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MAJOR ARTICLE HIV/AIDS Early Warning Indicators for HIV Drug Resistance in Adults in South Africa at 2 Pilot Sites, 2008–2010 Nomathemba M. Dube,1,2,3 Khin S. Tint,3 and Robert S. Summers1,4 1 Medunsa National Pharmacovigilance Centre, Medunsa Campus, University of Limpopo, Pretoria, 2Centre for HIV/STIs, National Institute for Communicable Diseases of the National Health Laboratory Services, 3South African Field Epidemiology and Laboratory Training Programme, National Institute for Communicable Diseases of the National Health Laboratory Services, Johannesburg, and 4Department of Pharmacy, Faculty of Health Sciences, Medunsa Campus, University of Limpopo, Pretoria, South Africa (See the Editorial Commentary by Rossouw on pages 1615–7.) Background. Approximately 5.2 million people in South Africa were infected with human immunodeficiency virus (HIV) by the year 2010, with just over 30% initiated on highly active antiretroviral therapy by 2011. With such numbers involved, the potential for the emergence of HIV drug resistance (HIVDR) is high. This study piloted early warning indicators (EWIs) for HIVDR at 2 clinics in South Africa. Methods. HIV-infected individuals aged ≥15 years and receiving antiretroviral drugs were enrolled into this cohort study between March 2008 and February 2010. All analyses were performed using the 2012 World Health Organization EWI score card. Results. A total of 1144 subjects were enrolled. Clinic A reached the target for 2 of the 5 EWIs but missed the desired target for on-time pill pickup, pharmacy stockouts, and virological suppression. Clinic B reached the target for 1 of 4 EWIs, namely, dispensing practices. Targets were missed for on-time pill pickup, retention in care, and virological suppression. Pharmacy stockouts could not be calculated at this site. Conclusions. Actual performance against the levels that the pilot sites should reach to minimize HIVDR was low. Improvements in follow-up procedures, internal adherence support, monitoring for drug stockouts, and adherence are all aspects that need support to ensure that all records are complete. This pilot study may help to inform the South African government as EWI monitoring is implemented. Keywords. HIV; early warning indicators; drug resistance; antiretroviral medicines; pharmacovigilance. By 2010, 5.2 million people in South Africa were infected with human immunodeficiency virus (HIV), representing approximately 80% of all HIV-infected persons in low and middle-income countries [1, 2]. Scale-up of antiretroviral therapy (ART) in South Africa has been impressive, with >920 000 individuals receiving ART by 2009 and an additional 300 000 initiated on treatment Received 29 August 2013; accepted 22 January 2014; electronically published 27 February 2014. Correspondence: Nomathemba Michell Dube, MSc (Med), MPH, Medunsa National Pharmacovigilance Centre, University of Limpopo, PO Box 172, Medunsa, Pretoria, South Africa ([email protected]). Clinical Infectious Diseases 2014;58(11):1607–14 © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: [email protected]. DOI: 10.1093/cid/ciu109 between 2010 and 2011. This number will increase further as South Africa rolls out ART to individuals with CD4 cell counts of <350 cells/µL and aims to initiate at least 80% of eligible patients on ART, with 70% alive and on treatment 5 years after initiation as stated in the 2012– 2016 National Strategic Plan [3, 4]. The use of ART in the public sector since 2004 has been guided by the National Department of Health’s Operational Plan for Comprehensive HIV and AIDS Care, Management, and Treatment [5], revised in 2010 [6]. This plan states that all new patients needing treatment must be initiated on first-line antiretroviral (ARV) regimens. The recommended South African first-line regimens contain stavudine (excluded from 2010 guideline revision), zidovudine, or tenofovir (introduced in 2010 guideline revision) plus lamivudine and either efavirenz or nevirapine. HIV/AIDS • CID 2014:58 (1 June) • 1607 Unfortunately, most of these life-saving medicines have adverse effects that cause some patients to adhere poorly to treatment or to discontinue therapy altogether [7–9]. Treatment interruptions that include late ARV pickup and drug stockouts may result in the selection of drug-resistant HIV [10]. Poor patient care, reflected by inappropriate prescribing or dispensing practices, inappropriate switching of ARVs, and a high HIV RNA level (>1000 copies/mL) at 12 months, may also contribute to the risk of the emergence of population-level HIV drug resistance (HIVDR) [10]. In 2006, the World Health Organization (WHO) formulated clinic-based HIVDR early warning indicators (EWIs) [10]. Since 2004, 2017 clinics in 50 countries have monitored for EWIs. Of 907 clinics monitored in Africa until 2010, 74% met the target of 100% of subjects receiving ARVs in compliance with national or WHO guidelines, 61% retained subjects on appropriate therapy 12 months after initiation, 15% had subjects pick up ARVs on-time, and 96% had the targeted number of subjects suppressing their viral load (VL) at 12 months [10]. Sigaloff et al [11] have published a study investigating EWIs for population-based monitoring of HIVDR at 13 sentinel sites located in 6 African countries, including South Africa. However, country-specific performances of EWIs were not highlighted [11]. Our study aimed to assess the feasibility of EWI monitoring in South Africa by piloting the analysis from routinely collected data at 2 public sector sites. METHODS Five WHO-suggested EWIs were monitored following 2012 guidance from the report of the Early Advisory Indicator Panel meeting [12]. Data to calculate EWIs were sampled and abstracted from a pharmacovigilance cohort surveillance study database established in 2006 with the main aim of monitoring for adverse drug reactions in subjects taking ARV drugs. All subjects were HIV-infected, aged ≥15 years, and receiving ARVs at 1 of 2 government-owned pilot sites in South Africa. Clinics A and B, situated in Gauteng and Limpopo provinces, respectively, were selected for inclusion into the surveillance study based on the large population size serviced, which reflected patient demographics in each province. Also, adequate human resources were dedicated to the pharmacovigilance program at these clinics with a minimum of 2 full-time medical practitioners assigned to the treatment program. Subject Enrollment Into the Surveillance Study On-site coordinators used systematic random sampling to enroll patients into the study using the following formula: [total number of patients presenting at the clinic each day / number of patients that coordinator can handle per day = select every • CID 2014:58 (1 June) Sampling of Subjects for EWI Calculations The 2012 WHO sampling guidance was followed to provide generalizable results to the clinics from which data were abstracted. The 95% confidence interval (CI) according to this sampling guidance was ±7% [10]. The sample size was calculated based on the total number of patients initiated on ART at each site at 12-month intervals between March 2008 and February 2010 inclusive. Data Management and Analysis Data capturers at the Pharmacovigilance Centre entered data into a Structured Query Language database. Data from March 2008 and February 2010 were abstracted using the WHO’s 2012 data abstraction tool and imported into Epi Info 3.5.1 (Centers for Disease Control and Prevention) [13], from which validation checks were performed. The data were verified by comparing them with the original record and, where possible, with the SOZO database, which houses patient records at many public ARV treatment sites in the country. Results were reported using the EWI scorecard [12]. Details of the EWIs that were calculated in this study are shown in Table 1. Ethical Approval Study Design and Study Setting 1608 nth patient (usually every 10th–15th patient)]. Patients who agreed to participate signed an informed consent form and were not given any preferential treatment at the clinic from which they were enrolled. • HIV/AIDS The project was approved by the Medunsa Research Ethics Committee at the University of Limpopo. RESULTS Profiles of Pilot Sites Profiles of the pilot sites were compiled to support interpretation of EWI results (Table 2). Although both pilot sites began operating in June 2004, clinic A initiated 64.3% (1413/2196) more subjects on ART during the study period than clinic B. The staff-to-patient ratio at the 2 clinics was noticeably different (1:515 at clinic A and 1:129 at clinic B). A total of 1144 subjects consented to be enrolled into the pharmacovigilance study between March 2008 and February 2010. Of the 1144 subjects enrolled, 542 (47.4%) were from clinic A and 602 (52.6%) from clinic B. More females were enrolled (777/1144 [67.9%]) than males (367/1144 [32.1%]). Despite the absence of procedures to follow up with patients who missed scheduled appointments at clinic B, adherence support was available. This support was provided by an external organization, unlike that provided by internal counselors and nurses at clinic A. Self-confessed or suspected nonadherent Table 1. Early Warning Indicators Used to Assess HIV Drug Resistance Prevention at 2 Pilot Sites, March 2008–February 2010 2012 WHO Early Warning Indicators EWI Indicator (WHO Targets) WHO Definition [8] Numerator Denominator 1 On-time pill pickup (Red: <80%; Amber: 80%–90%; Green: ≥90%) Percentage of patients who picked up prescribed ARV drugs on time All patients enrolled into the study who picked up all their prescribed ARV drugs at the first drug pickup after HAART initiation on the scheduled date. (A grace period of 2 days before and after scheduled drug pickup date was given for this calculation.) All patients enrolled into the study who initiated ART between March 2008 and February 2010 inclusive. This value excluded patients known to be deceased and transferred out between baseline and first scheduled pill pickup after initiation. 2 Retention in care (Red: <75%; Amber: 75%–85%; Green: ≥85%) Percentage of patients known to be alive and on treatment 12 mo after ART initiation All patients enrolled into the study that are alive and on treatment 12 mo after ART initiation. 3 Pharmacy stockouts (Red: <100%; Green: 100%) Percentage of months in a designated year in which there were no ARV drug stockouts Total number of months in a designated year, ie, March 2008– February 2009 and March 2009– February 2010, in which there were no stockout days of any ARV drug as recorded on pharmacy stock cards. All patients enrolled into the study who initiated ART between March 2008 and February 2010. This value excluded patients known to be transferred out before their 12 mo date. 12 mo. 4 Dispensing practices (Red: >0%; Green: 0%) Percentage of patients prescribed or picking up mono- or dual ARV therapy All patients enrolled in the study that were initiated on a regimen consisting of 1 or 2 ARV drugs. All patients enrolled into the study who initiated ART between March 2008 and February 2010. 5 Virological suppression (Red: <70%; Amber: 70%–85%; Green: ≥85%) Percentage of patients receiving ART at the site after the first 12 mo of ART whose viral load is <1000 copies/mL All patients enrolled into the study who are still taking ART at 12 mo and who have a viral load of <1000 copies/mL done between 11–15 mo after ART initiation. All patients enrolled into the study who initiated ART between March 2008 and February 2010. This value excluded patients known to be transferred out before their 12 mo date or patients with viral loads done <9 mo or >15 mo after initiation. The score-card colors indicate performance levels reached at the facility for a particular indicator. “Red” indicates poor performance (below desired level); “Amber” is for fair performance (not yet at desired level); and “Green” reflects excellent performance (achieving desired level). Abbreviations: ART, antiretroviral therapy; ARV, antiretroviral; EWI, early warning indicator; HAART, highly active antiretroviral therapy; WHO, World Health Organization. patients at clinic B were identified and referred to this external organization for support. The onus was upon the subject to visit this organization to access its services. An ARV pharmacy was located within each clinic. Procedures to monitor report and act on any drug stockouts that occurred were in place at both pharmacies. Although free services were provided at both clinics, subjects visiting clinic B had to travel longer distances (up to 32 km), using more inconvenient transportation (buses), and wait for longer periods (up to 45 minutes) to pick up medication from the pharmacy compared with subjects who attended clinic A. Most patient records at clinic A were captured on SOZO, whereas those at clinic B were paper-based. More than 60% of VL results at clinic B were missing from subject files. Overall, 99.7% (1141/1144) of subjects enrolled in the pharmacovigilance study were initiated on first-line ARV regimens as stipulated by the South African national guidelines of 2010 (Figure 1). More than 80% of subjects at both clinics were initiated on regimen 1a (Figure 1). Twenty-nine of the 1144 subjects (2.5%) were transferred out during the first 12 months of treatment. Of the remaining subjects, 77.0% (858/1115) were retained on first-line regimens 12 months after initiation. Clinic A retained a higher percentage of subjects on first-line regimens (87%) compared with clinic B (68%) (Figure 2). 2012 Early Warning Indicators EWI 1: On-time Pill Pickup After accounting for deaths (24/1144) and transfers out (1/1144) between the baseline and first scheduled pill pickup dates after initiation, 3.1% (35/1119) of subjects did not return to collect their ARV medicines after their baseline pickup. Overall, 75.6% (846/1119) collected their medication on time (ie, within 2 days HIV/AIDS • CID 2014:58 (1 June) • 1609 Table 2. Pilot Site Profiles of Clinics A and B Pilot Site Characteristic Clinic A (%) Clinic B (%) Clinic statistics Date when facility began providing ARVs June 2004 June 2004 3609 2021 2196 1022 No. of patients initiated on ART at site Year 1 (March 2008–February 2009) 1588 1174 No. of patients enrolled into study Year 1 (March 2008–February 2009) Year 2 (March 2009–February 2010) 542 (15.0) 319 (15.8) 602 (27.4) 324 (31.7) Year 2 (March 2009–February 2010) 223 (14.0) 278 (23.7) 7 17 No. of ARV prescribing staff No. of ARV initiation staff 3 3 5 5 No. of ARV dispensing staff (pharmacists) Staff-to-patient ratio 2 3 1:515 1:129 Present Yes. Internal support groups present Absent Yes. External support groups present Staff statistics No. of HIV care providers (nurses, doctors, physicians, clinical officers) Patient support information Procedures to follow-up patients Adherence support provided? General information Procedures for ARV drug shortages Monitoring Bin cards Stock-cards Drug controller Pharmacy store manager Use alternative drug dosages, eg, 2 × 125 mg instead of 1 × 250 mg or borrow from neighboring clinics Issue <1 month’s supply and request patient to return for drug collection again or borrow from neighboring clinics 2–20 km 2–32 km Public taxis Buses Waiting times for routine ART appointment at clinic (minimummaximum) 60–120 min Not stipulated Waiting times for ART drug pickups (minimum-maximum) 30–35 min 40–45 min Person to report to Managing drug stockouts Distance traveled by patients to clinic (minimum-maximum) Most common means of transport used Abbreviations: ART, antiretroviral therapy; ARV, antiretroviral; HIV, human immunodeficiency virus. of their scheduled pickup date). Those who picked up their pills late collected their medication after a median of 8.15 months (interquartile range [IQR], 6.15–12.45 months) after treatment initiation at clinic A and 9.56 months (IQR, 6.09–13.51 months) at clinic B. According to the EWI score cards, both sites were in the red zone (<80% on-time pill pickups) and exhibited poor performance for this indicator (Figure 3). Approximately 7% (39/542) of subjects at this clinic were lost to follow-up and 3.1% (17/542) were dead within the first 12 months of treatment. Due to high rates of loss to follow-up (125/602 [31.3%]) and deaths (31/602 [5.1%]) during the first 12 months after initiation at clinic B, 73.6% (435/591) of subjects were retained in care there (amber zone, fair performance) (Figure 3). EWI 2: Retention in Care Clinic A retained 89.3% (468/524) of subjects in care 12 months after initiation (≥85%, excellent performance; Figure 3). EWI 3: Pharmacy Stockouts At clinic A, drug stockouts were experienced at the main hospital pharmacy that supplies the ARV clinic pharmacy. The main 1610 • CID 2014:58 (1 June) • HIV/AIDS (4 months), nevirapine (3 months), lamivudine (2 months), stavudine (2 months), and tenofovir (1 month). Clinic A was not directly affected by these stockouts because the main hospital pharmacy reordered stock before the clinic pharmacy ran out of the medicines they had. Clinic B monitored for drug stockouts using stock-cards. These cards could not be obtained from the pharmacy. This indicator was therefore not calculated for this facility. Figure 1. Highly active antiretroviral therapy initiation regimens of subjects enrolled into the pharmacovigilance surveillance study, March 2008– February 2010 (N = 1144). *Drug combination dependent on prescriber. First-line regimens: 1a (stavudine, lamivudine, efavirenz), 1b (stavudine, lamivudine, nevirapine), 1c (zidovudine, lamivudine, efavirenz), 1d (zidovudine, lamivudine, nevirapine), A1 (tenofovir, lamivudine, efavirenz). Second-line regimen: 2 (zidovudine, didanosine, lopinavir/ritonavir). Abbreviations: ART, antiretroviral therapy; NS, nonstandard regimen. hospital pharmacy for clinic A was in the red zone (<100%, poor performance) for this indicator and scored an average of 54.2% due to stockouts experienced in 11 of the 24 months observed in this study (March 2008 to February 2009: 5 of 12 months; March 2009 to February 2010: 6 of 12 months). In 9 of these 11 months, drugs out of stock (≥1 drug per month) were those that are part of first-line regimens, namely, efavirenz EWI 4: Dispensing Practices Both pilot sites initiated all study subjects on highly active antiretroviral therapy (HAART) as recommended by the South African initiation guidelines (Figure 3) as opposed to monoor dual therapy. Both clinic A and B scored in the green zone (0%, excellent performance) for this indicator. EWI 5: Virological Suppression In clinic A, 11- to 15-month VL results were available for 90.0% (476/529) of subjects. Of the subjects with no VL result, 5.7% (3/53) of them died within the first 12 months of initiating HAART and therefore had no VL recorded. Reasons why VLs were missing for the remaining subjects at clinic A are unknown. In clinic B, more than half of the subjects (62.2% [367/590]) had missing VLs, of whom 6.8% (25/367) had died within 12 months of initiation. Of the subjects with 11- to 15-month VL results available, clinic A achieved an 81.5% (388/476) VL suppression rate (amber zone) whereas the rate at clinic B was 65.9% (147/ 223). Of all the subjects who achieved VL suppression, 96.4% (516/535) had been on first-line ARV regimens since ART Figure 2. Flow chart illustrating subjects retained on first-line therapy at clinics A and B, March 2008–February 2010. Abbreviation: LTFU, lost to follow-up. HIV/AIDS • CID 2014:58 (1 June) • 1611 Figure 3. Yearly performance of human immunodeficiency virus drug resistance early warning indicators at each pilot site, March 2008–February 2010. Abbreviations: ART, antiretroviral therapy; EWI, early warning indicator; N/A, not available. initiation. Our findings show that an association exists between retention on first-line regimens for at least 12 months after initiation and VL suppression at 11–15 months (χ2 = 22.19, P = .000). Subjects receiving ARV medicines at clinics A and B who remained exclusively on first-line regimens for the first 12 months after initiation were 1.28 times more likely to achieve VL suppression rates of <1000 copies/mL between 11 and 15 months after initiation than subjects whose regimens were non-first-line within the first 12 months of initiation (95% CI, 1.21–2.36). Compliance With HIVDR EWIs, by Year The number of subjects picking up treatment on-time improved at both sites from the year 2008–2009 to 2009–2010 (Figure 3). Clinic A retained more subjects in care in both years compared with clinic B. In clinic B, a decrease in subjects retained in care was observed due to a surge in subjects lost to follow-up between 2008–2009 and 2009–2010, that is, 16.1%–27.0% (χ2 = 10.51, P = .001). Although stockouts increased at clinic A in 2009–2010, neither clinic A or B dispensed mono- or dual therapy. Despite both facilities having missing VLs and not reaching the desired VL suppression target (≥85%), the proportion of subjects achieving VL suppression at both sites increased in 2009–2010 (Figure 3). DISCUSSION Monitoring EWIs of HIVDR provides information on the functioning of ART clinics and programs. The present pilot study 1612 • CID 2014:58 (1 June) • HIV/AIDS was the first of its kind in the country and aimed to assess the feasibility of the use of EWIs in this setting. Despite the fact that both pilot sites initiated the majority of their subjects on first-line ARV regimens, some subjects were initiated on other HAART drug combinations. The reason for initiating these subjects on these drug combinations may have been the anticipation of certain toxicities such as exacerbated peripheral neuropathy if, for example, subjects with HIV-related peripheral neuropathy were initiated on first-line drug combinations containing stavudine. Clinic EWI performance seemed to be inversely related to staff-to-patient ratio. Despite a lower staff-to-patient ratio at clinic A compared with clinic B, clinic A performed better for all EWIs. This result has led us to believe that interventions for patient care in place at clinics had a more direct influence on EWI performance than the staff-to-patient ratio. It is worth conducting a case series study to investigate if the availability of follow-up procedures as well as internal adherence support at clinic A contributed to excellent subject retention there, compared with fair performance at clinic B where follow-up services are not available and adherence support is external. Although the national guidelines require patients to attend 3 counseling sessions before HAART initiation, in particular, including education on the importance of adherence, both clinics still had subjects picking up medication late on the first visit after the baseline pickup and some not returning at all after baseline pickup. This situation suggests that more must be done at the clinics to strengthen adherence support. As a result of this finding, research to investigate reasons for treatment interruption is under way. This research will also determine if distance from the clinic, mode of transport used, and long waiting times at clinics are contributing factors to poor on-time pill pickup. Two studies in South Africa, by Maskew et al and Wang et al , investigated factors that contributed to treatment interruptions in their cohorts [14, 15]. Financial difficulties in obtaining treatment (eg, transport costs) and pregnancy at ART initiation were significant contributors. Studies by Bisson et al and El-Khatib et al concluded that pharmacy refill adherence estimates are as accurate as CD4 counts for the identification of patients’ risk of virological and immunologic failure before the event occurs [16, 17]. It is therefore crucial to address poor on-time pill pickup at the clinics to prevent treatment failure. For future EWI monitoring, introducing a CD4 count EWI may be a more accurate measure for HIVDR emergence than on-time pill pickup. Efforts were made to obtain stock-card records from clinic B. Due to restrictions to the access of stock cards at the facility; pharmacy stockouts could not be calculated. ARV stockouts are an ongoing challenge in South Africa. Stockouts experienced in the hospital A pharmacy were mainly of drugs that constitute first-line regimens. With the country using approximately 80% of worldwide ARV drug supplies (Professor Steven Miller, personal communication), failure to strengthen ARV drug forecasting, procurement, and distribution, coupled with the scaleup of ARV rollout, will result in more treatment interruptions and rapid emergence of HIVDR. The National Department of Health is urgently trying to install a countrywide computer software system that will link healthcare facilities with drug depots and suppliers to relieve ongoing essential drugs stockouts [18]. We believe that ability to prevent drug stockout in clinic A contributed directly to EWI performance levels. At clinic A, the use of bin cards and the availability of a drug controller at the main hospital pharmacy alerted the pharmacists to timely reorder. Besides, dispensing practices were excellent for clinic A because all drug combinations were available to give triple therapy. Although clinic A has lower staff-to-patient ratio, it addressed the challenges of maintaining ARV supply as shown in the study done in Malawi [19]. Although pill pickup by subjects was not timely, virological suppression was fair. This is in consensus with Harrigan et al, who showed that when compared to subjects with relatively high (80%–90%) and essentially perfect (≥95%) refill estimates, those at low risk of harboring HIVDR mutations are those with low drug refill estimates (0%–20%) [20]. Lack of funds to hire a data entry clerk is the main reason why the record system at clinic B is paper-based. This system resulted in the majority of VL results disappearing before they could be entered into the subjects’ files. In addition to missing VLs, the number of subjects achieving the desired level of VL suppression at clinic B was very low. The reason for this result may have been low levels of patient retention on first-line regimens for ≥12 months after initiation. This factor may have been attributed to by external adherence counseling, which may not have been easily accessible at clinic B. This aspect may need to be investigated further. A major limitation to this study was the unavailability of stockout data from clinic B. This situation prevented us from obtaining a true reflection of drug supply continuity there. The South African government intends to introduce EWI monitoring at public-sector ART treatment sites and to integrate EWI data abstraction into routine reporting of all ART clinics. Results of this pilot study may provide valuable information of weaknesses in the current system that may be improved before EWI monitoring is implemented in the country as a whole. Most levels of performance, as measured by EWIs, that the pilot sites should be reaching to minimize HIVDR were not achieved. Clinic A was on target for retention of subjects in care at 12 months as well as dispensing practices, whereas clinic B met the target for dispensing practices only. These results emphasize 3 things: (1) the importance of implementing patient follow-up coupled with internal ongoing drug adherence support to ensure patients understand the dangers of treatment interruptions; (2) the need for continuous training and supervision support of health practitioners to prevent premature drug switches; and (3) the necessity for operational research to strengthen health systems such as the ability to prevent stockouts and establishing an electronic database at health facilities. In conclusion, EWI monitoring is feasible in South Africa; however, the National Department of Health needs to ensure that the electronic data capturing systems are available at all facilities and continuously updated before EWI results can accurately reflect site performance. Additionally, information regarding drug stock must be included in the electronic databases and made available on request, as the availability of drug stock is one of the key factors in preventing HIVDR. Notes Acknowledgments. Naome Mberi assisted with data abstraction. Michael R. Jordan, Lynn Morris, and Gillian Hunt reviewed this manuscript. The Foundation for Professional Development contributed to the development of the database. Author contributions. N. M. D., R. S. S., and K. S. T. were involved in the conceptualization of this study. N. M. D. was involved in the study design, statistical analysis, results interpretation, and preparation of this report. All authors were involved with revision of this report. Disclaimer. The contents of this manuscript are solely the responsibility of the authors and not of the funding agencies. Financial support. This work was supported by the South African Field Epidemiology and Laboratory Training program funded by the Centers for Disease Control and Prevention (3U2GPS001328-04) and the South African National Department of Health. Potential conflicts of interest. All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed. HIV/AIDS • CID 2014:58 (1 June) • 1613 References 1. Statistics South Africa. Mid-year population estimates 2010. Available at: http://www.statssa.gov.za/publications/P0302/P03022010.pdf. Accessed 12 April 2012. 2. United Nations Joint Programme on HIV/AIDS. AIDS at 30: nations at a crossroad. Available at: http://www.unaids.org/unaids_resources/ aidsat30/aids-at-30.pdf. Accessed 17 May 2012. 3. World Health Organization. Rapid advice: antiretroviral therapy for HIV infection in adults and adolescents. 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