Marcel Tanner

Ifakara Health Institute, Dār es Salām, Dar es Salaam, Tanzania

Are you Marcel Tanner?

Claim your profile

Publications (541)2235.98 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The malaria vaccine RTS,S induces antibodies against the Plasmodium falciparum circumsporozoite protein (CSP) and the concentration of Immunoglobulin G (IgG) against the repeat region of CSP following vaccination is associated with protection from P. falciparum malaria. So far, only the quantity of anti-CSP IgG has been measured and used to predict vaccination success, although quality (measured as avidity) of the antigen-antibody interaction shall be important since only a few sporozoites circulate for a short time after an infectious mosquito bite, likely requiring fast and strong binding. Quantity and avidity of anti-CSP IgG in African infants who received RTS,S/AS01E in a 0-1-2-month or a 0-1-7-month schedule in a phase 2 clinical trial were measured by enzyme-linked immunosorbent assay. Antibody avidity was defined as the proportion of IgG able to bind in the presence of a chaotropic agent (avidity index). The effect of CSP-specific IgG concentration and avidity on protective efficacy was modelled using Cox proportional hazards. After the third dose, quantity and avidity were similar between the two vaccination schedules. IgG avidity after the last vaccine injection was not associated with protection, whereas the change in avidity following second and third RTS,S/AS01E injection was associated with a 54% risk reduction of getting malaria (hazard ratio: 0.46; 95% confidence interval (CI): 0.22-0.99) in those participants with a change in avidity above the median. The change in anti-CSP IgG concentration following second and third injection was associated with a 77% risk reduction of getting malaria (hazard ratio: 0.23, 95% CI: 0.11-0.51). Change in IgG response between vaccine doses merits further evaluation as a surrogate marker for RTS,S efficacy. ClinicalTrials.gov Identifier NCT00436007 .
    Malaria Journal 12/2015; 14(1). DOI:10.1186/s12936-015-0605-7 · 3.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: The Chronic Diseases Clinic Ifakara (CDCI) has been providing HIV care and treatment in Kilombero and Ulanga districts in Tanzania since 2005. Over time, several drug-refilling stations were created through the Tanzanian National AIDS Control Programme (NACP) to provide antiretroviral therapy (ART). Without any specific performance and outcome evaluation, these refilling stations were upgraded to comprehensive HIV care and treatment centres (CTCs). The objectives of this study were to evaluate the supply chain of the CTCs, key aspects of patient management and the coping strategies of theCTC staff andART patients during stock-outs of drugs and test kits. Methods: This explorative and cross-sectional study was undertaken in September 2011 and involved CDCI and all 11 peripheral CTCs in Kilombero and Ulanga districts in Tanzania. Data were collected through structured interviews with staff in charge of 12 sites and patients onART during un-announced visits. Results: All sites reported shortage of rapid tests to diagnose HIV. Seven (59%) CTCs experienced stock-outs of co-trimoxazole drugs. The CDCI and all but one peripheral CTC reported stock-outs of ARV medication. CD4 + T cell count service and second line drugs were available at the CDCI and in two CTCs only. To cope with the stock-out situation CTCs staff had to stop testing for HIV, substitute the treatment regimen depending on drug availability or close the CTC temporarily. Patients coped by skipping ARVs and co-trimoxazole medications. Conclusion: Access to ART in Kilombero and Ulanga districts has some critical imbalances in the supply chain and management for HIV/AIDS care and treatment. Potential strategies to overcome the barriers are discussed in relation to routine health management information system, investments into mobile-health and human resource capacity strengthening.
    Tanzania journal of health research 04/2015; 17(2). DOI:10.4314/thrb.v17i2
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Plasmodium and soil transmitted helminth infections (STH) are a major public health problem, particularly among children. There are conflicting findings on potential association between these two parasites. This study investigated the Plasmodium and helminth co-infections among children aged 2 months to 9 years living in Bagamoyo district, coastal region of Tanzania. A community-based cross-sectional survey was conducted among 1033 children. Stool, urine and blood samples were examined using a broad set of quality controlled diagnostic methods for common STH (Ascaris lumbricoides, hookworm, Strongyloides stercoralis, Enterobius vermicularis, Trichuris trichura), schistosoma species and Wuchereria bancrofti. Blood slides and malaria rapid diagnostic tests (mRDTs) were utilized for Plasmodium diagnosis. Out of 992 children analyzed, the prevalence of Plasmodium infection was 13% (130/992), helminth 28.5% (283/992); 5% (50/992) had co-infection with Plasmodium and helminth. The prevalence rate of Plasmodium, specific STH and co-infections increased significantly with age (p < 0.001), with older children mostly affected except for S. stercoralis monoinfection and co-infections. Spatial variations of co-infection prevalence were observed between and within villages. There was a trend for STH infections to be associated with Plasmodium infection [OR adjusted for age group 1.4, 95% CI (1.0-2.1)], which was more marked for S. stercoralis (OR = 2.2, 95% CI (1.1-4.3). Age and not schooling were risk factors for Plasmodium and STH co-infection. The findings suggest that STH and Plasmodium infections tend to occur in the same children, with increasing prevalence of co-infection with age. This calls for an integrated approach such as using mass chemotherapy with dual effect (e.g., ivermectin) coupled with improved housing, sanitation and hygiene for the control of both parasitic infections.
    PLoS Neglected Tropical Diseases 04/2015; 9(4):e0003660. DOI:10.1371/journal.pntd.0003660 · 4.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To review current and emerging tools for Gambiense HAT control and elimination, and propose strategies that integrate these tools with epidemiological evidence. We reviewed the scientific literature to identify contemporary and emerging tools and strategies for controlling and eliminating Gambiense HAT. Through an iterative process involving key stakeholders, we then developed comprehensive scenarios leading to elimination, considering both established and new tools for diagnosis, case treatment and vector control. Core components of all scenarios include detecting and treating cases with established or emerging techniques. Relatively more intensive scenarios incorporate vector control. New tools considered include tiny targets for tsetse fly control, use of rapid diagnostic tests and oral treatment with fexinidazole or oxaboroles. Scenarios consider the time when critical new tools are expected to become ready for deployment by national control programmes. Based on a review of the latest epidemiological data, we estimate the various interventions to cover 1,380,600 km(2) and 56,986,000 people. A number of new tools will fill critical gaps in the current armamentarium for diagnosing and treating Gambiense HAT. Deploying these tools in endemic areas will facilitate the comprehensive and sustainable control of the disease considerably, and contribute to the ultimate goal of elimination. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Tropical Medicine & International Health 02/2015; DOI:10.1111/tmi.12483 · 2.30 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: From September 23-30, 2005, we conducted a cross-sectional study in six townships of Yopougon, a municipality of Abidjan. These townships were grouped in three levels of urbanization (village, precarious township, and residential township). The main objective of this survey was to determine the impact of urbanization on the malaria infection (parasite) rate and parasite density, and their consequences on the heterogeneity of malaria transmission in urban Abidjan. Specifically we compared these rates in all three urbanization levels, selecting two townships for each level to take environmental specificities observed from previous data into account. The study included 400 households per township. All children younger than 5 years in these households were included. Thick and thin blood smears were taken for each child on slides, and each slide was examined by microscope after staining. The malaria infection rate was 21.8%, indicating mesoendemic malaria. Its distribution varied significantly between the three urbanization levels. Malaria parasite densities also varied significantly between them. These results confirm the involvement of urbanization in the heterogeneity of malaria transmission in the city of Abidjan.
    02/2015; 25(1):69-74. DOI:10.1684/mst.2014.0419
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Around 3.3 million children worldwide are infected with HIV and 90% of them live in sub-Saharan Africa. Our study aimed to estimate adherence levels and find the determinants, facilitators and barriers of ART adherence among children and teenagers in rural Tanzania.Methods We applied a sequential explanatory mixed method design targeting children and teenagers aged 2¿19 years residing in Ifakara. We conducted a quantitative cross sectional study followed by a qualitative study combining focus group discussions (FGDs) and in-depth interviews (IDIs). We used pill count to measure adherence and defined optimal adherence as¿>¿=80% of pills being taken. We analysed determinants of poor adherence using logistic regression. We held eight FGDs with adolescent boys and girls on ART and with caretakers. We further explored issues emerging in the FGDs in four in-depth interviews with patients and health workers. Qualitative data was analysed using thematic content analysis.ResultsOut of 116 participants available for quantitative analysis, 70% had optimal adherence levels and the average adherence level was 84%. Living with a non-parent caretaker predicted poor adherence status. From the qualitative component, unfavorable school environment, timing of the morning ART dose, treatment longevity, being unaware of HIV status, non-parental (biological) care, preference for traditional medicine (herbs) and forgetfulness were seen to be barriers for optimal adherence.Conclusion The study has highlighted specific challenges in ART adherence faced by children and teenagers. Having a biological parent as a caretaker remains a key determinant of adherence among children and teenagers. To achieve optimal adherence, strategies targeting the caretakers, the school environment, and the health system need to be designed.
    BMC Infectious Diseases 01/2015; 15(1):28. DOI:10.1186/s12879-015-0753-y · 2.56 Impact Factor
  • One Health: The Theory and Practice of Integrated Health Approaches, Edited by Jakob Zinsstag, Esther Schelling, David Waltner-Toews, Maxine Whittaker, Marcel Tanner, 01/2015: chapter 27; CAB International.
  • One Health: The Theory and Practice of Integrated Health Approaches, Edited by Jakob Zinsstag, Esther Schelling, David Waltner-Toews, Maxine Whittaker, Marcel Tanner, 01/2015: chapter 9; CAB international.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Two long synthetic peptides representing the dimorphic and constant C-terminal domains of the two allelic families of Plasmodium falciparum merozoite surface proteins 2 are considered promising malaria vaccine candidates. The aim of the current study is to characterize the immune response (epitope mapping) in naturally exposed individuals and relate immune responses to the risk of clinical malaria. To optimize their construction, the fine specificity of human serum antibodies from donors of different age, sex and living in four distinct endemic regions was determined in ELISA by using overlapping 20 mer peptides covering the two domains. Immune purified antibodies were used in Western blot and immunofluorescence assay to recognize native parasite derivate proteins. Immunodominant epitopes were characterized, and their distribution was similar irrespective of geographic origin, age group and gender. Acquisition of a 3D7 family and constant region-specific immune response and antibody avidity maturation occur early in life while a longer period is needed for the corresponding FC27 family response. In addition, the antibody response to individual epitopes within the 3D7 family-specific region contributes to protection from malaria infection with different statistical weight. It is also illustrated that affinity-purified antibodies against the dimorphic or constant regions recognized homologous and heterologous parasites in immunofluorescence and homologous and heterologous MSP2 and other polypeptides in Western blot. Data from this current study may contribute to a development of MSP2 vaccine candidates based on conserved and dimorphic regions thus bypassing the complexity of vaccine development related to the polymorphism of full-length MSP2.
    Malaria Journal 12/2014; 13(1):510. DOI:10.1186/1475-2875-13-510 · 3.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background There is a paucity of data pertaining to the epidemiology and public health impact of Enterobius vermicularis and Strongyloides stercoralis infections. We aimed to determine the extent of enterobiasis, strongyloidiasis, and other helminth infections and their association with asymptomatic Plasmodium parasitaemia, anaemia, nutritional status, and blood cell counts in infants, preschool-aged (PSAC), and school-aged children (SAC) from rural coastal Tanzania.MethodsA total of 1,033 children were included in a cross-sectional study implemented in the Bagamoyo district in 2011/2012. Faecal samples were examined for intestinal helminth infections using a broad set of quality controlled methods. Finger-prick blood samples were subjected to filariasis and Plasmodium parasitaemia testing and full blood cell count examination. Weight, length/height, and/or mid-upper arm circumference were measured and the nutritional status determined in accordance with age.Results E. vermicularis infections were found in 4.2% of infants, 16.7%, of PSAC, and 26.3% of SAC. S. stercoralis infections were detected in 5.8%, 7.5%, and 7.1% of infants, PSAC, and SAC, respectively. Multivariable regression analyses revealed higher odds of enterobiasis in children of all age-groups with a reported anthelminthic treatment history over the past six months (odds ratio (OR): 2.15; 95% confidence interval (CI): 1.22 - 3.79) and in SAC with a higher temperature (OR: 2.21; CI: 1.13 - 4.33). Strongyloidiasis was associated with eosinophilia (OR: 2.04; CI: 1.20-3.48) and with Trichuris trichiura infections (OR: 4.13; CI: 1.04-16.52) in children of all age-groups, and with asymptomatic Plasmodium parasitaemia (OR: 13.03; CI: 1.34 - 127.23) in infants. None of the investigated helminthiases impacted significantly on the nutritional status and anaemia, but moderate asymptomatic Plasmodium parasitaemia was a strong predictor for anaemia in children aged older than two years (OR: 2.69; 95% CI: 1.23 ¿ 5.86).Conclusions E. vermicularis and S. stercoralis infections were moderately prevalent in children from rural coastal Tanzania. Our data can contribute to inform yet missing global burden of disease and prevalence estimates for strongyloidiasis and enterobiasis. The association between S stercoralis and asymptomatic Plasmodium parasitaemia found here warrants further comprehensive investigations.
    BMC Infectious Diseases 12/2014; 14(1):644. DOI:10.1186/s12879-014-0644-7 · 2.56 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The Taabo Health and Demographic Surveillance System (HDSS) is located in south-central Côte d’Ivoire, approximately 150 km north-west of Abidjan. The Taabo HDSS started surveillance activities in early 2009 and the man-made Lake Taabo is a key eco-epidemiological feature. Since inception, there has been a strong interest in research and integrated control of water-associated diseases such as schistosomiasis and malaria. The Taabo HDSS has generated setting-specific evidence on the impact of targeted interventions against malaria, schistosomiasis and other neglected tropical diseases. The Taabo HDSS consists of a small town, 13 villages and over 100 hamlets. At the end of 2013, a total population of 42 480 inhabitants drawn from 6707 households was under surveillance. Verbal autopsies have been conducted to determine causes of death. Repeated cross-sectional epidemiological surveys on approximately 5–7% of the population and specific, layered-on haematological, parasitological and questionnaire surveys have been conducted. The Taabo HDSS provides a database for surveys, facilitates interdisciplinary research, as well as surveillance, and provides a platform for the evaluation of health interventions. Requests to collaborate and to access data are welcome and should be addressed to the secretariat of the Centre Suisse de Recherches Scientifiques en Côte d’Ivoire: [secretariat@csrs.ci].
    International Journal of Epidemiology 11/2014; DOI:10.1093/ije/dyu221 · 9.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Because most deaths in Africa and Asia are not well documented, estimates of mortality are often made using scanty data. The INDEPTH Network works to alleviate this problem by collating detailed individual data from defined Health and Demographic Surveillance sites. By registering all deaths over time and carrying out verbal autopsies to determine cause of death across many such sites, using standardised methods, the Network seeks to generate population-based mortality statistics that are not otherwise available.
    Global Health Action 10/2014; 7:25362. DOI:10.3402/gha.v7.25362 · 1.65 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The presentation of the World Health Organization (WHO)'s Roadmap for neglected tropical diseases (NTDs) in January 2012 raised optimism that many NTDs can indeed be eliminated. To make this happen, the endemic, often low-income countries with still heavy NTD burdens must substantially strengthen their health systems. In particular, they need not only to apply validated, highly sensitive diagnostic tools and sustainable effective control approaches for treatment and transmission control, but also to participate in the development and use of surveillance-response schemes to ensure that progress made also is consolidated and sustained. Surveillance followed-up by public health actions consisting of response packages tailored to interruption of transmission in different settings will help to effectively achieve the disease control/elimination goals by 2020, as anticipated by the WHO Roadmap. Risk-mapping geared at detection of transmission hotspots by means of geospatial and other dynamic approaches facilitates decision-making at the technical as well as the political level. Surveillance should thus be conceived and developed as an intervention approach and at the same time function as an early warning system for the potential re-emergence of endemic infections as well as for new, rapidly spread epidemics and pandemics.
    Acta Tropica 10/2014; 141. DOI:10.1016/j.actatropica.2014.09.017 · 2.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background In the past decade, decreases in clinical episodes and deaths due to malaria have been mainly associated with the expansion of vector-control measures, such as insecticide-treated bednets and indoor residual spraying. Malaria indicator surveys gather information about key malaria indicators through national representative household surveys. We aimed to estimate changes in risk of malaria parasitaemia at high spatial resolution in sub-Saharan Africa, and to quantify the effects of malaria interventions at national and subnational levels. Methods In this spatial and temporal analysis, we analysed data from the six sub-Saharan countries that had publicly available data from two malaria indicator or demographic and health surveys with malaria measurements done in 2006–08 and 2010–12: Angola, Liberia, Mozambique, Senegal, Rwanda, and Tanzania. We used Bayesian geostatistical models to estimate the present malaria risk and to establish the change relative to the period between the last two national surveys. We applied Bayesian variable selection procedures to select the most relevant insecticide-treated-bednet measure for reducing malaria risk, and did spatial kriging over the study region to produce intervention coverage maps. We estimated the contribution of bednets and indoor residual spraying on changes in malaria risk, after adjustment for climatic and socioeconomic factors. Spatially varying coefficients of intervention coverage enabled estimation of their effects at subnational level. Findings In all countries, the probability of decrease in parasitaemia varied substantially between regions. Insecticide-treated bednets were an important intervention for reducing malaria risk, according to different definitions of coverage. An overall effect of insecticide-treated bednets at country level was significant only in Angola (–0·64, 95% credible interval −0·98 to −0·30) and Senegal (–0·34, −0·64 to −0·05); however, in all countries, we detected significant effects of bednets and indoor residual spraying at local level. Interpretation The described methodology is useful for the identification of regions where changes in malaria risk have taken place, and to describe the geographical pattern of malaria. Intervention effects vary in space, which might be driven by local endemicity levels. The produced maps provide a visual aid for national malaria control programmes to identify where targeted strategies and resources are most needed or likely to have the greatest effect on reducing the risk of parasitaemia. Funding Swiss Programme for Research on Global Issues for Development.
    10/2014; 2(10):e601–e615. DOI:10.1016/S2214-109X(14)70300-6
  • 08/2014; DOI:10.4000/vertigo.14976
  • 08/2014; DOI:10.4000/vertigo.14999
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hypothermia contributes to neonatal morbidity and mortality in low-income countries, yet little is known about thermal care practices in rural African settings. We assessed adoption and community acceptability of recommended thermal care practices in rural Tanzania.
    BMC Pregnancy and Childbirth 08/2014; 14(1):267. DOI:10.1186/1471-2393-14-267 · 2.15 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Background:A malaria vaccine could be an important addition to current control strategies. We report the safety and vaccine efficacy (VE) of the RTS,S/AS01 vaccine during 18 mo following vaccination at 11 African sites with varying malaria transmission. Methods and Findings:6,537 infants aged 6–12 wk and 8,923 children aged 5–17 mo were randomized to receive three doses of RTS,S/AS01 or comparator vaccine. VE against clinical malaria in children during the 18 mo after vaccine dose 3 (per protocol) was 46% (95% CI 42% to 50%) (range 40% to 77%; VE, p,0.01 across all sites). VE during the 20 mo after vaccine dose 1 (intention to treat [ITT]) was 45% (95% CI 41% to 49%). VE against severe malaria, malaria hospitalization, and all-cause hospitalization was 34% (95% CI 15% to 48%), 41% (95% CI 30% to 50%), and 19% (95% CI 11% to 27%), respectively (ITT). VE against clinical malaria in infants was 27% (95% CI 20% to 32%, per protocol; 27% [95% CI 21% to 33%], ITT), with no significant protection against severe malaria, malaria hospitalization, or all-cause hospitalization. Postvaccination anti-circumsporozoite antibody geometric mean titer varied from 348 to 787 EU/ml across sites in children and from 117 to 335 EU/ml in infants (per protocol). VE waned over time in both age categories (Schoenfeld residualsp,0.001). The number of clinical and severe malaria cases averted per 1,000 children vaccinated ranged across sites from 37 to 2,365 and from21 to 49, respectively; corresponding ranges among infants were210 to 1,402 and213 to 37, respectively (ITT). Meningitis was reported as a serious adverse event in 16/5,949 and 1/2,974 children and in 9/4,358 and 3/2,179 infants in the RTS,S/AS01 and control groups, respectively. Conclusions:RTS,S/AS01 prevented many cases of clinical and severe malaria over the 18 mo after vaccine dose 3, with the highest impact in areas with the greatest malaria incidence. VE was higher in children than in infants, but even at modest levels of VE, the number of malaria cases averted was substantial. RTS,S/AS01 could be an important addition to current malaria control in Africa. Trial registration:http://www.ClinicalTrials.gov NCT00866619 Please see later in the article for the Editors’ Summary
    PLoS Medicine 07/2014; 11(7). DOI:10.1371/journal.pmed.1001685 · 14.00 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Controlled human malaria infection (CHMI) by mosquito bite has been used to assess new anti-malaria interventions in > 1,500 volunteers since development of methods for infecting mosquitoes by feeding on Plasmodium falciparum (Pf) gametocyte cultures. Such CHMIs have never been used in Africa. Aseptic, purified, cryopreserved Pf sporozoites, PfSPZ Challenge, were used to infect Dutch volunteers by intradermal injection. We conducted a double-blind, placebo-controlled trial to assess safety and infectivity of PfSPZ Challenge in adult male Tanzanians. Volunteers were injected intradermally with 10,000 (N = 12) or 25,000 (N = 12) PfSPZ or normal saline (N = 6). PfSPZ Challenge was well tolerated and safe. Eleven of 12 and 10 of 11 subjects, who received 10,000 and 25,000 PfSPZ, developed parasitemia. In 10,000 versus 25,000 PfSPZ groups geometric mean days from injection to Pf positivity by thick blood film was 15.4 versus 13.5 (P = 0.023). Alpha-thalassemia heterozygosity had no apparent effect on infectivity. PfSPZ Challenge was safe, well tolerated, and infectious.
    The American journal of tropical medicine and hygiene 07/2014; DOI:10.4269/ajtmh.14-0119 · 2.74 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In Sub-Saharan Africa over one million newborns die annually. We developed a sustainable and scalable home-based counselling intervention for delivery by community volunteers in rural southern Tanzania to improve newborn care practices and survival. Here we report the effect on newborn care practices one year after full implementation.
    BMC Pediatrics 07/2014; 14(1):187. DOI:10.1186/1471-2431-14-187 · 1.92 Impact Factor

Publication Stats

16k Citations
2,235.98 Total Impact Points

Institutions

  • 2009–2015
    • Ifakara Health Institute
      Dār es Salām, Dar es Salaam, Tanzania
    • Institut de Formation et de Recherche Démographiques
      Jaúnde, Centre Region, Cameroon
  • 1982–2015
    • Swiss Tropical and Public Health Institute
      • Department of Epidemiology and Public Health
      Bâle, Basel-City, Switzerland
  • 2014
    • Umeå University
      Umeå, Västerbotten, Sweden
  • 2009–2014
    • Universität Basel
      • Swiss Tropical and Public Health Institute (Swiss TPH)
      Bâle, Basel-City, Switzerland
  • 2013
    • Centro de Investigação em Saúde de Manhiça
      Lourenço Marques, Maputo City, Mozambique
  • 2003–2013
    • London School of Hygiene and Tropical Medicine
      • Faculty of Infectious and Tropical Diseases
      London, ENG, United Kingdom
  • 1999–2013
    • University of Queensland 
      • • School of Population Health
      • • Australian Centre for International and Tropical Health (ACITH)
      Brisbane, Queensland, Australia
    • Doctors Without Borders
      Lutetia Parisorum, Île-de-France, France
    • China Academy of Chinese Medical Sciences
      Peping, Beijing, China
  • 2011
    • University of Tuebingen
      • Department of Tropical Medicine
      Tübingen, Baden-Württemberg, Germany
    • Eawag: Das Wasserforschungs-Institut des ETH-Bereichs
      Duebendorf, Zurich, Switzerland
  • 2007–2011
    • Centre Suisse De Recherches Scientifiques En Côte D'Ivoire
      Abijan, Lagunes, Ivory Coast
    • University of Nebraska Medical Center
      • College of Pharmacy
      Omaha, Nebraska, United States
  • 2010
    • Liverpool School of Tropical Medicine
      • Vector Group
      Liverpool, England, United Kingdom
    • Institut National de Recherche en Santé Publique
      Nouakchot, Nouakchott, Mauritania
  • 2006
    • University of Abobo-Adjamé
      Abijan, Lagunes, Ivory Coast
    • University of Barcelona
      Barcino, Catalonia, Spain
    • Muhimbili National Hospital
      Dār es Salām, Dar es Salaam, Tanzania
  • 2005–2006
    • Jiangsu Institute of Parasitic Diseases
      Wu-hsi, Jiangsu Sheng, China
  • 1997–2006
    • University of Zurich
      Zürich, Zurich, Switzerland
    • Johns Hopkins University
      • Department of International Health
      Baltimore, Maryland, United States
  • 2004
    • University of Cambridge
      • Department of Pathology
      Cambridge, ENG, United Kingdom
  • 2001–2004
    • Princeton University
      • Office of Population Research
      Princeton, New Jersey, United States
  • 2002
    • Yunnan Institute Of Parasitic Diseases
      白庙, Shaanxi, China
    • Chinese Center For Disease Control And Prevention
      Peping, Beijing, China
  • 1996–2002
    • Hospital Clínic de Barcelona
      Barcino, Catalonia, Spain
  • 2000
    • National Institute of Parasitic Diseases
      Shanghai, Shanghai Shi, China
    • Queensland Institute of Medical Research
      • Molecular Parasitology Laboratory
      Brisbane, Queensland, Australia
  • 1998
    • The University of Edinburgh
      • Institute of Cell Biology
      Edinburgh, Scotland, United Kingdom
  • 1990
    • Kantonsspital Liestal
      Liestal, Basel-Landschaft, Switzerland
  • 1986–1990
    • University of Geneva
      Genève, Geneva, Switzerland