Journal Article > ResearchFull Text
JMIR Public Health Surveill. 2019 March 20
Rice B, Boulle AM, Schwarcz S, Shroufi A, Rutherford G, et al.
JMIR Public Health Surveill. 2019 March 20
The move toward universal provision of antiretroviral therapy and the expansion of HIV viral load monitoring call into question the ongoing value of CD4 cell count testing and monitoring. We highlight the role CD4 monitoring continues to have in guiding clinical decisions and measuring and evaluating the epidemiology of HIV. To end the HIV/AIDS epidemic, we require strategic information, which includes CD4 cell counts, to make informed clinical decisions and effectively monitor key surveillance indicators.
Protocol > Research Study
Fernandez MAL, Schomaker M, Mason PR, Fesselet JF, Baudot Y, et al.
2012 June 18
BACKGROUND
In highly populated African urban areas where access to clean water is a challenge, water source contamination is one of the most cited risk factors in a cholera epidemic. During the rainy season, where there is either no sewage disposal or working sewer system, runoff of rains follows the slopes and gets into the lower parts of towns where shallow wells could easily become contaminated by excretes. In cholera endemic areas, spatial information about topographical elevation could help to guide preventive interventions. This study aims to analyze the association between topographic elevation and the distribution of cholera cases in Harare during the cholera epidemic in 2008 and 2009.
METHODS
We developed an ecological study using secondary data. First, we described attack rates by suburb and then calculated rate ratios using whole Harare as reference. We illustrated the average elevation and cholera cases by suburbs using geographical information. Finally, we estimated a generalized linear mixed model (under the assumption of a Poisson distribution) with an Empirical Bayesian approach to model the relation between the risk of cholera and the elevation in meters in Harare. We used a random intercept to allow for spatial correlation of neighboring suburbs.
RESULTS
This study identifies a spatial pattern of the distribution of cholera cases in the Harare epidemic, characterized by a lower cholera risk in the highest elevation suburbs of Harare. The generalized linear mixed model showed that for each 100 meters of increase in the topographical elevation, the cholera risk was 30% lower with a rate ratio of 0.70 (95% confidence interval=0.66-0.76). Sensitivity analysis confirmed the risk reduction with an overall estimate of the rate ratio between 20% and 40%.
CONCLUSION
This study highlights the importance of considering topographical elevation as a geographical and environmental risk factor in order to plan cholera preventive activities linked with water and sanitation in endemic areas. Furthermore, elevation information, among other risk factors, could help to spatially orientate cholera control interventions during an epidemic.
In highly populated African urban areas where access to clean water is a challenge, water source contamination is one of the most cited risk factors in a cholera epidemic. During the rainy season, where there is either no sewage disposal or working sewer system, runoff of rains follows the slopes and gets into the lower parts of towns where shallow wells could easily become contaminated by excretes. In cholera endemic areas, spatial information about topographical elevation could help to guide preventive interventions. This study aims to analyze the association between topographic elevation and the distribution of cholera cases in Harare during the cholera epidemic in 2008 and 2009.
METHODS
We developed an ecological study using secondary data. First, we described attack rates by suburb and then calculated rate ratios using whole Harare as reference. We illustrated the average elevation and cholera cases by suburbs using geographical information. Finally, we estimated a generalized linear mixed model (under the assumption of a Poisson distribution) with an Empirical Bayesian approach to model the relation between the risk of cholera and the elevation in meters in Harare. We used a random intercept to allow for spatial correlation of neighboring suburbs.
RESULTS
This study identifies a spatial pattern of the distribution of cholera cases in the Harare epidemic, characterized by a lower cholera risk in the highest elevation suburbs of Harare. The generalized linear mixed model showed that for each 100 meters of increase in the topographical elevation, the cholera risk was 30% lower with a rate ratio of 0.70 (95% confidence interval=0.66-0.76). Sensitivity analysis confirmed the risk reduction with an overall estimate of the rate ratio between 20% and 40%.
CONCLUSION
This study highlights the importance of considering topographical elevation as a geographical and environmental risk factor in order to plan cholera preventive activities linked with water and sanitation in endemic areas. Furthermore, elevation information, among other risk factors, could help to spatially orientate cholera control interventions during an epidemic.
Journal Article > ResearchFull Text
S Afr Med J. 2009 September 1
Cornell M, Technau KG, Fairall L, Wood R, Moultrie H, et al.
S Afr Med J. 2009 September 1
OBJECTIVES: To introduce the combined South African cohorts of the International epidemiologic Databases to Evaluate AIDS Southern Africa (IeDEA-SA) collaboration as reflecting the South African national antiretroviral treatment (ART) programme; to characterise patients accessing these services; and to describe changes in services and patients from 2003 to 2007. DESIGN AND SETTING: Multi-cohort study of 11 ART programmes in Gauteng, Western Cape, Free State and KwaZulu-Natal. SUBJECTS: Adults and children (<16 years old) who initiated ART with > or =3 antiretroviral drugs before 2008. RESULTS: Most sites were offering free treatment to adults and children in the public sector, ranging from 264 to 17,835 patients per site. Among 45,383 adults and 6,198 children combined, median age (interquartile range) was 35.0 years (29.8-41.4) and 42.5 months (14.7-82.5), respectively. Of adults, 68% were female. The median CD4 cell count was 102 cells/microl (44-164) and was lower among males than females (86, 34-150 v. 110, 50-169, p<0.001). Median CD4% among children was 12% (7-17.7). Between 2003 and 2007, enrolment increased 11-fold in adults and 3-fold in children. Median CD4 count at enrolment increased for all adults (67-111 cells/microl, p<0.001) and for those in stage IV (39-89 cells/microl, p<0.001). Among children <5 years, baseline CD4% increased over time (11.5-16.0%, p<0.001). CONCLUSIONS: IeDEA-SA provides a unique opportunity to report on the national ART programme. The study describes dramatically increased enrolment over time. Late diagnosis and ART initiation, especially of men and children, need attention. Investment in sentinel sites will ensure good individual-level data while freeing most sites to continue with simplified reporting.
Journal Article > ResearchFull Text
J Int AIDS Soc. 2017 June 23; Volume 20 (Issue 1); DOI:10.7448/IAS.20.1.21327
Fenner L, Atkinson A, Boulle AM, Fox MP, Prozesky HW, et al.
J Int AIDS Soc. 2017 June 23; Volume 20 (Issue 1); DOI:10.7448/IAS.20.1.21327
Chronic immune activation due to ongoing HIV replication may lead to impaired immune responses against opportunistic infections such as tuberculosis (TB). We studied the role of HIV replication as a risk factor for incident TB after starting antiretroviral therapy (ART).
Journal Article > ResearchFull Text
PLOS One. 2013 February 28; Volume 8 (Issue 2); e57611.; DOI:10.1371/journal.pone.0057611
Estill J, Egger M, Johnson LF, Gsponer T, Wandeler G, et al.
PLOS One. 2013 February 28; Volume 8 (Issue 2); e57611.; DOI:10.1371/journal.pone.0057611
OBJECTIVES
Mortality in patients starting antiretroviral therapy (ART) is higher in Malawi and Zambia than in South Africa. We examined whether different monitoring of ART (viral load [VL] in South Africa and CD4 count in Malawi and Zambia) could explain this mortality difference.
DESIGN
Mathematical modelling study based on data from ART programmes.
METHODS
We used a stochastic simulation model to study the effect of VL monitoring on mortality over 5 years. In baseline scenario A all parameters were identical between strategies except for more timely and complete detection of treatment failure with VL monitoring. Additional scenarios introduced delays in switching to second-line ART (scenario B) or higher virologic failure rates (due to worse adherence) when monitoring was based on CD4 counts only (scenario C). Results are presented as relative risks (RR) with 95% prediction intervals and percent of observed mortality difference explained.
RESULTS
RRs comparing VL with CD4 cell count monitoring were 0.94 (0.74-1.03) in scenario A, 0.94 (0.77-1.02) with delayed switching (scenario B) and 0.80 (0.44-1.07) when assuming a 3-times higher rate of failure (scenario C). The observed mortality at 3 years was 10.9% in Malawi and Zambia and 8.6% in South Africa (absolute difference 2.3%). The percentage of the mortality difference explained by VL monitoring ranged from 4% (scenario A) to 32% (scenarios B and C combined, assuming a 3-times higher failure rate). Eleven percent was explained by non-HIV related mortality.
CONCLUSIONS
VL monitoring reduces mortality moderately when assuming improved adherence and decreased failure rates.
Mortality in patients starting antiretroviral therapy (ART) is higher in Malawi and Zambia than in South Africa. We examined whether different monitoring of ART (viral load [VL] in South Africa and CD4 count in Malawi and Zambia) could explain this mortality difference.
DESIGN
Mathematical modelling study based on data from ART programmes.
METHODS
We used a stochastic simulation model to study the effect of VL monitoring on mortality over 5 years. In baseline scenario A all parameters were identical between strategies except for more timely and complete detection of treatment failure with VL monitoring. Additional scenarios introduced delays in switching to second-line ART (scenario B) or higher virologic failure rates (due to worse adherence) when monitoring was based on CD4 counts only (scenario C). Results are presented as relative risks (RR) with 95% prediction intervals and percent of observed mortality difference explained.
RESULTS
RRs comparing VL with CD4 cell count monitoring were 0.94 (0.74-1.03) in scenario A, 0.94 (0.77-1.02) with delayed switching (scenario B) and 0.80 (0.44-1.07) when assuming a 3-times higher rate of failure (scenario C). The observed mortality at 3 years was 10.9% in Malawi and Zambia and 8.6% in South Africa (absolute difference 2.3%). The percentage of the mortality difference explained by VL monitoring ranged from 4% (scenario A) to 32% (scenarios B and C combined, assuming a 3-times higher failure rate). Eleven percent was explained by non-HIV related mortality.
CONCLUSIONS
VL monitoring reduces mortality moderately when assuming improved adherence and decreased failure rates.
Journal Article > ResearchFull Text
PLOS One. 2019 March 12; Volume 14 (Issue 3); e0212405.; DOI:10.1371/journal.pone.0212405
Hwang B, Shroufi A, Gils T, Steele SJ, Grimsrud A, et al.
PLOS One. 2019 March 12; Volume 14 (Issue 3); e0212405.; DOI:10.1371/journal.pone.0212405
BACKGROUND
HIV and TB programs have rapidly scaled-up over the past decade in Sub-Saharan Africa and uninterrupted supplies of those medicines are critical to their success. However, estimates of stock-outs are largely unknown. This survey aimed to estimate the extent of stock-outs of antiretroviral and TB medicines in public health facilities across South Africa, which has the world’s largest antiretroviral treatment (ART) program and a rising multidrug-resistant TB epidemic.
METHODS
We conducted a cross-sectional telephonic survey (October—December 2015) of public health facilities. Facilities were asked about the prevalence of stock-outs on the day of the survey and in the preceding three months, their duration and impact.
RESULTS
Nationwide, of 3547 eligible health facilities, 79% (2804) could be reached telephonically. 88% (2463) participated and 4% (93) were excluded as they did not provide ART or TB treatment. Of the 2370 included facilities, 20% (485) reported a stock-out of at least 1 ARV and/or TB-related medicine on the day of contact and 36% (864) during the three months prior to contact, ranging from 74% (163/220) of health facilities in Mpumalanga to 12% (32/261) in the Western Cape province. These 864 facilities reported 1475 individual stock-outs, with one to fourteen different medicines out of stock per facility. Information on impact was provided in 98% (1449/1475) of stock-outs: 25% (366) resulted in a high impact outcome, where patients left the facility without medicine or were provided with an incomplete regimen. Of the 757 stock-outs that were resolved 70% (527) lasted longer than one month.
INTERPRETATION
There was a high prevalence of stock-outs nationwide. Large interprovincial differences in stock-out occurrence, duration, and impact suggest differences in provincial ability to prevent, mitigate and cope within the same framework. End-user monitoring of the supply chain by patients and civil society has the potential to increase transparency and complement public sector monitoring systems.
HIV and TB programs have rapidly scaled-up over the past decade in Sub-Saharan Africa and uninterrupted supplies of those medicines are critical to their success. However, estimates of stock-outs are largely unknown. This survey aimed to estimate the extent of stock-outs of antiretroviral and TB medicines in public health facilities across South Africa, which has the world’s largest antiretroviral treatment (ART) program and a rising multidrug-resistant TB epidemic.
METHODS
We conducted a cross-sectional telephonic survey (October—December 2015) of public health facilities. Facilities were asked about the prevalence of stock-outs on the day of the survey and in the preceding three months, their duration and impact.
RESULTS
Nationwide, of 3547 eligible health facilities, 79% (2804) could be reached telephonically. 88% (2463) participated and 4% (93) were excluded as they did not provide ART or TB treatment. Of the 2370 included facilities, 20% (485) reported a stock-out of at least 1 ARV and/or TB-related medicine on the day of contact and 36% (864) during the three months prior to contact, ranging from 74% (163/220) of health facilities in Mpumalanga to 12% (32/261) in the Western Cape province. These 864 facilities reported 1475 individual stock-outs, with one to fourteen different medicines out of stock per facility. Information on impact was provided in 98% (1449/1475) of stock-outs: 25% (366) resulted in a high impact outcome, where patients left the facility without medicine or were provided with an incomplete regimen. Of the 757 stock-outs that were resolved 70% (527) lasted longer than one month.
INTERPRETATION
There was a high prevalence of stock-outs nationwide. Large interprovincial differences in stock-out occurrence, duration, and impact suggest differences in provincial ability to prevent, mitigate and cope within the same framework. End-user monitoring of the supply chain by patients and civil society has the potential to increase transparency and complement public sector monitoring systems.
Journal Article > LetterFull Text
Clin Infect Dis. 2014 April 23; Volume 59 (Issue 3); DOI:10.1093/cid/ciu288
Patten GE, Cox V, Stinson K, Boulle AM, Wilkinson LS
Clin Infect Dis. 2014 April 23; Volume 59 (Issue 3); DOI:10.1093/cid/ciu288
Journal Article > ResearchFull Text
AIDS. 2010 September 10; Volume 24 (Issue 14); DOI:10.1097/QAD.0b013e32833d45c5
Cornell M, Grimsrud A, Fairall L, Fox MP, van Cutsem G, et al.
AIDS. 2010 September 10; Volume 24 (Issue 14); DOI:10.1097/QAD.0b013e32833d45c5
OBJECTIVE: Little is known about the temporal impact of the rapid scale-up of large antiretroviral therapy (ART) services on programme outcomes. We describe patient outcomes [mortality, loss-to-follow-up (LTFU) and retention] over time in a network of South African ART cohorts. DESIGN: Cohort analysis utilizing routinely collected patient data. METHODS: Analysis included adults initiating ART in eight public sector programmes across South Africa, 2002-2007. Follow-up was censored at the end of 2008. Kaplan-Meier methods were used to estimate time to outcomes, and proportional hazards models to examine independent predictors of outcomes. RESULTS: Enrolment (n = 44 177, mean age 35 years; 68% women) increased 12-fold over 5 years, with 63% of patients enrolled in the past 2 years. Twelve-month mortality decreased from 9% to 6% over 5 years. Twelve-month LTFU increased annually from 1% (2002/2003) to 13% (2006). Cumulative LTFU increased with follow-up from 14% at 12 months to 29% at 36 months. With each additional year on ART, failure to retain participants was increasingly attributable to LTFU compared with recorded mortality. At 12 and 36 months, respectively, 80 and 64% of patients were retained. CONCLUSION: Numbers on ART have increased rapidly in South Africa, but the programme has experienced deteriorating patient retention over time, particularly due to apparent LTFU. This may represent true loss to care, but may also reflect administrative error and lack of capacity to monitor movements in and out of care. New strategies are needed for South Africa and other low-income and middle-income countries to improve monitoring of outcomes and maximize retention in care with increasing programme size.
Journal Article > ReviewFull Text
Int J Epidemiol. 2016 May 20; Volume 46 (Issue 2); e21.; DOI:doi.org/10.1093/ije/dyw057
Stinson K, Goemaere E, Coetzee D, van Cutsem G, Hilderbrand K, et al.
Int J Epidemiol. 2016 May 20; Volume 46 (Issue 2); e21.; DOI:doi.org/10.1093/ije/dyw057
Journal Article > ResearchFull Text
J Int AIDS Soc. 2017 March 16; Volume 20; DOI:10.7448/IAS.20.4.21668
Davies MA, Tsondai PR, Tiffin N, Eley B, Rabie H, et al.
J Int AIDS Soc. 2017 March 16; Volume 20; DOI:10.7448/IAS.20.4.21668
To evaluate long-term outcomes in HIV-infected adolescents, it is important to identify ways of tracking outcomes after transfer to a different health facility. The Department of Health (DoH) in the Western Cape Province (WCP) of South Africa uses a single unique identifier for all patients across the health service platform. We examined adolescent outcomes after transfer by linking data from four International epidemiology Databases to Evaluate AIDS Southern Africa (IeDEA-SA) cohorts in the WCP with DoH data.