Neil A Martinson

University of the Witwatersrand, Johannesburg, Gauteng, South Africa

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Publications (89)503.31 Total impact

  • The International Journal of Tuberculosis and Lung Disease 08/2014; 18(8). · 2.76 Impact Factor
  • The Journal of infectious diseases. 07/2014;
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    ABSTRACT: The tuberculin skin test (TST) is used to help diagnose tuberculosis (TB) in acutely ill hospitalised children. OBJECTIVE To investigate the potential augmentative effect of topical calcipotriol (a vitamin D analogue) or zinc on TST induration. Three TSTs were performed among 64 hospitalised children; each site was covered with topical aqueous cream (control), calcipotriol or zinc and assessed 24 and 48 h later by investigators blinded to all topical applications. TSTs were reactive in 15 (23.4%) children, of whom 13 (20.3%) were TST-positive. Topical calcipotriol and zinc induced TST positivity in two children with reactive but negative control TSTs. These treatments, however, did not significantly increase TST positivity rates. In children with reactive TSTs, the median 48 h induration diameter was not significantly different between the control, calcipotriol- or zinc-treated groups, which were respectively 12.0 (25%-75% IQR 5.0 - 18.0), 14.0 (25%-75% IQR 10.0 - 15.0) and 12.0 (25%-75% IQR 8.0 - 15.0) mm. Topical treatments did not induce TST reactivity or TST positivity in children with culture-confirmed TB disease (n = 4), human immunodeficiency virus infection (n= 18) or kwashiorkor (n = 9). Topical calcipotriol or zinc does not induce TST reactivity or significantly increase TST positivity rates in acutely ill hospitalised children. However, further studies are required to assess the effects of topical treatments on TST positivity in severely malnourished children.
    The International Journal of Tuberculosis and Lung Disease 04/2014; 18(4):388-93. · 2.76 Impact Factor
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    ABSTRACT: To report the viral load and CD4 count in HIV-infected, antiretroviral naïve, first -time HIV-testers, not immediately eligible for treatment initiation by current South Africa treatment guidelines. This was a cross-sectional study in a high-volume, free-of-charge HIV testing centre in Soweto, South Africa. We enrolled first time HIV testers and collected demographic and risk-behaviour data and measured CD4 count and viral load. Between March and October 2011, a total of 4793 adults attended VCT and 1062 (22%) tested positive. Of the 1062, 799 (75%) were ART naïve and 348/799 (44%) were first-time HIV testers. Of this group of 348, 225 (65%) were female. Overall their median age, CD4 count and viral load was 34 years (IQR: 28-41), 364 (IQR: 238-542) cells/mm3 and 13,000 (IQR: 2050-98171) copies/ml, respectively. Female first time HIV testers had higher CD4 counts (419 IQR: 262-582 vs. 303 IQR: 199-418 cells/mm3) and lower viral loads (9,100 vs. 34,000 copies/ml) compared to males. Of 183 participants with CD4 count >350 cells/mm3, 62 (34%) had viral loads > 10,000 copies/ml. A large proportion of HIV infected adults not qualifying for immediate ART at the CD4 count threshold of 350 cells/mm3 have high viral loads. HIV-infected men at their first HIV diagnosis are more likely to have lower CD4 counts and higher viral loads than women.
    PLoS ONE 01/2014; 9(3):e90754. · 3.53 Impact Factor
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    ABSTRACT: CD4 count is a proxy for the extent of immune deficiency and declines in CD4 count are a measure of disease progression. Decline in CD4 count is an important component: for estimating benefits of ARV treatment; for individual level counselling on the rapidity of untreated disease progression and prognosis; and can be used in planning demand for health services. Our objective is to report CD4 decline and changes in viral load (VL) in a group of HIV-infected adults enrolled in a randomized trial of preventive treatment for TB in South Africa where clade C infection predominates. HIV-infected, tuberculin skin test positive adults who were not eligible for antiretroviral (ARV) treatment were randomized to a trial of preventive treatment from 2003-2005. VL and CD4 count were assessed at enrollment and CD4 counts repeated at least annually. During follow-up, individuals whose CD4 counts decreased to <200 cells/mm3 were referred for antiretroviral therapy (ART) and were analytically censored. 1106 ARV naïve adults were enrolled. Their median age was 30 years and male to female ratio was 1∶5. Median baseline CD4 count was 490 cells/mm3 (IQR 351-675). The overall mean decline in CD4 count was 61 cells/mm3 per annum. Adjusting for age, gender, baseline hemoglobin, smoking and alcohol use had little impact on the estimate of CD4 decline. However, VL at baseline had a major impact on CD4 decline. The percent decline in CD4 count was 13.3% (95% CI 12.0%, 14.7%), 10.6% (95% CI 8.8%, 12.4%), and 13.8% (95% CI 12.1%, 15.5%) per annum for baseline VLs of <10,000 (N = 314), 10,001-100,000 (N = 338), >100,000 (N = 122) copies/ml. Our data suggests that six and a half years will elapse for an individual's CD4 count to decline from 750 to 350 cells/mm3 in the absence of ART.
    PLoS ONE 01/2014; 9(5):e96369. · 3.53 Impact Factor
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    ABSTRACT: To report the incidence rates of TB and HIV in household contacts of index patients diagnosed with TB. A prospective cohort study in the Matlosana sub-district of North West Province, South Africa. Contacts of index TB patients received TB and HIV testing after counseling at their first household visit and were then followed up a year later, in 2010. TB or HIV diagnoses that occurred during the period were determined. For 2,377 household contacts, the overall observed TB incidence rate was 1.3 per 100 person years (95% CI 0.9-1.9/100py) and TB incidence for individuals who were HIV-infected and HIV seronegative at baseline was 5.4/100py (95% CI 2.9-9.0/100py) and 0.7/100py (95% CI 0.3-1.4/100py), respectively. The overall HIV incidence rate was 2.2/100py (95% CI 1.3-8.4/100py). In the year following a household case finding visit when household contacts were tested for TB and HIV, the incidence rate of both active TB and HIV infection was found to be extremely high. Clearly, implementing proven strategies to prevent HIV acquisition and preventing TB transmission and progression to disease remains a priority in settings such as South Africa.
    PLoS ONE 01/2014; 9(4):e95372. · 3.53 Impact Factor
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    JAIDS Journal of Acquired Immune Deficiency Syndromes 01/2014; 65(1):e29-32. · 4.65 Impact Factor
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    ABSTRACT: The prevalence of illicitly traded cigarettes in South Africa has been reported to be 40-50%. However, these estimates do not account for the more nuanced characteristics of the illicit cigarette trade. With the goal of better understanding contraband cigarettes in South Africa, this study piloted three methods for assessing the price, brands, pack features and smoker's views about illicit cigarettes in five cities/towns. Data were collected in June and July 2012. A convenience sample of three South African cities (Johannesburg, Durban and Nelspruit) and two smaller towns (Musina and Ficksburg) were chosen for this study. Three cross-sectional approaches were used to assess the characteristics of contraband cigarettes: (1) a dummy purchase of cigarettes from informal retailers, (2) the collection of discarded cigarette packs and (3) a survey of tobacco smokers. For the purposes of the survey, 40 self-reported smokers were recruited at taxi ranks in each downtown site. Adults who were over the age of 18 were asked to verbally consent to participate in the study and answer a questionnaire administered by a researcher. The leading reason for labelling a pack as illicit in each city/town was the absence of an excise stamp (28.6% overall), and the least common reason was an illegal tar or nicotine level (11.1% overall). The overall proportion of informal vendors who sold illicit cigarettes was 41%. Singles and packs of 20 were consistently cheaper at informal vendors. Survey participants' responses reflected varied perspectives on illicit cigarettes and purchasing preferences. Each approach generated an interesting insight into physical aspects of illicit cigarettes. While this pilot study cannot be used to generate generalisable statistics on illicit cigarettes, more systematic surveys of this nature could inform researchers' and practitioners' initiatives to combat illicit and legal cigarette sales and usage.
    BMJ Open 01/2014; 4(5):e004562. · 1.58 Impact Factor
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    ABSTRACT: Introduction: Globally, hepatitis B virus (HBV) infection is the leading cause of liver-related mortality. Newborn vaccination, maternal antiviral therapy and administering hepatitis B immune globulin shortly after birth can greatly reduce the risk of perinatal and infant infection. However, evidence-based policy regarding these interventions in Africa is hampered by gaps in knowledge of HBV epidemiology. We describe maternal chronic hepatitis B (CHB) prevalence and infant infection during the first year of life within a cohort of women living with HIV. Methods: We recruited and prospectively followed pregnant women living with HIV and their infants from prenatal clinics in an urban area of South Africa. Hepatitis B surface antigen, anti-hepatitis B surface antibodies and HBV DNA were assessed in all women. Hepatitis B testing was also performed at 6 and 52 weeks for all infants born to mothers with either positive surface antigen or detectable HBV DNA. Results: We enrolled 189 women with a median age of 29 years and median CD4 count of 348 cells/mm(3). Fourteen had a positive surface antigen (7.4%), of which six were positive for "e" antigen. An additional three had detectable HBV DNA without positive surface antigen. One infant developed CHB and three others had evidence of transmission based on positive HBV DNA assays. HBV vaccinations were delivered at six weeks of life to all infants. Conclusions: Our findings highlight the risk of peripartum HBV transmission in this setting. Approaches to reducing this transmission should be considered.
    Journal of the International AIDS Society 01/2014; 17(1):18871. · 3.94 Impact Factor
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    ABSTRACT: Many randomized and cohort studies have reported a survival benefit with cotrimoxazole prophylaxis without detecting a difference in tuberculosis (TB) incidence by cotrimoxazole status. However, several in vitro studies have reported that cotrimoxazole possesses anti-TB activity. We sought to compare TB incidence and TB diagnostic yield by cotrimoxazole use among participants in a well characterized cohort of HIV-infected adults living in a high TB prevalence region. We analyzed prospective data from a long-term longitudinal cohort of adults receiving HIV care and TB investigations in Soweto, South Africa. Using longitudinal analysis, we compared total and laboratory confirmed TB incidence by cotrimoxazole status as well as all-cause mortality. In addition, we compared TB culture results by cotrimoxazole status. In a multivariable analysis, adjusted for sex, body mass index, WHO clinical stage, time-updated CD4 count, and antiretroviral therapy status, we observed an association between cotrimoxazole and an increase in TB incidence (hazard ratio 1.7, 95% CI: 1.2, 2.2). However, when restricted to laboratory-confirmed TB, there was no association between cotrimoxazole and TB incidence (hazard ratio: 0.97, 95% CI: 0.39, 2.4). In TB cases, we found no difference in the proportion of positive sputum cultures or days to culture positivity by cotrimoxazole status. Cotrimoxazole was associated with a reduction in mortality. In this cohort with a mortality benefit from cotrimoxazole, we found an increased risk of all TB among individuals using cotrimoxazole, likely a result of residual confounding, but no association between use of cotrimoxazole and laboratory-confirmed TB. Cotrimoxazole did not compromise TB diagnosis.
    PLoS ONE 01/2014; 9(1):e83750. · 3.53 Impact Factor
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    ABSTRACT: Research in the predictors of all-cause mortality in HIV-infected people has widely been reported in literature. Making an informed decision requires understanding the methods used. We present a review on study designs, statistical methods and their appropriateness in original articles reporting on predictors of all-cause mortality in HIV-infected people between January 2002 and December 2011. Statistical methods were compared between 2002-2006 and 2007-2011. Time-to-event analysis techniques were considered appropriate. Pubmed/Medline. Original English-language articles were abstracted. Letters to the editor, editorials, reviews, systematic reviews, meta-analysis, case reports and any other ineligible articles were excluded. A total of 189 studies were identified (n = 91 in 2002-2006 and n = 98 in 2007-2011) out of which 130 (69%) were prospective and 56 (30%) were retrospective. One hundred and eighty-two (96%) studies described their sample using descriptive statistics while 32 (17%) made comparisons using t-tests. Kaplan-Meier methods for time-to-event analysis were commonly used in the earlier period (n = 69, 76% vs. n = 53, 54%, p = 0.002). Predictors of mortality in the two periods were commonly determined using Cox regression analysis (n = 67, 75% vs. n = 63, 64%, p = 0.12). Only 7 (4%) used advanced survival analysis methods of Cox regression analysis with frailty in which 6 (3%) were used in the later period. Thirty-two (17%) used logistic regression while 8 (4%) used other methods. There were significantly more articles from the first period using appropriate methods compared to the second (n = 80, 88% vs. n = 69, 70%, p-value = 0.003). Descriptive statistics and survival analysis techniques remain the most common methods of analysis in publications on predictors of all-cause mortality in HIV-infected cohorts while prospective research designs are favoured. Sophisticated techniques of time-dependent Cox regression and Cox regression with frailty are scarce. This motivates for more training in the use of advanced time-to-event methods.
    PLoS ONE 01/2014; 9(2):e87356. · 3.53 Impact Factor
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    ABSTRACT: In South Africa, the majority of tuberculosis (TB) patients are co-infected with the human immunodeficiency virus (HIV), and delays in diagnosis and treatment likely exacerbate morbidity and mortality. To determine predictors of delays in the diagnosis and treatment of hospitalised suspected pulmonary TB patients co-infected with HIV. Post-analysis of data collected in a three-centre prospective cohort of in-patients clinically diagnosed with active TB in three hospitals in South Africa between 2006 and 2009 during the first 24 h of admission. Delay was assessed by asking time of first symptoms and any prior health-seeking behaviour for this episode of illness. Data from a total of 891 participants with a median age of 36 years and a CD4 count of 67 cells/mm(3) were analysed. Median patient, system and total delays were respectively 28, 1 and 28 days. Unemployment, treatment at Tshepong Hospital, alcohol consumption, crowding index, seeking prior treatment, cotrimoxazole treatment and WHO Stage 4 disease predicted prolonged total delay. Patient delay in seeking care for TB in this high HIV prevalence setting is substantial. Factors identified with delay could be used to develop interventions to improve care seeking and earlier diagnosis of TB.
    The International Journal of Tuberculosis and Lung Disease 09/2013; 17(9):1199-205. · 2.76 Impact Factor
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    ABSTRACT: We conducted a tobacco prevalence survey among 707 in-patients diagnosed with tuberculosis (TB) at the Chris Hani Baragwanath Academic Hospital in Soweto, South Africa. Current smoking status was expanded to include both patients who self-reported at the time of TB diagnosis and patients who stopped smoking in the 2-month period before diagnosis. Six per cent reported current smoking at the time of TB diagnosis, 26% within 2 months before TB diagnosis. Human immunodeficiency virus status (73% positive) was not associated with current smoking. Classifying current smoking status among newly diagnosed TB patients should be extended to include smoking at time of the onset of TB symptoms.
    The International Journal of Tuberculosis and Lung Disease 07/2013; · 2.76 Impact Factor
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    ABSTRACT: BACKGROUND: Cost-effective and safe practices are required for the scale-up of medical male circumcision (MMC), a strategy recommended for biomedical HIV prevention. METHODS: A retrospective medical record review was conducted of post-circumcision wound infection incidence at a massive MMC program in Soweto, South Africa. We compared patients who received routine 250 mg prophylactic flucloxacillin 4 times daily orally for 5 days with those who did not receive prophylaxis. Patients with HIV infection and those with missing prophylaxis data were excluded from the analysis. Collated data included prophylaxis received, age, return for follow-up, and presence and grading of wound infection at follow-up. RESULTS: In total, 1,291 patients were eligible: 646 flucloxacillin recipients and 645 non-recipients. Median age of flucloxacillin recipients was 24 years (interquartile range 20-29 years) and for nonrecipients it was 23 years (interquartile range 16-28 years). Eighty-one percent of flucloxacillin recipients and 87% of nonrecipients (P = .0019) returned for follow-up. Wound infection was present in 0.7% (5 of 646) of flucloxacillin recipients and 1.2% (8 of 645) of non-recipients (P = .4). Use of routine prophylactic flucloxacillin did not significantly reduce incidence of post-MMC wound infection (odds ratio, 0.6; 95% confidence interval, 0-1.2). CONCLUSIONS: When compared with no prophylactic flucloxacillin, routine prophylactic flucloxacillin does not significantly reduce the risk of post-MMC wound infection in a massive circumcision program.
    American journal of infection control 03/2013; · 3.01 Impact Factor
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    ABSTRACT: OBJECTIVE:: Estimate the mortality impact of delay in antiretroviral therapy (ART) initiation from the time of entry-into-care. DESIGN:: A state-transition Markov process model. This technique allows for assessing mortality before and after ART initiation associated with delays in ART initiation among a general population of ART eligible patients without conducting a randomized trial. METHODS:: We used patient-level data from three South African cohorts to determine transition probabilities for pre-ART CD4 count changes and pre-ART and on-ART mortality. For each parameter we generated probabilities and distributions for Monte Carlo simulations with one week cycles to estimate mortality 52 weeks from clinic entry. RESULTS:: We estimated an increase in mortality from 11.0% to 14.7% (relative increase of 34%) with a 10 week delay in ART for patients entering care with our pre-ART cohort CD4 distribution. When we examined low CD4 ranges, the relative increase in mortality delays remained similar; however, the absolute increase in mortality rose. For example, among patients entering with CD4 count 50-99 cells/mm, 12 month mortality increased from 13.3% with no delay compared to 17.0% with a 10 week delay and 22.9% with a 6 month delay. CONCLUSIONS:: Delays in ART initiation, common in routine HIV programs, can lead to important increases in mortality. Prompt ART initiation for patients entering clinical care and eligible for ART, especially those with lower CD4 counts, could be a relatively low cost approach with a potential marked impact on mortality.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 02/2013; · 4.65 Impact Factor
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    ABSTRACT: Symptom screening is a recommended component of intensified case-finding (ICF) for pulmonary tuberculosis (TB) among HIV-infected individuals. Symptomatic individuals are further investigated to either exclude or diagnose pulmonary TB, thus reducing the number of individuals requiring costly laboratory investigation. Those with laboratory evaluations negative for pulmonary TB or who lack symptoms may be eligible for antiretroviral therapy (ART) and/or TB isoniazid preventive therapy (IPT). A four-part symptom screen has been recommended by the World Health Organization (WHO) for identifying TB suspects and those unlikely to have TB. A meta-analysis of studies among HIV-infected individuals calculated a sensitivity of 90.1% for the four-part symptoms screen - of any of cough, fever, night sweats, or weight loss - among patients in clinical care, making it an effective tool for identifying most patients with TB. An important population for intensified case-finding not included in that meta-analysis was HIV-infected pregnant women. We undertook a cross-sectional survey among HIV-infected pregnant women receiving prenatal care at community clinics in South Africa. We obtained a four-symptom review and sputum smear microscopy and mycobacterial culture on all participants. Among 1415 women, 226 (16%) had a positive symptom screen, and 35 (2.5%) were newly diagnosed with culture-positive TB. Twelve were on TB treatment at the time of screening, yielding 47 (3.3%) women with prevalent TB. Symptom screening among women without known TB had a sensitivity of 28% and specificity of 84%. The poor performance of symptom screening to identify women with TB suggests that other approaches may be needed for intensified case-finding to be effective for this population.
    PLoS ONE 01/2013; 8(4):e62211. · 3.53 Impact Factor
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    ABSTRACT: Objective: Cervical cancer is a leading cause of cancer mortality in South Africa. However, little is known about oral human papillomavirus (HPV) infection in high human immunodeficiency virus (HIV) seroprevalence settings. Method: Thirty-four adult heterosexual couples attending an HIV testing center in Soweto, South Africa were enrolled. Each participant provided an oral rinse sample and genital swab, which were tested for 37 types of HPV DNA, and completed a risk behavior survey. Results: Median age was 31 years and 9% (3/34) of men and 29% (10/34) of women enrolled tested HIV-positive; median CD4 count was 437 cells/mm(3). Oral HPV prevalence was similar in women and men (12 vs. 18%, p = 0.48), and was non-significantly higher in HIV-infected vs. HIV-uninfected (23 vs. 13%, p = 0.34) subjects. Most men (82%) and women (84%) reported ever performing oral sex. Median number of lifetime sexual partners was "2-5" while median number of lifetime oral sex partners was 1. Oncogenic HPV subtypes were detected in 4% of oral, 26% of penile, and 74% of vaginal samples, including HPV16 in 1, 12, and 21% of these samples respectively. Genital HPV prevalence was significantly higher than oral HPV prevalence (75 vs. 15%, p ≤ 0.001). Thirty-five percent of couples (12/34) had at least one type-specific concordant vaginal-penile HPV infection but only one of nine couples with oral HPV had concordant oral-oral infection. However, 67% (4/6) of men and 25% (1/4) of women with oral HPV infection had partners with concordant genital HPV infection. Implications and Impact: Oral-oral HPV concordance between couples is low, but oral-genital and genital-genital HPV concordance is higher, including concordance of male oral HPV infection with their partners' vaginal HPV infection. This data is consistent with possible transmission of vaginal HPV infection to the oral cavity of sexual partners performing oral sex.
    Frontiers in Oncology 01/2013; 3:303.
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    ABSTRACT: Few studies have compared hospitalisations before and after antiretroviral therapy (ART) initiation in the same patients. We analysed the cost of hospitalisations among 3,906 adult patients in two South African hospitals, 30% of whom initiated ART. Hospitalisations were 50% and 40% more frequent and 1.5 and 2.6 times more costly at a CD4 cell count <100 cells/mm when compared to 200-350 cells/mm in the pre-ART and ART period, respectively. Mean inpatient cost per patient year was USD 117 (95% confidence interval, CI, 85-158) for patients on ART and USD 72 (95% CI, 56-89) for pre-ART patients. Raising ART eligibility thresholds could avoid the high cost of hospitalisation before and immediately after ART initiation.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 11/2012; · 4.65 Impact Factor
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    ABSTRACT: BACKGROUND: In South Africa, patients with multi-drug-resistant tuberculosis (MDR-TB) are hospitalised from MDR-TB treatment initiation until culture conversion. Although MDR-TB accounts for <3% of incident TB in South Africa, 55% of the public sector TB budget is spent on MDR-TB. To inform new strategies for MDR-TB management, we estimated the per-patient cost (USD 2011) of inpatient MDR-TB treatment. METHODS: All resources used by patients admitted to the MDR-TB hospital with confirmed MDR-TB from March 2009 to February 2010 were abstracted from patient records for up to 12 months after initial admission or until the earliest of final discharge, abscondment or death. Costs of hospital stay/day were estimated from hospital expenditure records and costs for drugs, laboratory tests, radiography and surgery from public sector sources. 133 patients met study inclusion criteria of whom 121 had complete cost records. RESULTS: By 12 months, 86% were discharged with culture conversion, 8% died in hospital, 2% were still admitted, and 3% had absconded. The mean hospital stay was 105 days. The mean total cost per patient was $17 164, of which 95% were hospitalisation costs (buildings, staff, etc.) and ≤ 2% each for MDR-TB drugs ($380); TB laboratory tests, including drug susceptibility testing ($236); and other costs. CONCLUSIONS: The inpatient cost per patient treated for MDR-TB is more than 40 times the cost of treating drug-susceptible TB in South Africa. There is potential for substantial cost savings from improved management of drug-susceptible TB and shifting to a model of decentralised, outpatient MDR-treatment.
    Tropical Medicine & International Health 11/2012; · 2.94 Impact Factor

Publication Stats

1k Citations
503.31 Total Impact Points

Institutions

  • 2006–2014
    • University of the Witwatersrand
      • • Perinatal HIV Research Unit
      • • Division of Anatomical Pathology
      • • School of Public Health
      • • School of Electrical and Information Engineering
      Johannesburg, Gauteng, South Africa
  • 2007–2013
    • Johns Hopkins University
      • • Center for Tuberculosis Research
      • • Department of Medicine
      Baltimore, Maryland, United States
  • 2012
    • University of KwaZulu-Natal
      • Centre for the AIDS Programme of Research in South Africa (CAPRISA)
      Durban, KwaZulu-Natal, South Africa
  • 2010–2012
    • Johns Hopkins Bloomberg School of Public Health
      • Department of Health Policy and Management
      Baltimore, MD, United States
  • 2011
    • University of Rochester
      • Department of Community and Preventive Medicine
      Rochester, NY, United States
    • National University of Singapore
      • Department of Statistics and Applied Probability
      Singapore, Singapore
  • 2010–2011
    • Brown University
      • Alpert Medical School
      Providence, RI, United States
  • 2008
    • University of California, San Francisco
      San Francisco, California, United States
    • Chris Hani Baragwanath Hospital
      Johannesburg, Gauteng, South Africa
    • Alpert Medical School - Brown University
      Providence, Rhode Island, United States