Browsing by Author "Hermans, Sabine"

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    Open Access
    A century of tuberculosis epidemiology in the northern and southern hemisphere: the differential impact of control interventions
    (Public Library of Science, 2015) Hermans, Sabine; Jr, C Robert Horsburgh; Wood, Robin
    BACKGROUND: Cape Town has one of the highest TB burdens of any city in the world. In 1900 the City of Cape Town, New York City and London had high mortality of tuberculosis (TB). Throughout the 20th century contemporaneous public health measures including screening, diagnosis and treatment were implemented in all three settings. Mandatory notification of TB and vital status enabled comparison of disease burden trajectories. METHODS: TB mortality, notification and case fatality rates were calculated from 1912 to 2012 using annual TB notifications, TB death certifications and population estimates. Notification rates were stratified by age and in Cape Town by HIV status (from 2009 onwards). RESULTS: Pre-chemotherapy, TB mortality and notification rates declined steadily in New York and London but remained high in Cape Town. Following introduction of combination chemotherapy, mean annual case fatality dropped from 45-60% to below 10% in all three settings. Mortality and notification rates subsequently declined, although Cape Town notifications did not decline as far as those in New York or London and returned to pre-chemotherapy levels by 1980. The proportional contribution of childhood TB diminished in New York and London but remained high in Cape Town. The advent of the Cape Town HIV-epidemic in the 1990s was associated with a further two-fold increase in incidence. In 2012, notification rates among HIV-negatives remained at pre-chemotherapy levels. CONCLUSIONS: TB control was achieved in New York and London but failed in Cape Town. The TB disease burden trajectories started diverging before the availability of combination chemotherapy in 1952 and further diverged following the HIV epidemic in 1990. Chemotherapy impacted case fatality but not transmission, evidenced by on-going high childhood TB rates. Currently endemic TB results from high on-going transmission, which has been exacerbated by the HIV epidemic. TB control will require reducing transmission, which is inexorably linked to prevailing socio-economic factors.
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    HIV and TB co-infection in the ART era: CD4 count distributions and TB case fatality in Cape Town
    (BioMed Central, 2018-07-31) Kaplan, Richard; Hermans, Sabine; Caldwell, Judy; Jennings, Karen; Bekker, Linda-Gail; Wood, Robin
    Background In Cape Town, the roll-out of antiretroviral therapy (ART) has increased over the last decade with an estimated coverage of 63% of HIV- positive patients in 2013. The influence of ART on the characteristics of the population of HIV-positive patients presenting to the primary care TB programme is unknown. In this study, we examined trends in CD4 count distribution, ART usage and treatment outcomes among HIV-positive TB patients in Cape Town from 2009 to 2013. Methods Data from the electronic TB register on all newly registered drug-sensitive TB patients ≥18 years were analyzed retrospectively. Descriptive statistics were used to compare baseline characteristics, the CD4 count distribution and TB treatment outcomes both by year of treatment and ART status at the start of TB treatment. Survival analyses were used to assess the change in mortality risk during TB treatment over time, stratified by ART status at start of TB treatment. Results 118,989 patients were treated over 5 years. HIV prevalence among TB patients decreased from 50.9% in 2009 to 49.0% in 2013. The absolute number of HIV-positive TB cases declined by 13.2% between 2010 and 2013. More patients entered the TB programme on ART in 2013 compared to 2009 (30.0% vs 9.9%). Among these, the CD4 count distribution showed a year by year shift to higher CD4 counts. In 2013, over 75% of ART-naïve TB patients still had a CD4 count < 350 cells/mm3. ART initiation among ART-naive patients increased from 37.0 to 77.7% and TB case fatality declined from 7.4 to 5.2% (p < 0.001). In multivariate analysis a decrease in TB mortality was most strongly associated with CD4 count (Adjusted HR 0.82 per increase of 50 cells/mm3, 95% CI: 0.81–0.83, p < 001) and the initiation of ART during TB treatment (Adjusted HR 0.39, 95% CI: 0.35–0.42, p < 0.001). Conclusion Comprehensive changes in the ART and TB treatment programmes resulted in incremental increases in ART coverage for HIV-positive TB patients and a subsequent decrease in TB case fatality due to increased ART uptake in HIV-positive ART-naïve patients. However TB still remained a major presenting opportunistic infection with the majority of cases occurring at low CD4 counts.
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    Impact of Anti-Retroviral Treatment and Cotrimoxazole Prophylaxis on Helminth Infections in HIV-Infected Patients in Lambar�n�, Gabon
    (Public Library of Science, 2015) Janssen, Saskia; Hermans, Sabine; Knap, Martijn; Moekotte, Alma; Rossatanga, Elie G; Adegnika, Akim A; Bélard, Sabine; Hänscheid, Thomas; Grobusch, Martin P
    Background: Foci of the HIV epidemic and helminthic infections largely overlap geographically. Treatment options for helminth infections are limited, and there is a paucity of drug-development research in this area. Limited evidence suggests that antiretroviral therapy (ART) reduces prevalence of helminth infections in HIV-infected individuals. We investigated whether ART exposure and cotrimoxazole preventive therapy (CTX-P) is associated with a reduced prevalence of helminth infections. Methodology and Principal Findings: This cross-sectional study was conducted at a primary HIV-clinic in Lambaréné, Gabon. HIV-infected adults who were ART-naïve or exposed to ART for at least 3 months submitted one blood sample and stool and urine samples on 3 consecutive days. Outcome was helminth infection with intestinal helminths, Schistosoma haematobium, Loa loa or Mansonella perstans. Multivariable logistic regression was used to assess associations between ART or CTX-P and helminth infection. In total, 408 patients were enrolled. Helminth infection was common (77/252 [30.5%]). Filarial infections were most prevalent (55/310 [17.7%]), followed by infection with intestinal helminths (35/296 [11.8%]) and S. haematobium (19/323 [5.9%]). Patients on CTX-P had a reduced risk of Loa loa microfilaremia (adjusted odds ratio (aOR) 0.47, 95% CI 0.23-0.97, P = 0.04), also in the subgroup of patients on ART (aOR 0.36, 95% CI 0.13-0.96, P = 0.04). There was no effect of ART exposure on helminth infection prevalence. Conclusions/Significance: CTX-P use was associated with a decreased risk of Loa loa infection, suggesting an anthelminthic effect of antifolate drugs. No relation between ART use and helminth infections was established.