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Cook J, Sternberg E, Aoura CJ, N'Guessan R, Kleinschmidt I, Koffi AA, Thomas MB, Assi SB. Housing modification for malaria control: impact of a "lethal house lure" intervention on malaria infection prevalence in a cluster randomised control trial in Côte d'Ivoire. BMC Med 2023; 21:168. [PMID: 37143050 PMCID: PMC10161487 DOI: 10.1186/s12916-023-02871-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 04/19/2023] [Indexed: 05/06/2023] Open
Abstract
BACKGROUND In recent years, the downward trajectory of malaria transmission has slowed and, in some places, reversed. New tools are needed to further reduce malaria transmission. One approach that has received recent attention is a novel house-based intervention comprising window screening (S) and general house repairs to make the house more mosquito proof, together with EaveTubes (ET) that provide an innovative way of targeting mosquitoes with insecticides as they search for human hosts at night. The combined approach of Screening + EaveTubes (SET) essentially turns the house into a 'lure and kill' device. METHODS This study evaluated the impact of SET on malaria infection prevalence in Côte d'Ivoire and compares the result in the primary outcome, malaria case incidence. Malaria infection prevalence was measured in a cross-sectional survey in 40 villages, as part of a cluster-randomised trial evaluating the impact of SET on malaria case incidence. RESULTS Infection prevalence, measured by rapid diagnostic test (RDT), was 50.4% and 36.7% in the control arm and intervention arm, respectively, corresponding to an odds ratio of 0.57 (0.45-0.71), p < 0.0001). There was moderate agreement between RDT and microscopy results, with a reduction in odds of infection of 36% recorded when infection was measured by microscopy. Prevalence measured by RDT correlated strongly with incidence at a cluster level. CONCLUSIONS In addition to reducing malaria case incidence, house screening and EaveTubes substantially reduced malaria infection prevalence 18 months after installation. Infection prevalence may be a good metric to use for evaluating malaria interventions in areas of similar transmission levels to this setting. TRIAL REGISTRATION ISRCTN18145556, registered 1 February 2017.
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Affiliation(s)
- Jackie Cook
- International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK.
| | | | | | - Raphael N'Guessan
- Institut Pierre Richet, Bouaké, Côte d'Ivoire
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK
| | - Immo Kleinschmidt
- International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
- Wits Research Institute for Malaria, School of Pathology, University of Witwatersrand, Johannesburg, South Africa
- Southern African Development Community Malaria Elimination Eight Secretariat, Windhoek, Namibia
| | | | - Matthew B Thomas
- Department of Entomology & Nematology and the Invasion Science Research Institute, University of Florida, Gainesville, USA
| | - Serge-Brice Assi
- Institut Pierre Richet, Bouaké, Côte d'Ivoire
- Institut National de Sante Publique, Abidjan, Côte d'Ivoire
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Unterborn R, Henao-Cordero J, Kousari A, Ramanan P, Franco-Paredes C, Madinger N. False-positive rapid diagnostic test for malaria in new world cutaneous leishmaniasis: a tale of two travelers. Ther Adv Infect Dis 2022; 9:20499361221097791. [PMID: 35572813 PMCID: PMC9092576 DOI: 10.1177/20499361221097791] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 04/11/2022] [Indexed: 12/04/2022] Open
Abstract
We report two immigrants from Cuba seen in a US travel clinic with a confirmed
diagnosis of cutaneous leishmaniasis in whom we also suspected malaria
co-infection. Both individuals likely acquired leishmaniasis in the Darien Gap
region of Panama during their migratory path to the United States. As part of
their clinical workup to rule out malaria, a rapid malaria antigen testing for
P. falciparum was obtained and reported positive in both
patients, However, both a qualitative reverse transcription-polymerase chain
reaction (RT-PCR) for Plasmodium falciparum in blood and
repeated thick-and-thin smear direct microscopy were negative in both, deeming
the rapid malaria test as a false-positive. Thus, confirmation of malaria in
travelers requires thick-and-thin film microscopy. Clinicians should be aware of
the growing recognition of the possibility of false-positive malaria rapid
diagnostic tests in those with some forms of leishmaniasis
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Affiliation(s)
- Rebecca Unterborn
- Division of Internal Medicine, Department of Medicine, School of Medicine, University of Colorado Denver, Aurora, CO, USA
| | - Jose Henao-Cordero
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Colorado Denver, Anschutz Medical Campus, 12700 East 19th Avenue, 11C01, Aurora, CO 80045, USA
| | - Arianna Kousari
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Colorado Denver, Aurora, CO, USA
| | - Poornima Ramanan
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Colorado Denver, Aurora, CO, USA
| | - Carlos Franco-Paredes
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Colorado Denver, Aurora, CO, USA
| | - Nancy Madinger
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Colorado Denver, Aurora, CO, USA
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3
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Hosch S, Yoboue CA, Donfack OT, Guirou EA, Dangy JP, Mpina M, Nyakurungu E, Blöchliger K, Guerra CA, Phiri WP, Ayekaba MO, García GA, Tanner M, Daubenberger C, Schindler T. Analysis of nucleic acids extracted from rapid diagnostic tests reveals a significant proportion of false positive test results associated with recent malaria treatment. Malar J 2022; 21:23. [PMID: 35073934 PMCID: PMC8785039 DOI: 10.1186/s12936-022-04043-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 01/07/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Surveillance programmes often use malaria rapid diagnostic tests (RDTs) to determine the proportion of the population carrying parasites in their peripheral blood to assess the malaria transmission intensity. Despite an increasing number of reports on false-negative and false-positive RDT results, there is a lack of systematic quality control activities for RDTs deployed in malaria surveillance programmes. METHODS The diagnostic performance of field-deployed RDTs used for malaria surveys was assessed by retrospective molecular analysis of the blood retained on the tests. RESULTS Of the 2865 RDTs that were collected in 2018 on Bioko Island and analysed in this study, 4.7% had a false-negative result. These false-negative RDTs were associated with low parasite density infections. In 16.6% of analysed samples, masked pfhrp2 and pfhrp3 gene deletions were identified, in which at least one Plasmodium falciparum strain carried a gene deletion. Among all positive RDTs analysed, 28.4% were tested negative by qPCR and therefore considered to be false-positive. Analysing the questionnaire data collected from the participants, this high proportion of false-positive RDTs could be explained by P. falciparum histidine rich protein 2 (PfHRP2) antigen persistence after recent malaria treatment. CONCLUSION Malaria surveillance depending solely on RDTs needs well-integrated quality control procedures to assess the extent and impact of reduced sensitivity and specificity of RDTs on malaria control programmes.
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Affiliation(s)
- Salome Hosch
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Charlene Aya Yoboue
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | | | - Etienne A Guirou
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Maxmillian Mpina
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,Ifakara Health Institute, Bagamoyo, United Republic of Tanzania.,Laboratorio de Investigaciones de Baney, Baney, Equatorial Guinea
| | - Elizabeth Nyakurungu
- Ifakara Health Institute, Bagamoyo, United Republic of Tanzania.,Laboratorio de Investigaciones de Baney, Baney, Equatorial Guinea
| | - Koranan Blöchliger
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Carlos A Guerra
- Medical Care Development International, Malabo, Equatorial Guinea
| | - Wonder P Phiri
- Medical Care Development International, Malabo, Equatorial Guinea
| | | | | | - Marcel Tanner
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Claudia Daubenberger
- Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Tobias Schindler
- Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland. .,Laboratorio de Investigaciones de Baney, Baney, Equatorial Guinea.
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Specificity of SARS-CoV-2 antibody-detection assays against S and N protein among pre-COVID-19 sera from patients with protozoan and helminth parasitic infections. J Clin Microbiol 2021; 60:e0171721. [PMID: 34669455 PMCID: PMC8769729 DOI: 10.1128/jcm.01717-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We aimed to assess the specificity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody detection assays among people with tissue-borne parasitic infections. We tested three SARS-CoV-2 antibody-detection assays (cPass SARS-CoV-2 neutralization antibody detection kit [cPass], Abbott SARS-CoV-2 IgG assay [Abbott Architect], and Standard Q COVID-19 IgM/IgG combo rapid diagnostic test [SD RDT IgM/SD RDT IgG]) among 559 pre-COVID-19 seropositive sera for several parasitic infections. The specificity of assays was 95 to 98% overall. However, lower specificity was observed among sera from patients with protozoan infections of the reticuloendothelial system, such as human African trypanosomiasis (Abbott Architect; 88% [95% CI, 75 to 95]) and visceral leishmaniasis (SD RDT IgG; 80% [95% CI, 30 to 99]), and from patients with recent malaria in areas of Senegal where malaria is holoendemic (ranging from 91% for Abbott Architect and SD RDT IgM to 98 to 99% for cPass and SD RDT IgG). For specimens from patients with evidence of past or present helminth infection overall, test specificity estimates were all ≥96%. Sera collected from patients clinically suspected of parasitic infections that tested negative for these infections yielded a specificity of 98 to 100%. The majority (>85%) of false-positive results were positive by only one assay. The specificity of SARS-CoV-2 serological assays among sera from patients with tissue-borne parasitic infections was below the threshold required for decisions about individual patient care. Specificity is markedly increased by the use of confirmatory testing with a second assay. Finally, the SD RDT IgG proved similarly specific to laboratory-based assays and provides an option in low-resource settings when detection of anti-SARS-CoV-2 IgG is indicated.
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Vanroye F, den Bossche DV, Brosius I, Tack B, Esbroeck MV, Jacobs J. COVID-19 Antibody Detecting Rapid Diagnostic Tests Show High Cross-Reactivity When Challenged with Pre-Pandemic Malaria, Schistosomiasis and Dengue Samples. Diagnostics (Basel) 2021; 11:diagnostics11071163. [PMID: 34202195 PMCID: PMC8305106 DOI: 10.3390/diagnostics11071163] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/23/2021] [Accepted: 06/23/2021] [Indexed: 12/13/2022] Open
Abstract
COVID-19 Antibody Detecting Rapid Diagnostic Tests (COVID-19 Ab RDTs) are the preferred tool for SARS-CoV-2 seroprevalence studies, particularly in low- and middle-income countries. The present study challenged COVID-19 Ab RDTs with pre-pandemic samples of patients exposed to tropical pathogens. A retrospective study was performed on archived serum (n = 94) and EDTA whole blood (n = 126) samples obtained during 2010–2018 from 196 travelers with malaria (n = 170), schistosomiasis (n = 25) and dengue (n = 25). COVID-19 Ab RDTs were selected based on regulatory approval status, independent evaluation results and detecting antigens. Among 13 COVID-19 Ab RDT products, overall cross-reactivity was 18.5%; cross-reactivity for malaria, schistosomiasis and dengue was 20.3%, 18.1% and 7.5%, respectively. Cross-reactivity for current and recent malaria, malaria antibodies, Plasmodium species and parasite densities was similar. Cross-reactivity among the different RDT products ranged from 2.7% to 48.9% (median value 14.5%). IgM represented 67.9% of cross-reactive test lines. Cross-reactivity was not associated with detecting antigens, patient categories or disease (sub)groups, except for schistosomiasis (two products with ≥60% cross-reactivity). The high cross-reactivity for malaria, schistosomiasis and—to a lesser extent—dengue calls for risk mitigation when using COVID-19 Ab RDTs in co-endemic regions.
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Affiliation(s)
- Fien Vanroye
- Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium; (D.V.d.B.); (I.B.); (B.T.); (M.V.E.); (J.J.)
- Correspondence:
| | - Dorien Van den Bossche
- Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium; (D.V.d.B.); (I.B.); (B.T.); (M.V.E.); (J.J.)
| | - Isabel Brosius
- Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium; (D.V.d.B.); (I.B.); (B.T.); (M.V.E.); (J.J.)
| | - Bieke Tack
- Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium; (D.V.d.B.); (I.B.); (B.T.); (M.V.E.); (J.J.)
- Department of Microbiology, Immunology and Transplantation, KU Leuven, 3000 Leuven, Belgium
| | - Marjan Van Esbroeck
- Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium; (D.V.d.B.); (I.B.); (B.T.); (M.V.E.); (J.J.)
| | - Jan Jacobs
- Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium; (D.V.d.B.); (I.B.); (B.T.); (M.V.E.); (J.J.)
- Department of Microbiology, Immunology and Transplantation, KU Leuven, 3000 Leuven, Belgium
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Jacobs J, Kühne V, Lunguya O, Affolabi D, Hardy L, Vandenberg O. Implementing COVID-19 (SARS-CoV-2) Rapid Diagnostic Tests in Sub-Saharan Africa: A Review. Front Med (Lausanne) 2020; 7:557797. [PMID: 33195307 PMCID: PMC7662157 DOI: 10.3389/fmed.2020.557797] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 09/15/2020] [Indexed: 01/23/2023] Open
Abstract
Introduction: For the COVID-19 (SARS-CoV-2) response, COVID-19 antigen (Ag), and antibody (Ab) rapid diagnostic tests (RDTs) are expected to complement central molecular testing particularly in low-resource settings. The present review assesses requirements for implementation of COVID-19 RDTs in sub-Saharan Africa. Methods: Review of PubMed-published articles assessing COVID-19 RDTs complemented with Instructions for Use (IFU) of products. Results: In total 47 articles on two COVID-19 Ag RDTs and 54 COVID-19 Ab RDTs and IFUs of 20 COVID-19 Ab RDTs were retrieved. Only five COVID-19 Ab RDTs (9.3%) were assessed with capillary blood sampling at the point-of-care; none of the studies were conducted in sub-Saharan Africa. Sampling: Challenges for COVID-19 Ag RDTs include nasopharyngeal sampling (technique, biosafety) and sample stability; for COVID-19 Ab RDTs equivalence of whole blood vs. plasma/serum needs further validation (assessed for only eight (14.8%) products). Sensitivity-Specificity: sensitivity of COVID-19 Ag and Ab RDTs depend on viral load (antigen) and timeframe (antibody), respectively; COVID-19 Ab tests have lower sensitivity compared to laboratory test platforms and the kinetics of IgM and IgG are very similar. Reported specificity was high but has not yet been assessed against tropical pathogens. Kit configuration: For COVID-19 Ag RDTs, flocked swabs should be added to the kit; for COVID-19 Ab RDTs, finger prick sampling materials, transfer devices, and controls should be added (currently only supplied in 15, 5, and 1/20 products). Usability and Robustness: some COVID-19 Ab RDTs showed high proportions of faint lines (>40%) or invalid results (>20%). Shortcomings were reported for buffer vials (spills, air bubbles) and their instructions for use. Stability: storage temperature was ≤ 30°C for all but one RDT, in-use and result stability were maximal at 1 h and 30 min, respectively. Integration in the healthcare setting requires a target product profile, landscape overview of technologies, certified manufacturing capacity, a sustainable market, and a stringent but timely regulation. In-country deployment depends on integration in the national laboratory network. Discussion/Conclusion: Despite these limitations, successful implementation models in triage, contact tracing, and surveillance have been proposed, in particular for COVID-19 Ab RDTs. Valuable experience is available from implementation of other disease-specific RDTs in sub-Saharan Africa.
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Affiliation(s)
- Jan Jacobs
- Department of Clinical Sciences, Institute of Tropical Medicine Antwerp, Antwerp, Belgium
- Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Vera Kühne
- Department of Clinical Sciences, Institute of Tropical Medicine Antwerp, Antwerp, Belgium
| | - Octavie Lunguya
- Department of Clinical Microbiology, National Institute of Biomedical Research, Kinshasa, Democratic Republic of Congo
- Microbiology Unit, Department of Clinical Biology, University Hospital of Kinshasa, Kinshasa, Democratic Republic of Congo
| | - Dissou Affolabi
- Clinical Microbiology, Centre National Hospitalier et Universitaire Hubert Koutoukou MAGA, Cotonou, Benin
| | - Liselotte Hardy
- Department of Clinical Sciences, Institute of Tropical Medicine Antwerp, Antwerp, Belgium
| | - Olivier Vandenberg
- Center for Environmental Health and Occupational Health, School of Public Health, Université Libre de Bruxelles (ULB), Brussels, Belgium
- Innovation and Business Development Unit, Laboratoire Hospitalier Universitaire de Bruxelles - Universitair Laboratorium Brussel (LHUB-ULB), ULB, Brussels, Belgium
- Division of Infection and Immunity, Faculty of Medical Sciences, University College London, London, United Kingdom
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Cunningham LJ, Lingley JK, Tirados I, Esterhuizen J, Opiyo M, Mangwiro CTN, Lehane MJ, Torr SJ. Evidence of the absence of human African trypanosomiasis in two northern districts of Uganda: Analyses of cattle, pigs and tsetse flies for the presence of Trypanosoma brucei gambiense. PLoS Negl Trop Dis 2020; 14:e0007737. [PMID: 32255793 PMCID: PMC7164673 DOI: 10.1371/journal.pntd.0007737] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 04/17/2020] [Accepted: 02/20/2020] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Large-scale control of sleeping sickness has led to a decline in the number of cases of Gambian human African trypanosomiasis (g-HAT) to <2000/year. However, achieving complete and lasting interruption of transmission may be difficult because animals may act as reservoir hosts for T. b. gambiense. Our study aims to update our understanding of T. b. gambiense in local vectors and domestic animals of N.W. Uganda. METHODS We collected blood from 2896 cattle and 400 pigs and In addition, 6664 tsetse underwent microscopical examination for the presence of trypanosomes. Trypanosoma species were identified in tsetse from a subsample of 2184 using PCR. Primers specific for T. brucei s.l. and for T. brucei sub-species were used to screen cattle, pig and tsetse samples. RESULTS In total, 39/2,088 (1.9%; 95% CI = 1.9-2.5) cattle, 25/400 (6.3%; 95% CI = 4.1-9.1) pigs and 40/2,184 (1.8%; 95% CI = 1.3-2.5) tsetse, were positive for T. brucei s.l.. Of these samples 24 cattle (61.5%), 15 pig (60%) and 25 tsetse (62.5%) samples had sufficient DNA to be screened using the T. brucei sub-species PCR. Further analysis found no cattle or pigs positive for T. b. gambiense, however, 17/40 of the tsetse samples produced a band suggestive of T. b. gambiense. When three of these 17 PCR products were sequenced the sequences were markedly different to T. b. gambiense, indicating that these flies were not infected with T. b. gambiense. CONCLUSION The lack of T. b. gambiense positives in cattle, pigs and tsetse accords with the low prevalence of g-HAT in the human population. We found no evidence that livestock are acting as reservoir hosts. However, this study highlights the limitations of current methods of detecting and identifying T. b. gambiense which relies on a single copy-gene to discriminate between the different sub-species of T. brucei s.l.
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Affiliation(s)
- Lucas J. Cunningham
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Jessica K. Lingley
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Iñaki Tirados
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Johan Esterhuizen
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Mercy Opiyo
- Institute for Global Health, University of Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Clement T. N. Mangwiro
- Department of Animal Science, Bindura University of Science Education, Bindura, Zimbabwe
| | - Mike J. Lehane
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Stephen J. Torr
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Sanches-Vaz M, Temporão A, Luis R, Nunes-Cabaço H, Mendes AM, Goellner S, Carvalho T, Figueiredo LM, Prudêncio M. Trypanosoma brucei infection protects mice against malaria. PLoS Pathog 2019; 15:e1008145. [PMID: 31703103 PMCID: PMC6867654 DOI: 10.1371/journal.ppat.1008145] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 11/20/2019] [Accepted: 10/11/2019] [Indexed: 12/22/2022] Open
Abstract
Sleeping sickness and malaria are parasitic diseases with overlapping geographical distributions in sub-Saharan Africa. We hypothesized that the immune response elicited by an infection with Trypanosoma brucei, the etiological agent of sleeping sickness, would inhibit a subsequent infection by Plasmodium, the malaria parasite, decreasing the severity of its associated pathology. To investigate this, we established a new co-infection model in which mice were initially infected with T. brucei, followed by administration of P. berghei sporozoites. We observed that a primary infection by T. brucei significantly attenuates a subsequent infection by the malaria parasite, protecting mice from experimental cerebral malaria and prolonging host survival. We further observed that an ongoing T. brucei infection leads to an accumulation of lymphocyte-derived IFN-γ in the liver, limiting the establishment of a subsequent hepatic infection by P. berghei sporozoites. Thus, we identified a novel host-mediated interaction between two parasitic infections, which may be epidemiologically relevant in regions of Trypanosoma/Plasmodium co-endemicity. Despite the geographical overlap between the parasites that cause sleeping sickness and malaria, the reciprocal impact of a co-infection by T. brucei and Plasmodium had hitherto not been assessed. We hypothesized that the strong immune response elicited by a T. brucei infection could potentially limit the ability of Plasmodium parasites to infect the same host. In this study, we showed that a primary infection by T. brucei significantly attenuates a subsequent infection by the malaria parasite. Importantly, a significant proportion of the co-infected mice do not develop Plasmodium parasitemia, and those few that do, do not display symptoms of severe malaria and survive longer than their singly infected counterparts. We further showed that the prevention or delay in appearance of malaria parasites in the blood results from a dramatic impairment of the preceding liver infection by Plasmodium, which is mediated by the strong immune response mounted against the primary T. brucei infection. Our study provides new insights for a novel inter-pathogen interaction that may bear great epidemiological significance in regions of Trypanosoma/Plasmodium co-endemicity.
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Affiliation(s)
- Margarida Sanches-Vaz
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Adriana Temporão
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Rafael Luis
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Helena Nunes-Cabaço
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - António M. Mendes
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Sarah Goellner
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Tânia Carvalho
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Luisa M. Figueiredo
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- * E-mail: (LMF); (MP)
| | - Miguel Prudêncio
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- * E-mail: (LMF); (MP)
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9
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Quakyi IA, Adjei GO, Sullivan DJ, Laar A, Stephens JK, Owusu R, Winch P, Sakyi KS, Coleman N, Krampa FD, Essuman E, Aubyn VNA, Boateng IA, Borteih BB, Vanotoo L, Tuakli J, Addison E, Bart-Plange C, Sorvor F, Adjei AA. Diagnostic capacity, and predictive values of rapid diagnostic tests for accurate diagnosis of Plasmodium falciparum in febrile children in Asante-Akim, Ghana. Malar J 2018; 17:468. [PMID: 30547795 PMCID: PMC6295071 DOI: 10.1186/s12936-018-2613-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 12/05/2018] [Indexed: 12/04/2022] Open
Abstract
Background This study seeks to compare the performance of HRP2 (First Response) and pLDH/HRP2 (Combo) RDTs for falciparum malaria against microscopy and PCR in acutely ill febrile children at presentation and follow-up. Methods This is an interventional study that recruited children < 5 years who reported to health facilities with a history of fever within the past 72 h or a documented axillary temperature of 37.5 °C. Using a longitudinal approach, recruitment and follow-up of participants was done between January and May 2012. Based on results of HRP2-RDT screening, the children were grouped into one of the following three categories: (1) tested positive for malaria using RDT and received anti-malarial treatment (group 1, n = 85); (2) tested negative for malaria using RDT and were given anti-malarial treatment by the admitting physician (group 2, n = 74); or, (3) tested negative for malaria using RDT and did not receive any anti-malarial treatment (group 3, n = 101). Independent microscopy, PCR and Combo-RDT tests were done for each sample on day 0 and all follow-up days. Results Mean age of the study participants was 22 months and females accounted for nearly 50%. At the time of diagnosis, the mean body temperature was 37.9 °C (range 35–40.1 °C). Microscopic parasite density ranged between 300 and 99,500 parasites/µL. With microscopy as gold standard, the sensitivity of HRP2 and Combo-RDTs were 95.1 and 96.3%, respectively. The sensitivities, specificities and predictive values for RDTs were relatively higher in microscopy-defined malaria cases than in PCR positive-defined cases. On day 0, participants who initially tested negative for HRP2 were positive by microscopy (n = 2), Combo (n = 1) and PCR (n = 17). On days 1 and 2, five of the children in this group (initially HRP2-negative) tested positive by PCR alone. On day 28, four patients who were originally HRP2-negative tested positive for microscopy (n = 2), Combo (n = 2) and PCR (n = 4). Conclusion The HRP2/pLDH RDTs showed comparable diagnostic accuracy in children presenting with an acute febrile illness to health facilities in a hard-to-reach rural area in Ghana. Nevertheless, discordant results recorded on day 0 and follow-up visits using the recommended RDTs means improved malaria diagnostic capability in malaria-endemic regions is necessary.
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Affiliation(s)
- Isabella A Quakyi
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - George O Adjei
- Centre for Tropical Clinical Pharmacology and Therapeutics, School of Medicine and Dentistry, University of Ghana, Accra, Ghana
| | - David J Sullivan
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe St, Baltimore, MD, 21205, USA
| | - Amos Laar
- Department of Population, Family, and Reproductive Health, School of Public Health, University of Ghana, Legon, Accra, Ghana
| | - Judith K Stephens
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Richmond Owusu
- Department of Health Policy, Planning and Management, School of Public Health, University of Ghana, Legon, Accra, Ghana
| | - Peter Winch
- Department of International Health, Social and Behavioural Interventions Program, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe St, Baltimore, MD, 21205, USA
| | - Kwame S Sakyi
- Department of Public and Environmental Wellness, Oakland University, 3101 Human Health Building, 433 Meadow Brook Rd, Rochester, MI, 48309-4452, USA
| | - Nathaniel Coleman
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Francis D Krampa
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Edward Essuman
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Vivian N A Aubyn
- National Malaria Control Programme, Ministry of Health, Accra, Ghana
| | - Isaac A Boateng
- Asante-Akim Central Municipal Health Directorate, Ghana Health Services, Konongo, Ghana
| | - Bernard B Borteih
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Linda Vanotoo
- Regional Health Directorate, Ghana Health Services, Accra, Ghana
| | | | | | | | - Felix Sorvor
- Department of Biological, Environmental and Occupational Health Sciences, School of Public Health, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Andrew A Adjei
- Worldwide Universities Network, University of Ghana, P.O. Box LG 13, Legon, Accra, Ghana.
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Nkenfou CN, Hell VN, Georges NT, Ngoufack MN, Nkenfou CN, Kamgaing N, Ndjolo A. USAGE OF A RAPID DIAGNOSTIC TEST FOR MALARIA IN CHILDREN. Afr J Infect Dis 2018; 13:24-31. [PMID: 30596193 PMCID: PMC6305079 DOI: 10.21010/ajid.v13i1.3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 06/14/2017] [Accepted: 07/12/2017] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Malaria is still the primary cause of pediatric deaths. The efficient management of pediatric malaria requires its rapid and accurate diagnosis. To fulfill this requirement, rapid diagnostic tests have been developed, but their evaluation before commercialization is never exhaustive. The aim of this study was to evaluate the performance of a rapid diagnostic test (SD Bioline Malaria Antigen P.f/Pan) to diagnose malaria in children. MATERIALS AND METHODS Testing was conducted on children aged between 6 months and 15 years who were examined at the "Centre Mère Enfant (CME) of the "Chantal Biya" Foundation (FCB). as a result of fever. Enrollment took place from April to October 2014. All children presenting with fever were sampled (3ml of blood). These blood samples were tested for malaria using microscopy on a thick blood smear and by a rapid diagnostic test (RDT) SD Bioline Malariae Antigen P.f/Pan. RESULTS A total of 249 children were enrolled in this study. Malaria presence as determined by microscopy and by RDT was 30.9% and 58.2% respectively. The sensitivity, specificity, positive and negative predictive values compared to microscopy were: 75; 48.8; 39, and 81.6%. With these performances, the malaria SD Bioline rapid test presents lower values compared to WHO recommendations for rapid tests (sensitivity > 95%) in children. CONCLUSION SD Bioline Malaria Antigen P.f/Pan test should only be used in peripheral health structures that lack resources, and should be aided by clinical diagnosis.
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Affiliation(s)
- Céline Nguefeu Nkenfou
- Laboratory of Systems Biology, “Chantal Biya” International Reference Centre for Research on HIV/AIDS Prevention and Management (CBIRC), Yaounde, Cameroon
- Department of Biological Sciences, Higher Teacher Training College, University of Yaounde I, Yaounde, Cameroon
| | - Vestale Ngo Hell
- Catholic University, School of Health Sciences, Yaounde, Cameroon
| | | | - Marie Nicole Ngoufack
- Laboratory of Systems Biology, “Chantal Biya” International Reference Centre for Research on HIV/AIDS Prevention and Management (CBIRC), Yaounde, Cameroon
- Faculty of Sciences, University of Yaounde I, Yaounde, Cameroon
| | | | - Nelly Kamgaing
- Laboratory of Systems Biology, “Chantal Biya” International Reference Centre for Research on HIV/AIDS Prevention and Management (CBIRC), Yaounde, Cameroon
- Faculty of Medicine and Biomedical Sciences, University of Yaounde, Yaounde, Cameroon
| | - Alexis Ndjolo
- Laboratory of Systems Biology, “Chantal Biya” International Reference Centre for Research on HIV/AIDS Prevention and Management (CBIRC), Yaounde, Cameroon
- Faculty of Medicine and Biomedical Sciences, University of Yaounde, Yaounde, Cameroon
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11
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Kiemde F, Tahita MC, Bonko MDA, Mens PF, Tinto H, van Hensbroek MB, Schallig HDFH. Implementation of a malaria rapid diagnostic test in a rural setting of Nanoro, Burkina Faso: from expectation to reality. Malar J 2018; 17:316. [PMID: 30165849 PMCID: PMC6117982 DOI: 10.1186/s12936-018-2468-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 08/27/2018] [Indexed: 01/16/2023] Open
Abstract
Background Malaria rapid diagnostic tests (RDTs) are nowadays widely used in malaria endemic countries as an alternative to microscopy for the diagnosis of malaria. However, quality control of test performance and execution in the field are important in order to ensure proper use and adequate diagnosis of malaria. The current study compared the performance of a histidine-rich protein 2-based RDT used at peripheral health facilities level in real life conditions with that performed at central reference laboratory level with strict adherence to manufacturer instructions. Methods Febrile children attending rural health clinics were tested for malaria with a RDT provided by the Ministry of Health of Burkina Faso as recommended by the National Malaria Control Programme. In addition, a blood sample was collected in an EDTA tube from all study cases for retesting with the same brand of RDT following the manufacturer’s instructions with expert malaria microscopy as gold standard at the central reference laboratory. Fisher exact test was used to compare the proportions by estimating the p-value (p ≤ 0.05) as statistically significant. Results In total, 407 febrile children were included in the study and malaria was diagnosed in 59.9% (244/407) of the cases with expert malaria microscopy. The sensitivity of malaria RDT testing performed at health facilities was 97.5% and comparable to that achieved at the laboratory (98.8%). The number of malaria false negatives was not statistically significant between the two groups (p = 0.5209). However, the malaria RDT testing performed at health facilities had a specificity issue (52.8%) and was much lower compared to RDT testing performed at laboratory (74.2%). The number of malaria false positives was statistically significantly different between the two groups (p = 0.0005). Conclusion Malaria RDT testing performed at the participating rural health facilities resulted in more malaria false positives compared to those performed at central laboratory. Several factors, including storage and transportation conditions but also training of health workers, are most likely to influence test performance. Therefore, it is very important to have appropriate quality control and training programmes in place to ensure correct performance of RDT testing.
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Affiliation(s)
- Francois Kiemde
- Institut de Recherche en Science de la Sante-Unité de Recherche Clinique de Nanoro, Nanoro, Burkina Faso. .,Parasitology Unit, Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands. .,Global Child Health Group, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
| | - Marc Christian Tahita
- Institut de Recherche en Science de la Sante-Unité de Recherche Clinique de Nanoro, Nanoro, Burkina Faso
| | - Massa Dit Achille Bonko
- Institut de Recherche en Science de la Sante-Unité de Recherche Clinique de Nanoro, Nanoro, Burkina Faso.,Parasitology Unit, Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Petra F Mens
- Parasitology Unit, Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Halidou Tinto
- Institut de Recherche en Science de la Sante-Unité de Recherche Clinique de Nanoro, Nanoro, Burkina Faso
| | | | - Henk D F H Schallig
- Parasitology Unit, Department of Medical Microbiology, Academic Medical Centre, Amsterdam, The Netherlands
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An assessment of false positive rates for malaria rapid diagnostic tests caused by non-Plasmodium infectious agents and immunological factors. PLoS One 2018; 13:e0197395. [PMID: 29758050 PMCID: PMC5951549 DOI: 10.1371/journal.pone.0197395] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 05/01/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Malaria rapid diagnostic tests (RDTs) can produce false positive (FP) results in patients with human African trypanosomiasis and rheumatoid factor (RF), but specificity against other infectious agents and immunological factors is largely unknown. Low diagnostic specificity caused by cross-reactivity may lead to over-estimates of the number of malaria cases and over-use of antimalarial drugs, at the cost of not diagnosing and treating the true underlying condition. METHODS Data from the WHO Malaria RDT Product Testing Programme was analysed to assess FP rates of 221 RDTs against four infectious agents (Chagas, dengue, Leishmaniasis and Schistosomiasis) and four immunological factors (anti-nuclear antibody, human anti-mouse antibody (HAMA), RF and rapid plasma regain). Only RDTs with a FP rate against clean negative samples less than 10% were included. Paired t-tests were used to compare product-specific FP rates on clean negative samples and samples containing non-Plasmodium infectious agents and immunological factors. RESULTS Forty (18%) RDTs showed no FP results against any tested infectious agent or immunological factor. In the remaining RDTs significant and clinically relevant increases in FP rates were observed for samples containing HAMA and RF (P<0.001). There were significant correlations between product-matched FP rates for RF and HAMA on all RDT test bands (P<0.001), and FP rates for each infectious agent and immunological factor were also correlated between test bands of combination RDTs (P≤0.002). CONCLUSIONS False positive results against non-Plasmodium infectious agents and immunological factors does not appear to be a universal property of malaria RDTs. However, since many malaria RDTs have elevated FP rates against HAMA and RF positive samples practitioners may need to consider the possibility of false positive results for malaria in patients with conditions that stimulate HAMA or RF.
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13
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Matovu E, Kitibwa A, Picado A, Biéler S, Bessell PR, Ndung'u JM. Serological tests for gambiense human African trypanosomiasis detect antibodies in cattle. Parasit Vectors 2017; 10:546. [PMID: 29100526 PMCID: PMC5670715 DOI: 10.1186/s13071-017-2487-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 10/19/2017] [Indexed: 11/23/2022] Open
Abstract
Background Serological tests for gambiense human African trypanosomiasis (gHAT) detect antibodies to antigens on the cell surface of bloodstream trypanosomes. As trypanosomes that cause animal African trypanosomiasis (AAT) also express related antigens, we have evaluated two rapid diagnostic tests (RDTs) on cattle in trypanosomiasis endemic and non-endemic regions, to determine whether gHAT serological tests could also be used to screen for AAT. Methods Two RDTs, 1G RDT, made with native antigens, and p2G RDT, made with recombinant antigens, were tested on 121 cattle in a trypanosomiasis-free region, and on 312 cattle from a rhodesiense HAT and AAT endemic region. A subset of samples from the endemic region were also tested with two immune trypanolysis (TL) tests. The sensitivity of the tests was estimated by evaluating the result of the RDT on samples that were positive by both microscopy and internal transcribed spacer (ITS) PCR, whilst specificity was the result of the RDT on samples that were negative by ITS PCR and microscopy, and others from the non-endemic region. Results The specificity of the p2G RDT on cattle from the non-endemic region was 97.5% (95% CI: 93.0–99.2%), compared to only 57.9% (95% CI: 48.9–66.3%) for 1G RDT. The specificities of 1G RDT, p2G RDT and TL on endemic control cattle were 14.6% (95% CI: 9.7–21.5%), 22.6% (95% CI: 16.4–30.3%) and 68.3% (95% CI: 59.6–75.9%), respectively. The sensitivities of the tests on trypanosome positive samples were 85.1% (95% CI: 79.1–89.7%), 89.1% (95% CI: 83.7–93.0%) and 59.3% (95% CI: 51.8–66.4%), respectively. Among the same samples, 51.7% were positive by both TL and the 1G RDT. Conclusions These serological tests detect cross-reacting antibodies in cattle. The p2G RDT based on recombinant antigens had a high specificity in a non-endemic region, while the 1G RDT had a lower specificity, suggesting cross-reactivity with other pathogens. Electronic supplementary material The online version of this article (10.1186/s13071-017-2487-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Enock Matovu
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, Kampala, Uganda.
| | - Annah Kitibwa
- College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB), Makerere University, Kampala, Uganda
| | - Albert Picado
- Foundation for Innovative New Diagnostics (FIND), Campus Biotech, Chemin des Mines, Geneva, Switzerland
| | - Sylvain Biéler
- Foundation for Innovative New Diagnostics (FIND), Campus Biotech, Chemin des Mines, Geneva, Switzerland
| | | | - Joseph Mathu Ndung'u
- Foundation for Innovative New Diagnostics (FIND), Campus Biotech, Chemin des Mines, Geneva, Switzerland
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14
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Kozycki CT, Umulisa N, Rulisa S, Mwikarago EI, Musabyimana JP, Habimana JP, Karema C, Krogstad DJ. False-negative malaria rapid diagnostic tests in Rwanda: impact of Plasmodium falciparum isolates lacking hrp2 and declining malaria transmission. Malar J 2017; 16:123. [PMID: 28320390 PMCID: PMC5359811 DOI: 10.1186/s12936-017-1768-1] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 03/08/2017] [Indexed: 11/10/2022] Open
Abstract
Background Rapid diagnostic tests (RDTs) for histidine rich protein 2 (HRP2) are often used to determine whether persons with fever should be treated with anti-malarials. However, Plasmodium falciparum parasites with a deletion of the hrp2 gene yield false-negative RDTs and there are concerns the sensitivity of HRP2-based RDTs may fall when the intensity of transmission decreases. Methods This observational study enrolled 9226 patients at three health centres in Rwanda from April 2014 to April 2015. It then compared the sensitivity of RDTs based on HRP2 and the Plasmodium lactate dehydrogenase (pLDH) to microscopy (thick smears) for the diagnosis of malaria. PCR was used to determine whether deletions of the histidine-rich central repeat region of the hrp2 gene (exon 2) were associated with false-negative HRP2-based RDTs. Results In comparison to microscopy, the sensitivity and specificity of HRP2- and pLDH-based RDTs were 89.5 and 86.2% and 80.2 and 94.3%, respectively. When the results for both RDTs were combined, sensitivity rose to 91.8% and specificity was 85.7%. Additionally, when smear positivity fell from 46 to 3%, the sensitivity of the HRP2-based RDT fell from 88 to 67%. Of 370 samples with false-negative HRP2 RDT results for which PCR was performed, 140 (38%) were identified as P. falciparum by PCR. Of the isolates identified as P. falciparum by PCR, 32 (23%) were negative for the hrp2 gene based on PCR. Of the 32 P. falciparum isolates negative for hrp2 by PCR, 17 (53%) were positive based on the pLDH RDT. Conclusion This prospective study of RDT performance coincided with a decline in the intensity of malaria transmission in Kibirizi (fall in slide positivity from 46 to 3%). This decline was associated with a decrease in HRP2 RDT sensitivity (from 88 to 67%). While P. falciparum isolates without the hrp2 gene were an important cause of false-negative HRP2-based RDTs, most were identified by the pLDH-based RDT. Although WHO does not recommend the use of combined HRP2/pLDH testing in sub-Saharan Africa, these results suggest that combination HRP2/pLDH-based RDTs could reduce the impact of false-negative HRP2-based RDTs for detection of symptomatic P. falciparum malaria. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1768-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Noella Umulisa
- Malaria and Other Parasitic Diseases Division, Rwanda Biomedical Centre, Ministry of Health, Kigali, Rwanda.,Maternal and Child Survival Programme, Jhpiego, Kigali, Rwanda
| | - Stephen Rulisa
- School of Medicine and Pharmacy, University of Rwanda, Kigali, Rwanda
| | - Emil I Mwikarago
- National Reference Laboratory, Rwanda Biomedical Centre, Ministry of Health, Kigali, Rwanda
| | | | - Jean Pierre Habimana
- Malaria and Other Parasitic Diseases Division, Rwanda Biomedical Centre, Ministry of Health, Kigali, Rwanda
| | - Corine Karema
- Malaria and Other Parasitic Diseases Division, Rwanda Biomedical Centre, Ministry of Health, Kigali, Rwanda.,Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland.,Quality and Equity Healthcare, Kigali, Rwanda
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15
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Kemleu S, Guelig D, Eboumbou Moukoko C, Essangui E, Diesburg S, Mouliom A, Melingui B, Manga J, Donkeu C, Epote A, Texier G, LaBarre P, Burton R, Ayong L. A Field-Tailored Reverse Transcription Loop-Mediated Isothermal Assay for High Sensitivity Detection of Plasmodium falciparum Infections. PLoS One 2016; 11:e0165506. [PMID: 27824866 PMCID: PMC5100904 DOI: 10.1371/journal.pone.0165506] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 10/13/2016] [Indexed: 11/19/2022] Open
Abstract
Highly sensitive and field deployable molecular diagnostic tools are critically needed for detecting submicroscopic, yet transmissible levels of malaria parasites prevalent in malaria endemic countries worldwide. A reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed and evaluated in comparison with thick blood smear microscopy, an antigen-based rapid diagnostic test (RDT), and an in-house RT-PCR targeting the same RT-LAMP transcript. The optimized assay detected Plasmodium falciparum infections in as little as 0.25ng of total parasite RNA, and exhibited a detection limit of 0.08 parasites/ μL when tested directly on infected whole blood lysates, or ~0.0008 parasites/ μL when using RNA extracts. Assay positivity was observed as early as eight minutes from initiation of the RT-LAMP and in most cases the reaction was complete before twenty minutes. Clinical evaluation of the assay on 132 suspected malaria cases resulted in a positivity rate of 90% for RT-LAMP using extracted RNA, and 85% when using whole blood lysates. The positivity rates were 70% for P. falciparum-specific RDT, 83% for RT-PCR, and 74% for thick blood smear microscopy (Mean parasite density = 36,986 parasites/ μL). Concordance rates between the developed RT-LAMP and comparator tests were greater than 75%, the lowest being with light microscopy (78%, McNemar's test: P = 0.0002), and the highest was with RT-PCR (87%, McNemar's test: P = 0.0523). Compared to reference RT-PCR, assay sensitivity was 90% for RT-LAMP on whole blood, and 96% for RT-LAMP using corresponding RNA extracts. Electricity-free heaters were further developed and evaluated in comparison with a battery-operated isothermal amplification machine for use with the developed test in resource-limited settings. Taken together, the data highlight the benefits of targeting high abundant RNA transcripts in molecular diagnosis, as well as the potential usefulness of the developed RT-LAMP-assay in malaria diagnosis in low to high parasite density settings.
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Affiliation(s)
- Sylvie Kemleu
- Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Dylan Guelig
- PATH, Seattle, Washington, United States of America
| | - Carole Eboumbou Moukoko
- Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
- Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon
| | - Estelle Essangui
- Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
- Faculty of Sciences, University of Douala, Douala, Cameroon
| | | | - Abas Mouliom
- Hematology Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | | | - Jeanne Manga
- Hematology Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Christiane Donkeu
- Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Annie Epote
- Hematology Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Gaëtan Texier
- Public Health & Epidemiology Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
| | - Paul LaBarre
- PATH, Seattle, Washington, United States of America
| | | | - Lawrence Ayong
- Malaria Research Unit, Centre Pasteur du Cameroun, Yaoundé, Cameroon
- * E-mail:
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Abstract
PURPOSE OF REVIEW Limitations of blood smear microscopy contributed to failure of the 1950-1960s WHO Global Programme to Eliminate Malaria. All diagnostic methods encounter limits of detection (LOD) beyond which it will not be possible to identify infected individuals. When this occurs, it becomes difficult to continue evaluating progress of malaria elimination. The purpose of this review is to compare available diagnostic technologies, factors that underlie their LOD, and their potential roles related to the goal of elimination. RECENT FINDINGS Parasite-containing cells, parasite proteins, hemozoin, nucleic acids, and parasite-specific human antibodies are targets of diagnosis. Many studies report advantages of technologies to detect these diagnostic targets. Nucleic acid amplification tests and strategies for enriching capture of malaria diagnostic targets have consistently identified a parasite reservoir not detected by methods focused on the other biological targets. Exploiting magnetic properties of hemozoin may open new strategies for noninvasive malaria diagnosis. SUMMARY Microscopy and rapid diagnostic tests provide effective surveillance for malaria control. Strategies that detect a reservoir of submicroscopic infection must be developed and standardized to guide malaria elimination.
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Rapid Point-of-Care Diagnosis of Malaria and Dengue Infection. Mol Microbiol 2016. [DOI: 10.1128/9781555819071.ch42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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18
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Molecular Approaches for Diagnosis of Malaria and the Characterization of Genetic Markers for Drug Resistance. Mol Microbiol 2016. [DOI: 10.1128/9781555819071.ch37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Yansouni CP, Merckx J, Libman MD, Ndao M. Recent advances in clinical parasitology diagnostics. Curr Infect Dis Rep 2014; 16:434. [PMID: 25230603 DOI: 10.1007/s11908-014-0434-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Microscopy has several limitations in the diagnosis of parasitic infection. New technologies have emerged to address some of these limitations. We review recent advances in three key areas. The detection of enteric protozoa is a commonly requested test, particularly with increasing travel to and migration from endemic countries. Microscopy is slow and labor intensive and requires a high level of technical expertise. It also lacks both sensitivity and specificity. Recently developed nucleic acid amplification tests are automated and rapid and show superior accuracy. Proteomics shows promise for both the diagnosis of infections where parasite detection is difficult and the potential for accurate assessment of cure in these cases. Finally, rapid and simple diagnostic tests suitable for use in low-resource settings are now allowing for improved study and control of infection in endemic regions.
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Affiliation(s)
- Cedric P Yansouni
- J.D. MacLean Centre for Tropical Diseases, McGill University Health Centre, 1650 Cedar Avenue, Room L10.509, Montreal, H3G 1A4, Canada
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Lejon V, Jacobs J, Simarro PP. Elimination of sleeping sickness hindered by difficult diagnosis. Bull World Health Organ 2014; 91:718. [PMID: 24115791 DOI: 10.2471/blt.13.126474] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Affiliation(s)
- Veerle Lejon
- Institut de Recherche pour le Développement, UMR 177 IRD-CIRAD INTERTRYP, Campus International de Baillarguet TA A-17/G, 34398 Montpellier Cedex 5, France
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A mixed methods study of a health worker training intervention to increase syndromic referral for gambiense human African trypanosomiasis in South Sudan. PLoS Negl Trop Dis 2014; 8:e2742. [PMID: 24651696 PMCID: PMC3961197 DOI: 10.1371/journal.pntd.0002742] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Accepted: 01/31/2014] [Indexed: 11/19/2022] Open
Abstract
Background Active screening by mobile teams is considered the most effective method for detecting gambiense-type human African trypanosomiasis (HAT) but constrained funding in many post-conflict countries limits this approach. Non-specialist health care workers (HCWs) in peripheral health facilities could be trained to identify potential cases for testing based on symptoms. We tested a training intervention for HCWs in peripheral facilities in Nimule, South Sudan to increase knowledge of HAT symptomatology and the rate of syndromic referrals to a central screening and treatment centre. Methodology/Principal Findings We trained 108 HCWs from 61/74 of the public, private and military peripheral health facilities in the county during six one-day workshops and assessed behaviour change using quantitative and qualitative methods. In four months prior to training, only 2/562 people passively screened for HAT were referred from a peripheral HCW (0 cases detected) compared to 13/352 (2 cases detected) in the four months after, a 6.5-fold increase in the referral rate observed by the hospital. Modest increases in absolute referrals received, however, concealed higher levels of referral activity in the periphery. HCWs in 71.4% of facilities followed-up had made referrals, incorporating new and pre-existing ideas about HAT case detection into referral practice. HCW knowledge scores of HAT symptoms improved across all demographic sub-groups. Of 71 HAT referrals made, two-thirds were from new referrers. Only 11 patients completed the referral, largely because of difficulties patients in remote areas faced accessing transportation. Conclusions/Significance The training increased knowledge and this led to more widespread appropriate HAT referrals from a low base. Many referrals were not completed, however. Increasing access to screening and/or diagnostic tests in the periphery will be needed for greater impact on case-detection in this context. These data suggest it may be possible for peripheral HCWs to target the use of rapid diagnostic tests for HAT. Human African trypanosomiasis (HAT or sleeping sickness) is a fatal but treatable disease affecting poor people in sub-Saharan Africa. Most HAT diagnostic equipment, infrastructure and expertise is located in hospitals. The expense of expanding testing services to remote areas using mobile teams severely restricts their use. Non-specialist healthcare workers (HCWs) in first-line (primary) health care facilities can contribute to control by identifying patients in need of testing based on their symptoms. We therefore trained first-line HCWs to recognise potential syndromic cases of HAT and refer them to a hospital screening service. Against a low baseline of HCW HAT referral experience, four months after the intervention, HCW knowledge of HAT symptoms increased and HCWs in 71.4% of facilities across the county had made referrals, incorporating new and pre-existing ideas about HAT case detection into referral practice. There was only a modest increase in numbers of referred patients received at the hospital for screening, however, largely because of distance. In an era where approaches to HAT case detection and control must increasingly be integrated into health referral systems, it is vital to understand the opportunities and challenges associated with syndromic case detection in first line facilities to design effective interventions.
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Djallé D, Gody JC, Moyen JM, Tekpa G, Ipero J, Madji N, Breurec S, Manirakiza A. Performance of Paracheck™-Pf, SD Bioline malaria Ag-Pf and SD Bioline malaria Ag-Pf/pan for diagnosis of falciparum malaria in the Central African Republic. BMC Infect Dis 2014; 14:109. [PMID: 24568311 PMCID: PMC3938899 DOI: 10.1186/1471-2334-14-109] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 02/20/2014] [Indexed: 11/17/2022] Open
Abstract
Background Rapid diagnostic tests (RDTs) are the current complement to microscopy for ensuring prompt malaria treatment. We determined the performance of three candidate RDTs (Paracheck™-Pf, SD Bioline malaria Ag-Pf and SD Bioline malaria Ag-Pf/pan) for rapid diagnosis of malaria in the Central African Republic. Methods Blood samples from consecutive febrile patients who attended for laboratory analysis of malaria at the three main health centres of Bangui were screened by microscopy and the RDTs. Two reference standards were used to assess the performance of the RDTs: microscopy and, a combination of microscopy plus nested PCR for slides reported as negative, on the assumption that negative results by microscopy were due to sub-patent parasitaemia. Results We analysed 436 samples. Using the combined reference standard of microscopy + PCR, the sensitivity of Paracheck™-Pf was 85.7% (95% CI, 80.8–89.8%), that of SD Bioline Ag-Pf was 85.4% (95% CI, 80.5–90.7%), and that of SD Bioline Ag-Pf/pan was 88.2% (95% CI, 83.2–92.0%). The tests performed less well in cases of low parasitaemia; however, the sensitivity was > 95% at > 500 parasites/μl. Conclusions Overall, SD Bioline malaria Ag-Pf and SD Bioline malaria Ag-Pf/pan performed slightly better than Paracheck™-Pf. Use of RDTs with reinforced microscopy practice and laboratory quality assurance should improve malaria treatment in the Central African Republic.
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Maltha J, Guiraud I, Lompo P, Kaboré B, Gillet P, Van Geet C, Tinto H, Jacobs J. Accuracy of PfHRP2 versus Pf-pLDH antigen detection by malaria rapid diagnostic tests in hospitalized children in a seasonal hyperendemic malaria transmission area in Burkina Faso. Malar J 2014; 13:20. [PMID: 24418119 PMCID: PMC3896846 DOI: 10.1186/1475-2875-13-20] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 12/28/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In most sub-Saharan African countries malaria rapid diagnostic tests (RDTs) are now used for the diagnosis of malaria. Most RDTs used detect Plasmodium falciparum histidine-rich protein-2 (PfHRP2), though P. falciparum-specific parasite lactate dehydrogenase (Pf-pLDH)-detecting RDTs may have advantages over PfHRP2-detecting RDTs. Only few data are available on the use of RDTs in severe illness and the present study compared Pf-pLDH to PfHRP2-detection. METHODS Hospitalized children aged one month to 14 years presenting with fever or severe illness were included over one year. Venous blood samples were drawn for malaria diagnosis (microscopy and RDT), culture and complete blood count. Leftovers were stored at -80 °C and used for additional RDT analysis and PCR. An RDT targeting both PfHRP2 and Pf-pLDH was performed on all samples for direct comparison of diagnostic accuracy with microscopy as reference method. PCR was performed to explore false-positive RDT results. RESULTS In 376 of 694 (54.2%) included children, malaria was microscopically confirmed. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value were 100.0, 70.9, 69.4 and 100.0%, respectively for PfHRP2-detection and 98.7, 94.0, 91.6 and 99.1%, respectively for Pf-pLDH-detection. Specificity and PPV were significantly lower for PfHRP2-detection (p <0.001). For both detection antigens, specificity was lowest for children one to five years and in the rainy season. PPV for both antigens was highest in the rainy season, because of higher malaria prevalence. False positive PfHRP2 results were associated with prior anti-malarial treatment and positive PCR results (98/114 (86.0%) samples tested). CONCLUSION Among children presenting with severe febrile illness in a seasonal hyperendemic malaria transmission area, the present study observed similar sensitivity but lower specificity and PPV of PfHRP2 compared to Pf-pLDH-detection. Further studies should assess the diagnostic accuracy and safety of an appropriate Pf-pLDH-detecting RDT in field settings and if satisfying, replacement of PfHRP2 by Pf-pLDH-detecting RDTs should be considered.
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Affiliation(s)
- Jessica Maltha
- Department of Clinical Sciences, Institute of Tropical Medicine, Nationalestraat 155, B 2000, Antwerp, Belgium.
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Mitashi P, Hasker E, Ngoyi DM, Pyana PP, Lejon V, Van der Veken W, Lutumba P, Büscher P, Boelaert M, Deborggraeve S. Diagnostic accuracy of loopamp Trypanosoma brucei detection kit for diagnosis of human African trypanosomiasis in clinical samples. PLoS Negl Trop Dis 2013; 7:e2504. [PMID: 24147176 PMCID: PMC3798548 DOI: 10.1371/journal.pntd.0002504] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 09/11/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Molecular methods have great potential for sensitive parasite detection in the diagnosis of human African trypanosomiasis (HAT), but the requirements in terms of laboratory infrastructure limit their use to reference centres. A recently developed assay detects the Trypanozoon repetitive insertion mobile element (RIME) DNA under isothermal amplification conditions and has been transformed into a ready-to-use kit format, the Loopamp Trypanosoma brucei. In this study, we have evaluated the diagnostic performance of the Loopamp Trypanosoma brucei assay (hereafter called LAMP) in confirmed T.b. gambiense HAT patients, HAT suspects and healthy endemic controls from the Democratic Republic of the Congo (DRC). METHODOLOGY/PRINCIPAL FINDINGS 142 T.b. gambiense HAT patients, 111 healthy endemic controls and 97 HAT suspects with unconfirmed status were included in this retrospective evaluation. Reference standard tests were parasite detection in blood, lymph or cerebrospinal fluid. Archived DNA from blood of all study participants was analysed in duplicate with LAMP. Sensitivity of LAMP in parasitologically confirmed cases was 87.3% (95% CI 80.9-91.8%) in the first run and 93.0% (95% CI 87.5-96.1%) in the second run. Specificity in healthy controls was 92.8% (95% CI 86.4-96.3%) in the first run and 96.4% (95% CI 91.1-98.6%) in the second run. Reproducibility was excellent with a kappa value of 0.81. CONCLUSIONS/SIGNIFICANCE In this laboratory-based study, the Loopamp Trypanosoma brucei Detection Kit showed good diagnostic accuracy and excellent reproducibility. Further studies are needed to assess the feasibility of its routine use for diagnosis of HAT under field conditions.
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Affiliation(s)
- Patrick Mitashi
- Institute of Tropical Medicine, Antwerp, Belgium
- Faculty of Medicine, Kinshasa University, Kinshasa, Democratic Republic of the Congo
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of the Congo
| | - Epco Hasker
- Institute of Tropical Medicine, Antwerp, Belgium
| | - Dieudonné Mumba Ngoyi
- Faculty of Medicine, Kinshasa University, Kinshasa, Democratic Republic of the Congo
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of the Congo
| | - Pati Patient Pyana
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of the Congo
| | - Veerle Lejon
- Institute of Tropical Medicine, Antwerp, Belgium
| | - Wim Van der Veken
- Belgian Development Agency, Kinshasa, Democratic Republic of the Congo
| | - Pascal Lutumba
- Faculty of Medicine, Kinshasa University, Kinshasa, Democratic Republic of the Congo
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of the Congo
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Fançony C, Sebastião YV, Pires JE, Gamboa D, Nery SV. Performance of microscopy and RDTs in the context of a malaria prevalence survey in Angola: a comparison using PCR as the gold standard. Malar J 2013; 12:284. [PMID: 23941281 PMCID: PMC3751255 DOI: 10.1186/1475-2875-12-284] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 08/02/2013] [Indexed: 11/30/2022] Open
Abstract
Background Accurate identification of Plasmodium infections in community surveys is essential to successful malaria control. Microscopy and rapid diagnostic tests (RDTs) are the main techniques used to diagnose malaria in field-based surveys. While microscopy is still considered the gold standard, RDTs are growing in popularity as they allow for rapid and inexpensive diagnosis. Using data from a prevalence survey conducted in north-western Angola in 2010, the authors aimed to compare the performance of microscopy and RDTs in identifying Plasmodium falciparum infections, using polymerase chain reaction (PCR) as the gold standard. Methods Results from 3,307 subjects (1,225 preschool-aged children (zero to five year olds), 1,134 school-aged children (six to 15 year olds) and 948 mothers/caregivers (>15 years of age)), tested for P. falciparum infections, were utilized. The sensitivity, specificity, positive, and negative predictive values (PPV and NPV) of microscopy and Paracheck-Pf® were compared using the McNemar’s test and the weighted generalized score Chi-squared test for paired data. Results The prevalence of P. falciparum infections determined by PCR and microscopy was 15.9% and by Paracheck- Pf® was 16.3%. Compared to microscopy, Paracheck-Pf® had significantly higher sensitivity (72.8% versus 60%), specificity (94.3% versus 92.5%), PPV (70.7% versus 60%) and NPV (94.8% versus 92.5%). Both tests had significantly lower sensitivity in mothers (36.8% for microscopy and 43.7% for Paracheck-Pf®) than in their children (68.4% in zero to five years-old and 60.6% in six to 15 years-old for microscopy and 80.4% in zero to five year-olds and 76.5% in six to 15 year-olds for Paracheck-Pf®). Conclusion Both microscopy and RDTs performed suboptimally when compared to PCR. False negativity could be associated with the low parasite density profile of the samples. False positivity may be related to the well-described limitations of those techniques such as level of expertise of microscopists or persistent antigenicity from previous infections in the case of RDTs. Nevertheless, RDTs had enhanced performance comparatively to microscopy in detecting malaria infections, favouring their use in community cross-sectional malaria surveys, where expert performance of microscopy is hard to accomplish.
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