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Laksanasopin T.,Columbia University | Guo T.W.,Columbia University | Nayak S.,Columbia University | Sridhara A.A.,Columbia University | And 15 more authors.
Science Translational Medicine | Year: 2015

This work demonstrates that a full laboratory-quality immunoassay can be run on a smartphone accessory. This low-cost dongle replicates all mechanical, optical, and electronic functions of a laboratory-based enzyme-linked immunosorbent assay (ELISA) without requiring any stored energy; all necessary power is drawn from a smartphone. Rwandan health care workers used the dongle to test whole blood obtained via fingerprick from 96 patients enrolling into care at prevention of mother-to-child transmission clinics or voluntary counseling and testing centers. The dongle performed a triplexed immunoassay not currently available in a single test format: HIV antibody, treponemal-specific antibody for syphilis, and nontreponemal antibody for active syphilis infection. In a blinded experiment, health care workers obtained diagnostic results in 15 min from our triplex test that rivaled the gold standard of laboratory-based HIV ELISA and rapid plasma reagin (a screening test for syphilis), with sensitivity of 92 to 100% and specificity of 79 to 100%, consistent with needs of current clinical algorithms. Patient preference for the dongle was 97% compared to laboratory-based tests, with most pointing to the convenience of obtaining quick results with a single fingerprick. This work suggests that coupling microfluidics with recent advances in consumer electronics can make certain laboratory-based diagnostics accessible to almost any population with access to smartphones.


PubMed | Centers for Disease Control and Prevention, Institute of HIV Disease Prevention and Control, OPKO Diagnostics LLC and Columbia University
Type: Journal Article | Journal: Science translational medicine | Year: 2015

This work demonstrates that a full laboratory-quality immunoassay can be run on a smartphone accessory. This low-cost dongle replicates all mechanical, optical, and electronic functions of a laboratory-based enzyme-linked immunosorbent assay (ELISA) without requiring any stored energy; all necessary power is drawn from a smartphone. Rwandan health care workers used the dongle to test whole blood obtained via fingerprick from 96 patients enrolling into care at prevention of mother-to-child transmission clinics or voluntary counseling and testing centers. The dongle performed a triplexed immunoassay not currently available in a single test format: HIV antibody, treponemal-specific antibody for syphilis, and nontreponemal antibody for active syphilis infection. In a blinded experiment, health care workers obtained diagnostic results in 15 min from our triplex test that rivaled the gold standard of laboratory-based HIV ELISA and rapid plasma reagin (a screening test for syphilis), with sensitivity of 92 to 100% and specificity of 79 to 100%, consistent with needs of current clinical algorithms. Patient preference for the dongle was 97% compared to laboratory-based tests, with most pointing to the convenience of obtaining quick results with a single fingerprick. This work suggests that coupling microfluidics with recent advances in consumer electronics can make certain laboratory-based diagnostics accessible to almost any population with access to smartphones.


Nsanzimana S.,Institute of HIV Disease Prevention and Control | Nsanzimana S.,Swiss Tropical and Public Health Institute | Kanters S.,Global Evaluative science | Kanters S.,University of British Columbia | And 8 more authors.
The Lancet HIV | Year: 2015

BACKGROUND: Rwanda has made remarkable progress towards HIV care programme with strong national monitoring and surveillance. Knowledge about the HIV care continuum model can help to improve outcomes in patients. We aimed to quantify engagement, mortality, and loss to follow-up of patients along the HIV care continuum in Rwanda in 2013. METHODS: We collated data for individuals with HIV who participated in the national HIV care programme in Rwanda and calculated the numbers of individuals or proportions of the population at each stage and the transition probabilities between stages of the continuum. We calculated factors associated with mortality and loss to follow-up by fitting Cox proportional hazards regression models, one for the stage of care before antiretroviral therapy (ART) initiation and another for stage of care during ART. FINDINGS: An estimated 204 899 individuals were HIV-positive in Rwanda in 2013. Among these individuals, 176 174 (86%) were in pre-ART or in ART stages and 129 405 (63%) had initiated ART by the end of 2013. 82·1% (95% CI 80·7-83·4) of patients with viral load measurements (n=3066) were virally suppressed (translating to 106 371 individuals or 52% of HIV-positive individuals). Mortality was 0·6% (304 patients) in the pre-ART stage and 1·0% (1255 patients) in the ART stage; 2247 (3·9%) patients were lost to follow-up in pre-ART stage and 2847 (2·2%) lost in ART stage. Risk factors for mortality among patients in both pre-ART and ART stages included older age, CD4 cell count at initiation, and male sex. Risk factors for loss to follow-up among patients at both pre-ART and ART stages included younger age (age 10-29 year) and male sex. s: The HIV care continuum is a multitrajectory pathway in which patients have many opportunities to leave and re-engage in care. Knowledge about the points at which individuals are most likely to leave care could improve large-scale delivery of HIV programmes. FUNDING: The Bill & Melinda Gates Foundation. © 2015 Elsevier Ltd. All rights reserved.


Kayigamba F.R.,INTERACT | Bakker M.I.,Royal Tropical Institute | Fikse H.,Royal Tropical Institute | Mugisha V.,University of Kigali | And 4 more authors.
PLoS ONE | Year: 2012

Introduction: Access to antiretroviral therapy (ART) has increased greatly in sub-Saharan Africa. However many patients do not enrol timely into HIV care and treatment after HIV diagnosis. We studied enrolment into care and treatment and determinants of non-enrolment in Rwanda. Methods: Data were obtained from routine clinic registers from eight health facilities in Rwanda on patients who were diagnosed with HIV at the antenatal care, voluntary counselling-and-testing, outpatient or tuberculosis departments between March and May 2009. The proportion of patients enrolled into HIV care and treatment was calculated as the number of HIV infected patients registered in ART clinics for follow-up care and treatment within 90 days of HIV diagnosis divided by the total number of persons diagnosed with HIV in the study period. Results: Out of 482 patients diagnosed with HIV in the study period, 339 (70%) were females, and the median age was 29 years (interquartile range [IQR] 24-37). 201 (42%) enrolled into care and treatment within 90 days of HIV diagnosis. The median time between testing and enrolment was six days (IQR 2-14). Enrolment in care and treatment was not significantly associated with age, sex, or department of testing, but was associated with study site. None of those enrolled were in WHO stage 4. The median CD4 cell count among adult patients was 387 cells/mm3 (IQR: 242-533 cells/mm3); 81 of 170 adult patients (48%) were eligible to start ART (CD4 count<350 cells/mm3 or WHO stage 4). Among those eligible, 45 (56%) started treatment within 90 days of HIV diagnosis. Conclusion: Less than 50% of diagnosed HIV patients from eight Rwandan health facilities had enrolled into care and treatment within 90 days of diagnosis. Improving linkage to care and treatment after HIV diagnosis is needed to harness the full potential of ART. © 2012 Kayigamba et al.


Nsanzimana S.,Institute of HIV Disease Prevention and Control | Remera E.,Institute of HIV Disease Prevention and Control | Kanters S.,Global Evaluative science | Kanters S.,University of British Columbia | And 9 more authors.
The Lancet Global Health | Year: 2015

Background: Rwanda has achieved substantial progress in scaling up of antiretroviral therapy. We aimed to assess the effect of increased access to antiretroviral therapy on life expectancy among HIV-positive patients in two distinct periods of lower and higher antiretroviral therapy coverage (1997-2007 and 2008-11). Methods: In a retrospective observational cohort study, we collected clinical and demographic data for all HIV-positive patients enrolled in care at 110 health facilities across all five provinces of Rwanda. We included patients aged 15 years or older with a known enrolment date between 1997 and 2014. We constructed abridged life tables from age-specific mortality rates and life expectancy stratified by sex, CD4 cell count, and WHO disease stage at enrolment in care and initiation of antiretroviral therapy. Findings: We included 72 061 patients in this study, contributing 213 983 person-years of follow-up. The crude mortality rate was 33·4 deaths per 1000 person-years (95% CI 32·7-34·2). Life expectancy for the overall cohort was 25·6 additional years (95% CI 25·1-26·1) at 20 years of age and 23·3 additional years (95% CI 22·9-23·7) at 35 years of age. Life expectancy at 20 years of age in the period of 1997-2007 was 20·4 additional years (95% CI 19·5-21·3); for the period of 2008-11, life expectancy had increased to 25·6 additional years (95% CI 24·8-26·4). Individuals enrolling in care with CD4 cell counts of 500 cells per μL or more, and with WHO disease stage I, had the highest life expectancies. Interpretation: This study adds to the growing body of evidence showing the benefit to HIV-positive patients of early enrolment in care and initiation of antiretroviral therapy. Funding: Bill & Melinda Gates Foundation. © 2015 Nsanzimana et al. Open Access article distributed under the terms of CC BY-NC-SA.


Stefan D.C.,University of Cape Town | Elzawawy A.M.,Suez Canal University | Khaled H.M.,Cairo University | Ntaganda F.,King Faisal Teaching Hospital | And 5 more authors.
The Lancet Oncology | Year: 2013

The creation and implementation of national cancer control plans is becoming increasingly necessary for countries in Africa, with the number of new cancer cases per year in the continent expected to reach up to 1·5 million by 2020. Examples from South Africa, Egypt, Nigeria, Ghana, and Rwanda describe the state of national cancer control plans and their implementation. Whereas in Rwanda the emphasis is on development of basic facilities needed for cancer care, in those countries with more developed economies, such as South Africa and Nigeria, the political will to fund national cancer control plans is limited, even though the plans exist and are otherwise well conceived. Improved awareness of the increasing burden of cancer and increased advocacy are needed to put pressure on governments to develop, fund, and implement national cancer control plans across the continent. © 2013 Elsevier Ltd.


PubMed | Institute of HIV Disease Prevention and Control, Ministry of Health, Swiss Tropical and Public Health Institute, World Health Organization and 4 more.
Type: Journal Article | Journal: The lancet. HIV | Year: 2015

Continued debate exists about whether initiation of antiretroviral therapy (ART) in symptom-free patients at higher baseline CD4 cell counts results in important clinical benefits. We aimed to examine to what extent baseline CD4 cell count at linkage to HIV care and at ART initiation predicts mortality in adults with HIV in Rwanda.We included data for patients with HIV in Rwanda who were aged 15 years or older and linked to care or initiated ART between Jan 1, 1997, and April 30, 2014, from nationally representative databases. We analysed the effect on mortality of baseline CD4 cell count at ART initiation and at linkage to care. Follow-up time was measured from time of ART initiation and from linkage to HIV care to study exit. To account for effect modification by time, we stratified by era of linkage (before 2008 vs 2008 or after) and for other indications for initiation of ART. We also stratified CD4 cell count by indication to initiate ART other than CD4 cell count status. We used Cox proportional hazard regressions to examine the effect of CD4 cell count at linkage and at ART initiation on mortality.Our analysis was based on data from 50,147 patients who initiated ART and 72,061 patients linked to care. In the late era (2008 and after), linkage to care at a CD4 cell count of 100-199 cells per L without any further indication was associated with higher mortality than linkage at 200-349 cells per L (hazard ratio [HR] 137, 95% CI 095-197); the effect was much the same for initiation of ART in this CD4 stratum (137, 092-204). For higher CD4 strata, linkage to care at 500 cells per L or more was protective (053, 039-072), whereas the reported effect of initiation of ART on mortality was not distinguishable from chance alone (082, 021-320).Efforts are needed to link and retain patients early in pre-ART HIV care. In settings where ART is not yet available for immediate treatment, retention in a strong pre-ART programme is effective at improving survival.The Bill & Melinda Gates Foundation.


PubMed | University of British Columbia, Institute of HIV Disease Prevention and Control, Swiss Tropical and Public Health Institute, Harvard University and College of Medicine and Health Sciences, University of Rwanda
Type: Journal Article | Journal: The lancet. HIV | Year: 2015

Rwanda has made remarkable progress towards HIV care programme with strong national monitoring and surveillance. Knowledge about the HIV care continuum model can help to improve outcomes in patients. We aimed to quantify engagement, mortality, and loss to follow-up of patients along the HIV care continuum in Rwanda in 2013.We collated data for individuals with HIV who participated in the national HIV care programme in Rwanda and calculated the numbers of individuals or proportions of the population at each stage and the transition probabilities between stages of the continuum. We calculated factors associated with mortality and loss to follow-up by fitting Cox proportional hazards regression models, one for the stage of care before antiretroviral therapy (ART) initiation and another for stage of care during ART.An estimated 204,899 individuals were HIV-positive in Rwanda in 2013. Among these individuals, 176,174 (86%) were in pre-ART or in ART stages and 129,405 (63%) had initiated ART by the end of 2013. 821% (95% CI 807-834) of patients with viral load measurements (n=3066) were virally suppressed (translating to 106,371 individuals or 52% of HIV-positive individuals). Mortality was 06% (304 patients) in the pre-ART stage and 10% (1255 patients) in the ART stage; 2247 (39%) patients were lost to follow-up in pre-ART stage and 2847 (22%) lost in ART stage. Risk factors for mortality among patients in both pre-ART and ART stages included older age, CD4 cell count at initiation, and male sex. Risk factors for loss to follow-up among patients at both pre-ART and ART stages included younger age (age 10-29 year) and male sex.The HIV care continuum is a multitrajectory pathway in which patients have many opportunities to leave and re-engage in care. Knowledge about the points at which individuals are most likely to leave care could improve large-scale delivery of HIV programmes.The Bill & Melinda Gates Foundation.


PubMed | Institute of HIV Disease Prevention and Control, University of Cape Town, University of British Columbia, Harvard University and 2 more.
Type: Journal Article | Journal: The Lancet. Global health | Year: 2015

Rwanda has achieved substantial progress in scaling up of antiretroviral therapy. We aimed to assess the effect of increased access to antiretroviral therapy on life expectancy among HIV-positive patients in two distinct periods of lower and higher antiretroviral therapy coverage (1997-2007 and 2008-11).In a retrospective observational cohort study, we collected clinical and demographic data for all HIV-positive patients enrolled in care at 110 health facilities across all five provinces of Rwanda. We included patients aged 15 years or older with a known enrolment date between 1997 and 2014. We constructed abridged life tables from age-specific mortality rates and life expectancy stratified by sex, CD4 cell count, and WHO disease stage at enrolment in care and initiation of antiretroviral therapy.We included 72,061 patients in this study, contributing 213,983 person-years of follow-up. The crude mortality rate was 334 deaths per 1000 person-years (95% CI 327-342). Life expectancy for the overall cohort was 256 additional years (95% CI 251-261) at 20 years of age and 233 additional years (95% CI 229-237) at 35 years of age. Life expectancy at 20 years of age in the period of 1997-2007 was 204 additional years (95% CI 195-213); for the period of 2008-11, life expectancy had increased to 256 additional years (95% CI 248-264). Individuals enrolling in care with CD4 cell counts of 500 cells per L or more, and with WHO disease stage I, had the highest life expectancies.This study adds to the growing body of evidence showing the benefit to HIV-positive patients of early enrolment in care and initiation of antiretroviral therapy.Bill & Melinda Gates Foundation.


PubMed | Stanford University, Institute of HIV Disease Prevention and Control and Precision Global Health
Type: Journal Article | Journal: BMC infectious diseases | Year: 2016

HIV is the leading cause of death among adults in sub-Saharan Africa. However, mortality along the HIV care continuum is poorly described. We combine demographic, epidemiologic, and health services data to estimate where are people with HIV dying along Rwandas care continuum.We calibrated an age-structured HIV disease and transmission stochastic simulation model to the epidemic in Rwanda. We estimate mortality among HIV-infected individuals in the following states: untested, tested without establishing care in an antiretroviral therapy (ART) program (unlinked), in care before initiating ART (pre-ART), lost to follow-up (LTFU) following ART initiation, and retained in active ART care. We estimated mortality among people living with HIV in Rwanda through 2025 under current conditions, and with improvements to the HIV care continuum.In 2014, the greatest portion of deaths occurred among those untested (35.4%), followed by those on ART (34.1%), reflecting the large increase in the population on ART. Deaths among those LTFU made up 11.8% of all deaths among HIV-infected individuals in 2014, and in the base case this portion increased to 18.8% in 2025, while the contribution to mortality declined among those untested, unlinked, and in pre-ART. In our model only combined improvements to multiple aspects of the HIV care continuum were projected to reduce the total number of deaths among those with HIV, estimated at 8177 in 2014, rising to 10,659 in the base case, and declining to 5,691 with combined improvements in 2025.Mortality among those untested for HIV contributes a declining portion of deaths among HIV-infected individuals in Rwanda, but the portion of deaths among those LTFU is expected to increase the most over the next decade. Combined improvements to the HIV care continuum might be needed to reduce the number of deaths among those with HIV.

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