer they were suffering from, exposure to predisposing factors, chronic coinfection, family history of cancer among other factors. Blood samples were collected to test for immunosuppressive cytokine and infectious diseases. Stool samples were collected and analysed by microscopy to detect for gastrointestinal parasitic infestation. Data was analyzed using statistical package for social sciences (SPSS). Statistical analysis involved descriptive statistics such as frequencies, standard deviations and means of various risk factors. Analysis of variance (ANOVA) was used to analyse the differences among means of transforming growth factor-beta levels at different cancer stages. Chi square was used to compare categorical data. A P value ≤ 0.05 was considered statistically significant. The current study established that the prevalence of cancer in people visiting hospitals in Meru and Tharaka Nithi Counties was 32% and 38% respectively. Further, the study found that the prevalence trends of cancer cases in the two counties have been increasing over the last eight years (2011-2018). People above 50 years of age are the most prone to cancer followed by people in the age bracket of between 31 and 50 years. The risk factors for cancer included age, diet, unregulated use of agrochemicals, tobacco use, use of Khat, public water supply, environmental pollutants like smoke and contraceptive use. Elevated levels of transforming growth factor-beta were found in breast cancer patients when compared with healthy individuals. The most common diseases in cancer patients before cancer diagnosis included HIV/AIDS, pneumonia, tuberculosis, Human papillomavirus, diabetes, H. pylori infection and malaria. The study concludes that cancer is prevalent in Meru and Tharaka Nithi counties and the increases are associated with exposure to risk factors. It is therefore recommended that proper infrastructural and human capacity development be put in place to combat cancer. It is recommended that transforming growth factor-beta be evaluated further for its potential application in cancer diagnosis and staging.
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    Spatial-Temporal Changes of Mosquitoes Dynamics and Risks of Arboviruses to Livestock during a Period of Extreme Flooding of Lake Baringo, Kenya
    (Kenyatta University, 2021) Kamau, Samuel Kabochi; Michael Gicheru; Benson M. Mwangi; George N. Michuki
    The ecology of mosquitoes and associated arboviruses are heavily influenced by precipitation and retention of water in the environment. In 2011 to 2014, unprecedented flooding occurred in Lake Baringo flooding expansive area and inundated over 88km2 of the shoreline. The impact of this on animal health, livelihoods and ecology generated a lot of interest among stakeholders. The current study was aimed at assessing the spatial-temporal changes of mosquito abundance, diversity and associated risks to arboviruses in order to enrich control strategies for mosquitoes and zoonoses. This was a longitudinal study carried out for one year from October 2012 to October 2013. It analysed mosquito ecology, identified mosquitoes to species level where possible, characterized arboviruses and determined disease prevalence from livestock. Mosquitoes were trapped using Centre for Disease Control (CDC) light traps in three ecological zones namely swamp marshy habitat, flooded lake shoreline and dry rangeland. Blood was drawn from livestock to determine presence of arboviruses. A total of 386,624 individual mosquitoes were captured. The Anopheline mosquitoes constituted genus Anopheles, while the Culicinae constituted 10 genera namely Aedes, Culex, Mansonia, Hodgesia, Uranotaenia, Coquillettidia, Aedeomyia, Ficalbia, Theobaldia and Orthodomyia. Mosquitoes of genus Mansonia were the dominant species in the basin and accounted for 84.9% with 97.8% coming from flooded lake shoreline habitat. Genus Aedes formed 0.1% of total mosquito catches from the basin with 96.9% of the individuals caught coming from swamp marshy habitat. Isolated viruses were Culex flavivirus in mosquitoes, Aedes flavivirus and Rift Valley Fever virus in livestock blood. This study reports for the first time detection of nucleic acid for Aedes flavivirus, an insect specific flavivirus, from livestock blood even though it does not replicate in vertebrate cells. Of eight (8) sequences of isolated virus for Rift Valley Fever (RVF), only three (3) sequences were 100% similar and the other five (5) exhibited alterations at various nucleotide base positions. Results from Next Generation Sequencing produced nucleotide sequences identical to Aedes albopictus mosquito species for the first time in the area. The mean catches of mosquitoes between the three habitats from Lake Baringo basin was significantly different at (F (2, 27) =3.54; P=0.04). Also significantly different were mean catches of mosquitoes at night from communal grazing areas and homestead at (F (11, 12) =2.87; P=0.04). The flooded lake shoreline had the lowest diversity of Simpson’s Index at 0.13 due to dominance by mosquitoes of genus Mansonia. The swamp marshy and dry rangeland areas were more diverse in mosquito genera with Simpson’s Indices of 0.56 and 0.57 respectively. Overall infection prevalence in livestock with RVF virus was 10.4% with the highest risk encountered from swamp marshy habitat (7.8%), flooded shoreline (2.6%) and lowest at dry rangeland (0%). The risk of infection with arboviruses was significantly lower in the dry rangeland habitat than in flooded shoreline at (t (6) = 1.94; P=0.024). The findings indicate that unprecedented flooding altered the environmental tolerance range of different mosquito species and ecology and this affected the spatial-temporal parameters impacting on mosquitos’ composition, abundance and diversity in the expansive lake shoreline habitat. This increased the risks of transmission and infection with mosquito-borne arboviruses to livestock. It is recommended that both the relevant departments and agencies for livestock and human health develop a strategic approach for the control and mitigation against RVFV in wetlands and floods prone areas.
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    Some Aspects of the Ecology, Behaviour and Vectorial Capacity of the Tsetse Fly Glossina Austeni Newstead.
    (Kenyatta University, 1992) Owaga, Mary Ludvine Akoth
    A study was undertaken in the south coast of Kenya, on the tsetse fly species, Glossina austeni Newstead. The objective was to investigate its population ecology, behaviour and vectorial capacity. The main aspects studied were: habitat requirements and density, responses to sampling devices and methods, such as traps and odours, activity pattern, and infection with trypanosome parasites. Some aspects of the study, such as sampling and activity experiments, evaluation of density, dispersal and habitat requirements, and trypanosome infection rates, were conducted in the field. Others, such as assessment of the effect of temperature and relative humidity on activity and response to odours, and evaluation of the efficiency ofG. austeni in picking up trypanosome parasites from infective blood meals, and in transmitting them to the next mammalian host, were conducted in the laboratory. I' Sampling was carried out using five trap-types, the biconical, the NG2B, the Lancia (original), Lancia (modified) and the 4t traps, to determine whether G. austeni could be trapped in sufficient numbers, and which trap might be most suitable for routine sampling. Similarly, five odour sources were tested as baits: buffalo urine, cow urine, acetone, urine derived phenols and dry ice. Period of activity, and activity pattern as related to feeding, were determined by continuous trapping, using traps and stationary vehicle, and by laboratory observation in a flight chamber, where only olfactory, but no visual stimulant, was presented to the flies. To study the density and dispersal ofG. austeni, the method of markrelease- recapture was used. By this method a sample of tsetse flies.....
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    The Impact of Climatic Variability and Malaria Control Interventions on Malaria Parasite Prevalence and Vector Abundance in Western Kenya
    (Kenyatta University, 2020-11) Ototo, Ednah Nyagechanga
    The World Health Organization estimated annual global malaria mortality to be at 405,000 deaths in 2018 making malaria one of the most important diseases in the world. In Kenya, malaria control measures have been put up, however, the ongoing climate change and climatic variability is proving to be a great challenge. The aim of this study was to investigate the impact of climatic variability and malaria control interventions on malaria parasite prevalence and vector abundance in western Kenya. This was a longitudinal study where the same population was studied over a continuous period of time. Six sites; Iguhu, Emakakha, Marani, Kombewa, Rae and Miwani were selected for the study. Indoor resting mosquitoes were collected monthly from 2012 to 2014. Outdoor mosquito collections were done using rotator traps every two hours between 6pm-8pm during the same time period. Human behaviour study was also conducted in the study sites to show when the study participants stayed outdoors. Polymerase chain reaction was done to confirm species and Enzyme linked immunosorbent assay was done to confirm sporozoite infectivity. Bed net ownership in the study sites was analysed. Malaria parasitological surveys were conducted in 100 randomly selected children aged between 6-15 years in 2002-2003 and 2012-2015 in Iguhu to determine parasite prevalence and densities of sexual and asexual stages. Age-dependence in parasite infections was compared between the pre and post intervention period. Climate and clinical data were analysed from Iguhu and Marani from 1980 to 2015. Data on vector abundance, various malaria control interventions and asymptomatic malaria cases was collected from the study sites. The effects of temperature and rainfall on malaria parasites and vectors was shown using Poisson regression analysis. The results revealed 58.2% Anopheles gambiae were collected and 41.8% Anopheles funestus. Fifty percent of the study population stayed indoors in the study sites between 08.00pm-06.00am. Bed net ownership in 2012 averaged 87%. Plasmodium falciparum parasite prevalence among children ≤ 15 years of age reduced from 43.5% in the pre intervention period to 11.5% in the post intervention period, a 73.7% reduction in the post intervention period. Parasite densities per ml of blood of P. falciparum between the pre and post intervention period increased by 71.2%. The geometric mean gametocytaemia in Iguhu was 106.4 parasites/μl, in the post intervention period. Prevalence and density of P. falciparum showed no age-dependency during post-intervention period. Maximum temperature and rainfall were highly associated with the density of An. gambiae (χ2=2.44, d.f = 1, P= 0.015). Malaria cases showed a positive significant relationship with a 4-month moving average of the total monthly rainfall despite control. In conclusion, insecticide treated bed net use led to early feeding of malaria vectors before dawn and before dusk. The use of both bed nets and Artemisinin combination therapy for a prolonged period of time reduced parasitological resistance and transmission blocking immunity. Increased rainfall and maximum and minimum temperature led to the increase in malaria transmission even in areas where interventions were in place. Sustained use of insecticide treated nets as a component of integrated vector management is recommended to reduce early feeding of mosquitoes and prevent malaria transmission in children. Continuous surveillance of Plasmodium parasite transmission is also recommended to identify new malaria hotspots due to climatic
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    Digestibility, Growth and Economic Performance of Nile Tilapia (Oreochromis Niloticus) Fed on a Mixture of Plant Protein Diets in Cages
    (Kenyatta University, 2020) Maundu, Anne Munanie
    Fish feed is one of the critical components in aquaculture production and accounts for over 60% of total operational costs with protein component being the most expensive ingredient. Traditionally, fishmeal (FM) has been the primary dietary animal protein source. However, with dwindling capture fisheries, FM has become increasingly scarce and expensive due to its demand from human consumers and livestock feed manufacturers. This in turn makes the cost of fish feeds expensive leading to low profit margins in farmed fish. Therefore, there is need to identify alternative, low cost, and nutritionally balanced sources of protein for the growth of the industry. Although plant-based protein sources are viable alternative in replacing FM, there have been no studies on mixture of plant proteins to establish their economic utility in fish farming. This study evaluated the effects of replacing freshwater shrimp (caridina nilotica) meal (FSM), with varying levels of soybean (Glycine max) meal (SBM), cottonseed (Gossypium spp) meal (CSM) and sunflower (Helianthus annuus) meal (SFM) on growth performance, digestibility, whole body composition and economic returns in diets of Nile tilapia (Oreochromis niloticus). Fingerlings averaging 25g in body weight were stocked in net cages installed in three 800m2 fertilized earthen ponds. Each pond had 15 cages evaluating five diets with three replicates for a culture period of six months. Three experimental set ups were designed to evaluate the efficiency of a combination of SBM with other plant protein sources in replacing FSM in fish diets. In trial 1, five isonitrogenous (30% CP) and isocaloric (3.5 kcal g-1) diets were formulated, substituting Fresh water shrimp meal with Soybean meal at rates of 0, 25, 50, 75 and 100%.Trial 2 similar diets as above were formulated replacing fresh water shrimp meal with a combination of SBM, CSM and SFM at rates 0, 25, 50, 75 and 100%. In Trial 3, similar diets as in experiment 2 were formulated replacing FM with a combination of CSM and SFM at rates 0, 25, 50, 75 and 100%. All fish were fed twice daily at 10% of their body weight. Data were expressed as means and standard error of the mean. Growth and proximate composition were analyzed using one-way ANOVA at p< 0.05, and differences among treatment means identified using Tukeys Multiple Range Test. Results from the study in trial 1, showed that fish fed on D0 had higher final weight (p<0.05) than those fed on D1, D2 and D3, while D4 had the lowest weight. In trial 2, fish fed on D1 showed growth performance that did not differ significantly from fish fed D0. However, highest FM replacement (100%), significantly (p<0.05) reduced growth performance. In trial 3, D0 and D1 had significantly (p<0.05) higher mean weights than the rest of the treatments. In the three trials, similar survival was observed among treatments, but digestibility of protein decreased significantly (p<0.05) with increasing inclusion levels of PPSM in the diets. In trial 1, the ash content of carcass decreased significantly with increased levels of SBM. In trial 2, fish accumulated increasing levels of ash and crude fat with increasing levels of PPSM. In trial 3, crude fat increased significantly across all dietary treatments while ash content decreased with increasing levels of PPSM. Diet D3 in trial 1 was more economically viable although it was not significantly different (p>0.05) from D1 and D2. In trial 2 and 3, D0 and D1 were not significantly different hence D1 was more viable because it was cheaper than D0. Based on these findings, the present study concludes that the use of either pure fishmeal or fishmeal containing a mixture of 25% of plant proteins diets leads to similar growth performance in O. niloticus, the fishmeal containing the mixture of 25% plant proteins remarkably reduces the production costs and achieves higher profits than when the pure fishmeal is used. The present study therefore, recommends that for desirable net returns plant proteins can be used in fish farming.
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    Characterization and Control of Pathogenic Parasites in Nile Tilapia (Oreochromis Niloticus Linnaeus 1758) in Fish-farming Systems in Bungoma County, Kenya
    (Kenyatta University, 2020) Makilla, Davies Mukwabi
    In Kenya, fish farming has been expanding in recent years, with Government support through financial and input subsidies to small scale farmers. The sub sector generates a variety of benefits such as food and nutrition and develops trade. However, the sub sector faces the challenges of fish diseases, given that the fish production facilities support high-density living conditions that are favorable for spread of parasitic diseases. Besides, when fish that is infected is consumed by humans, the humans may be infected, especially when eaten fresh. Infected fish lowers their market value and sunctions may also be imposed on fish exports. Knowledge of fish parasites in aquaculture systems as well as treatment options available would enlighten fish farmers on the specific actions to take in order to harvest quality fish. The study was cross sectional carried out in Bungoma County from August 2015 to Decemebr 2017. The main objective of the study was to characterize and evaluate control options of pathogenic parasites present in fish farming systems in Bungoma County. Bungoma County was chosen for this study because it is one of the Counties that has high potential for fish farming. The County hosts one out of the public fish farms and hatcheries at Chwele besides authenticated private fish hatcheries. He hatcheries are sources of fish fingerlings as well as training and demonstration centres for fish farmers. At every fish pond, six water quality parameters were assessed using a portable auto sampler. Farmed Nile tilapia was randomly sampled to determine the pathogenic parasites and bacteria present in various organs. Commercial fish feeds were also purchased from two fish feed millers in Bungoma County and assessed for parasite presence. Polymerase Chain Reaction (PCR) and genetic sequencing analysis were conducted in order to assess the genes responsible for antimicrobial resistance. The data was entered into Micro Soft Excel (Windows 10) spreadsheet and analysed by SPSS Software. It was found that there was significant difference only in temperature of the pond water sampled across the sub counties (F=15.5; df=5; p<0.001). Helminthes recovered were Pallisentis tetraodontis, Pallisentis spp., Acanthocephalus spp., Procamallanus spp. and Philometroides spp. from Nile tilapia and Cleidodiscus spp. from pond water. Bacteria that were isolated from Nile tilapia were Vibrio vulnificus, Vibrio parahaemolyticus, Aeromonas hydrophila, and Pseudomonas aeruginosa. In fish pond water, Aeromonas hydrophila was isolated while Streptococcus iniae was isolated from fish feeds. Besides, there was a significant difference in distribution of total viable aerobic colony counts in fish ponds water across the different sub counties (H=6;df 5; P< 0.041). Furthermore, it was found that there was significant difference in the distribution of Aeromonas hydrophila in fish ponds across the different sub counties (H=3;df;P< 0.016). The external parasites were eliminated by formalin (36% formaldehyde) at concentration of 25ppm for 1h and Hydrogen peroxide at 75ppm for 30 min. The bacterial isolates were found to be significantly different in responses to antimicrobial agents (OLR;df= 16; P<0.00). When the bacterial isolates were subjected to PCR, all five bacterial pathogens isolated from fish, pond water and fish feeds were found to contain blaTEM gene amplified at 424bp. The sequences blaTEM gene returned 100% identity with GenBank Accession number; BankIt2236899 Seq1a MN114035 to Seq 9b MN114052). This study found that the blaTEM gene was present in recovered Vibrio parahaemolyticus, Aeromonas hydrophila, Pseudomonas aeruginosa and Streptococcus iniae. It is recommended that Formalin and hydrogen peroxide as well as potassium permanganate should used to manage fish helminthes in the ponds
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    Prevalence, Molecular Characterization and Antibiotic Sensitivity of Listeria Monocytogenes Isolated from Foods of Animal Origin in Nairobi and its Environs, Kenya
    (Kenyatta University, 2020-09) Kabui, Kevin Kinyua
    Food borne infections are an important public health concern worldwide with most being caused by pathogens that are zoonotic in nature. Among the most common food borne infection is listeriosis, caused by Listeria monocytogenes, a bacterium that is widely distributed in nature and which has been isolated in a wide array of foods. It mainly affects immunocompromised individuals including pregnant women, neonates and the elderly. Currently, in Kenya, there is no published data on the presence of this organism in ready to eat foods. The aim of this study was therefore to determine the prevalence, serotypes, virulence factors, genetic relationship and antibiotic susceptibility of L. monocytogenes from ready to eat meat products and milk products in Nairobi and its environs. A total of 570 samples; 350 milk products and 220 meat products were collected from selected retail markets in the study area. Isolation and identification was done as per the Bacteriological Analytical Manual protocol, and out of the 570 samples, 49 (8.59%) tested positive for Listeria spp after amplification of a 370 bp region of the prs gene. Twenty-one (42.8%) of these isolates were from milk products namely; milk powder (4.76%), short life pasteurized milk (4.76%), long life pasteurized milk (14.29%) and pasteurized milk from dispensing machines (76.19%). The rest, 28/49 (57.2%) were isolated from meat products namely; ham (7.14%), brawn (46.43%), polony (28.57%), salami (3.57%) and ready to eat meat bites (14.29%). Speciation of the Listeria isolates was done through multiplex PCR and of the 49 isolates, 22 were confirmed as L. monocytogenes through the amplification of a 509 bp region of the Lmo1030 gene. Of these L. monocytogenes isolates, 77.27% were from milk products while 22.72% were from meat products. The highest prevalence, 68.18 % was from dispensed milk while the lowest, 4.54% was from short life milk, long life milk and ham. Of the other 27 Listeria spp isolates, two were identified as L. welshimeri by amplification of a 281 bp region of the scrA gene while three were identified as L. innocua by amplification of a 749 bp region of the Lin0464 gene. The rest of the isolates, (22/27) were unidentified Listeria spp. The overall prevalence of L. monocytogenes was 3.86% (22/570). Molecular serotyping of the 22 L. monocytogenes isolates showed that 95.45% of the isolates carried both the ORF 2110 and the ORF 2819 genes characteristic of serotypes 4b,4d and 4e. A majority of these isolates (68.18%) were from milk collected from dispensing machines, two isolates from polony and an isolate each (4.55%) from long life milk, short life milk, brawn and ham. The remaining isolate (4.55%) carried the ORF2819 gene only, characteristic of serotype 1/2b, 3b, 4b, 4d, 4e and 7 and was isolated from brawn. All the isolates possessed hlyA, inlA, inlC, iap and actA virulence genes. Almost all the isolates (21/22) had the inlJ gene while inlB was only detected in 10/22 (45.45%) of the isolates. All L. monocytogenes were resistant to penicillin, 9.09% resistant to erythromycin and 4.54% resistant to sulfamethoxazole trimethoprim. All isolates were susceptible to gentamycin, chloramphenicol and tetracycline. The study concluded that processed ready to eat meat and milk products available to consumers were contaminated with the virulent form of L. monocytogenes that is responsible for up to 95% of Listeriosis cases reported worldwide. It is recommended that strict regulation of the processing and storage conditions of ready to eat foods be done to ensure they reach consumers pathogen free
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    Diagnosis and Epidemiology of Zoonotic Nontuberculous Mycobacteria among Dromedary Camels and Household Members in Samburu County, Kenya
    (Kenyatta University, 2020-09) Asaava, Lucas Luvai Azaale
    Zoonotic nontuberculous Mycobacteria (NTM) cross infect a wide range of domestic animals, wildlife and man causing various diseases. Despite the public health implications associated with mycobacterial infection and the existing close interaction of pastoralists and camels, information on diagnosis and epidemiology of zoonotic NTM amongst camels and closely associated community members is scanty. The present study was a one-health approach study involving diagnosis and epidemiology of zoonotic NTM infection among dromedary camels and associated household members in Samburu East sub-county. The study was cross sectional covering camels slaughtered at county abattoirs as well as household members and camels. Abattoirs sampled included Isiolo and Athi-River camel abattoirs, where all sampled camels were confirmed to have come from Samburu east. Household camel sampling strategy involved stratification of the study area to Wamba and Waso rearing areas. Sampling at abattoirs was consecutive for camels identified to have TB-like lesions during meat inspection. People presumed to have TB from amongst the sampled households were requested to provide a sputum sample. Screening of lactating camels for Mycobacteria infection was done using single intradermal comparative tuberculin test (SICTT) in a consecutive sample of 612 lactating camels from 83 households. A consolidated milk sample from all four mammary quarters was collected from 238 tuberculin test reactive camels. Post mortem (PM) examination was conducted on 1600 camels originating from the study area. A semi-structured questionnaire was administered to collect data on risk factors from 83 respondents. All milk, sputum and tissue samples were analysed at Kenya Medical Research Institute (KEMRI)/Centre for Respiratory Disease Research (CRDR) enhanced BSL2 laboratory using mycobacteriology, molecular speciation using GenoType® Mycobacterium line probe assay (HAINLifescience), drug susceptibility testing, 16S rDNA sequencing and phylogenetic analysis. This study was conducted between April, 2017 and December, 2018. Results indicated that the proportion of M. bovis and M. avium reactors was estimated at 6.05% and 39.38% respectively. Out of 238 milk samples, 57 (23.95%) had culture positive acid fast bacilli (AFB). Out of 132 suspected lesions on PM, 27/1600 1.69% (binomial 95%, CI: 1.11%-2.45%) were AFB positive on culture. Of the 48 sputum samples, 7 were AFB culture positive. The NTMs were observed to occur widely in various samples analysed, including post mortem lesions: M. fortuitum 17/27 (62.96%), M. scrofulaceum 3/27 (11%), M. szulgai 2/27 (7.4%); camel milk samples: M. szulgai 20/57 (35.09%), M. monacense 5/57 (8.77%), M. litorale 4/57 (7.02%), M. fortuitum 3/57 (5.26%), M. lehmannii 3/57 (5.26%), M. elephantis 3/57 (5.26%), M. duvalii 3/57 (5.26%); and in Human sputum samples: M. fortuitum 1/48 (2.08%), M. szulgai 2/48 (4.16%), and M. litorale 1/48 (2.08%) among others. These findings demonstrate high levels of infection with NTM in both humans and camels. Camel post mortem analyses revealed bronchial, mediastinal lymph nodes and lung lobes were most affected tissues. Several NTMs of medical importance with varying level of commonly used TB drugs sensitivity. The pattern of resistance to first-line TB drugs was as follows: Isoniazid (100%), rifampicin (97.9%) and ethambutol (65.3%). All NTM species isolated were highly resistant to first-line TB drugs. Camel breed, age, production system, origin of new introductions, migration and herd size were identified as risk factors for infection in camels (p<0.05). Surveillance and notification systems for NTMs including specific immunological test for NTMs diagnoses are needed. The public health significance of NTM in camels and humans needs further unravelling.
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    Effects of Probiotics on Growth, Flesh Quality and Hematoimmunological Status of Cultured Nile Tilapia (Oreochromis Niloticus) In Kirinyaga County, Kenya
    (Kenyatta University, 2020-08) Opiyo, Mary Adhiambo
    Nile tilapia (Oreochromis niloticus) culture in Kenya is mainly conducted in low input ponds where supplementary feed is given alongside pond fertilization. Excess nutrients in the culture water in form of nitrogen (N) and phosphorus (P) may make the culture environment susceptible to invasion by disease-causing microorganisms. In the recent past, probiotics have received much attention as a new strategy in fish health management and have been documented to improve fish growth performance and immunity in fish cultured in recirculating systems. However, their effect in tilapia cultured in low input ponds is still relatively unknown. In this study, monosex O. niloticus fingerlings with a mean weight of 39.75 ± 0.05 g were randomly stocked at 50 fish m-3 in 1.25 m3 cages in low input earthen ponds. The fish were fed twice daily at 3% body weight on seven isonitrogenous (28% crude protein) diets supplemented with either Saccharomyces cerevisiae (1×1010 CFU g-1) or Bacillus subtilis (1×109 CFU g-1) at different levels as follows: No probiotic (Diet 0); S. cerevisiae at 2 g kg−1 (Diet 1), 4 g kg−1 (Diet 2) and 6 g kg−1 (Diet 3); and B. subtilis at 5 g kg−1 (Diet 4), 10 g kg−1 (Diet 5) and 15 g kg−1 (Diet 6) for a period of 7 months. The fish were sampled monthly for weight and length measurements. Hemato-immunological parameters were determined by blood sampling and hematological analysis for red blood cells, white blood cell and haemoglobin counts. Blood serum assay was conducted using commercial enzyme-linked immunosorbent assay (ELISA) kits to determine the serum protein, albumin, globulin levels and lysozyme activity. Microbiological samples were analyzed through sub-culturing to obtain pure cultures on nutrient media and enumerated through standard methods. Results of the trials indicated that the highest performance was achieved with Diet 2. The highest final weight (255.31 ± 3.19 g), Specific growth rates (SGR) (0.77±0.01% day-1) and feed conversion ratio (FCR) (1.61 ± 0.02) were recorded in fish fed Diet 2. This was followed by fish fed Diet 5. Results of growth performance analysis indicated that fish fed on probiotic-supplemented diets had significantly better growth, nutrient utilization and FCR than fish fed on the control diet (P < 0.05). Probiotic supplementation significantly affected the body composition of the fish (P < 0.05). Saccharomyces cerevisiae at 4 g kg-1 (Diet 2) led to significantly high protein (86.06%) (P < 0.05) while B. subtilis at 5 g kg-1 (Diet 4) led to significantly higher protein (89.40%) (P < 0.05). Crude lipid and ash content were significantly lower in the fish fed probioticsupplemented diets (P < 0.05) compared to the control. Results of hemato-immunological analysis indicated that haemoglobin (Hb), red blood cells (RBC), white blood cells (WBC), serum protein, albumin, globulin and lysozyme activity were higher in fish fed on probiotic-supplemented diets and lower in the control group (Diet 0). Probiotic significantly affected hemato-immunological parameters (P < 0.05). Fish fed on probioticsupplemented diets retained the probiotics in their guts and had lower microbial load in their muscle (P < 0.05). This study shows that incorporation of probiotics in diets of Nile tilapia in low input ponds promotes growth performance, enhances body composition, improves immunity and manipulates gut microbiota of fish. The two probiotics differ in effect at different levels of application. Probiotic S. cerevisiae exhibited the best performance at 4 g kg-1 while B. subtilis had the best performance at 10 g kg-1. Probiotics are therefore recommended for use in low input fish culture systems for better nutrient utilization, higher yields and improved fish health for increased aquaculture production.
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    Circulatory Cytokines and Hematological Profiles as Biomarkers of HIV and AIDS Progression
    (Kenyatta University, 2019) Mugwe, Jane Nyambura
    Cytokines are polypeptides that have a fundamental role in communication within the immune system and in allowing the immune system and host tissue cells to exchange information. They play a central role in the pathogenesis of many diseases including Acquired Immunodeficiency Deficiency Syndrome (AIDS). Cytokines reflect the local or systemic inflammatory milieu, and could serve as predictive biomarkers in Human Immunodeficiency Virus (HIV) infection. Hematological abnormalities are among the most common complications caused by HIV infection and seem to be dependent on the level of virus replication. The aim of this study was to identify circulatory cytokine biomarkers and hematological profiles measureable in blood that could predict the progression of HIV disease in the course of infection. This study was done at the Nakuru Provincial General Hospital (PGH). Eighty individuals were recruited for this study that comprised of forty individuals newly diagnosed with HIV-1 (treatment naïve), twenty HIV negative individuals and twenty HIV positive individuals that were on treatment with highly active antiretroviral therapy (HAART). Hematological parameters were analyzed using hematology auto analyzer system; cytokine types and concentrations were determined by flowcytometry using multiplex cytokine immunoassay and CD4 T cell counts were measured by flowcytometry using Becton and Dickinson Fluorescence Activated Cell Sorter (BD FACS) count. Statistical analysis were done using SPSS version 17. Descriptive statistics were applied; analyses of variance was used to determine the differences in mean circulatory cytokine levels, mean hematological profiles and mean CD4 T cell counts between the subgroups forming the study population. The associations between immunological and hematological profiles were determined. The study found significant differences in the mean Interleukin12p70 (p<0.001), Tumor Necrosis Factor (p<0.05), Interleukin 10 (p<0.05), Interleukin 6 (p<0.005) and Interleukin 1-β (p<0.05) between treatment naïve HIV patients, HIV patients on HAART and HIV negative patients. No significant differences were found between the mean White Blood Cell counts and Red Blood Cell counts (p>0.05) between the treatment naïve HIV patients, HIV negative patients and HIV patients on HAART but there were significant differences between the mean hematocrit (HCT) (p<0.05); hemoglobin (HGB) (p<0.05) and platelets (PLT) (p<0.05). This study also found significant differences in the mean volume of erythrocytes (MCV) (p<0.05), mean content of hemoglobin (MCH) (p<0.05), mean concentration of hemoglobin (MCHC) (p<0.05), mean platelet volume (MPV) (p<0.001), relative width of the distribution of platelets (PDW) (p<0.001) and the absolute content of the mixture of monocytes, basophils and eosinophils (Mid#) (p<0.05). Significant differences in the mean CD4 T cell counts (p<0.001) were observed between the treatments naïve HIV patients, HIV negative patients and HIV patients on HAART. The study found several identical associations between immunological and hematological profiles among the study groups. The study showed that early period of HIV infection is characterized by varying circulatory cytokine levels and could be useful biomarkers and indicators of early immune activation of HIV disease. The results from this study also show that acute HIV infection affects hematological profiles, involving all the blood parameters, some of which may act as indicators of HIV disease progression. The study recommends the use of low cost hematologic tests as biomarkers of disease progression in resource limited settings and also a holistic treatment of HIV infected patients that include supplements to monitor and improve blood parameters and indices in addition to antiretroviral therapy.
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    Residual Effects of Insecticide-Based Malaria Control Interventions on Malaria Vectors and the Status of Insecticide Resistance in Western Kenya
    (Kenyatta University, 2019-02) Wanjala, Christine Ludwin
    Malaria is a human disease caused by a sporozoan from the genus Plasmodium, transmitted by a bite of Anopheles mosquitoes. Insecticides remain the major tool for control of malaria vectors in Kenya and therefore the potential of such programs to be compromised by the reported insecticide resistance is a major concern. Studies in western Kenya have reported reemergence of morbidity and malaria attributed child mortality which has been linked to reported spread of insecticide resistance in anophiline mosquitoes. The aim of this study was to evaluate the residual effect of insecticides used for indoor residual spraying and impregnated on long lasting insecticide nets, and also determine the status of insecticide resistance in malaria vectors from western Kenya. Wall bioassays were performed on mud slabs and filter papers sprayed with lambdacyhalothrin and deltamethrin using mosquitoes collected from Ahero, Kisian, Chulaimbo, Emutete, Emakakha, Iguhu and Kabula. Net bioassays were performed on long lasting insecticide nets (LLINs) collected from the field using wild caught mosquitoes from Emutete and Kabula. Kisumu strain, a susceptible reference strain was used as a control. Chemical analysis of the netting material was performed using gas chromatography. World Health Organization tube bioassays was conducted using standard diagnostic dosages of Lambdacyhalothrin, Deltamethrin, Permethrin, DDT, Bendiocarb and Malathion tested on Anopheles mosquitoes collected from Ahero, Kisian, Chulaimbo, Emutete, Emakakha, Iguhu and Kabula. Biochemical assays, where the enzymatic activity of three enzymes (monooxygenases, esterases and Glutathione S-trasferases) were performed on susceptible and resistant mosquitoes preserved after WHO tube bioassays. Mosquitoes were identified to species level using Polymerase Chain Reaction. Genotyping was done on the susceptible and resistant mosquitoes after the WHO tube bioassays using Real-Time Polymerase Chain Reaction. Pyrethroid susceptible An. gambiae and An. arabiensis colonies from Bungoma and Ahero was raised and their genetic and biochemical changes monitored from generation to generation. The mortality of mosquitoes from all sites decreased significantly with time after spraying (75% mortality after six months) and with the age of the LLINs (60% mortality after 24 months). Insecticide concentration decreased significantly from 0.14 μg/ml in new LLINs to 0.077 μg/ml in LLINs older than 18 months. WHO susceptibility tests indicated that An. gambiae has developed high level of resistance to pyrethroids and DDT in Ahero, Kisian, Chulaimbo, Emutete, Emakakha, Iguhu and Bungoma. Resistant to bendiocarb in Iguhu and Kabula and susceptible to Malathion (100% mortality) in Ahero, Kisian, Chulaimbo, Emutete, Emakakha, Iguhu and Bungoma. There was an elevation of monooxygenases and esterases enzymatic activities in resistant An. gambiae mosquito populations exposed to Lambdacyhalothrin, Permethrin, Deltamethrin and DDT but no elevation in glutathione s- transferases. A high frequency of L1014S allele was detected in xviii An. gambiae s.s. population but there was no kdr allele found in An. arabiensis mosquitoes. Successive selection for deltamethrin resistance showed a steady increase in the mosquito mortality with 100% mortality in fifth and third generations for Kabula and Ahero mosquitoes respectively. The frequency of the homozygous ss (L1014s) allele was high in the first generation of Kabula mosquito populations but reduced in the subsequent generations. Long lasting insecticide nets should be replaced with new nets every three years and not five years as recommended and also high levels of ITN coverage and usage should be maintained. There is also an urgent need for development and deployment of non-pyrethroid based vector control tools.
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    Anthropogenic Impacts on Distribution and Abundance of Mountain Catfish (Amphilias Uranoscopus, Pfeffer, 1889) and Other Fishes, in the Sagana and Thego Streams, Nyeri, Kenya
    (Kenyatta University, 2019-04) Odhiambo, Charles Oduor
    The clearance of forest for agriculture, settlement and grazing has had some of the most widespread human impacts on natural ecosystems globally. In Kenya large tracks of indigenous forests continue to be cleared to give way for human settlement and exotic tree plantations. The catchment on the slopes of Mt. Kenya has experienced such major losses that have affected the aquatic ecosystem. The objective of this study was therefore to document the extent of impact of anthropogenic activities on the distribution, abundance and population sizes of the mountain catfish (Amphilius uranoscopus Pfeffer, 1889) and other fish species along two second order tropical forested streams, Sagana and Thego on the slopes of Mt. Kenya. This study was done from June 2016 through May 2017. Fish samples were caught using an electrofisher and recorded for distribution, population sizes, reproductive strategies and feeding habits. Water samples for physiochemical parameters were determined in situ and a socio-economic survey of the riparian community carried out using a structured questionnaire. The smallest sized catfish were caught in November 2016 at the Thego station T2 midstream while the largest specimen electrofished was a I9.0 cm fork length (92.19 female caught in the downstream station (T3) of the Thego. There was a significant difference (t-test, t : - 3.35; p:0.007) in the mean number of catfish caught per hour of electrofishing between the Thego stations (T2 and T3). A comparison between Catch per unit effort (CPUE) in Sagana and Thego (ANOVA, F : 6.82; p : 0.004) showed a significant difference in catches between the two streams. Results from this study shows that there have been major significant changes in the distribution patterns of both the native species as well as the salmonid species in the two streams and that the mountain catfish has expanded its territory while the introduced salmonid species zones have shrank or become thin. Catfish exhibited a wider food base overlapping with those of the other species such as rainbow trout, brown trout and barbus. The occurrence of the mountain catfish (Amphilius uranoscopus), Barbus sp. and Labeo sp. inthe midstream of the Thego and downstream of the Sagana and Thego, the absence of rainbow trout in the midstream of the Thego and the restriction of the brown trout to the near pristine reaches of the Sagana at an altitude above 2150 metres are some of the changes that have occurred since 1960s due to the impact of human settlement in the watersheds of streams in the slopes of Mt. Kenya. Major factors associated with the variation in catfish distribution and abundance among the study stations included increased temperatures, elevated stream water conductivity and decline in water discharge. These clearly show that the catfish population is likely to move fuither upstream in Thego than in Sagana unless urgent measures to control human related anthropogenic activities in Thego catchment area are adopted. This study supports the hypothesis that the mountain catfish distributional range will continue to expand at the expense of other fish species unless corrective measures are considered to control anthropogenic human driven settlement activities in the watershed of the Sagana and Thego. Management strategies should focus on the values of the society and recognize that the continuous expansion of mountain catfish home range is an indicator of environmental perturbation arising from change in landuse and increase in human activities.
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    Isolation Serotyping and Molecular Characterization of Enteric Pathogens for Validation of “Peepoo” Sanitization along Handling Chain at Kibera, Nairobi Kenya
    (Kenyatta University, 2018) Nduhiu, Gitahi Johnson
    An estimated 1.8 billion people in the world use water coming from fecally contaminated sources. This is as a result of 80% of the human generated wastewater ending up in rivers and other reusable water bodies before treatment. The hygienic balance is locally complicated by the fact that 57% of people in informal settlements have no access to basic sanitation, including latrines and toilets. This study sought to evaluate alternative toileting in the name of “Peepoo”, as single use personal toilet for human excreta sanitization and reuse as safe fertilizer, thus preventing dissemination of pathogens to the environment. A cross sectional study was conducted to sample 11 schools enrolled in the project working site in Kibera. Using standard microbiological methods, baseline faecal pathogen concentrations were determined as prevalences at the start of sanitisation and used to validate the “Peepoo” bag along handling chain. Specific primers were used for molecular characterization of isolated pathogens and detection of resistant genes. The prevalence of pathogenic bacteria (Salmonella enterica subspecies arizonae IIIa (0.34%), pathogenic Escherichia coli (7%), Campylobacter spp (18.3%), protozoa (Cryptosporidium spp (2.4%), Entamoeba histolytica (28%), soil transmitted helminth (Ascaris lumblicoides (20%) and Trichuris trichura (13%) eggs and gastrointestinal viruses (Rotavirus (0%) and Adenovirus (1.1%), were determined. There was marked difference in parasitism distribution among schools that was attributed to contamination of school compound with raw sewage. The identified bacteria and parasitic pathogens (Salmonella enterica, Escherichia coli, Campylobacter coli, Campylobacter jejuni, Campylobacter coli and Ascaris lumblicodes) in relation to pH, temperature and ammonia concentration were used to validate sanitation ability of the “Peepoo” bag along handling and reuse chain. Pathogenic Escherichia coli (69%) including EHEC (6.0%), EPEC (3.5%), ETEC (2.0%), DEAC (2.0%), EAEC (0.7%), EIEC (0.4%) and Campylobacter jejuni (92%), Campylobacter coli (88%), Campylobacter lari (76.9%) and Campylobacter spp (25%) were genetically identified and found to be resistant to 1st and 2nd generation antibiotics at different levels. Viral infection (Rotavirus and Adenovirus) was not identified as a health issue during the study period. Sequencing of PCR products from selected pathogenic Escherichia coli isolates confirmed their molecular identity. The results from this study demonstrated the ability of “Peepoo” bag to effectively inactivate pathogens found in human excreta when stored for 8 weeks at ambient temperature. This significantly reduced the risk of pathogens internalization by coriander grown in soil fertilized with human excreta. The peepoo bag should therefore be deliberately promoted as a method of human waste management in informal settlements and as alternative source of organic fertilizer. Mass deworming of children is also recommended after every three months in informal settlements.
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    Isolation Serotyping and Molecular Characterization of Enteric Pathogens for Validation of “Peepoo” Sanitization along Handling Chain at Kibera, Nairobi Kenya
    (Kenyatta University, 2018-10) Johnson, Nduhiu Gitahi
    An estimated 1.8 billion people in the world use water coming from fecally contaminated sources. This is as a result of 80% of the human generated wastewater ending up in rivers and other reusable water bodies before treatment. The hygienic balance is locally complicated by the fact that 57% of people in informal settlements have no access to basic sanitation, including latrines and toilets. This study sought to evaluate alternative toileting in the name of “Peepoo”, as single use personal toilet for human excreta sanitization and reuse as safe fertilizer, thus preventing dissemination of pathogens to the environment. A cross sectional study was conducted to sample 11 schools enrolled in the project working site in Kibera. Using standard microbiological methods, baseline faecal pathogen concentrations were determined as prevalences at the start of sanitisation and used to validate the “Peepoo” bag along handling chain. Specific primers were used for molecular characterization of isolated pathogens and detection of resistant genes. The prevalence of pathogenic bacteria (Salmonella enterica subspecies arizonae IIIa (0.34%), pathogenic Escherichia coli (7%), Campylobacter spp (18.3%), protozoa (Cryptosporidium spp (2.4%), Entamoeba histolytica (28%), soil transmitted helminth (Ascaris lumblicoides (20%) and Trichuris trichura (13%) eggs and gastrointestinal viruses (Rotavirus (0%) and Adenovirus (1.1%), were determined. There was marked difference in parasitism distribution among schools that was attributed to contamination of school compound with raw sewage. The identified bacteria and parasitic pathogens (Salmonella enterica, Escherichia coli, Campylobacter coli, Campylobacter jejuni, Campylobacter coli and Ascaris lumblicodes) in relation to pH, temperature and ammonia concentration were used to validate sanitation ability of the “Peepoo” bag along handling and reuse chain. Pathogenic Escherichia coli (69%) including EHEC (6.0%), EPEC (3.5%), ETEC (2.0%), DEAC (2.0%), EAEC (0.7%), EIEC (0.4%) and Campylobacter jejuni (92%), Campylobacter coli (88%), Campylobacter lari (76.9%) and Campylobacter spp (25%) were genetically identified and found to be resistant to 1st and 2nd generation antibiotics at different levels. Viral infection (Rotavirus and Adenovirus) was not identified as a health issue during the study period. Sequencing of PCR products from selected pathogenic Escherichia coli isolates confirmed their molecular identity. The results from this study demonstrated the ability of “Peepoo” bag to effectively inactivate pathogens found in human excreta when stored for 8 weeks at ambient temperature. This significantly reduced the risk of pathogens internalization by coriander grown in soil fertilized with human excreta. The peepoo bag should therefore be deliberately promoted as a method of human waste management in informal settlements and as alternative source of organic fertilizer. Mass deworming of children is also recommended after every three months in informal settlements.
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    Zoonotic gastrointestinal helminths and hemoparasites of baboons in Tana River, Tsavo and Laikipia, Kenya
    (Kenyatta University, 2017-02) Maloba, Fredrick Chimoyi
    Zoonotic pathogens are among the most important causes of ill health in humans all over the world. In Kenya, the encroachment of wildlife habitats has led to increased interaction between humans and non-human primates especially baboons hence potential for zoonoses transmission. However, a risk analysis for these zoonoses had not been undertaken in Kenya. The current study aimed to investigate hemoparasites and gastrointestinal parasites of olive baboons (Papio anubis) at the human–baboon interface in Tsavo West National Park, Tana River Primate Reserve and Mutara Ranch in Laikipia County. Laikipia baboons were used to study hematological responses to helminth treatments and pathology. Questionnaire survey was conducted in Tana River and Tsavo on risk factors associated with zoonoses. Baboons were trapped in the wild, sampled for blood, feacal, ectoparasites and thoroughly examined physically. Blood smears were prepared and examined for hematology and haemoparasites. Uncoagulated blood was used for confirmation of haemoparasites with Polymerase Chain Reaction (PCR). Feacal samples were screened for helminth oocysts. Helminths detected included Oesophagostomum, Strongyloides, Trichuris and Enterobius with the highest frequencies being 80.5%, 77.8%, 27.5% and 14.8% respectively in the three study sites. Schistosoma mansoni was only detected in Tsavo baboons (2.1%). There was a significant difference in prevalence of the helminths among the three sites (P<0.05) with Laikipia having the highest frequencies followed by Tana then Tsavo. Infection intensities were light in all the study sites. Following treatment, all the leucocyte parameters did not change significantly (P<0.05) but there was a significant increase in erythrocyte indices (P<0.05) except MCV (P>0.05) though all were still within normal ranges. Hemoparasites were detected by PCR in Tsavo and Tana River baboons only and these included Hepatocystis kochi (90% and 87%), Babesia (10.8% and 16.7 %,), and Entopolypoides (8.7% and 5%) respectively. There was an association between H. kochi infection and lymph node enlargement as well as fever (χ2>3.84, df=1, P<0.05) in both Tana River and Tsavo baboons. Tissue pathology due to helminth revealed nodular lesions with epithelial necrosis due to Oesophagostomum in large intestines, lung fibrosis due to Strongyloides infection and intussusception attributed to Trichuris infection. Schistosoma mansoni infection revealed granuloma formation, parenchymal and periportal fibrosis in liver. Risk factors of zoonosis in Tsavo and Tana River included sharing of river water (6%, 76%), baboon crop raids (65% and 75.1%) and baboon livestock predation (92.9% and 91.8%), consumption of left overs from crop raids/ predation (66%, 19.8%), lack of knowledge of zoonoses (81% and 92%), monkey meat consumption (12% and 2%) respectively. Significant factors included baboon crop raids, left over consumption, and lack of knowledge on zoonosis (P<0.05) in both sites. There was a high interaction between humans and baboons which increased the risk of zoonoses transmission. Public education on zoonosis, training of health staff on zoonoses and improving compensation due to losses caused by baboons is highly recommended to reduce human-wildlife the interaction and potential for zoonoses transmission.
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    Prevalence of Geohelminthiases and Its Effects on Growth and Cognitive Functions in Pupils in Kibera and Korogocho Slums, Nairobi County, Kenya
    (Kenyatta University, 2017-05) Mwenji, Benedict M.
    Geohelminthiases are infections caused by Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis and Trichuris trichiura leading to oedema, iron-deficiency, protein-energy malnutrition, electrolyte derangement, endocrine upsets and cardio-vascular failure. Resulting sequelae lead to poor health, physical fitness and anaemia. Geohelminthiases is widespread in areas with poor sanitation but empirical data on prevalence and its effects on growth, academic performance and cognitive functions is scanty. The current study aimed at determining effects of geohelminthiases on growth, Cognitive functions and academic performance of children in Kibera and Korogocho slums, Nairobi County. Kasarani (Korogocho slum), Lang’ata (Kibera slum) and Dagoretti (Kibera slum) sub-Counties were purposefully selected. Four schools were selected purposefully using cluster random sampling method: 2 from Kasarani, 1 from Dagoretti and 1 from Lang’ata sub-Counties. Sample size of 470 children in class 2-7 were selected by systematic random sampling method. Kato-Katz technique was used to estimate infection intensity. Point prevalence was determined by comparing total number of infected children against total number of sampled children, expressed as percentage. Information on Cognitive functions was obtained using Word Generation Semantic (WGS), Word Generation Initial (WGI), List Memory (LM), Standard Progressive Matrices (SPM), Coding-B (Cod-B), Symbol Search-B (SS-B) and Digit Span (DSP) tests. Anthropometric measurements were used for computing BMI. Data on absenteeism and academic performance was deduced from class records for 3 terms pre-treatment (400 mgs albendazole) and immediate 2 terms, post-treatment. Stool examination was repeated 3 months after treatment. Questionnaire was administered to collect information on family background to cater for confounders influencing cognitive functions. Pearson’s Product moment correlation was used to determine associations. ttest was used to determine differences between means of infected and non-infected children. ANOVA was used to determine relationships. Linear Regression was used to identify the confounders influencing Cognitive functions. Highest prevalence of geohelminths (51.9%) occurred in Dagoretti sub-County (Kibera slum). Highest prevalence occurred with A. lumbricoides (37.4%) and T. trichiura (33.2%). Highest light and moderate infections (16.5%) and (10.4%), respectively, occurred in 11-14 years-old children. Heavy infections (1.1%) occurred in 6-10 and 11-14 year-old children. Highest absenteeism (44.3%) was in Mbagathi school (Kibera slums) and highest prevalence (51.7%) in Olympic school (Kibera slum). Significant differences in infection intensities occurred between males and females (p < 0.05), with females having higher infections than males. Geohelminthiases negatively affected Growth (r = - 0.809; p < 0.05). Children with low BMI had high infection rates (p < 0.05). Geohelminthiases inversely correlated with Cognitive performance as measured in WGS, WGI, LM, SPM, Cod-B and DSP tests (p < 0.05). Infections positively correlated with Absenteeism (r = 0.971; p < 0.05) and adversely affected Academic performance (r = - 0.879; p < 0.05). Interestingly, chemotherapy with albendazole improved BMI, Cognitive functions and Academic performance. Data generated will support policy on control of geohelminthiases. It is recommend that regular mass-chemotherapy programmes be applied in schools and slum communities to improve children’s general health, growth, school attendance and academic performance.
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    Suitability of Hedgerow Planting System in Managing Bee (Hymenoptera: Apoidae) Pollinators in Farmlands of Kenya
    (Kenyatta University, 2016) Guantai, Mary Mwari
    Bee presence in the farmland is crucial for provision of essential crop pollination service. However, this is highly determined by the availability of forage resources and nesting sites among others. Therefore, the overall aim of this study was to determine suitability of hedgerows in providing bee needs in Kenya. Specifically, the study was carried out to determine i) bee nest presence in farmlands bordering Mt. Kenya, Mt. Kilimambogo and Kakamega forests, ii) the floral richness of hedgerow plants in farmland bordering NW Mt. Kenya forest, and iii) diversity and abundance of bees visiting hedgerows in farmlands bordering NW Mt. Kenya forest. The data were collected through i) excavation and characterization of solitary bee nests along a transect from fields near the forest to fields 15 km away, ii) observation of floral resources for period of 1 year (September 2013 to August 2014) along a transect from fields near the forest to fields 15 km away and ii) observation of bees visiting flowers of hedgerow plants for period of 1 year along a transect from fields near the forest to fields 15 km away. Their presence on hedgerow plants was compared with those present on cropped area and uncropped patches in the field. The number of bee nests was statistically (P
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    Food handlers perception on food safety, occurrence and characterization of enterotoxigenic staphylococcus aureus isolated from foods of animal origin in Nairobi, Kenya
    (2016) Mathenge, John Muriithi
    Diarrheal diseases are the commonest manifestation of food poisoning, which are fatal. Knowledge, attitude and practice of food handlers influence the occurrence of food poisoning. Staphylococcus aureus is considered the third most important cause of food-borne diseases in the world after Salmonella species and C. perfringens. Antimicrobial resistance and enterotoxigenic properties of S. aureus in food of animal origin in many parts of Kenya are scanty. The aim of the study was to investigate food handlers’ perception on food safety and characterization enterotoxigenic S. aureus in foods of animal origin in Nairobi Kenya. A cross-sectional descriptive study was conducted in Nairobi and its environs, confined to meat and milk outlets. In the first stage of the study on food safety, food handlers (n=100) were interviewed and questionnaire administered to assess their knowledge, attitudes and practices (KAP). In the second phase, food samples of animal origin (n=420) were randomly purchased from different outlets. Additional 251 samples of various pork products from a meat processing plant were collected for isolation and characterization of enterotoxigenic properties of S. aureus. Colonies of S. aureus were selected from Baird-Parker medium plates for identification using the biochemical tests. Reverse Passive Latex Agglutination was used to identify enterotoxigenic strains. Gene distributions were detected by multiplex Polymerase Chain Reaction (mPCR) reaction. Their resistance to eight commonly used antibiotics was determined using Kirby-Bauer disc diffusion test. Results on Knowledge, Altitudes and Practices showed that overall scores were not significantly affected by marital status and religion of the respondents. Gender comparisons revealed that the mean KAP scores for men and women food handlers were similar. A total of 251 (37.4%) of S. aureus strains were isolated and identified. The proportions of contamination of animal products from the seller and meat processing plant were comparable. The contamination rate of the meat and meat products sample (40.7%) was significantly higher than milk and milk products (25.0%) (p=0.001). Most of the strains 187 (74.5%) produced staphylococcal enterotoxin (SE) with staphylococcal enterotoxin A (SEA) being the most frequent (90, 48.1%), followed by a combination of SEA and SEC (22, 11.8%). Most frequent gene detected by multiplex PCR was sea (61.8%). Genes see, sed, sec, and seb were observed in 33.3%, 17.5%, 15.9% and 13.9% strains, respectively. Combination genes found to occur in pairs were Sea/See (21.2%), Sea/Sed (9.8%), Sed/See (2.1%), Sea/Sec (0.7%) and Seb/Sec (0.5%). A combinations of four genes sea/sec/sed/see accounted for only 0.01%. Relatively low number (2.1%) of discrepancies between multiplex PCR and Reverse Passive Latex Agglutination (RPLA) assay particularly on SED. The results of both methods were identical concerning SEA, SEB and SEC. All of the strains showed multi drug resistance (MDR) to major classes of antibiotics tested with Penicillin G having the highest resistance level (246, 99.6%) followed by Ampicillin (230, 93.1%). The study concluded that knowledge attitude and practice performance seemed to improve along the level of education and work experience. High level of contamination of foods of animal origin by enterotoxigenic and MDR strains of S. aureus was evident. The study indicates a need for good hygiene practices in food processing, in order to minimize staphylococcal food poisoning, which poses a health risk for the consumers.
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    Assessment of Mangrove Phenology and the Role of Insect Pollinators in Fruit Production at Nyeke and Michamvi Mangrove Forests, Zanzibar
    (Kenyatta University, 2016-05) Ali, Abdalla Ibrahim
    Mangrove forests are evergreen estuarine and open systems which receive nutrients, fresh water and sediments from terrestrial environments. They vary both in their salinity tolerance and the degree to which salinity may be necessary to maintain their growth and competitive dominance. Mangroves grow throughout the tropics wherever the average monthly minimum temperature is at least 200C. The ecological importance of mangroves are due to the ecosystems’ ability to maintain marine life, their high productivity and role in supplying organic material to other coastal marine ecosystems as reported by many studies. Mangroves trees have been proven to be very important in the mangroves ecosystem. Anthropogenic activities have been shown to be the primary cause of mangrove depletion worldwide. Rising mangroves forest destruction has negatively impacted on pollinator diversity and fruit set significantly. However, little is known about the magnitudes of these issues in East Africa. This research was therefore designed to assess diversity and abundance of mangrove insect pollinators and their role in fruit set in four mangrove species at Nyeke and Michamvi mangrove forests, Zanzibar. The study was conducted in two mangrove sites in South region of Zanzibar, Nyeke mangrove forest located between 60 19’ and 60 24` S and 390 25` E, and Michamvi mangrove forest located between 60 14’ S and 390 49’ E. The distance between the two sites is approximately 25km. Four mangrove species which are pollinated by insects (Rhizophora mucronata, Bruguiera gymnorhiza, Ceriops tagal and Avicennia marina) selected from Nyeke and Michamvi mangroves forests were used in the study. The reproductive phenology, reproduction relationships of mangroves, pollinator species diversity and richness, and effect of pollination on fruit set were investigated. The study found that reproductive phenology varied among species and sites. The peak fruit set varied among species and sites. There was a positive relationship between temperature and reproduction but not with rainfall and relative humidity. In both sites the findings showed a weak relationship between fruit set and number of fruits. The study also revealed that increase in number of insect flower visitors and visits did not result in increased fruit sets. However, increase in number of flowers increased the number of insect flower visitors and visits. A total of 18029 insect flower visitors representing 70 species in 7 orders and 40 families were observed visiting flowers of the four mangrove species in both sites. Family Apidae of the order Hymenoptera was the most common and insects of this order were found in all four mangroves species. Apis mellifera was the most dominant flower pollinator for Bruguiera gymnorhiza, Ceriops tagal and Avicennia marina. Hypotrigona gribodoi was predominantly found on RM and is potentially the flower pollinator of this species. Higher number of Apis mellifera 721 (32.2%) was recorded in Bruguiera gymnorhiza at Nyeke site. Bagged experiment that prevented most pollinators accessing the flower, showed a high percentage of flower abortion and lowest fruits produced than other treatments in this study. A. marina had confirmed lower fruit set compared to the other species. Pollen Supplement (PS) (hand cross pollination) produce higher percentage of fruits set and fruits in some mangroves species in both sites. This not only shows that additional pollen enhances fertilization but also that pollination is necessary for fruit production. The study concludes that, in depth research on various variables of mangroves including inventory of pollinators, biodiversity, social economic significance, potential threats and phenology for other species and climate alteration are important for strengthen biodiversity conservation and mitigation.