CIDRZ Research
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The CIDRZ Research Repository serves as an open-access archive for peer-reviewed publications, conference papers, and other scholarly outputs from CIDRZ researchers. Our goal is to promote the dissemination of knowledge and support evidence-based public health initiatives.
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Item Managing multiple funding streams and agendas to achieve local and global health and research objectives: lessons from the field.(2014-Jan-01) Holmes CB; Sikazwe I; Raelly RL; Freeman BL; Wambulawae I; Silwizya G; Topp SM; Chilengi R; Henostroza G; Kapambwe S; Simbeye D; Sibajene S; Chi H; Godfrey K; Chi B; Moore CB; *Centre for Infectious Disease Research in Zambia; †School of Medicine, University of North Carolina, Chapel Hill, NC; ‡School of Medicine, University of Alabama, Birmingham, AL; and §Division of Acquired Immunodeficiency Syndrome, National Institutes of Allergy and Infectious Diseases.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)Multiple funding sources provide research and program implementation organizations a broader base of funding and facilitate synergy, but also entail challenges that include varying stakeholder expectations, unaligned grant cycles, and highly variable reporting requirements. Strong governance and strategic planning are essential to ensure alignment of goals and agendas. Systems to track budgets and outputs, as well as procurement and human resources are required. A major goal of funders is to transition leadership and operations to local ownership. This article details successful approaches used by the newly independent nongovernmental organization, the Centre for Infectious Disease Research in Zambia.Item A mobile phone-based, community health worker program for referral, follow-up, and service outreach in rural Zambia: outcomes and overview.(2014-Aug) Schuttner L; Sindano N; Theis M; Zue C; Joseph J; Chilengi R; Chi BH; Stringer JS; Chintu N; 1 Centre for Infectious Disease Research in Zambia , Lusaka, Zambia .; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)BACKGROUND: Mobile health (m-health) utilizes widespread access to mobile phone technologies to expand health services. Community health workers (CHWs) provide first-level contact with health facilities; combining CHW efforts with m-health may be an avenue for improving primary care services. As part of a primary care improvement project, a pilot CHW program was developed using a mobile phone-based application for outreach, referral, and follow-up between the clinic and community in rural Zambia. MATERIALS AND METHODS: The program was implemented at six primary care sites. Computers were installed at clinics for data entry, and data were transmitted to central servers. In the field, using a mobile phone to send data and receive follow-up requests, CHWs conducted household health surveillance visits, referred individuals to clinic, and followed up clinic patients. RESULTS: From January to April 2011, 24 CHWs surveyed 6,197 households with 33,304 inhabitants. Of 15,539 clinic visits, 1,173 (8%) had a follow-up visit indicated and transmitted via a mobile phone to designated CHWs. CHWs performed one or more follow-ups on 74% (n=871) of active requests and obtained outcomes on 63% (n=741). From all community visits combined, CHWs referred 840 individuals to a clinic. CONCLUSIONS: CHWs completed all planned aspects of surveillance and outreach, demonstrating feasibility. Components of this pilot project may aid clinical care in rural settings and have potential for epidemiologic and health system applications. Thus, m-health has the potential to improve service outreach, guide activities, and facilitate data collection in Zambia.Item Lessons learnt from the first controlled human malaria infection study conducted in Nairobi, Kenya.(2015-Apr-28) Hodgson SH; Juma E; Salim A; Magiri C; Njenga D; Molyneux S; Njuguna P; Awuondo K; Lowe B; Billingsley PF; Cole AO; Ogwang C; Osier F; Chilengi R; Hoffman SL; Draper SJ; Ogutu B; Marsh K; Sanaria Inc, Rockville, MD, USA. pbillingsley@sanaria.com.; Sanaria Inc, Rockville, MD, USA. shoffman@sanaria.com.; Kenya Medical Research Institute - Wellcome Trust, Centre for Geographical Medical Research (Coast), Kilifi, Kenya. smolyneux@kemri-wellcome.org.; The Jenner Institute, University of Oxford, Oxford, UK. Susanne.hodgson@ndm.ox.ac.uk.; Centre for Research in Therapeutic Sciences, Strathmore University, Nairobi, Kenya. omandi.cole@gmail.com.; Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya. danielnjengah@yahoo.com.; Centre for Research in Therapeutic Sciences, Strathmore University, Nairobi, Kenya. eajuma@kemri.org.; Centre for Research in Therapeutic Sciences, Strathmore University, Nairobi, Kenya. bernhards.ogutu@indepth-network.org.; Kenya Medical Research Institute - Wellcome Trust, Centre for Geographical Medical Research (Coast), Kilifi, Kenya. asalim@kemri-wellcome.org.; Kenya Medical Research Institute - Wellcome Trust, Centre for Geographical Medical Research (Coast), Kilifi, Kenya. fosier@kemri-wellcome.org.; Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya. eajuma@kemri.org.; Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya. charles.magiri@usamru-k.org.; Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya. omandi.cole@gmail.com.; Kenya Medical Research Institute - Wellcome Trust, Centre for Geographical Medical Research (Coast), Kilifi, Kenya. patwnju@yahoo.co.uk.; Kenya Medical Research Institute - Wellcome Trust, Centre for Geographical Medical Research (Coast), Kilifi, Kenya. blowe@kemri-wellcome.org.; Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya. bernhards.ogutu@indepth-network.org.; The Jenner Institute, University of Oxford, Oxford, UK. simon.draper@ndm.ox.ac.uk.; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia. Roma.Chilengi@cidrz.org.; Kenya Medical Research Institute - Wellcome Trust, Centre for Geographical Medical Research (Coast), Kilifi, Kenya. kevin.marsh@ndm.ox.ac.uk.; Kenya Medical Research Institute - Wellcome Trust, Centre for Geographical Medical Research (Coast), Kilifi, Kenya. kawuondo@kemri-wellcome.org.; Kenya Medical Research Institute - Wellcome Trust, Centre for Geographical Medical Research (Coast), Kilifi, Kenya. COgwang@kemri-wellcome.org.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)BACKGROUND: Controlled human malaria infection (CHMI) studies, in which healthy volunteers are infected with Plasmodium falciparum to assess the efficacy of novel malaria vaccines and drugs, have become a vital tool to accelerate vaccine and drug development. CHMI studies provide a cost-effective and expeditious way to circumvent the use of large-scale field efficacy studies to deselect intervention candidates. However, to date few modern CHMI studies have been performed in malaria-endemic countries. METHODS: An open-label, randomized pilot CHMI study was conducted using aseptic, purified, cryopreserved, infectious P. falciparum sporozoites (SPZ) (Sanaria® PfSPZ Challenge) administered intramuscularly (IM) to healthy Kenyan adults (n = 28) with varying degrees of prior exposure to P. falciparum. The purpose of the study was to establish the PfSPZ Challenge CHMI model in a Kenyan setting with the aim of increasing the international capacity for efficacy testing of malaria vaccines and drugs, and allowing earlier assessment of efficacy in a population for which interventions are being developed. This was part of the EDCTP-funded capacity development of the CHMI platform in Africa. DISCUSSION: This paper discusses in detail lessons learnt from conducting the first CHMI study in Kenya. Issues pertinent to the African setting, including community sensitization, consent and recruitment are considered. Detailed reasoning regarding the study design (for example, dose and route of administration of PfSPZ Challenge, criteria for grouping volunteers according to prior exposure to malaria and duration of follow-up post CHMI) are given and changes other centres may want to consider for future studies are suggested. CONCLUSIONS: Performing CHMI studies in an African setting presents unique but surmountable challenges and offers great opportunity for acceleration of malaria vaccine and drug development. The reflections in this paper aim to aid other centres and partners intending to use the CHMI model in Africa.Item Rotavirus landscape in Africa-Towards prevention and control: A report of the 8th African rotavirus symposium, Livingstone, Zambia.(2015-Jun-26) Rudd C; Mwenda J; Chilengi R; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia. Electronic address: cheryl.rudd@cidrz.org.; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia.; WHO-Africa Regional Office, Brazzaville, Congo.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)The 8th African Rotavirus Symposium was held in Livingstone, Zambia from the 12-13 June 2014. Over 130 delegates from 35 countries - 28 from African nations - participated in this symposium, which included scientists, clinicians, immunisation managers, public health officials, policymakers and vaccine manufacturers. The theme for the symposium was Rotavirus Landscape in Africa-Towards Prevention and Control. At the time of the symposium, a total of 21 African countries had introduced the rotavirus vaccine into their national immunisation schedules. This meeting was particularly timely and relevant to review early data on vaccine adoption and impact from these countries. The concluding panel discussion proposed several recommendations for areas of focus moving forward in rotavirus advocacy and research.Item Pediatric HIV-HBV Coinfection in Lusaka, Zambia: Prevalence and Short-Term Treatment Outcomes.(2015-Dec) Peebles K; Nchimba L; Chilengi R; Bolton Moore C; Mubiana-Mbewe M; Vinikoor MJ; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.; Department of Pediatrics, University Teaching Hospital, Lusaka, Zambia.; Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA peebles.kathryn@gmail.com.; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)Hepatitis B virus (HBV) is endemic in Africa, where it may occur as an HIV coinfection. Data remain limited on HIV-HBV epidemiology in Africa, particularly in children. Using programmatic data from pediatric HIV clinics in Lusaka, Zambia during 2011-2014, we analyzed the prevalence of chronic HBV coinfection (defined as a single positive hepatitis B surface antigen [HBsAg] test) and its impact on immune recovery and liver enzyme elevation (LEE) during the first year of antiretroviral therapy. Among 411 children and adolescents, 10.4% (95% confidence interval, 7.6-14.1) had HIV-HBV. Coinfected patients were more likely to have World Health Organization stage 3/4, LEE and CD4 <14% at care entry (all p < 0.05). During treatment, CD4 increases and LEE incidence were similar by HBsAg status. HBsAg positivity decreased (11.8% vs. 6.6%; p = 0.24) following HBV vaccine introduction. These findings support screening pediatric HIV patients in Africa for HBV coinfection. Dedicated cohorts are needed to assess long-term outcomes of coinfection.Item Prevalence of hypertension and its treatment among adults presenting to primary health clinics in rural Zambia: analysis of an observational database.(2015-Sep-21) Yan LD; Chi BH; Sindano N; Bosomprah S; Stringer JS; Chilengi R; Department of Biostatistics, School of Public Health, University of Ghana, Accra, Ghana. samuel.bosomprah@cidrz.org.; Department of Obstetrics and Gynecology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA. jeffrey_stringer@med.unc.edu.; Primary Care and Health Systems Department, Center for Infectious Disease Research Zambia, Lusaka, Zambia. roma.chilengi@cidrz.org.; Primary Care and Health Systems Department, Center for Infectious Disease Research Zambia, Lusaka, Zambia. lilyyan@stanford.edu.; Primary Care and Health Systems Department, Center for Infectious Disease Research Zambia, Lusaka, Zambia. benjamin_chi@med.unc.edu.; Primary Care and Health Systems Department, Center for Infectious Disease Research Zambia, Lusaka, Zambia. samuel.bosomprah@cidrz.org.; Primary Care and Health Systems Department, Center for Infectious Disease Research Zambia, Lusaka, Zambia. ntazana.sindano@cidrz.org.; Department of Obstetrics and Gynecology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA. benjamin_chi@med.unc.edu.; Department of Obstetrics and Gynecology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA. roma.chilengi@cidrz.org.; Stanford University School of Medicine, Stanford, California, USA. lilyyan@stanford.edu.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)BACKGROUND: Hypertension constitutes a growing burden of illness in developing countries like Zambia. Adequately screening and treating hypertension could greatly reduce the complications of stroke and coronary disease. Our objective was to determine the prevalence of hypertension and identify current treatment practices among adult patients presenting for routine care to rural health facilities in the Better Health Outcomes through Mentoring and Assessments (BHOMA) project. METHODS: We conducted a retrospective analysis of routinely collected clinical data from 46 rural government clinics in Zambia. Our analysis cohort comprised patients ≥ 25 years with recorded blood pressure measurements, who sought care at primary health centers. Consistent with prior research, in our primary analysis, we only included data from first visits. Hypertension was defined as a systolic blood pressure ≥140 mmHg, or diastolic blood pressure ≥90 mmHg, or reported use of antihypertensive medication. A sensitivity analysis was performed using median blood pressure for individuals with multiple visits. RESULTS AND DISCUSSION: From January 2011 to December 2014, 116,130 first visits by adult patients met eligibility criteria. The crude prevalence of hypertension by onsite measurement or reported use of antihypertensive medication was 23.1% [95% CI: 22.8-23.3] (23.6% in females, 22.3% in males). The age standardized prevalence of hypertension across participating sites was 28.0 [95% CI: 27.7-28.3] (29.7% in females, 25.8% in males). Sensitivity analysis revealed a similar prevalence using data from all visits. Only 5.6% of patients had a diagnosis of hypertension documented in their medical record. Among patients with hypertension, only 18.0% had any antihypertensive drug prescribed, with nifedipine (8.9%), furosemide (8.3%), and propranolol (2.4%) as the most common. CONCLUSIONS: Age standardized prevalence of hypertension in rural primary health clinics in Zambia was high compared to other studies in rural Africa; however, we diagnosed hypertension with only one measurement and this may have biased our findings. Future efforts to improve hypertension control should focus on population preventive care and primary healthcare provider education on individual management.Item Health Promotion Through Existing Community Structures: A Case of Churches' Roles in Promoting Rotavirus Vaccination in Rural Zambia.(2016-Apr) Wesevich A; Chipungu J; Mwale M; Bosomprah S; Chilengi R; Centre for Infectious Disease Research in Zambia (CIDRZ), Lusaka, Zambia jenala.chipungu@cidrz.org.; Centre for Infectious Disease Research in Zambia (CIDRZ), Lusaka, Zambia.; Centre for Infectious Disease Research in Zambia (CIDRZ), Lusaka, Zambia Washington University in St. Louis, St. Louis, MO, USA.INTRODUCTION: Rural populations, particularly in Africa, suffer worse health outcomes from poor health services access. Community health workers (CHWs) effectively improve health outcomes, but the best means for CHWs reaching rural populations is unknown. Since Zambia is predominantly Christian, this study explored the use of CHWs through churches as an existing community structure for promoting preventive health behaviors, specifically rotavirus vaccine uptake. METHODS: A noncontrolled cross-sectional study of 32 churches receiving a packaged intervention of diarrhea prevention and treatment messaging was conducted with repeated time points of data collection over 13 months (2013-2014) in the Kafue District of Zambia. Two churches were selected for each of the 17 catchment areas, and CHWs were identified and trained in the intervention of promoting 4 key messages related to diarrhea prevention and treatment: hand washing with soap, exclusive breast-feeding, rotavirus vaccination, and treating diarrhea with oral rehydration solution and zinc. The intervention was conducted within existing church's women's groups, and data was collected on attendance and the distribution of Rota Cards for tracking rotavirus immunizations. RESULTS: Nineteen (59%) churches completed the study, and CHWs delivered health messages at a total of 890 women's group meetings. The overall reach of the intervention was to 37.0% of church-attending women, and the efficacy was 67.7% (317 of 468 Rota Cards collected at health centers). DISCUSSION: Implementing community health programs is often expensive and unsustainable, but the reach and efficacy levels achieved through existing structures like churches are encouraging in resource-constrained countries. Churches can be effective channels for delivering health prevention strategies to often difficult-to-reach rural populations. Further research is needed to investigate the impact of the intervention on health outcomes.Item Premature adult mortality in urban Zambia: a repeated population-based cross-sectional study.(2016-Mar-03) Rathod SD; Timæus IM; Banda R; Thankian K; Chilengi R; Banda A; Lemba M; Stringer JS; Chi BH; University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA.; Department of Population Studies, University of Zambia, Lusaka, Zambia.; Research, Publications and Dissemination Unit, Zambia Central Statistical Office, Lusaka, Zambia.; Department of Population Health, London School of Hygiene and Tropical Medicine, London, UK.; Department of Gender Studies, University of Zambia, Lusaka, Zambia.; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia.; Department of Population Health, London School of Hygiene and Tropical Medicine, London, UK Centre for Actuarial Research, University of Cape Town, Cape Town, South Africa.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)OBJECTIVES: To measure the sex-specific and community-specific mortality rates for adults in Lusaka, Zambia, and to identify potential individual-level, household-level and community-level correlates of premature mortality. We conducted 12 survey rounds of a population-based cross-sectional study between 2004 and 2011, and collected data via a structured interview with a household head. SETTING: Households in Lusaka District, Zambia, 2004-2011. PARTICIPANTS: 43,064 household heads (88% female) who enumerated 123,807 adult household members aged between 15 and 60 years. PRIMARY OUTCOME: Premature adult mortality. RESULTS: The overall mortality rate was 16.2/1000 person-years for men and 12.3/1000 person-years for women. The conditional probability of dying between age 15 and 60 (45q15) was 0.626 for men and 0.537 for women. The top three causes of death for men and women were infectious in origin (ie, tuberculosis, HIV and malaria). We observed an over twofold variation of mortality rates between communities. The mortality rate was 1.98 times higher (95% CI 1.57 to 2.51) in households where a family member required nursing care, 1.44 times higher (95% CI 1.22 to 1.71) during the cool dry season, and 1.28 times higher (95% CI 1.06 to 1.54) in communities with low-cost housing. CONCLUSIONS: To meet Zambia's development goals, further investigation is needed into the factors associated with adult mortality. Mortality can potentially be reduced through focus on high-need households and communities, and improved infectious disease prevention and treatment services.Item Association of Maternal Immunity with Rotavirus Vaccine Immunogenicity in Zambian Infants.(2016) Chilengi R; Simuyandi M; Beach L; Mwila K; Becker-Dreps S; Emperador DM; Velasquez DE; Bosomprah S; Jiang B; University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia.; Centres for Disease Control and Prevention, Atlanta, Georgia, United States of America.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)INTRODUCTION: Live attenuated oral vaccines against rotavirus (RV) have been shown to be less efficacious in children from developing countries. Reasons for this disparity are not fully understood. We assessed the role of maternal factors including breast milk RV-specific IgA, transplacentally acquired infant serum RV-specific IgG and maternal HIV status in seroconversion among Zambian infants routinely immunized with Rotarix™ (RV1). METHODS: 420 mother-child pairs were recruited at infant age 6-12 weeks in Lusaka. Clinical information and samples were collected at baseline and at one month following the second dose of RV1. Determination of breast milk RV-specific IgA and serum RV-specific IgA and IgG was done using standardized ELISA. Seroconversion was defined as a ≥ 4 fold rise in serum IgA titre from baseline to one-month post RV1 dose 2, while seropositivity of IgA was defined as serum titre ≥ 40 and antibody variables were modelled on log-base 2. Logistic regression was used to identify predictors of the odds of seroconversion. RESULTS: Baseline infant seropositivity was 25.5% (91/357). The seroconversion frequency was 60.2% (130/216). Infants who were IgA seropositive at baseline were less likely to seroconvert compared to their seronegative counterparts (P = 0.04). There was no evidence of an association between maternal HIV status and seroconversion (P = 0.25). Higher titres of breast milk rotavirus-specific IgA were associated with a lower frequency of seroconverson (Nonparametric test for trend Z = -2.84; P<0.01): a two-fold increase in breast milk RV-specific IgA titres was associated with a 22% lower odds of seroconversion (OR = 0.80; 95% CI = 0.68-0.94; P = 0.01). There was seasonal variation in baseline breast milk rotavirus-specific IgA titres, with significantly higher GMTs during the cold dry months (P = 0.01). CONCLUSION: Low immunogenicity of RV1 vaccine could be explained in part by exposure to high antibody titres in breast milk and early exposure to wild-type rotavirus infections. Potential interference of anti-RV specific IgA in breast milk and pre-vaccination serum RV specific-IgA and IgG titres with RV1 seroconversion and effectiveness requires further research.Item A Preliminary Assessment of Rotavirus Vaccine Effectiveness in Zambia.(2016-May-01) Beres LK; Tate JE; Njobvu L; Chibwe B; Rudd C; Guffey MB; Stringer JS; Parashar UD; Chilengi R; Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.; Centre for Infectious Disease Research in Zambia, Lusaka Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.; Centre for Infectious Disease Research in Zambia, Lusaka.; University of North Carolina School of Medicine, Chapel Hill.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)BACKGROUND: Diarrhea is the third leading cause of child death in Zambia. Up to one-third of diarrhea cases resulting in hospitalization and/or death are caused by vaccine-preventable rotavirus. In January 2012, Zambia initiated a pilot introduction of the Rotarix live, oral rotavirus vaccine in all public health facilities in Lusaka Province. METHODS: Between July 2012 and October 2013, we conducted a case-control study at 6 public sector sites to estimate rotavirus vaccine effectiveness (VE) in age-eligible children presenting with diarrhea. We computed the odds of having received at least 1 dose of Rotarix among children whose stool was positive for rotavirus antigen (cases) and children whose stool was negative (controls). We adjusted the resulting odds ratio (OR) for patient age, calendar month of presentation, and clinical site, and expressed VE as (1 - adjusted OR) × 100. RESULTS: A total of 91 rotavirus-positive cases and 298 rotavirus-negative controls who had under-5 card-confirmed vaccination status and were ≥6 months of age were included in the case-control analysis. Among rotavirus-positive children who were age-eligible to be vaccinated, 20% were hospitalized. Against rotavirus diarrhea of all severity, the adjusted 2-dose VE was 26% (95% confidence interval [CI], -30% to 58%) among children ≥6 months of age. VE against hospitalized children ≥6 months of age was 56% (95% CI, -34% to 86%). CONCLUSIONS: We observed a higher point estimate for VE against increased severity of illness compared with milder disease, but were not powered to detect a low level of VE against milder disease.