Andreas D Haas
University of Bern
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Featured researches published by Andreas D Haas.
AIDS | 2014
Lyson Tenthani; Andreas D Haas; Hannock Tweya; Andreas Jahn; Joep J. van Oosterhout; Frank Chimbwandira; Zengani Chirwa; Wingston Ng’ambi; Alan Bakali; Sam Phiri; Landon Myer; Fabio Valeri; Marcel Zwahlen; Gilles Wandeler; Olivia Keiser
Objective:To explore the levels and determinants of loss to follow-up (LTF) under universal lifelong antiretroviral therapy (ART) for pregnant and breastfeeding women (‘Option B+’) in Malawi. Design, setting, and participants:We examined retention in care, from the date of ART initiation up to 6 months, for women in the Option B+ program. We analysed nationwide facility-level data on women who started ART at 540 facilities (n = 21 939), as well as individual-level data on patients who started ART at 19 large facilities (n = 11 534). Results:Of the women who started ART under Option B+ (n = 21 939), 17% appeared to be lost to follow-up 6 months after ART initiation. Most losses occurred in the first 3 months of therapy. Option B+ patients who started therapy during pregnancy were five times more likely than women who started ART in WHO stage 3/4 or with a CD4+ cell count 350 cells/&mgr;l or less, to never return after their initial clinic visit [odds ratio (OR) 5.0, 95% confidence interval (CI) 4.2–6.1]. Option B+ patients who started therapy while breastfeeding were twice as likely to miss their first follow-up visit (OR 2.2, 95% CI 1.8–2.8). LTF was highest in pregnant Option B+ patients who began ART at large clinics on the day they were diagnosed with HIV. LTF varied considerably between facilities, ranging from 0 to 58%. Conclusion:Decreasing LTF will improve the effectiveness of the Option B+ approach. Tailored interventions, like community or family-based models of care could improve its effectiveness.
The Lancet HIV | 2016
Andreas D Haas; Lyson Tenthani; Malango T Msukwa; Kali Tal; Andreas Jahn; Oliver Jintha Gadabu; Adrian Spoerri; Frank Chimbwandira; Joep J. van Oosterhout; Olivia Keiser
BACKGROUND Studies of Malawis option B+ programme for HIV-positive pregnant and breastfeeding women have reported high loss to follow-up during pregnancy and at the start of antiretroviral therapy (ART), but few data exist about retention during breastfeeding and after weaning. We examined loss to follow-up and retention in care in patients in the option B+ programme during their first 3 years on ART. METHODS We analysed two data sources: aggregated facility-level data about patients in option B+ who started ART between Oct 1, 2011, and June 30, 2012, at 546 health facilities; and patient-level data from 20 large facilities with electronic medical record system for HIV-positive women who started ART between Sept 1, 2011, and Dec 31, 2013, under option B+ or because they had WHO clinical stages 3 or 4 disease or had CD4 counts of less than 350 cells per μL. We used facility-level data to calculate representative estimates of retention and loss to follow-up. We used patient-level data to study temporal trends in retention, timing of loss to follow-up, and predictors of no follow-up and loss to follow-up. We defined patients who were more than 60 days late for their first follow-up visit as having no follow-up and patients who were more than 60 days late for a subsequent visit as being lost to follow-up. We calculated proportions and cumulative probabilities of patients who had died, stopped ART, had no follow-up, were lost to follow-up, or were retained alive on ART for 36 months. We calculated odds ratios and hazard ratios to examine predictors of no follow-up and loss to follow-up. FINDINGS Analysis of facility-level data about patients in option B+ who had not transferred to a different facility showed retention in care to be 76·8% (20 475 of 26,658 patients) after 12 months, 70·8% (18,306 of 25,849 patients) after 24 months, and 69·7% (17,787 of 25,535 patients) after 36 months. Patient-level data included 29,145 patients. 14,630 (50·2%) began treatment under option B+. Patients in option B+ had a higher risk of having no follow-up and, for the first 2 years of ART, higher risk of loss to follow-up than did patients who started ART because they had CD4 counts less than 350 cells per μL or WHO clinical stage 3 or 4 disease. Risk of loss to follow-up during the third year was low and similar for patients retained for 2 years. Retention rates did not change as the option B+ programme matured. INTERPRETATION Our data suggest that pregnant and breastfeeding women who start ART immediately after they are diagnosed with HIV can be retained on ART through the option B+ programme, even after many have stopped breastfeeding. Interventions might be needed to improve retention in the first year on ART in option B+. FUNDING Bill & Melinda Gates Foundation, Partnerships for Enhanced Engagement in Research Health, and National Institute of Allergy and Infectious Diseases.
Clinical Infectious Diseases | 2016
Andreas D Haas; Malango T Msukwa; Matthias Egger; Lyson Tenthani; Hannock Tweya; Andreas Jahn; Oliver Jintha Gadabu; Kali Tal; Luisa Salazar-Vizcaya; Janne Estill; Adrian Spoerri; Nozgechi Phiri; Frank Chimbwandira; Joep J. van Oosterhout; Olivia Keiser
One-third of women enrolled in Malawis program to prevent human immunodeficiency virus mother-to-child-transmission (Option B+) adhered inadequately to antiretroviral therapy during pregnancy and breastfeeding. Long-term virological outcomes must be closely monitored, and effective interventions to improve adherence should be deployed.
The Lancet HIV | 2015
Andreas D Haas; Olivia Keiser; Eric Balestre; Steve Brown; Emmanuel Bissagnene; Cleophas Chimbetete; François Dabis; Mary-Ann Davies; Christopher J. Hoffmann; Patrick Oyaro; Rosalind Parkes-Ratanshi; Steven J. Reynolds; Izukanji Sikazwe; Kara Wools-Kaloustian; D Marcel Zannou; Gilles Wandeler; Matthias Egger
BACKGROUND HIV-1 viral load (VL) testing is recommended to monitor antiretroviral therapy (ART) but not universally available. We examined monitoring of first-line and switching to second-line ART in sub-Saharan Africa, 2004-2013. METHODS Adult HIV-1 infected patients starting combination ART in 16 countries were included. Switching was defined as a change from a non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen to a protease inhibitor (PI)-based regimen, with a change of ≥1 NRTI. Virological and immunological failures were defined per World Health Organization criteria. We calculated cumulative probabilities of switching and hazard ratios with 95% confidence intervals (CI) comparing routine VL monitoring, targeted VL monitoring, CD4 cell monitoring and clinical monitoring, adjusted for programme and individual characteristics. FINDINGS Of 297,825 eligible patients, 10,352 patients (3·5%) switched during 782,412 person-years of follow-up. Compared to CD4 monitoring hazard ratios for switching were 3·15 (95% CI 2·92-3·40) for routine VL, 1·21 (1·13-1·30) for targeted VL and 0·49 (0·43-0·56) for clinical monitoring. Overall 58.0% of patients with confirmed virological and 19·3% of patients with confirmed immunological failure switched within 2 years. Among patients who switched the percentage with evidence of treatment failure based on a single CD4 or VL measurement ranged from 32·1% with clinical to 84.3% with targeted VL monitoring. Median CD4 counts at switching were 215 cells/µl under routine VL monitoring but lower with other monitoring (114-133 cells/µl). INTERPRETATION Overall few patients switched to second-line ART and switching occurred late in the absence of routine viral load monitoring. Switching was more common and occurred earlier with targeted or routine viral load testing.BACKGROUND HIV-1 viral load testing is recommended to monitor antiretroviral therapy (ART) but is not universally available. The aim of our study was to assess monitoring of first-line ART and switching to second-line ART in sub-Saharan Africa. METHODS We did a collaborative analysis of cohort studies from 16 countries in east Africa, southern Africa, and west Africa that participate in the international epidemiological database to evaluate AIDS (IeDEA). We included adults infected with HIV-1 who started combination ART between January, 2004, and January, 2013. We defined switching of ART as a change from a non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen to one including a protease inhibitor, with adjustment of one or more nucleoside reverse-transcriptase inhibitors (NRTIs). Virological and immunological failures were defined according to WHO criteria. We calculated cumulative probabilities of switching and hazard ratios with 95% CIs comparing routine viral load monitoring, targeted viral load monitoring, CD4 monitoring, and clinical monitoring, adjusting for programme and individual characteristics. FINDINGS Of 297,825 eligible patients, 10,352 (3%) switched to second-line ART during 782 ,412 person-years of follow-up. Compared with CD4 monitoring, hazard ratios for switching were 3·15 (95% CI 2·92-3·40) for routine viral load monitoring, 1·21 (1·13-1·30) for targeted viral load monitoring, and 0·49 (0·43-0·56) for clinical monitoring. Of 6450 patients with confirmed virological failure, 58·0% (95% CI 56·5-59·6) switched by 2 years, and of 15,892 patients with confirmed immunological failure, 19·3% (18·5-20·0) switched by 2 years. Of 10,352 patients who switched, evidence of treatment failure based on one CD4 count or viral load measurement ranged from 86 (32%) of 268 patients with clinical monitoring to 3754 (84%) of 4452 with targeted viral load monitoring. Median CD4 counts at switching were 215 cells per μL (IQR 117-335) with routine viral load monitoring, but were lower with other types of monitoring (range 114-133 cells per μL). INTERPRETATION Overall, few patients switched to second-line ART and switching happened late in the absence of routine viral load monitoring. Switching was more common and happened earlier after initiation of ART with targeted or routine viral load testing. FUNDING National Institute of Allergy and Infectious Diseases, Swiss National Science Foundation.
The Lancet HIV | 2015
Andreas D Haas; Olivia Keiser; Eric Balestre; Steve Brown; Emmanuel Bissagnene; Cleophas Chimbetete; François Dabis; Mary-Ann Davies; Christopher J. Hoffmann; Patrick Oyaro; Rosalind Parkes-Ratanshi; Steven J. Reynolds; Izukanji Sikazwe; Kara Wools-Kaloustian; Djimon Marcel Zannou; Gilles Wandeler; Matthias Egger; East Africa; West Africa
BACKGROUND HIV-1 viral load (VL) testing is recommended to monitor antiretroviral therapy (ART) but not universally available. We examined monitoring of first-line and switching to second-line ART in sub-Saharan Africa, 2004-2013. METHODS Adult HIV-1 infected patients starting combination ART in 16 countries were included. Switching was defined as a change from a non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen to a protease inhibitor (PI)-based regimen, with a change of ≥1 NRTI. Virological and immunological failures were defined per World Health Organization criteria. We calculated cumulative probabilities of switching and hazard ratios with 95% confidence intervals (CI) comparing routine VL monitoring, targeted VL monitoring, CD4 cell monitoring and clinical monitoring, adjusted for programme and individual characteristics. FINDINGS Of 297,825 eligible patients, 10,352 patients (3·5%) switched during 782,412 person-years of follow-up. Compared to CD4 monitoring hazard ratios for switching were 3·15 (95% CI 2·92-3·40) for routine VL, 1·21 (1·13-1·30) for targeted VL and 0·49 (0·43-0·56) for clinical monitoring. Overall 58.0% of patients with confirmed virological and 19·3% of patients with confirmed immunological failure switched within 2 years. Among patients who switched the percentage with evidence of treatment failure based on a single CD4 or VL measurement ranged from 32·1% with clinical to 84.3% with targeted VL monitoring. Median CD4 counts at switching were 215 cells/µl under routine VL monitoring but lower with other monitoring (114-133 cells/µl). INTERPRETATION Overall few patients switched to second-line ART and switching occurred late in the absence of routine viral load monitoring. Switching was more common and occurred earlier with targeted or routine viral load testing.BACKGROUND HIV-1 viral load testing is recommended to monitor antiretroviral therapy (ART) but is not universally available. The aim of our study was to assess monitoring of first-line ART and switching to second-line ART in sub-Saharan Africa. METHODS We did a collaborative analysis of cohort studies from 16 countries in east Africa, southern Africa, and west Africa that participate in the international epidemiological database to evaluate AIDS (IeDEA). We included adults infected with HIV-1 who started combination ART between January, 2004, and January, 2013. We defined switching of ART as a change from a non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen to one including a protease inhibitor, with adjustment of one or more nucleoside reverse-transcriptase inhibitors (NRTIs). Virological and immunological failures were defined according to WHO criteria. We calculated cumulative probabilities of switching and hazard ratios with 95% CIs comparing routine viral load monitoring, targeted viral load monitoring, CD4 monitoring, and clinical monitoring, adjusting for programme and individual characteristics. FINDINGS Of 297,825 eligible patients, 10,352 (3%) switched to second-line ART during 782 ,412 person-years of follow-up. Compared with CD4 monitoring, hazard ratios for switching were 3·15 (95% CI 2·92-3·40) for routine viral load monitoring, 1·21 (1·13-1·30) for targeted viral load monitoring, and 0·49 (0·43-0·56) for clinical monitoring. Of 6450 patients with confirmed virological failure, 58·0% (95% CI 56·5-59·6) switched by 2 years, and of 15,892 patients with confirmed immunological failure, 19·3% (18·5-20·0) switched by 2 years. Of 10,352 patients who switched, evidence of treatment failure based on one CD4 count or viral load measurement ranged from 86 (32%) of 268 patients with clinical monitoring to 3754 (84%) of 4452 with targeted viral load monitoring. Median CD4 counts at switching were 215 cells per μL (IQR 117-335) with routine viral load monitoring, but were lower with other types of monitoring (range 114-133 cells per μL). INTERPRETATION Overall, few patients switched to second-line ART and switching happened late in the absence of routine viral load monitoring. Switching was more common and happened earlier after initiation of ART with targeted or routine viral load testing. FUNDING National Institute of Allergy and Infectious Diseases, Swiss National Science Foundation.
The Lancet HIV | 2016
Janne Estill; Nathan Ford; Luisa Salazar-Vizcaya; Andreas D Haas; Nello Blaser; Vincent Habiyambere; Olivia Keiser
BACKGROUND The number of patients in need of second-line antiretroviral drugs is increasing in sub-Saharan Africa. We aimed to project the need of second-line antiretroviral therapy in adults in sub-Saharan Africa up to 2030. METHODS We developed a simulation model for HIV and applied it to each sub-Saharan African country. We used the WHO country intelligence database to estimate the number of adult patients receiving antiretroviral therapy from 2005 to 2014. We fitted the number of adult patients receiving antiretroviral therapy to observed estimates, and predicted first-line and second-line needs between 2015 and 2030. We present results for sub-Saharan Africa, and eight selected countries. We present 18 scenarios, combining the availability of viral load monitoring, speed of antiretroviral scale-up, and rates of retention and switching to second-line. HIV transmission was not included. FINDINGS Depending on the scenario, 8·7-25·6 million people are expected to receive antiretroviral therapy in 2020, of whom 0·5-3·0 million will be receiving second-line antiretroviral therapy. The proportion of patients on treatment receiving second-line therapy was highest (15·6%) in the scenario with perfect retention and immediate switching, no further scale-up, and universal routine viral load monitoring. In 2030, the estimated range of patients receiving antiretroviral therapy will remain constant, but the number of patients receiving second-line antiretroviral therapy will increase to 0·8-4·6 million (6·6-19·6%). The need for second-line antiretroviral therapy was two to three times higher if routine viral load monitoring was implemented throughout the region, compared with a scenario of no further viral load monitoring scale-up. For each monitoring strategy, the future proportion of patients receiving second-line antiretroviral therapy differed only minimally between countries. INTERPRETATION Donors and countries in sub-Saharan Africa should prepare for a substantial increase in the need for second-line drugs during the next few years as access to viral load monitoring improves. An urgent need exists to decrease the costs of second-line drugs. FUNDING World Health Organization, Swiss National Science Foundation, National Institutes of Health.
Journal of Acquired Immune Deficiency Syndromes | 2015
Mireille Porter; Mary-Ann Davies; Muntanga Mapani; Helena Rabie; Sam Phiri; James Nuttall; Lee Fairlie; Karl-Günter Technau; Kathryn Stinson; Robin Wood; Maureen Wellington; Andreas D Haas; Janet Giddy; Frank Tanser; Brian Eley
Background:There are limited published data on the outcomes of infants starting antiretroviral therapy (ART) in routine care in Southern Africa. This study aimed to examine the baseline characteristics and outcomes of infants initiating ART. Methods:We analyzed prospectively collected cohort data from routine ART initiation in infants from 11 cohorts contributing to the International Epidemiologic Database to Evaluate AIDS in Southern Africa. We included ART-naive HIV-infected infants aged <12 months initiating ≥3 antiretroviral drugs between 2004 and 2012. Kaplan–Meier estimates were calculated for mortality, loss to follow-up (LTFU), transfer out, and virological suppression. We used Cox proportional hazard models stratified by cohort to determine baseline characteristics associated with outcomes mortality and virological suppression. Results:The median (interquartile range) age at ART initiation of 4945 infants was 5.9 months (3.7–8.7) with follow-up of 11.2 months (2.8–20.0). At ART initiation, 77% had WHO clinical stage 3 or 4 disease and 87% were severely immunosuppressed. Three-year mortality probability was 16% and LTFU 29%. Severe immunosuppression, WHO stage 3 or 4, anemia, being severely underweight, and initiation of treatment before 2010 were associated with higher mortality. At 12 months after ART initiation, 17% of infants were severely immunosuppressed and the probability of attaining virological suppression was 56%. Conclusions:Most infants initiating ART in Southern Africa had severe disease with high probability of LTFU and mortality on ART. Although the majority of infants remaining in care showed immune recovery and virological suppression, these responses were suboptimal.
Journal of Acquired Immune Deficiency Syndromes | 2015
Lyson Tenthani; Andreas D Haas; Matthias Egger; Joep J. van Oosterhout; Andreas Jahn; Frank Chimbwandira; Kali Tal; Landon Myer; Janne Estill; Olivia Keiser
Abstract:Malawi adopted the Option B+ strategy in 2011. Its success in reducing mother-to-child transmission depends on coverage and timing of HIV testing. We assessed HIV status ascertainment and its predictors during pregnancy. HIV status ascertainment was 82.3% (95% confidence interval: 80.2 to 85.9) in the pre-Option B+ period and 85.7% (95% confidence interval: 83.4 to 88.0) in the Option B+ period. Higher HIV ascertainment was independently associated with higher age, attending antenatal care more than once, and registration in 2010. The observed high variability of HIV ascertainment between sites (50.6%–97.7%) and over time suggests that HIV test kit shortages and insufficient numbers of staff posed major barriers to reducing mother-to-child transmission.
AIDS | 2016
Hannock Tweya; Olivia Keiser; Andreas D Haas; Lyson Tenthani; Sam Phiri; Matthias Egger; Janne Estill
Objective:To estimate the cost-effectiveness of prevention of mother-to-child transmission (MTCT) of HIV with lifelong antiretroviral therapy (ART) for pregnant and breastfeeding women (‘Option B+’) compared with ART during pregnancy or breastfeeding only unless clinically indicated (‘Option B’). Design:Mathematical modelling study of first and second pregnancy, informed by data from the Malawi Option B+ programme. Methods:Individual-based simulation model. We simulated cohorts of 10 000 women and their infants during two subsequent pregnancies, including the breastfeeding period, with either Option B+ or B. We parameterized the model with data from the literature and by analysing programmatic data. We compared total costs of antenatal and postnatal care, and lifetime costs and disability-adjusted life-years of the infected infants between Option B+ and Option B. Results:During the first pregnancy, 15% of the infants born to HIV-infected mothers acquired the infection. With Option B+, 39% of the women were on ART at the beginning of the second pregnancy, compared with 18% with Option B. For second pregnancies, the rates MTCT were 11.3% with Option B+ and 12.3% with Option B. The incremental cost-effectiveness ratio comparing the two options ranged between about US
AIDS | 2014
Luisa Salazar-Vizcaya; Olivia Keiser; Karl Technau; Mary-Ann Davies; Andreas D Haas; Nello Blaser; Vivian Cox; Brian Eley; Helena Rabie; Harry Moultrie; Janet Giddy; Robin Wood; Matthias Egger; Janne Estill
500 and US