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Urine and Saliva: Relevant Specimens for Malaria Diagnosis? Diagnostics (Basel) 2022; 12:diagnostics12122989. [PMID: 36552996 PMCID: PMC9777261 DOI: 10.3390/diagnostics12122989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/20/2022] [Accepted: 11/25/2022] [Indexed: 12/05/2022] Open
Abstract
Blood remains the specimen of preference for malaria diagnosis, whether it is for microscopic, nucleic acid-based or biomarker detection of Plasmodium present in a patient. However, concerning the disadvantages of blood drawing, specimens that can be non-invasively collected under non-hygienic settings would come in handy for malaria diagnosis in endemic areas with limited resources. Although the current approaches using saliva or urine might not be as sensitive and specific as using blood, the potential of these two specimens should not be underestimated and efforts in developing diagnostic methods for Plasmodium detection specifically in these two specimens should continue without giving up. This review not only compiles and summarizes the sensitivity and specificity achieved by various detection approaches when using these samples for malaria diagnosis, it also intends to enhance the possibility of using saliva and urine for diagnostic purposes by describing how Plasmodium nucleic acid and antigens may likely be present in these samples. This review may hopefully encourage and motivate researchers in developing saliva- and urine-based diagnostic methods for Plasmodium detection to facilitate the control and eradication of malaria. In summary, the presence of Plasmodium DNA and antigens in urine and saliva makes these two specimens relevant and useful for malaria diagnosis.
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Leski TA, Taitt CR, Bangura U, Lahai J, Lamin JM, Baio V, Koroma MS, Swaray AG, Jacobsen KH, Jackson O, Jones BW, Phillips CL, Ansumana R, Stenger DA. Comparison of capillary and venous blood for malaria detection using two PCR-based assays in febrile patients in Sierra Leone. Malar J 2021; 20:133. [PMID: 33676502 PMCID: PMC7936501 DOI: 10.1186/s12936-021-03644-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/08/2021] [Accepted: 02/10/2021] [Indexed: 11/17/2022] Open
Abstract
Background Rapid and sensitive diagnostics are critical tools for clinical case management and public health control efforts. Both capillary and venous blood are currently used for malaria detection and while diagnostic technologies may not be equally sensitive with both materials, the published data on this subject are scarce and not conclusive. Methods Paired clinical samples of venous and capillary blood from 141 febrile individuals in Bo, Sierra Leone, were obtained between January and May 2019 and tested for the presence of Plasmodium parasites using two multiplexed PCR assays: the FilmArray-based Global Fever Panel (GFP) and the TaqMan-based Malaria Multiplex Sample Ready (MMSR) assay. Results No significant differences in Plasmodium parasite detection between capillary and venous blood for both assays were observed. The GFP assay was more sensitive than MMSR for all markers that could be compared (Plasmodium spp. and Plasmodium falciparum) in both venous and capillary blood. Conclusions No difference was found in malaria detection between venous and capillary blood using two different PCR-based detection assays. This data gives support for use of capillary blood, a material which can be obtained easier by less invasive methods, for PCR-based malaria diagnostics, independent of the platform.
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Affiliation(s)
- Tomasz A Leski
- Center for Bio/Molecular Science & Engineering, U.S. Naval Research Laboratory, Washington, DC, USA.
| | - Chris Rowe Taitt
- Center for Bio/Molecular Science & Engineering, U.S. Naval Research Laboratory, Washington, DC, USA
| | - Umaru Bangura
- Mercy Hospital Research Laboratory, Bo, Sierra Leone
| | - Joseph Lahai
- Mercy Hospital Research Laboratory, Bo, Sierra Leone
| | | | - Victoria Baio
- Mercy Hospital Research Laboratory, Bo, Sierra Leone
| | | | - Abdulai G Swaray
- College of Science, George Mason University, Fairfax, Virginia, USA
| | - Kathryn H Jacobsen
- Department of Global & Community Health, George Mason University, Fairfax, Virginia, USA
| | | | | | | | - Rashid Ansumana
- Mercy Hospital Research Laboratory, Bo, Sierra Leone.,Njala University, Bo, Sierra Leone
| | - David A Stenger
- Center for Bio/Molecular Science & Engineering, U.S. Naval Research Laboratory, Washington, DC, USA
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Pigeault R, Isaïa J, Yerbanga RS, Dabiré KR, Ouédraogo JB, Cohuet A, Lefèvre T, Christe P. Different distribution of malaria parasite in left and right extremities of vertebrate hosts translates into differences in parasite transmission. Sci Rep 2020; 10:10183. [PMID: 32576924 PMCID: PMC7311528 DOI: 10.1038/s41598-020-67180-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 06/04/2020] [Indexed: 11/16/2022] Open
Abstract
Malaria, a vector-borne disease caused by Plasmodium spp., remains a major global cause of mortality. Optimization of disease control strategies requires a thorough understanding of the processes underlying parasite transmission. While the number of transmissible stages (gametocytes) of Plasmodium in blood is frequently used as an indicator of host-to-mosquito transmission potential, this relationship is not always clear. Significant effort has been made in developing molecular tools that improve gametocyte density estimation and therefore prediction of mosquito infection rates. However a significant level of uncertainty around estimates remains. The weakness in the relationship between gametocyte burden, measured from a blood sample, and the mosquito infection rate could be explained by a non-homogeneous distribution of gametocytes in the bloodstream. The estimated gametocyte density would then only be a single snapshot that does not reflect the host infectivity. This aspect of Plasmodium infection, however, remains largely neglected. In both humans and birds, we found here that the gametocyte densities differed depending on which side of the body the sample was taken, suggesting that gametocytes are not homogeneously distributed within the vertebrate host. We observed a fluctuating asymmetry, in other words, the extremity of the body with the highest density of parasites is not always the same from one individual to another. An estimation of gametocyte density from only one blood sample, as is commonly measured, could, therefore, over- or underestimated the infectivity of gametocyte carriers. This might have important consequences on the epidemiology of the disease since we show that this variation influences host-to-mosquito transmission. Vectors fed on the least infected body part had a lower parasite burden than those fed on the most infected part. The heterogeneous distribution of gametocytes in bloodstream should be considered to improve diagnosis and test new malaria control strategies.
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Affiliation(s)
- Romain Pigeault
- Department of Ecology and Evolution, CH-1015, Lausanne, Switzerland.
| | - Julie Isaïa
- Department of Ecology and Evolution, CH-1015, Lausanne, Switzerland
| | | | - Kounbobr R Dabiré
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | | | - Anna Cohuet
- Unité MIVEGEC, IRD 224-CNRS 5290-Université Montpellier, Montpellier, France
| | - Thierry Lefèvre
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
- Unité MIVEGEC, IRD 224-CNRS 5290-Université Montpellier, Montpellier, France
| | - Philippe Christe
- Department of Ecology and Evolution, CH-1015, Lausanne, Switzerland
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Ararat-Sarria M, Prado CC, Camargo M, Ospina LT, Camargo PA, Curtidor H, Patarroyo MA. Sexual forms obtained in a continuous in vitro cultured Colombian strain of Plasmodium falciparum (FCB2). Malar J 2020; 19:57. [PMID: 32014000 PMCID: PMC6998264 DOI: 10.1186/s12936-020-3142-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 01/25/2020] [Indexed: 12/03/2022] Open
Abstract
Background The epidemiological control of malaria has been hampered by the appearance of parasite resistance to anti-malarial drugs and by the resistance of mosquito vectors to control measures. This has also been associated with weak transmission control, mostly due to poor control of asymptomatic patients associated with host-vector transmission. This highlights the importance of studying the parasite’s sexual forms (gametocytes) which are involved in this phase of the parasite’s life-cycle. Some African and Asian strains of Plasmodium falciparum have been fully characterized regarding sexual forms’ production; however, few Latin-American strains have been so characterized. This study was aimed at characterizing the Colombian FCB2 strain as a gametocyte producer able to infect mosquitoes. Methods Gametocyte production was induced in in vitro cultured P. falciparum FCB2 and 3D7 strains. Pfap2g and Pfs25 gene expression was detected in FCB2 strain gametocyte culture by RT-PCR. Comparative analysis of gametocytes obtained from both strains was made (counts and morphological changes). In vitro zygote formation from FCB2 gametocytes was induced by incubating a gametocyte culture sample at 27 °C for 20 min. A controlled Anopheles albimanus infection was made using an artificial feed system with cultured FCB2 gametocytes (14–15 days old). Mosquito midgut dissection was then carried out for analyzing oocysts. Results The FCB2 strain expressed Pfap2g, Pfs16, Pfg27/25 and Pfs25 sexual differentiation-related genes after in vitro sexual differentiation induction, producing gametocytes that conserved the expected morphological features. The amount of FCB2 gametocytes produced was similar to that from the 3D7 strain. FCB2 gametocytes were differentiated into zygotes and ookinetes after an in vitro low-temperature stimulus and infected An. albimanus mosquitoes, developing to oocyst stage. Conclusions Even with the history of long-term FCB2 strain in vitro culture maintenance, it has retained its sexual differentiation ability. The gametocytes produced here preserved these parasite forms’ usual characteristics and An. albimanus infection capability, thus enabling its use as a tool for studying sexual form biology, An. albimanus infection comparative analysis and anti-malarial drug and vaccine development.
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Affiliation(s)
- Monica Ararat-Sarria
- Receptor-Ligand Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,PhD Programme in Biomedical and Biological Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Cesar Camilo Prado
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Milena Camargo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Laura Tatiana Ospina
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Paola Andrea Camargo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Hernando Curtidor
- Receptor-Ligand Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.,Animal Science Faculty, Universidad de Ciencias Aplicadas y Ambientales (U.D.C.A), Bogotá, Colombia
| | - Manuel Alfonso Patarroyo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia. .,School of Medicine and Health Sciences, Universidad del Rosario, Bogotá, Colombia.
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Lehane A, Were M, Wade M, Hamadu M, Cahill M, Kiconco S, Kajubi R, Aweeka F, Mwebaza N, Li F, Parikh S. Comparison on simultaneous caillary and venous parasite density and genotyping results from children and adults with uncomplicated malaria: a prospective observational study in Uganda. BMC Infect Dis 2019; 19:559. [PMID: 31242863 PMCID: PMC6595677 DOI: 10.1186/s12879-019-4174-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 06/09/2019] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Blood smear microscopy remains the gold-standard method to diagnose and quantify malaria parasite density. In addition, parasite genotyping of select loci is the most utilized method for distinguishing recrudescent and new infections and to determine the number of strains per sample. In research settings, blood may be obtained from capillary or venous compartments, and results from these matrices have been used interchangeably. Our aim was to compare quantitative results for parasite density and strain complexity from both compartments. METHODS In a prospective observational study, children and adults presenting with uncomplicated Plasmodium falciparum malaria, simultaneous capillary and venous blood smears and dried blood spots were collected over 42-days following treatment with artemether-lumefantrine. Blood smears were read by two microscopists, any discrepancies resolved by a third reader. Parasite DNA fingerprinting was conducted using six microsatellites. Bland Altman analysis and paired t-test/McNemar's test were used to assess the difference in density readings and measurements. RESULTS Two hundred twenty-three participants were included in the analysis (177 children (35 HIV-infected/142 HIV-uninfected), 21 HIV-uninfected pregnant women, and 25 HIV-uninfected non-pregnant adults). Parasite density measurements did not statistically differ between capillary and venous blood smears at the time of presentation, nor over the course of 42-day follow-up. Characterization of merozoite surface protein-2 (MSP-2) genetic polymorphism demonstrated a higher level of strain diversity at the time of presentation in venous samples, as compared with capillary specimens (p = 0.02). There was a high degree of variability in genotype-corrected outcomes when pairs of samples from each compartment were compared using MSP-2 alone, although the variability was reduced with the use of multiple markers. CONCLUSIONS Parasite density measurements do not statistically differ between capillary and venous compartments in all studied demographic groups at the time of presentation with malaria, or over the course of follow-up. More strains were detected by MSP-2 genotyping in venous samples than in capillary samples at the time of malaria diagnosis. The use of multiple polymorphic markers reduces the impact of variability in strain detection on genotype-corrected outcomes. This study confirms that both capillary and venous compartments can be used for sampling with confidence in the clinical research setting. TRIAL REGISTRATION The trial was registered at ClinicalTrials.gov under registration no. NCT01717885 .
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Affiliation(s)
- Aine Lehane
- Yale School of Public Health, New Haven, CT USA
| | - Moses Were
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | | | | | - Sylvia Kiconco
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Richard Kajubi
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | - Norah Mwebaza
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Fangyong Li
- Yale School of Public Health, New Haven, CT USA
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Arroyo-Arroyo M, Arango E, Carmona-Fonseca J, Aristizabal B, Yanow S, Maestre A. Efficacy of Different Primaquine Regimens to Control Plasmodium falciparum Gametocytemia in Colombia. Am J Trop Med Hyg 2017; 97:712-718. [PMID: 28749756 DOI: 10.4269/ajtmh.16-0974] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Treatment against Plasmodium falciparum malaria includes blood schizonticides to clear asexual parasites responsible for disease. The addition of gametocytocidal drugs can eliminate infectious sexual stages with potential for transmission and the World Health Organization recommends a single dose (SD) of primaquine (PQ) to this end. The efficacy of PQ at 0.75 mg/kg to suppress gametocytemia when administered in single or fractionated doses was evaluated. A clinical controlled study with an open-label design was executed; three groups of 20 subjects were studied sequentially. All subjects were treated with the standard dose of artemether-lumefantrine plus the total dose of 0.75 mg/kg of PQ administered (without previous G6PD testing) in three different ways: Group "0.75d-3" received 0.75 mg/kg on day 3; Group "0.50d-1 + 0.25d-3" received 0.50 mg/kg on day 1 and 0.25 mg/kg on day 3; Group "0.25d-1,2,3" received 0.25 mg/kg on days 1, 2, and 3. Subjects were evaluated on days 1, 4, and 7 by thick smear microscopy and quantitative polymerase chain reaction to determine the carriage of immature and mature gametocytes. There were no adverse events. The three schemes caused a marked reduction (75-85%) in prevalence of gametocytes on day 4 compared with day 1, but only the group that received 0.75 mg/kg on day 3 maintained the reduced gametocyte burden until day 7. None of the three treatments were able to clear gametocyte carriage on days 4 or 7, but the group that received the SD had the lowest prevalence of gametocytes (15%). Further studies are needed to establish a PQ regimen with complete efficacy against gametocytes.
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Affiliation(s)
- Maria Arroyo-Arroyo
- Grupo Salud y Comunidad, Facultad de Medicina, Universidad de Antioquia, Medellin, Colombia
| | - Eliana Arango
- Grupo Salud y Comunidad, Facultad de Medicina, Universidad de Antioquia, Medellin, Colombia
| | - Jaime Carmona-Fonseca
- Grupo Salud y Comunidad, Facultad de Medicina, Universidad de Antioquia, Medellin, Colombia
| | - Beatriz Aristizabal
- Laboratorio de Biología Molecular, Hospital Pablo Tobon Uribe, Medellin, Colombia
| | - Stephanie Yanow
- School of Public Health, University of Alberta, Edmonton, Alberta, Canada
| | - Amanda Maestre
- Grupo Salud y Comunidad, Facultad de Medicina, Universidad de Antioquia, Medellin, Colombia
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Bouyou-Akotet MK, Tshibola ML, Mawili-Mboumba DP, Nzong J, Bahamontes-Rosa N, Tsoumbou-Bakana G, Kombila M. Frequencies of dhfr/dhps multiple mutations and Plasmodium falciparum submicroscopic gametocyte carriage in Gabonese pregnant women following IPTp-SP implementation. Acta Parasitol 2015. [PMID: 26203988 DOI: 10.1515/ap-2015-0031] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
This study analyzed the relationship between intermittent preventive treatment with sulfadoxine-pyrimethamine (SP) (IPTp-SP), the rate of multiple resistant parasites and of submicroscopic gametocyte carriage among pregnant women at the beginning of IPTp implementation in Gabon (2005) and six years after (2011). The detection of pfdhfr and pfdhps gene mutations was performed by PCR-RFLP in Plasmodium (P.) falciparum positive samples collected from pregnant women in 2005 and 2011. Gametocytes carriage was detected by Pfs25mRNA amplification using QT-NASBA. Data were analyzed according to the time of collection (study period) and IPTp-SP doses. The proportion of isolates with at least a triple Pfdhfr mutation (n = 39/42, 92.9% versus 100%, n = 78/78)) and of those isolates with the S108N/C59R/N51I/S436A/A437G multiple mutation (17.9% versus 75.6%) significantly increased between 2005 and 2011 (p<0.01). Mutations I164L and A581G were not found, while higher proportions of 436 and 437 mutations were detected in 2011.A trend toward a higher frequency of isolates with five mutations was observed in women who received two SP doses (p<0.01). Pfs25mRNA was found in 6.8 % (n = 3/44) and 34.6% (n = 27/78) of the samples collected in 2005 and 2011 respectively (p<0.01). In 2011, 74.0% (n = 20/27) of women with detected submicroscopic gametocytes carried parasites with the S108N/C59R/N51/S436A/A437G multiple mutation. All the ten delivering women who received three IPTp-SP doses had a submicroscopic Plasmodium falciparum infection, but none had detected gametocytes. Following IPTp-SP implementation, an increase in the frequency of multiple mutant parasites and of submicroscopic gametocyte carriage was observed among pregnant women living in Gabon.
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Okebe J, Bousema T, Affara M, DiTanna G, Eziefula AC, Jawara M, Nwakanma D, Amambua-Ngwa A, Van Geertruyden JP, Drakeley C, D'Alessandro U. The gametocytocidal efficacy of primaquine in malaria asymptomatic carriers treated with dihydroartemisinin-piperaquine in The Gambia (PRINOGAM): study protocol for a randomised controlled trial. Trials 2015; 16:70. [PMID: 25887344 PMCID: PMC4349754 DOI: 10.1186/s13063-015-0597-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 02/10/2015] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Finding efficacious tools to decrease and interrupt malaria transmission is essential to sustain the gains in malaria control and contain the emergence of artemisinin resistance. Primaquine is effective against Plasmodium falciparum gametocytes and recommended for treatment campaigns in (pre-)elimination settings. Safety concerns preclude its use in endemic African countries with variable proportions of glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. The efficacy of the current recommended dose needs to be evaluated, particularly in individuals with an asymptomatic malaria infection. METHODS/DESIGN This is a four-arm, open label, randomized controlled trial that aims to determine and compare the effect of three different single doses of primaquine combined with dihydroartemisinin-piperaquine, an artemisinin-based combination therapy, on gametocyte carriage in asymptomatic, malaria infected, G6PD-normal individuals. Approximately 1,200 participants are enrolled and followed for 42 days, with the primary endpoint being the prevalence of Plasmodium falciparum gametocyte carriage at day 7 of follow-up determined by quantitative nucleic acid sequence based amplification assay. Direct membrane feeding experiments to determine infectiousness to mosquitoes are conducted as a biological secondary endpoint. DISCUSSION Sub-Saharan Africa, with a relatively high but poorly characterized G6PD prevalence, could potentially benefit from the use of primaquine to further reduce or interrupt malaria transmission. However, G6PD screening may not be feasible given the cost and difficulties in interpreting test results in terms of risk of haemolysis. Because the haemolytic effect of primaquine is dose-dependent, determining the minimal gametocytocidal and transmission-blocking dose of primaquine is extremely important to help address public health concerns over its safety and validate the efficacy of lower than recommended dosages. By including infectiousness to mosquitoes, the trial provides complementary evidence for the potential of the drug to interrupt transmission to mosquitoes. TRIAL REGISTRATION ClinicalTrials.gov: NCT01838902 (12 April 2013).
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Affiliation(s)
- Joseph Okebe
- Disease Control & Elimination Theme, Medical Research Council Unit, Fajara, The Gambia.
| | - Teun Bousema
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, London, UK.
| | - Muna Affara
- Disease Control & Elimination Theme, Medical Research Council Unit, Fajara, The Gambia.
| | - GianLuca DiTanna
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population health, London School of Hygiene and Tropical Medicine, London, UK.
| | - Alice C Eziefula
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, London, UK.
| | - Musa Jawara
- Disease Control & Elimination Theme, Medical Research Council Unit, Fajara, The Gambia.
| | - Davis Nwakanma
- Disease Control & Elimination Theme, Medical Research Council Unit, Fajara, The Gambia.
| | - Alfred Amambua-Ngwa
- Disease Control & Elimination Theme, Medical Research Council Unit, Fajara, The Gambia.
| | | | - Chris Drakeley
- Immunology and Infection Department, London School of Hygiene and Tropical Medicine, London, UK.
| | - Umberto D'Alessandro
- Disease Control & Elimination Theme, Medical Research Council Unit, Fajara, The Gambia.
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
- Department of Public health, Institute of Tropical Medicine, Antwerp, Belgium.
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