Christopher Khayeka-Wandabwa - ITROMID-KEMRI

Christopher Khayeka-Wandabwa

Christopher Khayeka-Wandabwa - ITROMID-KEMRI

Christopher Khayeka-Wandabwa

Publications

30Publications

275Reads

1689Profile Views

24PubMed Central Citations

Determinants of breast cancer early detection for cues to expanded control and care: the lived experiences among women from Western Kenya.

BMC Womens Health 2018 06 1;18(1):81. Epub 2018 Jun 1.

School of Pharmaceutical Science and Technology (SPST), Health Science Platform, Tianjin University, 92 Weijin road, Nankai District, Tianjin, 300072, People's Republic of China.

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http://dx.doi.org/10.1186/s12905-018-0571-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5984781PMC
June 2018
9 Reads
1.660 Impact Factor

Experimental therapeutic assays of Tephrosia vogelii against Leishmania major infection in murine model: in vitro and in vivo.

BMC Res Notes 2017 Dec 6;10(1):698. Epub 2017 Dec 6.

Centre for Biotechnology Research and Development (CBRD), Kenya Medical Research Institute (KEMRI), P.O Box 54840, Nairobi, 00200, Kenya.

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http://dx.doi.org/10.1186/s13104-017-3022-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5718069PMC
December 2017
15 Reads

H3Africa AWI-Gen Collaborative Centre: a resource to study the interplay between genomic and environmental risk factors for cardiometabolic diseases in four sub-Saharan African countries

https://doi.org/10.1017/gheg.2016.17

Global Health, Epidemiology and Genomics

Africa is experiencing a rapid increase in adult obesity and associated cardiometabolic diseases (CMDs). The H3Africa AWI-Gen Collaborative Centre was established to examine genomic and environmental factors that influence body composition, body fat distribution and CMD risk, with the aim to provide insights towards effective treatment and intervention strategies. It provides a research platform of over 10 500 participants, 40–60 years old, from Burkina Faso, Ghana, Kenya and South Africa. Following a process that involved community engagement, training of project staff and participant informed consent, participants were administered detailed questionnaires, anthropometric measurements were taken and biospecimens collected. This generated a wealth of demographic, health history, environmental, behavioural and biomarker data. The H3Africa SNP array will be used for genome-wide association studies. AWI-Gen is building capacity to perform large epidemiological, genomic and epigenomic studies across several African counties and strives to become a valuable resource for research collaborations in Africa.

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November 2016
85 Reads

Strengthening Integrated Zika Virus Epidemics Prevention and Aedes Mosquito Management and Containment Programs Innovations in Africa

J Mol Pathol Epidemiol. 2016, 1:1.

Journal of Molecular Pathological Epidemiology

With over 72 countries and territories affected worldwide with Aedes mosquito-transmitted Zika virus disease and estimated over millions of people are at high ZIKV risk including pregnant women in these Aedes mosquito-prone settings. The recent epidemic events further stress the everincreasing need and value of national public health evidence-based decision-making policy, budget allocation and programs in protecting vulnerable communities. This paper highlights Aedes vector ecological determinants and impacts mitigation and adaptation approaches in strengthening and in scaling-up integrated Aedes mosquito management programs and ZIKV epidemics prevention and containment measures across Aedes-prone African countries. The paper advocates for the urgency to establish and strengthen effective and robust local and national public health laboratories surveillance and inter-sectorial monitoring capabilities in scaling-up evidence-based and integrated Aedes vector management programs and Zika virus (ZIKV) preparedness and emergency response capacity and activities. This paper provides the prerequisite in scaling-up integrated cost-effective Aedes vectors community awareness and empowerment in risk alertness and communication strategies, and Zika virus populationbased detection, diagnosis and reporting systems in guiding evidence-based epidemiologic, clinical and environmental programs implementation innovations at all levels in vulnerable countries such as Africa. Moreover, improving shared responsibility and participation are vital. Furthermore, instituting robust, effective and sustainable local/national preparedness and emergency response systems capacity is crucial in existing and future arthropodborne threats and disasters.

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October 2016
4 Reads

Interlinkage among cardio-metabolic disease markers in an urban poor setting in Nairobi, Kenya.

Glob Health Action 2016 9;9:30626. Epub 2016 Feb 9.

African Population and Health Research Center, Nairobi, Kenya.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4749862PMC
http://dx.doi.org/10.3402/gha.v9.30626DOI Listing
August 2016
9 Reads
1 Citation
1.650 Impact Factor

Analysis of Patterns of Physical Activity and Sedentary Behavior in an Urban Slum Setting in Nairobi, Kenya.

J Phys Act Health 2016 08 21;13(8):830-7. Epub 2016 Mar 21.

African Population and Health Research Center, Nairobi, Kenya.

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http://dx.doi.org/10.1123/jpah.2015-0510DOI Listing
August 2016
33 Reads
1 Citation

Can free open access resources strengthen knowledge-based emerging public health priorities, policies and programs in Africa?

F1000Research 2016, 5:853

F1000Research

Tackling emerging epidemics and infectious diseases burden in Africa requires increasing unrestricted open access and free use or reuse of regional and global policies reforms as well as timely communication capabilities and strategies. Promoting, scaling up data and information sharing between African researchers and international partners are of vital importance in accelerating open access at no cost. Free Open Access (FOA) health data and information acceptability, uptake tactics and sustainable mechanisms are urgently needed. These are critical in establishing real time and effective knowledge or evidence-based translation, proven and validated approaches, strategies and tools to strengthen and revamp health systems. As such, early and timely access to needed emerging public health information is meant to be instrumental and valuable for policy-makers, implementers, care providers, researchers, health-related institutions and stakeholders including populations when guiding health financing, and planning contextual programs.

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May 2016
2 Reads

Subcellular dissemination of prothymosin alpha at normal physiology: immunohistochemical vis-a-vis western blotting perspective.

BMC Physiol 2016 Mar 1;16. Epub 2016 Mar 1.

Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.

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http://dx.doi.org/10.1186/s12899-016-0021-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4774093PMC
March 2016
51 Reads

Interlinkage among cardio-metabolic disease markers in an urban poor setting in Nairobi, Kenya

Glob Health Action

Introduction The main cardio-metabolic diseases – mostly cardiovascular diseases such as stroke and ischemic heart disease – share common clinical markers such as raised blood pressure and blood glucose. The pathways of development of many of these conditions are also interlinked. In this regard, a higher level of co-occurrence of the main cardio-metabolic disease markers is expected. Evidence about the patterns of occurrence of cardio-metabolic markers and their interlinkage in the sub-Saharan African setting is inadequate. Objective The goal of the study was to describe the interlinkage among common cardio-metabolic disease markers in an African setting. Design We used data collected in a cross-sectional study from 5,190 study participants as part of cardiovascular disease risk assessment in the urban slums of Nairobi, Kenya. Five commonly used clinical markers of cardio-metabolic conditions were considered in this analysis. These markers were waist circumference, blood pressure, random blood glucose, total blood cholesterol, and triglyceride levels. Patterns of these markers were described using means, standard deviations, and proportions. The associations between the markers were determined using odds ratios. Results The weighted prevalence of central obesity, hypertension, hyperglycemia, hypercholesterolemia, and hypertriglyceridemia were 12.3%, 7.0%, 2.5%, 10.3%, and 17.3%, respectively. Women had a higher prevalence of central obesity and hypercholesterolemia as compared to men. Blood glucose was strongly associated with central obesity, blood pressure, and triglyceride levels, whereas the association between blood glucose and total blood cholesterol was not statistically significant. Conclusions This study shows that most of the common cardio-metabolic markers are interlinked, suggesting a higher probability of comorbidity due to cardio-metabolic conditions and thus the need for integrated approaches.

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February 2016
3 Reads

Analysis of Patterns of Physical Activity and Sedentary Behaviour in an Urban Slum Setting in Nairobi, Kenya

DOI: http://dx.doi.org/10.1123/jpah.2015-0510

Journal of Physical Activity and Health

Introduction: Insufficient physical activity and sedentary behaviour are key risk factors for the emergence of non-communicable diseases in sub-Saharan African setting. Given the limited evidence base, research is required to understand the trends. Objectives: To describe the patterns of physical activity and sedentary behaviour in a large sample of urban slum residents in Nairobi, Kenya. Methods: We used data collected from 5,190 study participants as part of cardio-vascular disease risk assessment. Data were collected about work, transport and recreation related physical activity besides sitting and sleeping time. Using time spent on each type of physical activity and respective Metabolic Equivalents, patterns of physical activity and associated factors were evaluated using descriptive statistics, Pearson correlations and logistic regression. Results: Nearly 50% of the study population were involved in work-related physical activities while only 6.3% in recreation-related. Involvement in physical activities decreased with age.17.4% had metabolic equivalent less than 600 METS-minutes per week. Higher sitting time was associated with insufficient physical activity. There were substantial gender differences in the time spent for physical activity. Conclusion: Given the positive relationship between insufficient physical activity and sedentary behaviour, complementary interventions that improve physical activity and at the same time reduce sitting time are needed. Key words: Physical activity, sitting time, recreation, metabolic equivalent

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February 2016
4 Reads

Evaluation of leishmanicidal activity and cytotoxicity of Ricinus communis and Azadirachta indica extracts from western Kenya: in vitro and in vivo assays.

BMC Res Notes 2015 Nov 5;8:650. Epub 2015 Nov 5.

Centre for Biotechnology Research and Development (CBRD), Kenya Medical Research Institute (KEMRI), P.O Box 54840-00200, Nairobi, Kenya.

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http://dx.doi.org/10.1186/s13104-015-1605-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4635543PMC
November 2015
20 Reads
3 Citations

Effects of Factory Labour Costs on Annual Returns to Tea Growers: A Case Study of KTDA Managed Factories in Kenya

Asian Journal of Agricultural Extension, Economics & Sociology, ISSN: 2320-7027,Vol.: 3, Issue.: 6 (

Asian Journal of Agricultural Extension, Economics & Sociology

The study sought to determine the effects of factory labour costs on annual returns to tea growers in Kenya. A case study design was adopted and data was collected through questionnaires. The research was conducted between September 2013 and March 2014. Descriptive and inferential statistics as well as multiple regression analysis was used to analyze the data. The study targeted a sample size of 89 respondents from which 74 was achieved. The sampling frame did consist of employees working in all departments and sections of the KTDA region 6 office and factories. The respondents were drawn from management, directors and external auditors of the 6 KTDA managed factories and stratified random sampling was applied. 52.5% of the respondents were male whereas 47.3% were female. 87.8% of the respondents had attained diploma and degree certificates while 87% of the respondents had served the organization for a period of ≥5 years. 97% of the respondents concurred with labour cost as the deciding factor of profitability. Regression results signpost to a variation of 56.50 on annual returns to tea growers was due to changes in factory labour costs. There was a strong positive relationship between factory labour costs and annual tea growers’ returns at 0.885. The study established that tea growers under KTDA are paid a monthly first payment; known as initial green leaf payment at a fixed rate of Kshs14 per kilogram of green leaf delivered to the factory but the second and annual return made after closure of financial period vary by factories depending on revenues received and costs incurred. Factory labour was identified in the study as one of the key factors that is negatively affecting annual returns to tea growers. Correspondingly, the collective bargaining agreements (CBA) negotiated by KTDA has led to above average seasonal labour payments.

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December 2014
3 Reads

F1 Cross-Breed Between Susceptible BALB/c and Resistant Swiss mice Infected with Leishmania major Exhibit an Intermediate Phenotype for Lesion Sizes and Type 1 Cytokines but Show Low Level of Total IgG Antibodies

DOI: 10.1111/sji.12159

Scandinavian Journal of Immunology © 2014 John Wiley & Sons Ltd

Our current understanding of the host immune response during leishmaniases largely derives from studies performed in mice due to the intrusive techniques required to study infected human patients. Swiss mice are highly resistant to Leishmania infections in concordance with observed response in humans, while BALB/c mice indicate a high-susceptibility phenotype. Developing a cross-breed between BALB/c and Swiss mice may have important consequences on disease development, immune responses and parasite killing, as yet, response of the cross-breed to Leishmania infection is superficial. The aim of the present study was to determine disease course and immune responses in F1 cross-breed between BALB/c and Swiss albino mice infected with L. major. Three mice groups were infected intradermally with stationary-phase L. major parasites with parental strains (BALB/c and Swiss albino) as controls. Lesion development was monitored weekly for 8 weeks and monocyte chemotactic protein (MCP-1), macrophage inflammatory protein (MIP-1α), interferon-gamma (IFN-γ) and IgG antibody quantified by enzyme-linked immunosorbent assay. The data were analysed using one-way analysis of variance and Tukey–Kramer test. Results indicated F1 mice having intermediate lesion sizes, type 1 cytokine levels and footpad parasite loads as compared to the parental strains. However, the F1 mice had low levels of IgG antibodies and parasite burden in the spleen. (P < 0.05). This study concludes that the F1 cross-breed between resistant and susceptible mice may be used as a requisite model to study the role of genetics in leishmaniases and perhaps other intracellular parasites.

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May 2014
2 Reads

Symptomatic malaria diagnosis overestimate malaria prevalence, but underestimate anaemia burdens in children: results of a follow up study in Kenya.

BMC Public Health 2014 Apr 9;14:332. Epub 2014 Apr 9.

School Natural Resources and Environmental Studies, Karatina University, P,O, Box 1957-10101, Karatina, Kenya.

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http://dx.doi.org/10.1186/1471-2458-14-332DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3996101PMC
April 2014
12 Reads
2 Citations
2.264 Impact Factor

Leishmaniases and schistosomiasis comorbidity potential in Kenya: the need for follow up studies

Afr J Health Sci. 2014; 27(1):30-45]

The African journal of Health Sciences

There are potential overlapping distributions of the protozoan parasite Leishmania and the parasitic helminth Schistosoma mansoni in eastern Africa most notably in endemic regions in the Sudan and Kenya. In murine model studies, the Th1-Th2 model of CD4+ T helper cell differentiation is a well-established paradigm for understanding the basis of protective versus pathogenic immune responses in the concomitance state that result in enhanced pathological changes and impaired parasite resolution. In complementation to the experimental studies, the concern for presages of human leishmaniases and schistosomiasis co-infections occurring is increased by their chronicity, displacement of people between endemic areas owing to conflict, climatic changes due to human activities, the spread through irrigation, pisciculture, water conservation schemes and human mobility in pursuit of economic dynamics and resources. Based on diseases prevalence, epidemiology and analyzing the associated risk factors undercurrents, several portents of comorbidity in Kenya are pinpointed. Taking into consideration the limited local resources and diminished surveillance of the areas affected by the two neglected tropical diseases, the discourse concludes that elimination of the diseases is still a challenge. There is need for pilot studies and/or elaborate field surveillance of concomitance and development strategies to mitigate the impending defy in Kenya and beyond.

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February 2014
92 Reads

Effectiveness of option B highly active antiretroviral therapy (HAART) prevention of mother-to-child transmission (PMTCT) in pregnant HIV women.

BMC Res Notes 2014 Jan 21;7:52. Epub 2014 Jan 21.

Tropical Pesticides Research Institute, Division of Livestock and Human Diseases Vector Control, Mosquito Section, Ngaramtoni, Off Nairobi road, PO Box 3024, Arusha, Tanzania.

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http://dx.doi.org/10.1186/1756-0500-7-52DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3898637PMC
January 2014
17 Reads
6 Citations

Safety of Prunus africana and Warburgia ugandensis in asthma treatment

Volume 88, September 2013, Pages 183–190

South African Journal of Botany

The aim of the study was to determine the possible cytotoxicity of the aqueous stem bark extracts of Prunus africana and Warburgia ugandensis to Vero E6 cells and acute toxicity in BALB/c mice. Despite being some of the most popular medicinal plants used in Africa, little is known about the safety. In-vitro cytotoxicity tests on Vero E6 cells were investigated using MTT assay to assess the safety of the two plant extracts. Vero E6 cells on growing to confluence were incubated with different drug concentrations for 48 h for the drug to take effect. Viability of the cells was measured by a scanning multiwell spectrophotometer, color intensity being equivalent to viable cells which reduce MTT to soluble formazan crystals. This was done by determining the CC50 of the extracts, CC50 being the concentration of the dose of the compound/extract that kills 50% of the cells. In acute toxicity a total of 55 mice were used. Mice were divided into eleven groups of 5 mice, one group served as negative control and ten groups received oral gavage doses at 500, 889.56, 1581.6, 2812.15 or 5000 mg/kg body weight once. Mortality and other signs of toxicity were recorded within 24 h and the weights of the surviving mice taken for 14 days thereafter. P. africana had CC50 of 104.08 μg/ml while W. ugandensis had CC50 > 250 μg/ml and both were classified as not cytotoxic. There was no mortality observed in groups of mice that received P. africana extracts at 500 and 889.56 mg/kg body weight. There was 20%, 60% and 100% mortality observed within 24 h for mice that received P. africana extracts at 1581.64, 2812.15 and 5000 mg/kg body weight respectively. Lethal dose (LD50) for P. africana was 2201.207 mg/kg body weight. W. ugandensis extracts had no mortality recorded in all dose levels and the LD50 was > 5000 mg/kg body weight. The weights of mice that survived the entire 14 days in all groups increased and were not significantly different from that of controls p > 0.05. From the in vitro and in vivo studies, the two extracts were safe to use. Though with their customary value among many Kenyan communities in management of asthma among other ailments there is a need for further validation of any anti-asthmatic properties and responsible chemical compounds to augment the findings.

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September 2013
3 Reads

Safety and Efficacy of Prunus africana and Warburgia ugandensis Against Induced Asthma in BALB/c Mice

European Journal of Medicinal Plants, ISSN: 2231-0894 ,Vol.: 3, Issue.: 3 (July-September)

European Journal of Medicinal Plants

Aim: In-Vitro and In-Vivo safety and anti-asthmatic activity of stem bark extracts of Prunus africana and Warburgia ugandensis against induced asthma in BALB/c mice. Methodology: Cytotoxicity on Vero E6 cells were investigated using MTT assay. Acute toxicity was determined by administering single oral gavages of extracts to five groups of BALB/c at 500, 889.56, 1581.64, 2812.15 and 5000mg/kg body weight doses. Efficacy against induced asthma was determined by assaying heart blood serum for ovalbumin specific immunoglobulin E (IgE) antibodies and quantification of eosinophil proportion in Bronchoalveolar lavage fluid (BALF). Eight sensitized groups were used, 2 were controls, 3 were treated with P. africana extract and 3 with W. ugandensis; each treatment group received one dose concentration of 125, 250 or 500mg/kg body weight of either plant extracts. Results: P. africana CC50 was 104.08µg/ml while W. ugandensis had CC50 > 250 µg/ml. In acute toxicity, mortality and signs of toxicity were recorded within 24 hours and the mice monitored for 14 days. There was 20%, 60% and 100% mortality within 24 hours for mice that received P. africana extracts at 1581.64, 2812.15 and 5000mg/kg body weight respectively. Lethal dose (LD50) for P. africana was 2201.207mg/kg body weight. W. ugandensis extracts had no mortality recorded and the LD50 was >5000mg/kg body weight. Treatment with P. africana extracts at 500mg/kg body weight reduced the IgE and BALF Eosinophil to 0.100±0.0001 and 2.80±0.20 respectively which were significantly different from positive controls P<0.05. W. ugandensis extracts at the same concentration reduced the IgE and BALF eosinophils to 0.134±0.00016 and 3.80±0.20 respectively and were significantly different from positive controls P<0.05. Conclusion: The results attested that P. africana and W. ugandensis stem bark extracts have anti-asthmatic property though there is need for further validation of anti-asthmatic chemical compounds to augment the findings. Keywords : Prunus africana; Warburgia ugandensis; cytotoxicity; vero cells; acute toxicity; lethal dose and efficacy.

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April 2013
3 Reads

Boosting Preparedness and Emergency Response Systems Capacity against Zika and Other Emerging Outbreaks in Low Resource and Vulnerable Settings

Austin J Infect Dis. 2016; 3(1): 1018

Austin J Infect Dis. 2016; 3(1): 1018

There is an urgent need to foster the development and establishment of robust and effective preparedness and emergency response systems capacity, and strengthening community-based programs and activities in improving Aedes-related Zika virus epidemics, mosquito’s larva breeding sites prevention and smart ecological management in vulnerable settings worldwide.

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4 Reads

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Body mass index and wealth index: positively correlated indicators of health and wealth inequalities in Nairobi slums

https://doi.org/10.1017/gheg.2018.10

Global Health, Epidemiology and Genomics

Introduction Wealth index is a known predictor of body mass index (BMI). Many studies have reported a positive association between BMI and socioeconomic status (SES). However, an in-depth investigation of the relationship between BMI and wealth index is lacking for urban slum settings. Objective To examine the association between BMI and wealth index in an urban slum setting in Nairobi, Kenya. Methods A total of 2003 adults between 40 and 60 years of age were included. BMI was derived from direct weight and height measurements. Wealth Index was computed using the standard principal component analysis of household amenities ownership. The relationship between BMI and wealth index was assessed using both linear and logistic regression models. Results We found that BMI linearly increased across the five quintiles of wealth index in both men and women, after adjusting for potential confounding factors. The prevalence of obesity increased from 10% in the first wealth quintile to 26.2% in the fifth wealth quintile. The average BMI for women entered the overweight category at the second quintile wealth status, or the third quintile for the total population. Conclusion There exists a strong positive relationship between BMI and wealth index in slum settings. Health promotion interventions aimed at reducing obesity may consider using wealth index in priority setting.

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