School of Science, Technology and Engineering

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Integrity of 130 kDa polypeptide of Bacillus thuringiensis var israelensis delta-endotoxin in K-S defined (sporulation) medium
(ICIPE, 1992) Otieno-Ayayo, Z. Ngalo; Chipman, David M; Zaritsky, Arieh; Khawaled, Kamal
Enduring toxicity of transgenic Anabaena PCC 7120 expressing mosquito larvicidal genes from Bacillus thuringiensis ssp. israelensis
(National Library of Medicine, 2003) Otieno-Ayayo, Z. Ngalo; Manasherob, Robert; Miaskovsky, Rina; Ben-Dov, Eitan; Boussiba, Sammy; Zaritsky, Arieh
Persistence of biological control agents against mosquito larvae was tested under simulated field conditions. Mosquito larvicidal activity of transgenic Anabaena PCC 7120 expressing cry4Aa, cry11Aa and p20 from Bacillus thuringiensis ssp. israelensis was greater than B. thuringiensis ssp. israelensis primary powder (fun 89C06D) or wettable powder (WP) (Bactimos products) when either mixed with silt or exposed to sunlight outdoors. Reduction of Bactimos primary powder toxicity was at least 10-fold higher than Anabaena’s after mixing with silt. In outdoors experiments, Bactimos WP remained toxic (over 30% mortality of 3rd instar Aedes aegypti larvae) for 2–4 days only, while transgenic Anabaena’s toxicity endured 8–21 days.
Micronutrient Zinc Deficiency as a Possible Co-factor in the Transmission and Progression of HIV/AIDS in Kenya
(2004) Mbakaya, Charles; D Bulimo, Wallace; Jumba, Isaac; Nyambaka, Hudson Nyabuga
Thirty-four HIVIAIDS patients at various stages of disease progression volunteered to manage their ealth using a nutritional supplement that contained several micronutrients that included a 15 mg daily dose of elemental zinc. This initial publication only focuses on trends in the serum zinc levels and the observed biochemical changes following intervention, considering the critical role this trace element plays in human immunity. At baseline and after 30 months of follow-up, the patients' serum zinc levels were determined as was their clinical status. Four women who were found to be HIV negative at baseline and who had lost their husbands to HIVIAIDS et they had regularly had un-protected sex ' Y+ with them, had a mean serum zinc level of 116.2 -32.7 mcg1100 ml. The serum zinc levels of asymptomatic, moderately symptomatic and severely symptomatic HIVIAIDS patients in the cohort reduced from baseline to post intervention levels of 92.5512.1 to 78.0 2 8.2 mcg1100 ml (P = 0.056); 81.92 17.6 to 73.2 5 12.2 mcg1100 ml (P =0.267) and 72.7+ 8.0 to 66.8 2 14.3 mcg1100 ml (P = 0.022), respectively, all being far below the mean serum zinc level of 120.0 + 22.0 mcg1100 ml reported in normal control subjects in Western literature. For all patients combined, the serum zinc levels fell from 79.2 2 14.5 to 71.0 5 13.0 mcg1100 ml (P= 0.016) notwithstanding that the patients had used zinc supplements at recommended daily allowances (RDA) over a period of 30 months. Notably, micronutrient zinc sufficiency plays a key role in promoting cell-mediated immunity and it is probably partly due to this reason that the high-risk women in this study, who also had comparably high serum zinc levels, remained negative for HIV antibodies despite repeated exposure to the virus. Thus, from this preliminary data that shows HIVIAIDS patients to be deficient in zinc in a manner consistent with their status of disease progression and considering that this trace element is recognized to possess antiviral and antibacterial properties, it is now apparently evident that zinc supplementation may play a key role in the fight against HIVIAIDS not only in Kenya but also in other African countries where this disease has reached epidemic proportions against a background of rampant malnutrition.
Institutional pluralism, access and use of wetland resources in the Nyando Papyrus Wetland, Kenya
(Academic journal, 2005) Nasongo, A. A Serena; Zaal, Fred; Dietz, Ton; Owuor, J. B. Okeyo
Wetlands support livelihoods of communities living around them as in the Nyando Papyrus Wetland in Kenya. The Nyando Papyrus Wetlands provide multiple resources hence there are multiple uses and users who often overlap spatially and seasonally causing conflicts. More claims are being exerted on these wetland resources from different sides and institutional levels with different actors. The actors involved refer to various legal systems and mechanisms, and frequently create new hybrid law as in the case in the Nyando papyrus wetlands. These institutions, in various degrees of transformation, still have an important role in determining how resources are used. The objective of this study is to find out about the institutions affecting wetland resource use in the past and in the present and to determine the dynamics of specific natural resource-related institutions in four sub-locations in the Nyando Papyrus Wetlands, Kenya. The study shows that there is legal pluralism in the Nyando Wetlands, which requires synergy for sustainable livelihoods in the local communities and for ecosystem management.
Changes in population characteristics and diet of Nile tilapia Oreochromis niloticus (L.) from Nyanza Gulf of Lake Victoria, Kenya: what are the management options?
(Tylor&Francis, 2007-11-26) Owuor, J.B. Okeyo; M. Muchiri; M. van der Knaap; I. G. Cowx
Length frequency data collected from 1998 to 2001 from commercial landings was used to estimate asymptotic length (L∞), growth coefficient (K), mortality (Z, F, M), growth performance index (φ ) and exploitation rate (E) of Oreochromis niloticus from the Nyanza Gulf of Lake Victoria, Kenya. Studies on the diet of O. niloticus collected by demersal trawl and seining between 1998 and 2000 were also conducted. Length frequency data were analyzed using the FISAT software (an FAO-ICLARM Stock Assessment Tool package). The L∞ had a mean value (±S.D) of 58.78 ± 2.42 cm TL, K of 0.59 ± 0.05 yr−1, Z of 2.16 ± 0.40 yr−1, M of 1.00 ± 0.06 yr−1, F of 1.12 ± 0.34 yr−1, E of 0.48 ± 0.11 and φ of 3.31 ± 0.04. Length at first entry into the fishery (L50) was observed at 26.18 ± 12.50 cm TL. Recruitment occurred throughout the year, with two peaks corresponding with the rainy seasons. A comparison with previous studies in the gulf indicates that O. niloticus is now caught at a smaller mean size, whereas K, Z, and M have increased. Fish appeared to become sexually mature at a smaller size. Nile tilapia originally known to be herbivorous, feeding mostly on algae, has diversified its diet to include insects, fish, algae and plant materials, all being important food items. The changes in population characteristics and diet of O. niloticus are discussed in context of changes occurring in the lake and its surroundings.
Variations in the mosquito larvicidal activities of toxins from Bacillus thuringiensis ssp. israelensis
(2008) Otieno-Ayayo, Z. Ngalo; Zaritsky, Arieh; Wirth, Margaret C.; Manasherob, Robert; Khasdan, Vadim; Cahan, Rivka; Ben-Dov, Eitan
Comparing activities of purified toxins from Bacillus thuringiensis ssp. israelensis against larvae of seven mosquito species (vectors of tropical diseases) that belong to three genera, gleaned from the literature, disclosed highly significant variations in the levels of LC50 as well as in the hierarchy of susceptibilities. Similar toxicity comparisons were performed between nine transgenic Gram-negative species, four of which are cyanobacterial, expressing various combinations of cry genes, cyt1Aa and p20, against larvae of four mosquito species as potential agents for biological control. Reasons for inconsistencies are listed and discussed. Standard conditions for toxin isolation and presentation to larvae are sought. A set of lyophilized powders prepared identically from six Escherichia coli clones expressing combinations of four genes displayed toxicities against larvae of three mosquito species, with levels that differed between them but with identical hierarchy.
Macroinvertebrate-based Index of biotic integrity (M-IBI) for monitoring the Nyando River, Lake Victoria Basin, Kenya
(Academic journal, 2009-12) Okoth Raburu, Phillip; Owuor, J. B. Okeyo; Onderi Masese, Frank
A macroinvertebrate-based Index of Biotic Integrity (M-IBI) was developed to monitor ecological integrity of the Nyando River and its tributaries. Macroinvertebrates were sampled with a scoop net between September and December 1999 from 12 stations selected to correspond with different human activities in the catchment. The samples were hand sorted in the field, preserved in 70% alcohol before transportation to the laboratory for identification and counting. The stations were grouped into three condition categories (reference, moderate and impaired) according to the level of water and habitat quality. Twenty metrics representing the structural and functional organization of macroinvertebrates were evaluated for range, response to disturbance and stream size differences and redundancy with each other. Ten metrics met the test criteria and were used to provide the final scores for developing the M-IBI. Metrics values at both reference and impaired sites were used to establish the scoring criteria using inter-quartile ranges. The metrics displayed variability across the sites and the final index was able to separate reference sites from moderately impaired and impaired sites. There were variations in ecosystem integrity among stations and this was reflected in community composition and structure of resident macroinvertebrates. The index developed can, therefore, be used to monitor the integrity of streams within the Nyando River Basin.
Might the time be right to re-define the cause of AIDS in the light of emerging evidence?
(2011) Mbakaya, Charles; Nyambaka, H.; Waudo, J.; Ndiege, I. O.
Response of three mosquito species to recombinant bacterial toxins from bacillus thuringiensis subsp. Israelensis expressed in two model systems
(Baraton Interdisplinary Research Journal, 2012) Otieno-Ayayo, Z. Ngalo; Eitan, Ben-Dov; Rivka, Cahan; Manasherob, Robert; Zaritsky, Arieh
Toxicity of lyophilized powders prepared prepared 16 combinations of four genes, cry4Aa, cry11Aa, cyt1Aa and p20 from Bacillus thuringiensis subsp.israelensis (Bti) expressed in Escherichia coli were examined against three mosquito vectors of diseases, Culex quinquefasciatus Say, Anopheles arabiensis Patton, and Aedes aegypti Linnaeus, followed by simulated studies using transgenic Anabaena PCC7120 expressing the most toxic combination of genes. The following clones were the most toxic to the three mosquito species: pVE4- ADRC expressing all four genes (LC50s of 0.59, 3.2, and 0.68 μg ml-1); pVE4-ARC expressing cry4Aa, cyt1Aa, p20 (LC50s of 0.93, 6.2 and 0.87 μg ml-1), and pVE4-AD expressing cry4Aa and cry11Aa (LC50s of 1.51, 7.5 and 1.3 μg ml-1). The clone pVE4-ADRC was undoubtedly the most effective. The role of appropriate promoter(s) in enhancing toxicity was demonstrated by comparing expression of the same gene combination under a strong E. coli promoter (PA1) either singly, in pVRE4-DRC or two (the second preceding cyt1Aa in pVE4- DRC). The latter produced more Cyt1Aa, which is less toxic, at the expense of the more toxic Cry11Aa, thus reducing toxicity. On the other hand, the combination of toxins under pVRE4-DRC control had an enhanced toxicity. This observation implies that further toxicity fine-tuning could be reached by manipulating promoters to enhance toxicity in recombinant systems. In simulated semi-field experiments, transgenic Anabaena PCC 7120 protected the toxins from premature degradation and better delivered the toxins to the larvae compared to commercial Bti preparations.
Factors contributing to bacterial diversity and load in Bulawayo restaurants, Zimbabwe
(Baraton Interdisplinary Research Journal, 2012) Otieno-Ayayo, Z. Ngalo; Siband N.; Siband M.M.
An analysis of factors contributing to bacterial diversity and count was done on Bulawayo restaurants. Focus was on equipment, foods, personnel and working surfaces. Twenty five restaurants were selected using simple random sampling, 57 (n=57) food handlers and 25 (n=25) supervisors responded to questionnaires. MINITAB was used for data analysis, employing multiple regression and analysis of variance. Findings revealed that, males are better food handlers than females (t=- 2.86) Facility, supervision, manager’s experience medical checks ups, gender and inspection by Environmental Health Officers had a highly significant influence on laboratory overall results with a p value of 0.000 (p=0.01). Hypotheses 3, 4 and 5 were rejected at 0.01 level of significance. Food service personnel and the environment represent the main sources of contamination.
Selling Sprinkles micronutrient powder reduces anemia, iron deficiency, and vitamin A deficiency in young children in Western Kenya: a cluster-randomized controlled trial
(2012) Mbakaya, Charles; Ruth, Laird J; Woodruff, Bradley A; Mandava, Usha; Ayala, Rafael Flores; Jefferds, Maria Elena D; Quick, Robert
Background: Although the efficacy of micronutrient powders [MNPs; eg, Sprinkles MNP (Sprinkles Global Health Initiative)] in the reduction of anemia has been established, the effectiveness of these powders in real-world programs has seldom been assessed. Objective: In this study, we evaluated the effect of community-based marketing and distribution of Sprinkles MNP on childhood rates of anemia and iron and vitamin A deficiency. Design: In a cluster-randomized trial in children aged 6–35 mo in Western Kenya, 60 villages were randomly assigned to either intervention or control groups. Community vendors marketed and sold sachets of Sprinkles MNP in intervention villages. Biweekly household visits monitored the use of Sprinkles MNP. Hemoglobin, ferritin, retinol binding protein, malaria, and anthropometric measures were assessed at baseline (n = 1063) and 12 mo of follow-up (n = 862). Data were analyzed by using an intention-to-treat analysis and generalized linear mixed models. Results: On average, 33% of households in intervention villages purchased Sprinkles MNP; the average weekly intake per child was 0.9 sachets (∼11.3 mg Fe and ∼328 μg vitamin A). Compared with control subjects, intervention children had greater improvements in hemoglobin concentrations (increase of 0.9 compared with 0.6 g/dL, respectively; P = 0.02), iron deficiency (decrease of 19.3% compared with 5.3%, respectively; P = 0.001), and vitamin A deficiency (decrease of 7.5% compared with an increase of 2.5%, respectively; P = 0.01). Results adjusted for age, sex, socioeconomic status, and maternal education showed a significant association between the hemoglobin, iron, and vitamin A concentrations of children and the number of Sprinkles MNP sachets the children consumed. The prevalence of malaria, wasting, and stunting did not change significantly in either group. Conclusion: Even with relatively low and infrequent use, Sprinkles MNP sales through community vendors were associated with decreased rates of anemia and iron and vitamin A deficiency in children in a resource-poor setting. This trial was registered at clinicaltrials.gov as NCT01088958.
Knowledge, attitudes and practices of trained traditional birth attendants on hiv/aids, Kenya
(Baraton Interdisplinary Research Journal, 2012) Otieno-Ayayo, Z. Ngalo; G.C. Seroney; Minnie, K; F.M, Mulaudzi; E Nyangena
HIV and AIDS is a global pandemic with cases being reported from virtually every country in the world. There is a growing awareness in many African countries that the Trained Traditional Birth Attendants (TTBAs) have a major role to play in the transmission and prevention of HIV and AIDS. This is because of the bigger proportion of TTBAs attending to mothers at birth compared to trained health workers. The purpose of the study was to determine the knowledge, attitudes and practices of TTBAs on HIV/ AIDS transmission and prevention.A cross sectional survey was conducted.The study population consisted of 64 TTBAs from Kosirai Division, Nandi Central, Kenya. Structured questionnaires were used to collect data on knowledge, attitudes and practices on HIV/AIDS transmission and prevention from August 15 to September 11, 2008. The study revealed that TTBAs had good knowledge, tend to have positive attitudes, and safe practices on HIV/AIDS transmission and prevention. There exist significant relationships between knowledge and practices (p=.018), and practices and attitudes (p=.022) of TTBAs on HIV/AIDS transmission and prevention, but there is no significant relationship between knowledge and attitudes (p=.994) of TTBAs on HIV/AIDS transmission and prevention. Considering the roles of TTBAs in maternal child health as revealed by this study, the study therefore recommends to the government and non-governmental organization to appreciate the role of the TTBAs in health care delivery system.
Diversity of Sorghum (Sorghum bicolor L. Moench) Germplasm from Tanzania
(2014) Ringo J.H.; Mneney E. E; Onkware, Augustino; Owuoche J. O; Were, Beatrice Ang’iyo; Too, E.J; Gudu, Samuel
Sorghum (Sorghum bicolor L. Moench) is an important cereal crop cultivated in varied agro-ecological zones of Tanzania ranging from the southern highlands to coastal lowlands. Different cultivars and varieties of sorghum are needed for cultivation in such varied zones. Phenotypic properties of Tanzanian sorghums are not wellstudied. Objective of this study was to phenotype some sorghum germplasm from Tanzania using morphological markers to establish their diversity for future use in breeding programs. Ninety-eight sorghum genotypes were evaluated at Bumala and Amagoro in Western Kenya during 2009 and 2010 seasons in a randomized complete block design. The International Plant Genetic Resource Centre descriptors of 1993 were used for data collection. Accession MCSR T29 was the earliest which took only 64 days while MCSR T80 was the latest taking 86 days to attain 50% flowering compared to the overall mean of 71 days. The MCSR T71 was the best yielder (114.6 g/ panicle) and MCSR T10 was the lowest (10.3 g/panicle) compared to overall mean of 92.4g/panicle. About 60% of the sorghums had brown and only 2.2% had black grains. MCSR T90 had bold grains with 1000 seed weight of 55.2g. Leaves per plant ranged from 7 in MCSR T69 to 17 in MCSR T25. Plant height ranged from 72.8 cm in MCSR T53 to 434.6 cm in MCSR T80. This study showed that, Tanzanian sorghums are diverse therefore could be used in future breeding programs for developing multipurpose and adapted cultivars
The silver cyprinid Rastrineobola argentea as the main diet source for rearing Anopheles arabiensis mosquitoes
(Journal of Mosquito Research, 2014) Otieno-Ayayo, Z. Ngalo; J O, Yugi; Ochanda, H; WR, Mukabana
Background & objectives: All organisms that are cultured for laboratory bioassays need food for sustenance and amplification of the colony to such numbers that would not compromise the progress of the research at hand. For effective turnover rate in the population generation, the diet should be such that it is readily available and provide adequate nutrients to the organisms. The aim of this study was to test and evaluate the efficacy of Rastrineobola argentea as a diet source for rearing Anopheles arabiensis Patton mosquitoes for research. Methods: Crushed fish, Rastrineobola argentea and two other commercial larval feeds (Tetramin Baby fish food and baker’s yeast) were compared for their efficacy as diet sources for feeding Anopheles arabiensis mosquito larvae. The effects of these diet types were determined against fecundity, size, longevity and male mating competitiveness. Results: Mosquitoes raised on Tetramin Baby fish food laid larger egg batches (66.45 ± 5.03 mm) as compared to crushed fish (64.86 ± 4.93 mm) or bakers’ yeast (50.49 ± 4.25 mm). However, the number of eggs laid by the mosquitoes irrespective of the diet type did no differ significantly (p < 0.132). Mosquitoes raised on Tetramin Baby fish food were larger in size (3.06 ± 0.02 mm) as compared to those raised on crushed R. argentea (2.93 ± 0.01 mm) or baker’s yeast (3.00 ± 0.02 mm). The choice of diet was found to influence both mosquito size (p < 0.001) and fecundity (p < 0.013). Conclusion: This study found that crushed R. argentea is an effective mosquito larval diet and that it has the potential of being more effective than tetramin if refined further and supplements added.
Prevalence of malnutrition among preschool children (6-59 months) in Western Province, Kenya
(American Institute of Science, 2014) Mbakaya, Charles; Kisiangani, Isaac; Makokha, Anzelimo; Magu, Dennis
Malnutrition being one of the major public health problems in developing countries, it is still unacceptably high and progress to reduce it in most regions of the world is low. In Eastern Africa region, stunting and being underweight is estimated at 48 and 36% and are expected to increase over the next decade. There is limited information available on the prevalence of malnutrition in this area. This study determined nutritional status, and examined correlates of stunting among the children. This was a cross-sectional study undertaken among 125 preschoolers in western province, drawn from 37 clusters. For each cluster a total of 10 households were selected using systematic simple random sampling. Data were collected on nutritional status, socioeconomic status, food consumption and current malaria infection status. The prevalence of stunting (Z-scores for height for age [HAZ] <-2), wasting (Z-scores for weight for height [WHZ] < -2) and being underweight (Z-scores for weight for age [WAZ] < -2) was 28.9, 1.7 and 6.6%, respectively. Stunting was associated with poverty (OR=4.29, 95% CI: 1.06-17.36, p= 0.037) and lack of consumption of solid foods that include ripe mangoes, pawpaw and guavas (OR=3.15, 95% CI: 1.11-8.94, p=0.025), fish (OR=4.1, 95% CI: 1.15-14.61, p=0.021) and eggs (OR=4.42, 95% CI: 0.97-20.08, p=0.039). Child growth is a good indicator of nutritional status of both the individual and the community. The study demonstrates a high prevalence of stunting. Given the acute and long term consequences of malnutrition, interventions aimed at reducing child malnutrition in such a population should focus on all children less than 5 years of age.
Assessment of microbiological contaminants in community water sources in lower Nyakach Division, Kisumu County, Kenya
(Elixir, 2014-09-04) Olal, B.A; Owuor, J. B. Okeyo; Tsingalia HM; Odipo Osano
The importance of water as a vehicle for spreading diseases has long been recognized and many studies have demonstrated the relationship between illness and deficiencies in water supply and sanitation. This study was conducted between October 2008 and July 2009, to determine microbiological water contaminants and related human health problems in community water sources in Lower Nyakach division, Kisumu County. Water samples were collected in selected water points, analyzed using membrane filter technique and their level of microbiological contamination determined using Escherichia coli type I as bio-indicator. Household level surveys and key informant interviews were conducted and secondary data obtained from Pap-Onditi district hospital on cases of environmental and human health risks associated with water contamination. Data from field samples and survey were analyzed usingthe Statistical Package for Social Sciences. Multiple comparisons between sites were made by Analysis of Variance (ANOVA) and the student t-test. Statistical significance was assessed at p ≤ 0.05. The mean counts for faecal coliforms were lower than that of total coliforms in all samples in both dry and rainy seasons although the mean counts total coliforms were higher during the rainy season than the dry season. Water samples from water impoundments showed significant differencesin total coliforms compared to recommended WHO levels and no significant differences for faecal coliforms (α = 0.05). Water samples from shallow wells showed significance difference for faecal coliforms between three sampling sites (Pap-Onditi, Urudi and Bonde). From the survey and hospital findings typhoid fever and amoebic dysentery were the most common water-borne diseases in the study area. Faecal contaminated water possesses high human health risks which are responsible for the reported increased water-borne diseases. The study concludes that total and faecal coliforms are important parameters in monitoring faecal contamination and water quality in the area. Most of the community water sources are seasonal and largely contaminated. Consequently, frequent monitoring of water quality and levels of contaminants using total and faecal coliforms is recommended at common water points to curb potential health related risks.
Perception of Constructivist Learning Environment: Gender and School Type Differences in Siaya County, Kenya
(2014-12-17) Ongowo, Richard Owino.; Indoshi, Francis C.; Ayere, Mildred
Aims: The study aimed at investigating gender and school type differences in perception of Biology constructivist learning environment. Study Design: The study adopted a survey design. Place and Duration of Study: The study was carried out in Siaya County in Kenya between October and November 2013 during the school term. Methodology: The study sampled 815 grade 12 students (466 boys, 349 girls, 399 high achieving students and 416 low achieving students). Two instruments were used viz. Learners Perception Questionnaire (LPQ) and Learners Interview Guide (LIG). The data were analyzed using descriptive statistics, independent sample t-tests, two-way MANOVA and two-way ANOVA. The qualitative data were used to explain quantitative data. Results: The findings show that there existed statistically significant difference in perception between the low achieving schools and high achieving schools in favor of the low achieving schools in all the subscales of SPQ (p =.00) and statistically significant gender (Hotelling’s trace = .131, F = 21.19, p = .000) and school type (Hotelling’s trace = .269, F = 43.48, p = .000) differences with respect to the collective dimensions of the SPQ. The results also revealed that there was an interaction between gender and school type and vice versa with respect to collective dimensions of the SPQ (Hotelling’s trace = .176, F = 23.40, p = .000). Conclusion: It is concluded that low achieving schools have higher preference for a constructivist learning environment than high achieving schools and there exists gender and school type differences in perception of constructivist learning environment in favor of girls and low achieving schools respectively. The implications of the findings are discussed.
Larviciding potency of water and ethanol extracts of Phytolacca dodecandra (L’ Herit) on Anopheles gambiae (Diptera: Culicidae)
(BIO publisher, 2015) Jared Owiti, Yugi; Joash Barack, Okeyo Owour; Caleb Auma, Awiti; Jacqueline India, Juma; Pamela, Were Kogogo; Vulule, John M.; John, . M
Introduction: Plant extracts are an attractive target for search of effective malaria vector control agents. The reason for this is that they present a cost effective, target specific and bio-degradable insecticides. The other reason is that they posses varied phytochemical contents that vectors are unlikely to develop resistance to very soon. In this study, we report on effectiveness of ethanol and water extracts of Phytolacca dodecandra (L’ Herit) against Anopheles gambiae (Diptera: Culicidae) larvae. Methods: Crude ethanol and water extracts of leaves (shoot and midsection) and mature green fruits of P. dodecandra were scrutinized for larvicidal activity against 1st to 4th instar larvae of An. gambiae. Larvicidal bioassays were conducted and effectiveness evaluated using the >80% as per the WHO methods and threshold respectively. ANOVA analyses were performed for statistical justifications of the larvicidal property with P considered significant at p < 0.05. The effects of the extracts were evaluated under laboratory conditions. Result: Ethanol extracts were more potent than water extracts of P. dodecandra as larvicide. The highest mortality (56%) was recorded for L4s for ethanol extracts of mature green fruits of Endod sourced from Eldoret. Water extracts of Neem leaves killed 31% L3s while deltamethrin killed over 80% of all exposed larvae. Conclusion: Ethanol extracts P. dodecandra killed more of the exposed An. gambiae larvae than water extracts. Recorded mortalities due to exposure to the extracts were less than the WHO threshold of >80%. We recommend that additional refinement and tests need to be done before commercial exploitation as a malaria vector larvicide.
Prevalence of Anaemia and Associated Factors Among Preschool Children (6-59 Months) in Western Province, Kenya
(American Institute of Science, 2015) Mbakaya, Charles; Kisiangani, Isaac; Makokha, Anzelimo
Background: Anaemia is the most prevalent nutritional deficiency globally and of major public health concern in preschool children and pregnant women in developing world. In Kenya current anaemia rates are about 69 % among preschool aged children. Anaemia has adverse health consequences in the children. Objectives: To evaluated the prevalence, severity and risk factors of anaemia in preschool children in an area with intense malaria transmission. Design: Cross-sectional study. Setting: Clusters in an area with intense malaria transmission in western Kenya. Subjects: A total of 125 preschoolers were enrolled aged between 6-59 months. Results: The prevalence of anaemia (Hb<11.0 g/dl) was 25%. It was further divided into moderate (14.2%) and mild (10.8%).Higher risk of presenting anaemia was documented for boys, lower household socioeconomic status, malaria infection and anthropometric deficits. Conclusion: The findings show occurrence of anaemia among preschool children. In addition to malaria, low socioeconomic status, anthropometric deficits, sex are important contributors to the pathogenesis of anaemia in Western province. Improving the case management of malaria is likely to reduce the burden of anaemia. Also to implement effective public health interventions to prevent anaemia in this group, an integrated approach that addresses poverty, nutrition and malaria infection is a must.
Assessment of the Impact of Urban Runoff from Migor i Town on the Concentration Levels of Selected Heavy Metals i n Migori River, Kenya
(Journal of Environment and Earth Science, 2015) Olal, Francis Ongachi
Water pollution and decreasing water quality is a major threat to water resources in urban set ups in the developing world. The key culprits include; agricultural runoff, untreated industrial and domestic wastewater, storm water and urban runoff. Migori is a rapidly growing city in Kenya with various land uses including crop and animal farming, industries, municipal markets, and commercial and residential set ups. The large volumes of urban runoffs generated in the town and its environs wash large pollutant loads into Migori River which is the main source of water in the region. This study investigated the effect of urban runoff from Migori town and its environs on the water quality of Migori River in terms of selected heavy metals. Water samples were collected from six established sampling stations along the river for six months (in wet and dry seasons). The water quality values were summarized as mean ± SE. Results indicated continued adverse impacts on the water quality of Migori River by urban runoffs. Water quality impairment in the river increased downstream – towards the town. Lead and nickel concentration levels are way above the WHO recommended guidelines for surface waters. Thus the river water poses serious risks to humans, animals and aquatic life. There is need for public awar eness regarding the pollution problems and the consequences arising thereof in Migori River. There is also need for a study cataloguing the different chemicals used by d ifferent factories within Migori town. This will hopefully establish the definite sources of the heavy metals and nutrients and control their concentrations before they become too high andharmful to the ecosystem. Keywords: Urban run-off, Migori, water quality, pollution

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