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Dive into the research topics where Hans Prozesky is active.

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Featured researches published by Hans Prozesky.


PLOS Medicine | 2013

Life Expectancies of South African Adults Starting Antiretroviral Treatment: Collaborative Analysis of Cohort Studies

Leigh F. Johnson; Joël Mossong; Rob Dorrington; Michael Schomaker; Christopher J. Hoffmann; Olivia Keiser; Matthew P. Fox; Robin Wood; Hans Prozesky; Janet Giddy; Daniela Garone; Morna Cornell; Matthias Egger; Andrew Boulle

Leigh Johnson and colleagues estimate the life expectancies of HIV positive South African adults who are taking antiretroviral therapy by using information from 6 programmes between 2001 and 2010.


AIDS | 2010

Temporal changes in programme outcomes among adult patients initiating antiretroviral therapy across South Africa, 2002-2007

Morna Cornell; Anna Grimsrud; Lara Fairall; Matthew P. Fox; Gilles van Cutsem; Janet Giddy; Robin Wood; Hans Prozesky; Lerato Mohapi; Claire Graber; Matthias Egger; Andrew Boulle; Landon Myer

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.


BMC Public Health | 2007

Gender distribution of adult patients on highly active antiretroviral therapy (HAART) in Southern Africa: a systematic review

Adamson S. Muula; Thabale Ngulube; Seter Siziya; Cecilia Makupe; Eric Umar; Hans Prozesky; Charles Shey Wiysonge; Ronald Mataya

BackgroundHIV and AIDS are significant and growing public health concerns in southern Africa. The majority of countries in the region have national adult HIV prevalence estimates exceeding 10 percent. The increasing availability of highly active antiretroviral therapy (HAART) has potential to mitigate the situation. There is however concern that women may experience more barriers in accessing treatment programs than men.MethodsA systematic review of the literature was carried out to describe the gender distribution of patients accessing highly active antiretroviral therapy (HAART) in Southern Africa. Data on number of patients on treatment, their mean or median age and gender were obtained and compared across studies and reports.ResultsThe median or mean age of patients in the studies ranged from 33 to 39 years. While female to male HIV infection prevalence ratios in the southern African countries ranged from 1.2:1 to 1.6:1, female to male ratios on HAART ranged from 0.8: 1 to 2.3: 1. The majority of the reports had female: male ratio in treatment exceeding 1.6. Overall, there were more females on HAART than there were males and this was not solely explained by the higher HIV prevalence among females compared to males.ConclusionIn most Southern African countries, proportionally more females are on HIV antiretroviral treatment than men, even when the higher HIV infection prevalence in females is accounted for. There is need to identify the factors that are facilitating womens accessibility to HIV treatment. As more patients access HAART in the region, it will be important to continue assessing the gender distribution of patients on HAART.


PLOS Medicine | 2012

Gender differences in survival among adult patients starting antiretroviral therapy in South Africa: a multicentre cohort study.

Morna Cornell; Michael Schomaker; Daniela Garone; Janet Giddy; Christopher J. Hoffmann; Richard J Lessells; Mhairi Maskew; Hans Prozesky; Robin Wood; Leigh F. Johnson; Matthias Egger; Andrew Boulle; Landon Myer

Morna Cornell and colleagues investigate differences in mortality for HIV-positive men and women on antiretroviral therapy in South Africa.


AIDS | 2011

Outcomes of Antiretroviral Treatment in Programmes with and without Routine Viral Load Monitoring in Southern Africa

Olivia Keiser; Benjamin H. Chi; Thomas Gsponer; Andrew Boulle; Catherine Orrell; Sam Phiri; Nicola Maxwell; Mhairi Maskew; Hans Prozesky; Matthew P. Fox; Andrew O. Westfall; Matthias Egger

Objectives:To compare outcomes of antiretroviral therapy (ART) in South Africa, where viral load monitoring is routine, with those in Malawi and Zambia, where monitoring is based on CD4 cell counts. Methods:We included 18 706 adult patients starting ART in South Africa and 80 937 patients in Zambia or Malawi. We examined CD4 responses in models for repeated measures and the probability of switching to second-line regimens, mortality and loss to follow-up in multistate models, measuring time from 6 months. Results:In South Africa, 9.8% [95% confidence interval (CI) 9.1–10.5] had switched at 3 years, 1.3% (95% CI 0.9–1.6) remained on failing first-line regimens, 9.2% (95% CI 8.5–9.8) were lost to follow-up and 4.3% (95% CI 3.9–4.8) had died. In Malawi and Zambia, more patients were on a failing first-line regimen [3.7% (95% CI 3.6–3.9], fewer patients had switched [2.1% (95% CI 2.0–2.3)] and more patients were lost to follow-up [15.3% (95% CI 15.0–15.6)] or had died [6.3% (95% CI 6.0–6.5)]. Median CD4 cell counts were lower in South Africa at the start of ART (93 vs. 132 cells/&mgr;l; P < 0.001) but higher after 3 years (425 vs. 383 cells/&mgr;l; P < 0.001). The hazard ratio comparing South Africa with Malawi and Zambia after adjusting for age, sex, first-line regimen and CD4 cell count was 0.58 (0.50–0.66) for death and 0.53 (0.48–0.58) for loss to follow-up. Conclusion:Over 3 years of ART mortality was lower in South Africa than in Malawi or Zambia. The more favourable outcome in South Africa might be explained by viral load monitoring leading to earlier detection of treatment failure, adherence counselling and timelier switching to second-line ART.


Journal of Acquired Immune Deficiency Syndromes | 2010

Early mortality and loss to follow-up in HIV-infected children starting antiretroviral therapy in Southern Africa

Lukas Fenner; Martin W. G. Brinkhof; Olivia Keiser; Ralf Weigel; Morna Cornell; Harry Moultrie; Hans Prozesky; Karl Technau; Brian Eley; Paula Vaz; Margaret Pascoe; Janet Giddy; Gilles van Cutsem; Robin Wood; Matthias Egger; Mary-Ann Davies

Background:Many HIV-infected children in Southern Africa have been started on antiretroviral therapy (ART), but loss to follow up (LTFU) can be substantial. We analyzed mortality in children retained in care and in all children starting ART, taking LTFU into account. Patients and Methods:Children who started ART before the age of 16 years in 10 ART programs in South Africa, Malawi, Mozambique, and Zimbabwe were included. Risk factors for death in the first year of ART were identified in Weibull models. A meta-analytic approach was used to estimate cumulative mortality at 1 year. Results:Eight thousand two hundred twenty-five children (median age 49 months, median CD4 cell percent 11.6%) were included; 391 (4.8%) died and 523 (7.0%) were LTFU in the first year. Mortality at 1 year was 4.5% [95% confidence interval (CI): 2.8% to 7.4%] in children remaining in care, but 8.7% (5.4% to 12.1%) at the program level, after taking mortality in children and LTFU into account. Factors associated with mortality in children remaining in care included age [adjusted hazard ratio (HR) 0.37; 95% CI: 0.25 to 0.54 comparing ≥120 months with <18 months], CD4 cell percent (HR: 0.56; 95% CI: 0.39 to 0.78 comparing ≥20% with <10%), and clinical stage (HR: 0.12; 95% CI: 0.03 to 0.45 comparing World Health Organization stage I with III/IV). Conclusions:In children starting ART and remaining in care in Southern Africa mortality at 1 year is <5% but almost twice as high at the program level, when taking LTFU into account. Age, CD4 percentage, and clinical stage are important predictors of mortality at the individual level.


Journal of Acquired Immune Deficiency Syndromes | 2012

Rates and Predictors of Failure of First-line Antiretroviral Therapy and Switch to Second-line ART in South Africa

Matthew P. Fox; Gilles van Cutsem; Janet Giddy; Mhairi Maskew; Olivia Keiser; Hans Prozesky; Robin Wood; Miguel A. Hernán; Jonathan A C Sterne; Matthias Egger; Andrew Boulle

Objectives: To measure rates and predictors of virologic failure and switch to second-line antiretroviral therapy (ART) in South Africa. Design: Observational cohort study. Methods: We included ART-naive adult patients initiated on public sector ART (January 2000 to July 2008) at 5 sites in South Africa who completed ≥6 months of follow-up. We estimated cumulative risk of virologic failure (viral load ≥400 copies/mL with confirmation above varying thresholds) and switching to second-line ART. Results: Nineteen thousand six hundred forty-five patients (29,935 person-years) had a median of 1.3 years of study follow-up (1.8 years on ART) and a median CD4 count of 93 (IQR: 39–155) cells per microliter at ART initiation. About 9.9% (4.5 per 100 person-years) failed ART in median 16 (IQR: 12–23) months since ART initiation, with median 2.7 months (IQR: 1.6–4.7) months between first elevated and confirmatory viral loads. By survival analysis, using a confirmatory threshold of 400 copies per milliliter, 16.9% [95% confidence interval (CI): 15.4% to 18.6%] failed by 5 years on ART, but only 7.8% (95% CI: 6.6% to 9.3%) using a threshold of 10,000. CD4 <25 versus 100–199 (adjusted HR: 1.60; 95% CI: 1.37 to 1.87), ART initiation viral load ≥1,000,000 versus <10,000, (1.32; 0.91 to 1.93), and 2+ gaps in care versus 0 (95% CI: 7.25; 4.95 to 10.6) were predictive of failure. Overall, 10.1% (95% CI: 9.0% to 11.4%) switched to second-line by 5 years on ART. Lower CD4 at failure and higher rate of CD4 decline were predictive of switch (decline 100% to 51% versus 25% to –25%, adjusted HR: 1.96; 95% CI: 1.35 to 2.85). Conclusions: In resource-limited settings with viral load monitoring, virologic failure rates are highly sensitive to thresholds for confirmation. Despite clear guidelines there is considerable variability in switching failing patients, partially in response to immunologic status and postfailure evolution.


The New England Journal of Medicine | 2013

A dimorphic fungus causing disseminated infection in South Africa.

Chris Kenyon; Kim Bonorchis; Craig Corcoran; Graeme Meintjes; Michael Locketz; Hester F. Vismer; Preneshni Naicker; Hans Prozesky; Marelize Van Wyk; Colleen Bamford; Gail Imrie; Sipho Dlamini; Andrew M. Borman; Robert Colebunders; Cedric P. Yansouni; Marc Mendelson; Nelesh P. Govender

BACKGROUND The genus emmonsia contains three species that are associated with human disease. Emmonsia crescens and Emmonsia parva are the agents that cause adiaspiromycosis, and one human case of Emmonsia pasteuriana infection has been described. We report a fungal pathogen within the genus emmonsia that is most closely related to E. pasteuriana in human immunodeficiency virus (HIV)-infected adults in South Africa. METHODS Between July 2008 and July 2011, we conducted enhanced surveillance to identify the cause of systemic, dimorphic fungal infections in patients presenting to Groote Schuur Hospital and other hospitals affiliated with the University of Cape Town, Cape Town, South Africa. DNA sequencing was used to identify pathogenic fungi. RESULTS A total of 24 cases of dimorphic fungal infection were diagnosed, 13 of which were caused by an emmonsia species. All 13 patients were HIV-infected, with a median CD4+ T-cell count of 16 cells per cubic millimeter (interquartile range, 10 to 44), and all had evidence of disseminated fungal disease. Three patients died soon after presentation, but the others had a good response to a variety of antifungal agents and antiretroviral therapy. Phylogenetic analysis of five genes (LSU, ITS1-2, and the genes encoding actin, β-tubulin, and intein PRP8) revealed that this fungus belongs in the genus emmonsia and is most closely related to E. pasteuriana. CONCLUSIONS The findings suggest that these isolates of an emmonsia species represent a new species of dimorphic fungus that is pathogenic to humans. The species appears to be an important cause of infections in Cape Town.


Journal of Acquired Immune Deficiency Syndromes | 2013

Immunodeficiency at the start of combination antiretroviral therapy in low-, middle- and high-income countries

Dorita Avila; Keri N. Althoff; Catrina Mugglin; Kara Wools-Kaloustian; Manuel Koller; François Dabis; Denis Nash; Thomas Gsponer; Somnuek Sungkanuparph; Catherine C. McGowan; Margaret T May; David A. Cooper; Cleophas Chimbetete; Marcelo Wolff; Ann C. Collier; Hamish McManus; Mary-Ann Davies; Dominique Costagliola; Crabtree-Ramirez B; Romanee Chaiwarith; Angela Cescon; Morna Cornell; Lameck Diero; Praphan Phanuphak; Adrien Sawadogo; Jochen Ehmer; Serge P Eholie; Patrick Ck Li; Matthew P. Fox; Neel R. Gandhi

Objective:To describe the CD4 cell count at the start of combination antiretroviral therapy (cART) in low-income (LIC), lower middle-income (LMIC), upper middle-income (UMIC), and high-income (HIC) countries. Methods:Patients aged 16 years or older starting cART in a clinic participating in a multicohort collaboration spanning 6 continents (International epidemiological Databases to Evaluate AIDS and ART Cohort Collaboration) were eligible. Multilevel linear regression models were adjusted for age, gender, and calendar year; missing CD4 counts were imputed. Results:In total, 379,865 patients from 9 LIC, 4 LMIC, 4 UMIC, and 6 HIC were included. In LIC, the median CD4 cell count at cART initiation increased by 83% from 80 to 145 cells/&mgr;L between 2002 and 2009. Corresponding increases in LMIC, UMIC, and HIC were from 87 to 155 cells/&mgr;L (76% increase), 88 to 135 cells/&mgr;L (53%), and 209 to 274 cells/&mgr;L (31%). In 2009, compared with LIC, median counts were 13 cells/&mgr;L [95% confidence interval (CI): −56 to +30] lower in LMIC, 22 cells/&mgr;L (−62 to +18) lower in UMIC, and 112 cells/&mgr;L (+75 to +149) higher in HIC. They were 23 cells/&mgr;L (95% CI: +18 to +28 cells/&mgr;L) higher in women than men. Median counts were 88 cells/&mgr;L (95% CI: +35 to +141 cells/&mgr;L) higher in countries with an estimated national cART coverage >80%, compared with countries with <40% coverage. Conclusions:Median CD4 cell counts at the start of cART increased 2000–2009 but remained below 200 cells/&mgr;L in LIC and MIC and below 300 cells/&mgr;L in HIC. Earlier start of cART will require substantial efforts and resources globally.


South African Medical Journal | 2009

Monitoring the South African National Antiretroviral Treatment Programme, 2003 – 2007: The IeDEA Southern Africa Collaboration

Morna Cornell; Karl Technau; Lara Fairall; Robin Wood; Harry Moultrie; Gilles van Cutsem; Janet Giddy; Lerato Mohapi; Brian Eley; Patrick MacPhail; Hans Prozesky; Helena Rabie; Mary-Ann Davies; Nicola Maxwell; Andrew Boulle

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.

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Robin Wood

University of Cape Town

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Mhairi Maskew

University of the Witwatersrand

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Christopher J. Hoffmann

Johns Hopkins University School of Medicine

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Daniela Garone

Médecins Sans Frontières

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