Use of modified respondent driven sampling methodology to enhance identification and recruitment of most at risk persons into an HIV prevention trial in Kisumu, Western Kenya

Philosophiae Doctor - PhDThis thesis presents research on the use of modified respondent driven sampling (mRDS) methodology to enhance identification and recruitment of key populations (KP) into an HIV prevention trial in Kisumu, western Kenya through a three phase mixed method study. The study was carried out in Kisumu, western Kenya within the Kenya Medical Research Institute (KEMRI) and the US Centers for Disease Control and Prevention (CDC) Research and Public Health Collaboration platform. The three phases included: 1. PHASE I: Identification and determination of categories of KPs and techniques of locating and motivating them to participate in HIV prevention trials.2. PHASE II: Design and Implementation of a mRDS methodology in recruiting Ks into HIV prevention trials.3. PHASE III: Evaluation of the mRDS in recruitment of KPs into an HIV incidence cohort study. Methods Phase I of the study included the conduct of in depth interviews which were used to identify different categories of persons considered to be KPs within Kisumu, identify strategies of locating the KPs and determine motivators and inhibitors of KPs participation in HIV prevention trials. Phase II on the other hand included the administration of a survey that had been refined in Phase I. The survey was used to design a mRDS methodology which was then implemented to recruit KPs into the survey. Phase III evaluated the success of the mRDS in recruiting KPs into an HIV prevention study by assessing the risk profiles for participants screened and enrolled into the Phase III study. Ethical approval for the study was sought from the ethics committee of the Kenya Medical Research Institute, the US CDC and the University of the Western Cape.The study recruited 53 individuals into phase I and was able to 8 identify different categories of people considered to be KPs and the 4 salient strategies that could be used to recruit them into HIV prevention studies. The phase also identified 8 potential motivators and 9 potential inhibitors to participation in HIV prevention research. These categories and salient strategies were used in phase II to develop and pilot a mRDS methodology in recruiting 203 individuals into a survey. The survey was used as a validation tool for the risk levels of persons recruited by the mRDS using the variables of inconsistent condom use and having multiple partners. The validated mRDS was then applied in the recruitment of 1,292 participants in phase III of thestudy. These study participants had characteristics similar to those seen in similar studies and elucidated from phases I and II of the study. HIV seropositivity was used as the variable for validating risk levels of participants in this study and this was found to be higher that that seen in general population and comparable to that seen in other KPs groups in the region. Results: Overall the study was able to identify different categories of people considered to be at high riskof HIV acquisition. The groups identified included people who frequent bars (e.g. bar workers, drunkards, sex workers, businessmen), people who work in transportation (e.g. truck drivers, matatu drivers, motorcycle drivers, taxi drivers, bicycle taxi drivers), fishermen/fishmongers, MSM and hair salon workers. The study also identified using personal contact, link persons, peer mobilisers and leaders as strategies of identifying and locating KPs. The study used the mRDS successfully in recruiting participants with evaluation of inconsistent condom use and multiple sexual partnerships showing the participants to be of high risk behaviour. Of all the females in the study, only 3.3% were pregnant. The prevalence of Chlamydia was 2.9%, gonorrhoea was 5.0%, syphilis was 0.4% and HSV-2 was 46.0%. Those who tested positive for HIV were 26.2% with 42.3% of the HIV positive participants having CD4 counts of between 250 – 500 cells/ml. Recommendations and Conclusion:The mRDS was successful in recruiting KPs in an HIV prevention trial. Majority of the participants reported inconsistent condom use and having multiple sex partners. In addition to MSM, SW and transport industry workers, fisherfolk, discordant couples, widowers, street youth, car washers and police also form part of KPs groups. The HIV prevalence was higher amongst these groups compared to general population with discordant couples having the highest HIV prevalence. The study recommends that mRDS should be used to identify and recruit KPs as it not only allows for faster recruitment of KPs, it also reduces the expense and complexity associated with coupon management in the standard RDS

Prevalence and quality of syndromic diagnosis of sexually transmitted infections within the Kisumu incidence cohort study in Kisumu, Kenya

Magister Public Health - MPHBackground: STIs are of major public health concern in developing countries, not least because they facilitate transmission of HIV, but also because they are important causes of mortality and morbidity among African populations, resulting in, among other things, adverse birth outcomes, neonatal and infant infections, ectopic pregnancy, anogenital cancer,infertility, pelvic inflammatory disease, and death. Thus, effective treatment needs to be prompt and accurate to control the spread, and morbidity and mortality of STIs. Even though syndromic approach to the management of STIs is effective, most evaluations have focused on syndromic STI management within STI clinics as opposed to research studies. Partner notification is an integral component of the syndromic approach and is aimed at preventing onward transmission of infection as well as re-infection. It includes informing sexual partners of infected people of their exposure, administering presumptive treatment, and providing advice about the prevention of future infection.Methods: This is a cross sectional descriptive study based on a retrospective review of STI data of study participants in KICoS aged 18 to 34 years. A non probability convenience sampling method was used to recruit study participants. A total of 1,277 participants were prescreened into KICoS of whom 847 were enrolled into this study. Data was collected using CAPI and ACASI questionnaires as well as Teleforms which was analysed in SAS for windows 9.1. Results: Syndromic prevalence of STIs was 5.7% while the aetiological prevalence was 32.8%.Risk factors to STI acquisition included, being female, having multiple sexual partners,having lower than tertiary education, using recreational drugs and being HIV. Agreement between the interviewing methods as well between the syndromic and laboratory diagnosis ranged from fair to substantial. This was also true for the agreement between laboratory and CAPI as well as between the laboratory and ACASI. Sensitivity was generally low while specificity was high. Uptake of contact tracing cards was high though with very low uptake of contact treatment with only 2.1% and 0.4% partners of the syndromically and aetiologically diagnosed participants coming for treatment.Conclusions: STI is a problem in this community and thus there should be more emphasis on risk reduction messages in patient education to mitigate the spread of STIs. The performance of syndromic management was very poor against the aetiological diagnosis thus there needs to further review the use of syndromic diagnosis of STIs in research settings. Partner tracing needs to be intensified since there was very poor partner treatment even with high uptake of contact cards.Acknowledgements: This study would have not been what it was without the immense support I received from many individuals all of whom cannot be mentioned here. I would however want to thank the Dr Wairimu Chege (Principal Investigator, KICoS) for her inspiration and encouragement. I would also like to thank my supervisor, Ernie Kunneke for going through this study with me repeated times including on a ride to the airport. On the same note I would also like to thank my lecturers and student administrators at the SOPH. My gratitude also goes to my colleagues Richard Ndivo, Sherri Pals and Eleanor McLellan-Lemal for all the support they accorded me throughout this research.I would also want to give my heartfelt gratitude to my family. My daughter Akinyi who used to type with me at night, her mother Auma for understanding my late nights up and finally to my Parents Mr and Mrs Gideon and Monica Otieno for understanding the importance of education and taking me to school through all the difficulties. Last but not least I would like to express my gratitude to the almighty God for having seen me through this process

SEMI-STOCHASTIC MIXTURE MODEL FOR PREDICTING THE RATE OF ROAD CARNAGES IN KENYA

In this paper we consider the problem of modeling and predicting the rate of road carnage in Kenya inthe presence of randomly changing road conditions. In the literature review, accident prediction ratemodels are typically regression models and discrete time series models. We study such models andexamine their strengths and weaknesses and propose a Semi-stochastic Mixture Model to describethe relation between the highway accidents and the road environment dynamics.The aim of theresearch paper is to propose a model that captures both the deterministic and stochastic nature ofroad parameters to explain the cause of high rate of road accidents in Kenya. We apply the proposedmodel to a simulated data set for the local condition. Our analysis from show that apart from annualaverage daily traffic (AADT), road curvature is an important component of road carnage.Keywords: Road system, Semi-stochastic mixture model, road curvature, road carnage,Simulation

Application of Queuing Theory to Vehicular Traffic on Nakuru Total Road Stretch

 Nations strive to avoid losing revenue and human lives through long traffic snarl ups and frequent accidents on the roads. For this reason Considerations must be made to increase the number of lanes or even better to change from a single carriage to more robust dual carriages. However number of lanes and dual carriage alone serve no purpose for the accidents frequencies and traffic snarl ups that appear to defy even the most modern and sophisticated highway designs. Service time for traffic using such roads would need to be improved. Clearly therefore a numerical model is necessary for the road designers and developers to help understand road improvement demands. In this paper we establish the queue model for the Nakuru – Salgaa road Stretch and test the model with real data from the Case Study. Data is collected between the Soil- junction and the Total junction. We derive the arrival rate, service rate, utilization rate and the probability of Bulking using the M/M/1 queuing model. It is estimated that the arrival rate at the Soil- junction is 37 vehicles per minute and at total junction the service rate is 44 Vehicles per minute this does not march the dwindle service rates in section that are now black spots. The average number of vehicles on single road stretch is on average 15 per minute with some sections recording a high of 40 vehicles per minute and the utilization of the sections of stretch is on average 0.8. The benefit of performing the queue analysis for the road stretch is finally discussed and recommendations provided. 

Association of Partner Support and Partner Communication with Provider Prescribed Contraceptive Method Use among Heterosexual Couples in Kisumu, Kenya

We explored partner support and communication factors associated with provider prescribed contraceptive (PPC) use to inform contraception  interventions among heterosexual couples in Kenya. From April 2014 through September 2016, 252 community recruited couples in Kisumu, Kenya, were enrolled. Men and women were surveyed separately and asked about communication regarding sexual/reproductive health and relationship characteristics. PPC use was defined as female reported use of pills, injection, implant, IUD, or tubal ligation. Multivariable Poisson regression with robust variance estimate was used to identify factors associated with PPC. In multivariable modeling, women who reported discussing the future of their relationship with their partner were 2.46 (95% CI: 1.13-5.36) times more likely, and men who reported discussing condom use were 0.83 (95% CI: 0.72-0.95) time less likely, to report PPC use. These findings call for greater attention to involving male partners, incorporating communication skills, and relationship characteristics into interventions in our and similar settings.  Keywords: Family planning, male involvement, reproductive health, agency, Africa Nous avons exploré le soutien des partenaires et les facteurs de communication associés à l'utilisation de contraceptifs prescrits par le fournisseur (PPC) pour informer les interventions de contraception auprès des couples hétérosexuels au Kenya. D'avril 2014 à septembre 2016, 252 couples recrutés par la communauté à Kisumu, au Kenya, étaient inscrits. Les hommes et les femmes ont été interrogés séparément et interrogés sur la communication concernant la santé sexuelle / reproductive et les caractéristiques des relations. L'utilisation du CPP a été définie comme l'utilisation déclarée par les femmes de pilules, d'injection, d'implant, de DIU ou de ligature des trompes. Une régression de Poisson multivariable avec une estimation de variance robuste a été utilisée pour identifier les facteurs associés au CPP. Dans la modélisation multivariable, les femmes qui ont déclaré discuter de l'avenir de leur relation avec leur partenaire étaient 2,46 (IC à 95%: 1,13-5,36) fois plus susceptibles, et les hommes qui ont  déclaré discuter de l'utilisation du préservatif étaient 0,83 (IC à 95%: 0,72-0,95). Moins susceptibles de signaler l'utilisation du PPC. Ces résultats appellent à une plus grande attention à l'implication des partenaires masculins, à l'intégration des compétences en communication et des caractéristiques relationnelles dans les interventions dans notre environnement et dans des environnements similaires. Mots-clés: Planification familiale, implication masculine, santé reproductive, agence, Afriqu

Identifying gaps in HIV policy and practice along the HIV care continuum: evidence from a national policy review and health facility surveys in urban and rural Kenya.

The last decade has seen rapid evolution in guidance from the WHO concerning the provision of HIV services along the diagnosis-to-treatment continuum, but the extent to which these recommendations are adopted as national policies in Kenya, and subsequently implemented in health facilities, is not well understood. Identifying gaps in policy coverage and implementation is important for highlighting areas for improving service delivery, leading to better health outcomes. We compared WHO guidance with national policies for HIV testing and counselling, prevention of mother-to-child transmission, HIV treatment and retention in care. We then investigated implementation of these national policies in health facilities in one rural (Kisumu) and one urban (Nairobi) sites in Kenya. Implementation was documented using structured questionnaires that were administered to in-charge staff at 10 health facilities in Nairobi and 34 in Kisumu. Policies were defined as widely implemented if they were reported to occur in?>?70% facilities, partially implemented if reported to occur in 30-70% facilities, and having limited implementation if reported to occur in?<?30% facilities. Overall, Kenyan national HIV care and treatment policies were well aligned with WHO guidance. Policies promoting access to treatment and retention in care were widely implemented, but there was partial or limited implementation of several policies promoting access to HIV testing, and the more recent policy of Option B+ for HIV-positive pregnant women. Efforts are needed to improve implementation of policies designed to increase rates of diagnosis, thus facilitating entry into HIV care, if morbidity and mortality burdens are to be further reduced in Kenya, and as the country moves towards universal access to antiretroviral therapy

Performance of a rapid antigen test for SARS-CoV-2 in Kenya

Testing for SARS-CoV-2 in resource-poor settings remains a considerable challenge. Gold standard nucleic acid tests are expensive and depend on availability of expensive equipment and highly trained laboratory staff. More affordable and easier rapid antigen tests are an attractive alternative. This study assessed field performance of such a test in western Kenya. We conducted a prospective multi-facility field evaluation study of NowCheck COVID-19 Ag-RDT compared to gold standard PCR. Two pairs of oropharyngeal and nasopharyngeal swabs were collected for comparative analysis. With 997 enrolled participants the Ag-RDT had a sensitivity 71.5% (63.2-78.6) and specificity of 97.5% (96.2-98.5) at cycle threshold value <40. Highest sensitivity of 87.7% (77.2-94.5) was observed in samples with cycle threshold values ≤30. NowCheck COVID-19 Ag-RDT performed well at multiple healthcare facilities in an African field setting. Operational specificity and sensitivity were close to WHO-recommended thresholds

The effect of agricultural trade openness on economic growth in the East African Community

AbstractThe study examined the effects of agricultural trade openness on economic growth in the EAC. We empirically analyzed the issue in five countries from 2000 to 2021. Panel data estimation methods were used in the study. The variables were found to be integrated of order one and zero. There was presence of cointegration, cross-sectional heterogeneity and cross-sectional dependence. The CS-ARDL results revealed that agricultural trade openness and economic growth enjoyed a long-run relationship. The empirical results indicated that the effect of agricultural trade openness on economic growth was positive and significant in the long run. Bootstrap panel granger causality analysis was applied in testing the nature and direction of causal relationships between variables. The results indicated that a unidirectional causal relationship existed between agricultural trade openness and economic growth. This implies that an increase in trade openness promotes economic growth. Based on the findings of the study, we recommend that strategies aimed at promoting trade openness should be complemented with strong policies to enable EAC countries to reap more growth benefits associated with open trade

Prevalence, incidence and correlates of HSV-2 infection in an HIV incidence adolescent and adult cohort study in western Kenya.

Herpes simplex virus type 2 (HSV-2) infections are associated with increased risk of HIV transmission. We determined HSV-2 prevalence, incidence and associated risk factors, incidence among persons with indeterminate results, and prevalence of HSV-2/HIV co-infection among young adults (18-34 years) and adolescents (16-17 years) enrolled in an HIV incidence cohort study in western Kenya.Participants (n = 1106; 846 adults) were screened and those HIV-1 negative were enrolled and followed-up quarterly for one year. HSV-2 was assessed using the Kalon enzyme immunoassay. HSV-2 incidence was calculated separately among HSV-2 seronegative participants and those indeterminate at baseline. Logistic regression was used to estimate the odds of HSV-2 infection and Poisson regression was used to assess HSV-2 incidence and associated factors.Overall, HSV-2 prevalence was 26.6% [95% confidence interval (CI): 23.9-29.4] and was higher in adults (31.5% [95% CI: 28.3-34.9]) than adolescents (10.7% [95% CI: 7.1-15.3]). Factors associated with prevalent HSV-2 included female gender, increasing age, HIV infection, history of sexually transmitted infection, low level of education, multiple sexual partners, and being married, divorced, separated or widowed. Overall HSV-2 incidence was 4.0 per 100 person-years (/100PY) 95% CI: 2.7-6.1 and was higher in adults (4.5/100PY) and females (5.1/100PY). In multivariable analysis only marital status was associated with HSV-2 incidence. Among 45 participants with indeterminate HSV-2 results at baseline, 22 seroconverted, resulting in an incidence rate of 53.2 /100PY [95% CI: 35.1-80.9]. Inclusion of indeterminate results almost doubled the overall incidence rate to 7.8 /100 PY [95% CI: 5.9-10.5]. Prevalence of HIV/HSV-2 co-infection was higher in female adults than female adolescents (17.1 [95% CI: 13.6-21.0] versus 3.4 [95% CI: 1.1-7.8]).The high incidence rate among persons with indeterminate results underscores the public health concerns for HSV-2 spread and underreporting of the HSV-2 burden. Careful consideration is needed when interpreting HSV-2 serology results in these settings

Adult hematological and biochemistry reference values (median and 95^th-percentile) comparison between locally-established reference intervals versus reference values from the Kisumu Incidence cohort study in western Kenya (2007–2010).

<p>Adult hematological and biochemistry reference values (median and 95^th-percentile) comparison between locally-established reference intervals versus reference values from the Kisumu Incidence cohort study in western Kenya (2007–2010).</p