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Amaral PST, Garcia KKS, Suárez-Mutis MC, Coelho RR, Galardo AK, Murta F, Moresco GG, Siqueira AM, Gurgel-Gonçalves R. Malaria in areas under mining activity in the Amazon: A review. Rev Soc Bras Med Trop 2024; 57:e002002024. [PMID: 38922216 DOI: 10.1590/0037-8682-0551-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Accepted: 05/09/2024] [Indexed: 06/27/2024] Open
Abstract
Deforestation and high human mobility due to mining activities have been key to the increase in malaria cases in the Americas. Here, we review the epidemiological and control aspects of malaria in the Amazon mining areas. Epidemiological evidence shows: 1) a positive correlation between illegal mining activity and malaria incidence, mostly in the Amazon region; 2) most Brazilian miners are males aged 15-29 years who move between states and even countries; 3) miners do not fear the disease and rely on medical care, diagnosis, and medication when they become ill; 4) illegal mining has emerged as the most reported anthropogenic activity within indigenous lands and is identified as a major cause of malaria outbreaks among indigenous people in the Amazon; and 5) because mining is largely illegal, most areas are not covered by any healthcare facilities or activities, leading to little assistance in the diagnosis and treatment of malaria. Our review identified five strategies for reducing the malaria incidence in areas with mining activities: 1) reviewing legislation to control deforestation and mining expansion, particularly in indigenous lands; 2) strengthening malaria surveillance by expanding the network of community health agents to support rapid diagnosis and treatment; 3) reinforcing vector control strategies, such as the use of insecticide-treated nets; 4) integrating deforestation alerts into the national malaria control program; and 5) implementing multi-sectoral activities and providing prompt assistance to indigenous populations. With this roadmap, we can expect a decrease in malaria incidence in the Amazonian mining areas in the future.
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Affiliation(s)
- Pablo Sebastian Tavares Amaral
- Universidade de Brasília, Faculdade de Medicina, Programa de Pós-graduação em Medicina Tropical, Brasília, DF, Brasil
- Secretaria de Vigilância em Saúde e Ambiente, Ministério da Saúde, Brasília, DF, Brasil
| | - Klauss Kleydmann Sabino Garcia
- Universidade de Brasília, Faculdade de Medicina, Programa de Pós-graduação em Medicina Tropical, Brasília, DF, Brasil
- Secretaria de Vigilância em Saúde e Ambiente, Ministério da Saúde, Brasília, DF, Brasil
- Universidade de Brasília, Faculdade de Ciências da Saúde, Brasília, DF, Brasil
| | | | - Ronan Rocha Coelho
- Secretaria de Vigilância em Saúde e Ambiente, Ministério da Saúde, Brasília, DF, Brasil
| | - Allan Kardec Galardo
- Laboratório de Entomologia Médica, Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá, Macapá, AP, Brasil
| | - Felipe Murta
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Departamento de Ensino e Pesquisa, Manaus, AM, Brasil
| | - Gilberto Gilmar Moresco
- Secretaria de Vigilância em Saúde e Ambiente, Ministério da Saúde, Brasília, DF, Brasil
- Universidade de Brasília, Faculdade de Ciências da Saúde, Programa de Pós-graduação em Saúde Coletiva, Brasília, DF, Brasil
| | - André Machado Siqueira
- Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil
| | - Rodrigo Gurgel-Gonçalves
- Universidade de Brasília, Faculdade de Medicina, Laboratório de Parasitologia Médica e Biologia Vetores, Brasília, DF, Brasil
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Kim H, Tak S, Lee SD, Park S, Hwang K. Factors associated with the timely diagnosis of malaria and the utilization of types of healthcare facilities: a retrospective study in the Republic of Korea. Osong Public Health Res Perspect 2024; 15:159-167. [PMID: 38621761 PMCID: PMC11082442 DOI: 10.24171/j.phrp.2023.0349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/08/2024] [Accepted: 01/18/2024] [Indexed: 04/17/2024] Open
Abstract
BACKGROUND This study aimed to analyze trends in the timely diagnosis of malaria cases over the past 10 years in relation to the utilization of different types of healthcare facilities. METHODS The study included 3,697 confirmed and suspected cases of malaria reported between January 1, 2013, and December 31, 2022, in the national integrative disease and healthcare management system. Some cases lacking a case report or with information missing from the case report were excluded from the analysis. A generalized linear model with a Poisson distribution was constructed to estimate risk ratios and 95% confidence intervals adjusted for other variables, such as distance. RESULTS When cases involving diagnosis >5 days after symptom onset in confirmed patients (5DD) were examined according to the type of healthcare facility, the risk ratio of 5DD cases was found to be higher for tertiary hospitals than for public health facilities. Specifically, the risk ratio was higher when the diagnosis was established at a tertiary hospital, even after a participant had visited primary or secondary hospitals. In an analysis adjusted for the distance to each participant's healthcare facility, the results did not differ substantially from the results of the crude analysis. CONCLUSION It is imperative to improve the diagnostic capabilities of public facilities and raise awareness of malaria at primary healthcare facilities for effective prevention and control.
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Affiliation(s)
- HyunJung Kim
- Division of Control for Zoonotic and Vector Borne Disease, Bureau of Infectious Disease Policy, Korea Disease Control and Prevention Agency, Cheongju, Republic of Korea
| | - Sangwoo Tak
- Division of Risk Assessment, Bureau of Public Health Emergency Preparedness, Korea Disease Control and Prevention Agency, Cheongju, Republic of Korea
| | - So-dam Lee
- Division of Control for Zoonotic and Vector Borne Disease, Bureau of Infectious Disease Policy, Korea Disease Control and Prevention Agency, Cheongju, Republic of Korea
| | - Seongwoo Park
- Division of Control for Zoonotic and Vector Borne Disease, Bureau of Infectious Disease Policy, Korea Disease Control and Prevention Agency, Cheongju, Republic of Korea
| | - Kyungwon Hwang
- Division of Control for Zoonotic and Vector Borne Disease, Bureau of Infectious Disease Policy, Korea Disease Control and Prevention Agency, Cheongju, Republic of Korea
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Omorou R, Delabie B, Lavoignat A, Chaker V, Bonnot G, Traore K, Bienvenu AL, Picot S. Nanoparticle tracking analysis of natural hemozoin from Plasmodium parasites. Acta Trop 2024; 250:107105. [PMID: 38135133 DOI: 10.1016/j.actatropica.2023.107105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 12/24/2023]
Abstract
BACKGROUND Hemozoin is a byproduct of hemoglobin digestion crucial for parasite survival. It forms crystals that can be of interest as drug targets or biomarkers of malaria infection. However, hemozoin has long been considered as an amorphous crystal of simple morphology. Studying the consequences of biomineralization of this crystal during the parasite growth may provide more comprehensive evidence of its role during malaria. OBJECTIVES This study aimed to investigate the interest of nanoparticles tracker analysis for measuring the concentration and size of hemozoin particles produced from different parasite sources and conditions. METHODS Hemozoin was extracted from several clones of Plasmodium falciparum both asexual and sexual parasites. Hemozoin was also extracted from blood samples of malaria patients and from saliva of asymptomatic malaria carriers. Nanoparticles tracking analysis (NTA) was performed to assess the size and concentration of hemozoin. RESULTS NTA data showed variation in hemozoin concentration, size, and crystal clusters between parasite clones, species, and stages. Among parasite clones, hemozoin concentration ranged from 131 to 2663 particles/infected red blood cell (iRBC) and size ranged from 149.6 ± 6.3 nm to 234.8 ± 40.1 nm. The mean size was lower for Plasmodium vivax (176 ± 79.2 nm) than for Plasmodium falciparum (254.8 ± 74.0 nm). Sexual NF54 parasites showed a 7.5-fold higher concentration of hemozoin particles (28.7 particles/iRBC) compared to asexual parasites (3.8 particles/iRBC). In addition, the mean hemozoin size also increased by approximately 60 % for sexual parasites. Compared to in vitro cultures of parasites, blood samples showed low hemozoin concentrations. CONCLUSIONS This study highlights the potential of NTA as a useful method for analyzing hemozoin, demonstrating its ability to provide detailed information on hemozoin characterization. However, further research is needed to adapt the NTA for hemozoin analysis.
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Affiliation(s)
- Roukayatou Omorou
- Malaria Research Unit, UMR 5246 CNRS-INSA-CPE, University Lyon1, University Lyon, Villeurbanne 69100, France.
| | - Blanche Delabie
- Malaria Research Unit, UMR 5246 CNRS-INSA-CPE, University Lyon1, University Lyon, Villeurbanne 69100, France
| | - Adeline Lavoignat
- Malaria Research Unit, UMR 5246 CNRS-INSA-CPE, University Lyon1, University Lyon, Villeurbanne 69100, France
| | - Victorien Chaker
- Malaria Research Unit, UMR 5246 CNRS-INSA-CPE, University Lyon1, University Lyon, Villeurbanne 69100, France
| | - Guillaume Bonnot
- Malaria Research Unit, UMR 5246 CNRS-INSA-CPE, University Lyon1, University Lyon, Villeurbanne 69100, France
| | - Karim Traore
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Anne-Lise Bienvenu
- Malaria Research Unit, UMR 5246 CNRS-INSA-CPE, University Lyon1, University Lyon, Villeurbanne 69100, France; Service Pharmacie, Groupement Hospitalier Nord, Hospices Civils de Lyon, Lyon 69004, France
| | - Stephane Picot
- Malaria Research Unit, UMR 5246 CNRS-INSA-CPE, University Lyon1, University Lyon, Villeurbanne 69100, France; Institute of Parasitology and Medical Mycology, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon 69004, France
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Shears MJ, Reynolds RA, Duncombe CJ, Watson FN, Staubus WJ, Chavtur C, Seilie AM, Tran TM, Chakravarty S, Hoffman SL, Murphy SC. Plasmodium knowlesi in pig-tailed macaques: a potential new model for malaria vaccine research. Malar J 2023; 22:379. [PMID: 38093306 PMCID: PMC10720125 DOI: 10.1186/s12936-023-04788-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 11/11/2023] [Indexed: 12/17/2023] Open
Abstract
BACKGROUND Plasmodium knowlesi is an established experimental model for basic and pre-clinical malaria vaccine research. Historically, rhesus macaques have been the most common host for malaria vaccine studies with P. knowlesi parasites. However, rhesus are not natural hosts for P. knowlesi, and there is interest in identifying alternative hosts for vaccine research. The study team previously reported that pig-tailed macaques (PTM), a natural host for P. knowlesi, could be challenged with cryopreserved P. knowlesi sporozoites (PkSPZ), with time to blood stage infection equivalent to in rhesus. Here, additional exploratory studies were performed to evaluate PTM as potential hosts for malaria vaccine studies. The aim was to further characterize the parasitological and veterinary health outcomes after PkSPZ challenge in this macaque species. METHODS Malaria-naïve PTM were intravenously challenged with 2.5 × 103 PkSPZ and monitored for blood stage infection by Plasmodium 18S rRNA RT-PCR and thin blood smears. Disease signs were evaluated by daily observations, complete blood counts, serum chemistry tests, and veterinary examinations. After anti-malarial drug treatment, a subset of animals was re-challenged and monitored as above. Whole blood gene expression analysis was performed on selected animals to assess host response to infection. RESULTS In naïve animals, the kinetics of P. knowlesi blood stage replication was reproducible, with parasite burden rising linearly during an initial acute phase of infection from 6 to 11 days post-challenge, before plateauing and transitioning into a chronic low-grade infection. After re-challenge, infections were again reproducible, but with lower blood stage parasite densities. Clinical signs of disease were absent or mild and anti-malarial treatment was not needed until the pre-defined study day. Whole blood gene expression analysis identified immunological changes associated with acute and chronic phases of infection, and further differences between initial challenge versus re-challenge. CONCLUSIONS The ability to challenge PTM with PkSPZ and achieve reliable blood stage infections indicate this model has significant potential for malaria vaccine studies. Blood stage P. knowlesi infection in PTM is characterized by low parasite burdens and a benign disease course, in contrast with the virulent P. knowlesi disease course commonly reported in rhesus macaques. These findings identify new opportunities for malaria vaccine research using this natural host-parasite combination.
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Affiliation(s)
- Melanie J Shears
- Department of Laboratory Medicine and Pathology, University of Washington, 750 Republican Street, F870, Seattle, WA, 98109, USA
- Center for Emerging and Re-Emerging Infectious Diseases, University of Washington, 750 Republican Street, Seattle, WA, 98109, USA
- Washington National Primate Research Center, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98195, USA
| | - Rebekah A Reynolds
- Department of Laboratory Medicine and Pathology, University of Washington, 750 Republican Street, F870, Seattle, WA, 98109, USA
- Center for Emerging and Re-Emerging Infectious Diseases, University of Washington, 750 Republican Street, Seattle, WA, 98109, USA
| | - Caroline J Duncombe
- Department of Laboratory Medicine and Pathology, University of Washington, 750 Republican Street, F870, Seattle, WA, 98109, USA
- Center for Emerging and Re-Emerging Infectious Diseases, University of Washington, 750 Republican Street, Seattle, WA, 98109, USA
| | - Felicia N Watson
- Department of Laboratory Medicine and Pathology, University of Washington, 750 Republican Street, F870, Seattle, WA, 98109, USA
- Center for Emerging and Re-Emerging Infectious Diseases, University of Washington, 750 Republican Street, Seattle, WA, 98109, USA
| | - Weston J Staubus
- Department of Laboratory Medicine and Pathology, University of Washington, 750 Republican Street, F870, Seattle, WA, 98109, USA
- Center for Emerging and Re-Emerging Infectious Diseases, University of Washington, 750 Republican Street, Seattle, WA, 98109, USA
| | - Chris Chavtur
- Department of Laboratory Medicine and Pathology, University of Washington, 750 Republican Street, F870, Seattle, WA, 98109, USA
- Center for Emerging and Re-Emerging Infectious Diseases, University of Washington, 750 Republican Street, Seattle, WA, 98109, USA
| | - Annette M Seilie
- Department of Laboratory Medicine and Pathology, University of Washington, 750 Republican Street, F870, Seattle, WA, 98109, USA
- Center for Emerging and Re-Emerging Infectious Diseases, University of Washington, 750 Republican Street, Seattle, WA, 98109, USA
| | - Tuan M Tran
- Division of Infectious Diseases, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Sumana Chakravarty
- Sanaria, Inc., 9800 Medical Center Drive, Suite A209, Rockville, MD, 20850, USA
| | - Stephen L Hoffman
- Sanaria, Inc., 9800 Medical Center Drive, Suite A209, Rockville, MD, 20850, USA
| | - Sean C Murphy
- Department of Laboratory Medicine and Pathology, University of Washington, 750 Republican Street, F870, Seattle, WA, 98109, USA.
- Center for Emerging and Re-Emerging Infectious Diseases, University of Washington, 750 Republican Street, Seattle, WA, 98109, USA.
- Washington National Primate Research Center, University of Washington, 1959 NE Pacific Street, Seattle, WA, 98195, USA.
- Department of Microbiology, University of Washington, 750 Republican Street, F870, Seattle, WA, 98109, USA.
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Paper functionalization for detection of Plasmodium falciparum DNA using square waves voltammetry. Talanta 2023; 252:123839. [DOI: 10.1016/j.talanta.2022.123839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 08/08/2022] [Accepted: 08/11/2022] [Indexed: 11/18/2022]
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Awosolu OB, Yahaya ZS, Farah Haziqah MT, Olusi TA. Performance Evaluation of Nested Polymerase Chain Reaction (Nested PCR), Light Microscopy, and Plasmodium falciparum Histidine-Rich Protein 2 Rapid Diagnostic Test (PfHRP2 RDT) in the Detection of Falciparum Malaria in a High-Transmission Setting in Southwestern Nigeria. Pathogens 2022; 11:1312. [PMID: 36365063 PMCID: PMC9694681 DOI: 10.3390/pathogens11111312] [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: 09/17/2022] [Revised: 11/01/2022] [Accepted: 11/02/2022] [Indexed: 09/16/2023] Open
Abstract
Malaria remains a major public health challenge worldwide. In order to ensure a prompt and accurate malaria diagnosis, the World Health Organization recommended the confirmatory parasitological diagnosis of malaria by microscopy and malaria rapid diagnostic test (RDT) prior to antimalarial administration and treatment. This study was designed to evaluate the performance of nested polymerase chain reaction (nested PCR), light microscopy, and Plasmodium falciparum histidine-rich protein 2 rapid diagnostic test (PfHRP2 RDT) in the detection of falciparum malaria in Akure, Nigeria. A cross-sectional and hospital-based study involving 601 febrile volunteer participants was conducted in Akure, Nigeria. Approximately 2-3 mL venous blood samples were obtained from each study participant for parasitological confirmation by microscopy and PfHRP2-based malaria RDT. Thick and thin films were prepared and viewed under the light microscope for parasite detection, parasite density quantification, and species identification, respectively. Dry blood spot samples were prepared on 3MM Whatman filter paper for nested PCR. The overall prevalence of microscopy, PfHRP2 RDT, and nested PCR were 64.89% (390/601), 65.7% (395/601), and 67.39% (405/601), respectively. The estimates of sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and Youden's j index of microscopy and RDT were 96.30, 100.00, 100.00, 92.89, 97.50, 0.963, and 95.06, 94.90, 97.47, 90.29, 95.01, and 0.899, respectively. Malaria RDT recorded higher false negativity, compared microscopy (4.94% vs. 3.70%). A near perfect agreement was reported between microscopy and nested PCR, and between PfHRP2 RDT and nested PCR with Cohen's kappa (k) values of 0.94 and 0.88, respectively. This study revealed that PfHRP2 RDT and microscopy continues to remain sensitive and specific for falciparum malaria diagnosis in the study area.
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Affiliation(s)
- Oluwaseun Bunmi Awosolu
- School of Biological Sciences, Universiti Sains Malaysia, Penang 11800, Malaysia
- Vector Control Research Unit, Universiti Sains Malaysia, Minden, Penang 11800, Malaysia
- Department of Biology, Federal University of Technology, Akure 340252, Nigeria
| | - Zary Shariman Yahaya
- School of Biological Sciences, Universiti Sains Malaysia, Penang 11800, Malaysia
- Vector Control Research Unit, Universiti Sains Malaysia, Minden, Penang 11800, Malaysia
| | | | - Titus Adeniyi Olusi
- Vector Control Research Unit, Universiti Sains Malaysia, Minden, Penang 11800, Malaysia
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Kagaya W, Takehara I, Kurihara K, Maina M, Chan CW, Okomo G, Kongere J, Gitaka J, Kaneko A. Potential application of the haematology analyser XN-31 prototype for field malaria surveillance in Kenya. Malar J 2022; 21:252. [PMID: 36050757 PMCID: PMC9434510 DOI: 10.1186/s12936-022-04259-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 08/09/2022] [Indexed: 11/10/2022] Open
Abstract
Background Simple and accurate diagnosis is a key component of malaria control programmes. Microscopy is the current gold standard, however it requires extensive training and the results largely rely on the skill of the microscopists. Malaria rapid diagnostic tests (RDT) can be performed with minimal training and offer timely diagnosis, but results are not quantitative. Moreover, some Plasmodium falciparum parasites have evolved and can no longer be detected by existing RDT. Developed by the Sysmex Corporation, the XN-31 prototype (XN-31p) is an automated haematology analyser capable of detecting Plasmodium-infected erythrocytes and providing species differentiation and stage specific parasite counts in venous blood samples without any preparation in approximately one minute. However, factors such as stable electricity supply in a temperature-controlled room, cost of the instrument and its initial set-up, and need for proprietary reagents limit the utility of the XN-31p across rural settings. To overcome some of these limitations, a hub and spoke diagnosis model was designed, in which peripheral health facilities were linked to a central hospital where detection of Plasmodium infections by the XN-31p would take place. To explore the feasibility of this concept, the applicability of capillary blood samples with the XN-31p was evaluated with respect to the effect of sample storage time and temperature on the stability of results. Methods Paired capillary and venous blood samples were collected from 169 malaria-suspected outpatients in Homa Bay County Referral Hospital, Kenya. Malaria infections were diagnosed with the XN-31p, microscopy, RDT, and PCR. Capillary blood samples were remeasured on the XN-31p after 24 h of storage at either room (15–25 °C) or chilled temperatures (2–8 °C). Results Identical results in malaria diagnosis were observed between venous and capillary blood samples processed immediately after collection with the XN-31p. Relative to PCR, the sensitivity and specificity of the XN-31p with capillary blood samples were 0.857 and 1.000, respectively. Short-term storage of capillary blood samples at chilled temperatures had no adverse impact on parasitaemia and complete blood counts (CBC) measured by the XN-31p. Conclusion These results demonstrate the potential of the XN-31p to improve routine malaria diagnosis across remote settings using a hub and spoke model. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04259-7.
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Affiliation(s)
- Wataru Kagaya
- Department of Virology and Parasitology/Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, 1-4-3, Asahimachi, Abeno-ku, Osaka, 545-8585, Japan.,Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, NagasakiNagasaki, 852-8523, Japan
| | - Ikki Takehara
- Sysmex Corporation, 4-4-4 Takatsukadai, Nishiku, Kobe, Hyogo, 651-2271, Japan
| | - Kyoko Kurihara
- Sysmex Corporation, 4-4-4 Takatsukadai, Nishiku, Kobe, Hyogo, 651-2271, Japan
| | - Michael Maina
- Department of Clinical Medicine, Mount Kenya University, PO Box 342-01000, Thika, Kenya
| | - Chim W Chan
- Department of Virology and Parasitology/Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, 1-4-3, Asahimachi, Abeno-ku, Osaka, 545-8585, Japan
| | | | - James Kongere
- Nairobi Research Station, Nagasaki University Institute of Tropical Medicine-Kenya Medical Research Institute (NUITM-KEMRI) Project, Institute of Tropical Medicine (NEKKEN), Nagasaki University, PO Box 19993-00202, Nairobi, Kenya.,Department of Virology and Parasitology, Graduate School of Medicine, Osaka Metropolitan University, 1-4-3, Asahimachi, Abeno-ku, Osaka, 545-8585, Japan
| | - Jesse Gitaka
- Department of Clinical Medicine, Mount Kenya University, PO Box 342-01000, Thika, Kenya.,Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, NagasakiNagasaki, 852-8523, Japan.,Centre for Malaria Elimination, Mount Kenya University, P.O. Box 342-01000, Thika, Kenya
| | - Akira Kaneko
- Department of Virology and Parasitology/Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka Metropolitan University, 1-4-3, Asahimachi, Abeno-ku, Osaka, 545-8585, Japan. .,Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, NagasakiNagasaki, 852-8523, Japan. .,Island Malaria Group, Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Biomedicum, Solnavägen 9, Solna, 171 65, Stockholm, Sweden.
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Picot S, Perpoint T, Chidiac C, Sigal A, Javouhey E, Gillet Y, Jacquin L, Douplat M, Tazarourte K, Argaud L, Wallon M, Miossec C, Bonnot G, Bienvenu AL. Diagnostic accuracy of fluorescence flow-cytometry technology using Sysmex XN-31 for imported malaria in a non-endemic setting. Parasite 2022; 29:31. [PMID: 35638753 PMCID: PMC9153516 DOI: 10.1051/parasite/2022031] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 05/16/2022] [Indexed: 11/16/2022] Open
Abstract
Malaria diagnosis based on microscopy is impaired by the gradual disappearance of experienced microscopists in non-endemic areas. Aside from the conventional diagnostic methods, fluorescence flow cytometry technology using Sysmex XN-31, an automated haematology analyser, has been registered to support malaria diagnosis. The aim of this prospective, monocentric, non-interventional study was to evaluate the diagnostic accuracy of the XN-31 for the initial diagnosis or follow-up of imported malaria cases compared to the reference malaria tests including microscopy, loop mediated isothermal amplification, and rapid diagnostic tests. Over a one-year period, 357 blood samples were analysed, including 248 negative and 109 positive malaria samples. Compared to microscopy, XN-31 showed sensitivity of 100% (95% CI: 97.13–100) and specificity of 98.39% (95% CI: 95.56–100) for the initial diagnosis of imported malaria cases. Moreover, it provided accurate species identification asfalciparumor non-falciparumand parasitaemia determination in a very short time compared to other methods. We also demonstrated that XN-31 was a reliable method for patient follow-up on days 3, 7, and 28. Malaria diagnosis can be improved in non-endemic areas by the use of dedicated haematology analysers coupled with standard microscopy or other methods in development, such as artificial intelligence for blood slide reading. Given that XN-31 provided an accurate diagnosis in 1 min, it may reduce the time interval before treatment and thus improve the outcome of patient who have malaria.
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Affiliation(s)
- Stéphane Picot
- Service de Parasitologie et Mycologie Médicale, Groupement Hospitalier Nord, Hospices Civils de Lyon,69004 Lyon,France - Université de Lyon, Université Lyon 1, CNRS, INSA, CPE-Lyon, ICBMS, UMR 5246,69100 Villeurbanne,France
| | - Thomas Perpoint
- Service des Maladies Infectieuses et Tropicales, Hôpital de la Croix-Rousse, Hospices Civils de Lyon,69004 Lyon,France
| | - Christian Chidiac
- Service des Maladies Infectieuses et Tropicales, Hôpital de la Croix-Rousse, Hospices Civils de Lyon,69004 Lyon,France - CIRI Équipe PH3ID - INSERM - U1111- UCBL Lyon 1 - CNRS - UMR5308 - ENS de Lyon,69007 Lyon,France
| | - Alain Sigal
- Service d'accueil des urgences, Hôpital de la Croix-Rousse, Hospices Civils de Lyon,69004 Lyon,France
| | - Etienne Javouhey
- Service de Réanimation et Urgences Pédiatriques, Hôpital Femme-Mere-Enfant, Hospices Civils de Lyon,69500 Lyon,France
| | - Yves Gillet
- Service de Réanimation et Urgences Pédiatriques, Hôpital Femme-Mere-Enfant, Hospices Civils de Lyon,69500 Lyon,France
| | - Laurent Jacquin
- Service d'accueil des urgences, Hôpital Edouard Herriot, Hospices Civils de Lyon,69008 Lyon,France
| | - Marion Douplat
- Service d'accueil des urgences, Hôpital Lyon Sud, Hospices Civils de Lyon,69310 Lyon,France - Université de Lyon, Université Claude Bernard Lyon 1, HESPER EA 7425,69008 Lyon,France
| | - Karim Tazarourte
- Service d'accueil des urgences, Hôpital Edouard Herriot, Hospices Civils de Lyon,69008 Lyon,France - Université de Lyon, Université Claude Bernard Lyon 1, HESPER EA 7425,69008 Lyon,France
| | - Laurent Argaud
- Hospices Civils de Lyon, Hôpital Edouard Herriot, Service de Médecine Intensive-Réanimation,69008 Lyon,France
| | - Martine Wallon
- Service de Parasitologie et Mycologie Médicale, Groupement Hospitalier Nord, Hospices Civils de Lyon,69004 Lyon,France
| | - Charline Miossec
- Service de Parasitologie et Mycologie Médicale, Groupement Hospitalier Nord, Hospices Civils de Lyon,69004 Lyon,France
| | - Guillaume Bonnot
- Université de Lyon, Université Lyon 1, CNRS, INSA, CPE-Lyon, ICBMS, UMR 5246,69100 Villeurbanne,France
| | - Anne-Lise Bienvenu
- Université de Lyon, Université Lyon 1, CNRS, INSA, CPE-Lyon, ICBMS, UMR 5246,69100 Villeurbanne,France - Service Pharmacie, Groupement Hospitalier Nord, Hospices Civils de Lyon,69004 Lyon,France
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Costa GL, Alvarenga DAM, Aguiar ACC, Louzada J, Pereira DB, de Oliveira TF, Fonseca Júnior AA, Carvalho LH, Ferreira Alves de Brito C, Nóbrega de Sousa T. Improving the Molecular Diagnosis of Malaria: Droplet Digital PCR-Based Method Using Saliva as a DNA Source. Front Microbiol 2022; 13:882530. [PMID: 35633683 PMCID: PMC9136408 DOI: 10.3389/fmicb.2022.882530] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/20/2022] [Indexed: 12/20/2022] Open
Abstract
Malaria is an acute febrile disease caused by a protozoan of the genus Plasmodium. Light microscopy (LM) is the gold standard for the diagnosis of malaria. Despite this method being rapid and inexpensive, it has a low limit of detection, which hampers the identification of low parasitemia infections. By using multicopy targets and highly sensitive molecular techniques, it is possible to change this scenario. In this study, we evaluated the performance of droplet digital PCR (ddPCR) to detect Plasmodium DNA obtained from saliva samples (whole saliva and buccal swab) of 157 individuals exposed to malaria transmission from the Brazilian Amazon region. We used the highly sensitive ddPCR method with non-ribosomal multicopy targets for Plasmodium vivax (Pvr47) and Plasmodium falciparum (Pfr364). There was good concordance between the quantitative real-time PCR (qPCR) results from the saliva and blood, except for mixed-species infections. The sensitivity of qPCR was 93% for blood, 77% for saliva, and 47% for swabs. Parasite DNA was not detected in saliva samples in low-density infections compared with the detection in blood samples. ddPCR showed increased sensitivity for detecting Plasmodium in the blood and swabs (99% in blood, 73% in saliva, and 59% in swabs). Notably, ddPCR detected more mixed infections in the blood (15%), saliva (9%), and swabs (18%) than qPCR. Our data showed that the differences between ddPCR and qPCR were the result of a higher number of P. falciparum infections detected by ddPCR. Overall, there was a moderate correlation between parasite densities estimated by the different methods in the blood. Our findings highlight the possibility of using non-invasive sample collection methods for malaria diagnosis by targeting multicopy sequences combined with highly sensitive molecular methods.
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Affiliation(s)
- Gabriel Luíz Costa
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Brazil
| | - Denise Anete Madureira Alvarenga
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Brazil
| | | | - Jaime Louzada
- Health Sciences Center, Federal University of Roraima, Boa Vista, Brazil
| | | | | | | | - Luzia Helena Carvalho
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Brazil
| | - Cristiana Ferreira Alves de Brito
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Brazil
| | - Taís Nóbrega de Sousa
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Brazil
- *Correspondence: Taís Nóbrega de Sousa
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10
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Oyegoke OO, Maharaj L, Akoniyon OP, Kwoji I, Roux AT, Adewumi TS, Maharaj R, Oyebola BT, Adeleke MA, Okpeku M. Malaria diagnostic methods with the elimination goal in view. Parasitol Res 2022; 121:1867-1885. [PMID: 35460369 PMCID: PMC9033523 DOI: 10.1007/s00436-022-07512-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 04/01/2022] [Indexed: 01/08/2023]
Abstract
Malaria control measures have been in use for years but have not completely curbed the spread of infection. Ultimately, global elimination is the goal. A major playmaker in the various approaches to reaching the goal is the issue of proper diagnosis. Various diagnostic techniques were adopted in different regions and geographical locations over the decades, and these have invariably produced diverse outcomes. In this review, we looked at the various approaches used in malaria diagnostics with a focus on methods favorably used during pre-elimination and elimination phases as well as in endemic regions. Microscopy, rapid diagnostic testing (RDT), loop-mediated isothermal amplification (LAMP), and polymerase chain reaction (PCR) are common methods applied depending on prevailing factors, each with its strengths and limitations. As the drive toward the elimination goal intensifies, the search for ideal, simple, fast, and reliable point-of-care diagnostic tools is needed more than ever before to be used in conjunction with a functional surveillance system supported by the ideal vaccine.
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Affiliation(s)
- Olukunle O Oyegoke
- Discipline of Genetics School of Life Sciences, University of KwaZulu-Natal, Westville, Durban, South Africa
| | - Leah Maharaj
- Discipline of Genetics School of Life Sciences, University of KwaZulu-Natal, Westville, Durban, South Africa
| | - Oluwasegun P Akoniyon
- Discipline of Genetics School of Life Sciences, University of KwaZulu-Natal, Westville, Durban, South Africa
| | - Illiya Kwoji
- Discipline of Genetics School of Life Sciences, University of KwaZulu-Natal, Westville, Durban, South Africa
| | - Alexandra T Roux
- Discipline of Genetics School of Life Sciences, University of KwaZulu-Natal, Westville, Durban, South Africa
| | - Taiye S Adewumi
- Discipline of Genetics School of Life Sciences, University of KwaZulu-Natal, Westville, Durban, South Africa
| | - Rajendra Maharaj
- Office of Malaria Research, Medical Research Council, Durban, South Africa
| | | | - Matthew A Adeleke
- Discipline of Genetics School of Life Sciences, University of KwaZulu-Natal, Westville, Durban, South Africa
| | - Moses Okpeku
- Discipline of Genetics School of Life Sciences, University of KwaZulu-Natal, Westville, Durban, South Africa.
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11
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Aschar M, Sanchez MCA, Costa-Nascimento MDJ, Farinas MDLRN, Hristov AD, Lima GFMC, Inoue J, Levi JE, Di Santi SM. Ultrasensitive molecular tests for Plasmodium detection: applicability in control and elimination programs and reference laboratories. Rev Panam Salud Publica 2022; 46:e11. [PMID: 35355692 PMCID: PMC8959250 DOI: 10.26633/rpsp.2022.11] [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: 08/23/2021] [Accepted: 12/07/2021] [Indexed: 11/24/2022] Open
Abstract
Objective. To evaluate molecular tools to detect low-level parasitemia and the five species of Plasmodium that infect humans for use in control and elimination programs, and in reference laboratories. Methods. We evaluated 145 blood samples from patients who tested positive by nested polymerase chain reaction (nPCR), from asymptomatic individuals and from the WHO Global Malaria Programme/United Kingdom National External Quality Assessment Service. Samples were assayed using the genus-specific RealStar® Malaria PCR Kit 1.0 (alt-Gen; altona Diagnostics) and the RealStar® Malaria Screen & Type PCR Kit (alt-S&T; altona Diagnostics). The results from the molecular tests were compared with those from quantitative PCR (qPCR), nPCR and thick blood smear. Results. The levels of parasitemia ranged from 1 to 518 000 parasites/µL, depending on the species. Compared with nPCR, alt-S&T had a sensitivity of 100%, except for identifying P. falciparum, for which the sensitivity was 93.94%. All samples positive by alt-Gen were also positive by nPCR. When comparing alt-Gen to qPCR, the sensitivity was 100% for P. vivax, P. malariae and P. falciparum. For all Plasmodium species, the correlation between cycle threshold values of alt-S&T and alt-Gen compared with qPCR was significant (P < 0.0001, Spearman’s test), with r = 0.8621 for alt-S&T and r = 0.9371 for alt-Gen. When all Plasmodium species were considered, there was a negative correlation between the level of parasitemia and real-time PCR cycle threshold values (P < 0.0001). In this study, only 2 of 28 samples from asymptomatic individuals were positive by thick blood smear; however, all 28 of these samples were positive by alt-S&T. Conclusions. The alt-Gen and alt-S&T assays are suitable for detecting submicroscopic infections for distinct epidemiological purposes, such as for use in surveys and reference laboratories, and screening in blood banks, which will contribute to global efforts to eliminate malaria.
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Affiliation(s)
- Mariana Aschar
- Faculdade de Medicina Universidade de São Paulo São Paulo Brazil Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Maria Carmen A Sanchez
- Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo São Paulo Brazil Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Maria de Jesus Costa-Nascimento
- Secretaria de Estado da Saúde de São Paulo/Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo São Paulo Brazil Secretaria de Estado da Saúde de São Paulo/Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Maria de Lourdes R N Farinas
- Faculdade de Medicina Universidade de São Paulo São Paulo Brazil Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Angélica D Hristov
- Faculdade de Medicina Universidade de São Paulo São Paulo Brazil Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Giselle F M C Lima
- Faculdade de Medicina Universidade de São Paulo São Paulo Brazil Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Juliana Inoue
- Faculdade de Medicina Universidade de São Paulo São Paulo Brazil Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - José E Levi
- Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo São Paulo Brazil Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Silvia M Di Santi
- Secretaria de Estado da Saúde de São Paulo/Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo São Paulo Brazil Secretaria de Estado da Saúde de São Paulo/Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
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12
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Tenfold difference in DNA recovery rate: systematic comparison of whole blood vs. dried blood spot sample collection for malaria molecular surveillance. Malar J 2022; 21:88. [PMID: 35292038 PMCID: PMC8922754 DOI: 10.1186/s12936-022-04122-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 03/07/2022] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Molecular and genomic surveillance is becoming increasingly used to track malaria control and elimination efforts. Blood samples can be collected as whole blood and stored at - 20 °C until DNA extraction, or as dried blood spots (DBS), circumventing the need for a cold chain. Despite the wide use of either method, systematic comparisons of how the method of blood sample preservation affects the limit of detection (LOD) of molecular diagnosis and the proportion of DNA recovered for downstream applications are lacking. METHODS Extractions based on spin columns, magnetic beads, Tween-Chelex, and direct PCR without prior extraction were compared for whole blood and dried blood spots (DBS) using dilution series of Plasmodium falciparum culture samples. Extracted DNA was quantified by qPCR and droplet digital PCR (ddPCR). RESULTS DNA recovery was 5- to 10-fold higher for whole blood compared to DBS, resulting in a 2- to 3-fold lower LOD for both extraction methods compared to DBS. For whole blood, a magnetic bead-based method resulted in a DNA recovery rate of 88-98% when extracting from whole blood compared to 17-33% for a spin-column based method. For extractions from DBS, the magnetic bead-based method resulted in 8-20% DNA recovery, while the spin-column based method resulted in only 2% DNA recovery. The Tween-Chelex method was superior to other methods with 15-21% DNA recovery, and even more sensitive than extractions from whole blood samples. The direct PCR method was found to have the lowest LOD overall for both, whole blood and DBS. CONCLUSIONS Pronounced differences in LOD and DNA yield need to be considered when comparing prevalence estimates based on molecular methods and when selecting sampling protocols for other molecular surveillance applications.
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Hanifian H, Nateghpour M, Motevalli Haghi A, Teimouri A, Razavi S, Fariver L. Development and optimizing a simple and cost-effective medium for in vitro culture of Plasmodium berghei-ANKA strain with conserving its infectivity in BALB/c mice. BMC Res Notes 2022; 15:56. [PMID: 35168649 PMCID: PMC8845400 DOI: 10.1186/s13104-022-05946-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 02/02/2022] [Indexed: 11/13/2022] Open
Abstract
Objectives The current culture system for P. berghei still requires modifications in consistency and long-term maintenance of parasites considering their pathogenicity in culture media. Therefore, this study designed to further improvement of culture conditions and designing a cost-effective culture medium with minimum changes in pathogenicity for in vitro culture of P. berghei. Results Results indicated that the rate of parasitaemia in our modified method remained statistically stable between days one to seven (P = 0.07). The current modified cultivation method was more efficient in maintaining of parasites for further days. Furthermore, in current method the stability of parasitaemia rate during day1 to day7 was in better rate compared to that in Ronan Jambou et al. and the differences between two methods were statistically significant (P = 0.001). The virulence of cultivated parasites in our modified method remained similar to frozen stock parasites as positive control group. No significant differences were seen in survival time between two groups of mice those were infected with either cultivated parasites or stock freeze parasites (P = 0.39) with the mean survival time of 20.83 ± 3.84 and 19.66 ± 1.21 days, respectively. Herein, we achieved a simple, cost-effective and applicable technique for culture of P. berghei. Supplementary Information The online version contains supplementary material available at 10.1186/s13104-022-05946-z.
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Evaluating performance of multiplex real time PCR for the diagnosis of malaria at elimination targeted low transmission settings of Ethiopia. Malar J 2022; 21:9. [PMID: 34986840 PMCID: PMC8734331 DOI: 10.1186/s12936-021-04029-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 12/17/2021] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Malaria incidence has declined in Ethiopia in the past 10 years. Current malaria diagnostic tests, including light microscopy and rapid antigen-detecting diagnostic tests (RDTs) cannot reliably detect low-density infections. Studies have shown that nucleic acid amplification tests are highly sensitive and specific in detecting malaria infection. This study took place with the aim of evaluating the performance of multiplex real time PCR for the diagnosis of malaria using patient samples collected from health facilities located at malaria elimination targeted low transmission settings in Ethiopia. METHODS A health facility-based, cross-sectional survey was conducted in selected malaria sentinel sites. Malaria-suspected febrile outpatients referred to laboratory for malaria testing between December 2019 and March 2020 was enrolled into this study. Sociodemographic information and capillary blood samples were collected from the study participants and tested at spot with RDTs. Additionally, five circles of dry blood spot (DBS) samples on Whatman filter paper and thick and thin smear were prepared for molecular testing and microscopic examination, respectively. Multiplex real time PCR assay was performed at Ethiopian Public Health Institute (EPHI) malaria laboratory. The performance of multiplex real time PCR assay, microscopy and RDT for the diagnosis of malaria was compared and evaluated against each other. RESULTS Out of 271 blood samples, multiplex real time PCR identified 69 malaria cases as Plasmodium falciparum infection, 16 as Plasmodium vivax and 3 as mixed infections. Of the total samples, light microscopy detected 33 as P. falciparum, 18 as P. vivax, and RDT detected 43 as P. falciparum, 17 as P. vivax, and one mixed infection. Using light microscopy as reference test, the sensitivity and specificity of multiplex real time PCR were 100% (95% CI (93-100)) and 83.2% (95% CI (77.6-87.9)), respectively. Using multiplex real time PCR as a reference, light microscopy and RDT had sensitivity of 58% (95% CI 46.9-68.4) and 67% (95% CI 56.2-76.7); and 100% (95% CI 98-100) and 98.9% (95% CI 96-99.9), respectively. Substantial level of agreement was reported between microscopy and multiplex real time PCR results with kappa value of 0.65. CONCLUSIONS Multiplex real-time PCR had an advanced performance in parasite detection and species identification on febrile patients' samples than did microscopy and RDT in low malaria transmission settings. It is highly sensitive malaria diagnostic method that can be used in malaria elimination programme, particularly for community based epidemiological samples. Although microscopy and RDT had reduced performance when compared to multiplex real time PCR, still had an acceptable performance in diagnosis of malaria cases on patient samples at clinical facilities.
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15
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Assessing the Performance of CareStart™ Malaria Rapid Diagnostic Tests in Northwest Ethiopia: A Cross-Sectional Study. J Parasitol Res 2021; 2021:7919984. [PMID: 34725569 PMCID: PMC8556986 DOI: 10.1155/2021/7919984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 10/05/2021] [Indexed: 11/18/2022] Open
Abstract
Background While rapid diagnostic tests are an alternative diagnostic tests for microscopy in the diagnosis of malaria in rural settings, their performance has been inconsistent. Performance of rapid diagnostic tests might be affected by manufacturing process, transportation and storage, parasitemia level, and skill of personnel who perform the tests. Therefore, periodic evaluation of the local field performance of rapid diagnostic tests is mandatory in order to make early corrections in case of decreased performance. Methods A facility-based cross-sectional study was conducted from January to May 2020 among 257 malaria-suspected patients attending selected health centers in Bahir Dar Zuria district. Capillary blood was collected from each participant and tested for Plasmodium infection by CareStart™ rapid diagnostic test kit and thin and thick blood film microscopy. Data were analyzed using statistical software for social sciences version 20 and MedCalc software version 19.3. Sensitivity, specificity, positive and negative predictive values, and kappa value were calculated to evaluate the performance of rapid diagnostic tests against microscopy. Results Among 257 study participants, 47 (18.3%) were tested positive for Plasmodium infection by at least one of the diagnostic methods. Rapid diagnostic tests revealed 3 false positive and 3 false negative results. The sensitivity and specificity of CareStart Malaria Pf/Pv Combo test were 93.2% and 98.6%, respectively (kappa = 0.918). Conclusion CareStart™ rapid diagnostic test has comparable performance with microscopy for malaria diagnosis. We recommend continued use of CareStart Malaria Pf/Pv Combo test at health posts in Ethiopia where microscopy is not available.
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Calderaro A, Montecchini S, Buttrini M, Piccolo G, Rossi S, Arcangeletti MC, Farina B, De Conto F, Chezzi C. Malaria Diagnosis in Non-Endemic Settings: The European Experience in the Last 22 Years. Microorganisms 2021; 9:microorganisms9112265. [PMID: 34835391 PMCID: PMC8620059 DOI: 10.3390/microorganisms9112265] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 11/16/2022] Open
Abstract
Accurate, prompt, and reliable tools for the diagnosis of malaria are crucial for tracking the successes or drawbacks of control and elimination efforts, and for future programs aimed at global malaria eradication. Although microscopy remains the gold standard method, the number of imported malaria cases and the risk of reappearance of autochthonous cases stimulated several laboratories located in European countries to evaluate methods and algorithms suited to non-endemic settings, where skilled microscopists are not always available. In this review, an overview of the field evaluation and a comparison of the methods used for the diagnosis of malaria by European laboratories is reported, showing that the development of numerous innovations is continuous. In particular, the combination of rapid diagnostic tests and molecular assays with microscopy represents a reliable system for the early diagnosis of malaria in non-endemic settings.
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Affiliation(s)
- Adriana Calderaro
- Department of Medicine and Surgery, University of Parma, Viale A. Gramsci 14, 43126 Parma, Italy; (S.M.); (M.B.); (G.P.); (M.C.A.); (B.F.); (F.D.C.); (C.C.)
- Correspondence: ; Tel.: +39-0521-033499; Fax: +39-0521-993620
| | - Sara Montecchini
- Department of Medicine and Surgery, University of Parma, Viale A. Gramsci 14, 43126 Parma, Italy; (S.M.); (M.B.); (G.P.); (M.C.A.); (B.F.); (F.D.C.); (C.C.)
| | - Mirko Buttrini
- Department of Medicine and Surgery, University of Parma, Viale A. Gramsci 14, 43126 Parma, Italy; (S.M.); (M.B.); (G.P.); (M.C.A.); (B.F.); (F.D.C.); (C.C.)
| | - Giovanna Piccolo
- Department of Medicine and Surgery, University of Parma, Viale A. Gramsci 14, 43126 Parma, Italy; (S.M.); (M.B.); (G.P.); (M.C.A.); (B.F.); (F.D.C.); (C.C.)
| | - Sabina Rossi
- Unit of Clinical Microbiology, University Hospital of Parma, Viale A. Gramsci 14, 43126 Parma, Italy;
| | - Maria Cristina Arcangeletti
- Department of Medicine and Surgery, University of Parma, Viale A. Gramsci 14, 43126 Parma, Italy; (S.M.); (M.B.); (G.P.); (M.C.A.); (B.F.); (F.D.C.); (C.C.)
| | - Benedetta Farina
- Department of Medicine and Surgery, University of Parma, Viale A. Gramsci 14, 43126 Parma, Italy; (S.M.); (M.B.); (G.P.); (M.C.A.); (B.F.); (F.D.C.); (C.C.)
| | - Flora De Conto
- Department of Medicine and Surgery, University of Parma, Viale A. Gramsci 14, 43126 Parma, Italy; (S.M.); (M.B.); (G.P.); (M.C.A.); (B.F.); (F.D.C.); (C.C.)
| | - Carlo Chezzi
- Department of Medicine and Surgery, University of Parma, Viale A. Gramsci 14, 43126 Parma, Italy; (S.M.); (M.B.); (G.P.); (M.C.A.); (B.F.); (F.D.C.); (C.C.)
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Gimenez AM, Marques RF, Regiart M, Bargieri DY. Diagnostic Methods for Non-Falciparum Malaria. Front Cell Infect Microbiol 2021; 11:681063. [PMID: 34222049 PMCID: PMC8248680 DOI: 10.3389/fcimb.2021.681063] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/31/2021] [Indexed: 11/13/2022] Open
Abstract
Malaria is a serious public health problem that affects mostly the poorest countries in the world, killing more than 400,000 people per year, mainly children under 5 years old. Among the control and prevention strategies, the differential diagnosis of the Plasmodium-infecting species is an important factor for selecting a treatment and, consequently, for preventing the spread of the disease. One of the main difficulties for the detection of a specific Plasmodium sp is that most of the existing methods for malaria diagnosis focus on detecting P. falciparum. Thus, in many cases, the diagnostic methods neglect the other non-falciparum species and underestimate their prevalence and severity. Traditional methods for diagnosing malaria may present low specificity or sensitivity to non-falciparum spp. Therefore, there is high demand for new alternative methods able to differentiate Plasmodium species in a faster, cheaper and easier manner to execute. This review details the classical procedures and new perspectives of diagnostic methods for malaria non-falciparum differential detection and the possibilities of their application in different circumstances.
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Affiliation(s)
- Alba Marina Gimenez
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rodolfo F. Marques
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Matías Regiart
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Daniel Youssef Bargieri
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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Chaturvedi R, Deora N, Bhandari D, Parvez S, Sinha A, Sharma A. Trends of neglected Plasmodium species infection in humans over the past century in India. One Health 2021; 11:100190. [PMID: 33251321 PMCID: PMC7683271 DOI: 10.1016/j.onehlt.2020.100190] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 10/22/2020] [Accepted: 10/23/2020] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Efforts for malaria elimination in India focus solely on the more prevalent human malaria parasites of Plasmodium falciparum (Pf) and Plasmodium vivax (Pv). The three non-Pf/Pv species - Plasmodium malariae (Pm), Plasmodium ovale (Po) and Plasmodium knowlesi (Pk) are seldom studied though they are often present as mixed infections with Pf/Pv and thus may be misdiagnosed. This study provides a comprehensive landscape of Pm, Po, and Pk infections from 1930 to 2020. METHODOLOGY We systematically searched for published literature on Pm, Po, and Pk in India from PubMed database and collated data from 35 studies. The data, starting from 1930, were mapped decade-wise across India. The prevalence of the three neglected Plasmodium species and their proportional contribution to reported Plasmodium mixed-infection were also calculated and analysed. PRINCIPAL FINDINGS Amongst the three non-Pf/Pv species, Pm infections have been reported in greater numbers across India and were mostly mono-infections till 1980. From 1983 onwards, reports of Pm mixed infections with Pf/Pv started to emerge. In contrast, reports on occurrence of Po are still rare barring few mixed infection studies. Further, Pk mono- and mixed cases were first reported in 2004 in India and Pk now has been found reported from four Indian states. CONCLUSION This is the first account of country-wide assimilation of reported malaria parasite species data that covers Pm, Po, and Pk infection profiles from 1930 to 2020. This study illustrates the need to survey all 5 human malaria parasite species in India and to target them collectively during the malaria elimination phase.
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Key Words
- ACT, Artemisinin-based combination therapy
- AL, Artemether-Lumefantrine
- AS, Artesunate
- CDC, Centres for Disease Control and Prevention
- DBS, Dried Blood Spots
- G6PD, Glucose-6-Phosphate Dehydrogenase.
- IV, intravenous
- LAMP, Loop-mediated isothermal amplification.
- Neglected Plasmodium species
- P. knowlesi
- P. malariae
- P. ovale
- PCR, Polymerase Chain Reaction
- POC, Point of Care,
- RDT, Rapid Diagnostic Tests
- SP, Sulfadoxine-Pyrimethamine
- malaria
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Affiliation(s)
- Rini Chaturvedi
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
- Department of Toxicology, Jamia Hamdard, New Delhi, India
| | - Nimita Deora
- ICMR-National Institute of Malaria Research, New Delhi, India
| | - Deepam Bhandari
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Suhel Parvez
- Department of Toxicology, Jamia Hamdard, New Delhi, India
| | - Abhinav Sinha
- ICMR-National Institute of Malaria Research, New Delhi, India
| | - Amit Sharma
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
- ICMR-National Institute of Malaria Research, New Delhi, India
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Laboratory Detection of Malaria Antigens: a Strong Tool for Malaria Research, Diagnosis, and Epidemiology. Clin Microbiol Rev 2021; 34:e0025020. [PMID: 34043447 DOI: 10.1128/cmr.00250-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The identification and characterization of proteins produced during human infection with Plasmodium spp. have guided the malaria community in research, diagnosis, epidemiology, and other efforts. Recently developed methods for the detection of these proteins (antigens) in the laboratory have provided new types of data that can inform the evaluation of malaria diagnostics, epidemiological investigations, and overall malaria control strategies. Here, the focus is primarily on antigens that are currently known to be detectable in human specimens and on their impact on the understanding of malaria in human populations. We highlight historical and contemporary laboratory assays for malaria antigen detection, the concept of an antigen profile for a biospecimen, and ways in which binary results for a panel of antigens could be interpreted and utilized for different analyses. Particular emphasis is given to the direct comparison of field-level malaria diagnostics and laboratory antigen detection for the development of an external evaluation scheme. The current limitations of laboratory antigen detection are considered, and the future of this developing field is discussed.
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McGinnis E, Chan G, Hudoba M, Markin T, Yakimec J, Roland K. Malaria Screening Using Front-Line Loop-Mediated Isothermal Amplification. Am J Clin Pathol 2021; 155:690-697. [PMID: 33283225 DOI: 10.1093/ajcp/aqaa173] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES We implemented front-line loop-mediated isothermal amplification (LAMP)-based malaria screening in our nonendemic multicenter health region to reduce reliance on microscopy without sacrificing diagnostic efficiency. We aimed to evaluate changes in test volumes, positivity rates, turnaround times, and approximate labor time savings resulting from implementation of LAMP-based malaria testing to assess the efficacy of the novel testing algorithm in our regional hub-and-spoke testing model. METHODS We reviewed data generated from institutional malaria testing between 2016 and 2019, having implemented LAMP in October 2018 as a front-line screening test for all malaria investigations from our hub facility and investigations from satellite facilities with negative rapid diagnostic tests (RDTs) and microscopy. RESULTS Blood film microscopy and RDT workloads decreased substantially in the year following LAMP implementation (by 90% and 46%, respectively,) despite similar numbers of patients tested and positivity rates for malaria compared with historical data. LAMP turnaround times (TATs) were comparable to historical TATs for RDTs, and TATs for RDTs and thick films did not increase with the change in workflow. CONCLUSIONS LAMP was successfully implemented in our multicenter health region malaria diagnostic algorithm, significantly reducing reliance on microscopic evaluations and RDT and providing substantial labor time savings without compromising TATs.
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Affiliation(s)
- Eric McGinnis
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Geoffrey Chan
- Division of Hematopathology, Department of Pathology and Laboratory Medicine, Vancouver General Hospital, Vancouver, Canada
| | - Monika Hudoba
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
- Division of Hematopathology, Department of Pathology and Laboratory Medicine, Vancouver General Hospital, Vancouver, Canada
| | - Todd Markin
- Division of Hematopathology, Department of Pathology and Laboratory Medicine, Vancouver General Hospital, Vancouver, Canada
| | - Jim Yakimec
- Division of Hematopathology, Department of Pathology and Laboratory Medicine, Vancouver General Hospital, Vancouver, Canada
| | - Kristine Roland
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
- Division of Hematopathology, Department of Pathology and Laboratory Medicine, Vancouver General Hospital, Vancouver, Canada
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Zuluaga-Idárraga L, Rios A, Sierra-Cifuentes V, Garzón E, Tobón-Castaño A, Takehara I, Toya Y, Izuka M, Uchihashi K, Lopera-Mesa TM. Performance of the hematology analyzer XN-31 prototype in the detection of Plasmodium infections in an endemic region of Colombia. Sci Rep 2021; 11:5268. [PMID: 33664389 PMCID: PMC7933134 DOI: 10.1038/s41598-021-84594-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 02/16/2021] [Indexed: 11/10/2022] Open
Abstract
Early and accurate diagnosis is critical in reducing the morbidity and mortality associated with malaria. Microscopy (MI) is the current diagnostic gold standard in the field; however, it requires expert personnel, is time-consuming, and has limited sensitivity. Although rapid diagnostic tests for antigen detection (RDTs) are an alternative to diagnosis, they also have limited sensitivity and produce false positive results in detecting recent past infection. The automated hematology analyzer XN-31 prototype (XN-31p) (Sysmex Corporation, Kobe, Japan) is able to identify plasmodium-infected erythrocytes, count parasitemia and perform complete blood-cell counts within one minute. The performance of the XN-31p in diagnosing malaria was evaluated and compared with real-time polymerase chain reaction (qPCR), MI and RDT in an endemic area of Colombia where Plasmodium falciparum and Plasmodium vivax are present. Acute febrile patients were enrolled from July 2018 to April 2019 in Quibdó, Colombia. Malaria diagnoses were obtained from MI and RDT in the field and later confirmed by qPCR. Venous blood samples in EDTA were processed with an XN-31p in the field. Sensitivity, specificity, positive/negative predictive values, and the likelihood ratios of positive and negative tests were calculated with respect to the results from qPCR, MI and RDT. The intraclass correlation coefficient (ICC) and Bland–Altman plot were used to evaluate the concordance in the parasitemia with respect to MI. A total of 1,754 subjects were enrolled. The mean age was 27.0 years (IQR 14–44); 89.6% were Afro-Colombians, 94.3% lived in urban areas and 0.91% were pregnant. With respect to qPCR, the XN-31p showed a sensitivity of 90% (95% CI 87.24–92.34) and a specificity of 99.83% (95% CI 99.38–99.98) in detecting Plasmodium spp.; both parameters were equivalent to those for MI and RDT. Using MI as the reference, the XN-31p showed a sensitivity of 98.09% (95% CI 96.51–99.08), a specificity of 99.83% (95% CI 99.4–99.98), an ICC of 0.85 (95% CI 0.83–0.87) and an average difference of − 3096 parasites/µL when compared with thick-smear MI and an ICC of 0.98 (95% CI 0.97–0.98) and an average difference of − 0.0013% when compared with thin-smear MI. The XN-31p offers a rapid and accurate alternative method for diagnosing malaria in clinical laboratories in areas where P. falciparum and P. vivax cocirculate.
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Affiliation(s)
- Lina Zuluaga-Idárraga
- Grupo Malaria, Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia.
| | - Alexandra Rios
- Grupo Malaria, Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia
| | - Verónica Sierra-Cifuentes
- Grupo Malaria, Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia
| | - Edwar Garzón
- Grupo Malaria, Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia
| | - Alberto Tobón-Castaño
- Grupo Malaria, Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia
| | - Ikki Takehara
- Sysmex Corporation, 1-5-1 Wakinohama-Kaigandori, Chuo-ku, Kobe, Hyogo, 651-0073, Japan
| | - Yuji Toya
- Sysmex Corporation, 1-5-1 Wakinohama-Kaigandori, Chuo-ku, Kobe, Hyogo, 651-0073, Japan
| | - Munehisa Izuka
- Sysmex Corporation, 1-5-1 Wakinohama-Kaigandori, Chuo-ku, Kobe, Hyogo, 651-0073, Japan
| | - Kinya Uchihashi
- Sysmex Corporation, 1-5-1 Wakinohama-Kaigandori, Chuo-ku, Kobe, Hyogo, 651-0073, Japan
| | - Tatiana M Lopera-Mesa
- Grupo Malaria, Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia
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Mahittikorn A, Masangkay FR, Kotepui KU, De Jesus Milanez G, Kotepui M. Comparative performance of PCR using DNA extracted from dried blood spots and whole blood samples for malaria diagnosis: a meta-analysis. Sci Rep 2021; 11:4845. [PMID: 33649410 PMCID: PMC7921648 DOI: 10.1038/s41598-021-83977-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 02/10/2021] [Indexed: 11/24/2022] Open
Abstract
Polymerase chain reaction (PCR) using deoxyribonucleic acid (DNA) extracted from dried blood spots (DBS) provides a fast, inexpensive, and convenient method for large-scale epidemiological studies. This study compared the performance of PCR between DNA extracted from DBS and DNA obtained from whole blood for detecting malarial parasites. Primary studies assessing the diagnostic performance of PCR using DNA extracted from DBS and whole blood for detecting malarial parasites were obtained from the ISI Web of Science, Scopus, and PubMed databases. Odds ratios (ORs) and 95% confidence intervals (CIs) were plotted in forest plots using Review Manager version 5.3. Statistical analysis was performed via random-effects meta-analysis. Data heterogeneity was assessed using the I2 statistic. Of the 904 studies retrieved from the databases, seven were included in this study. The pooled meta-analysis demonstrated no significant difference in the comparative performance of PCR for detecting malaria parasites between DNA extracted from DBS and that extracted from whole blood (OR 0.85; 95% CI 0.62–1.16; I2 = 78%). However, subgroup analysis demonstrated that PCR using DNA extracted from DBS was less accurate in detecting Plasmodium vivax than that using DNA extracted from whole blood (OR = 0.85; 95% CI 0.77–0.94). In conclusion, a significant difference in detecting P. vivax was observed between PCR using DNA extracted from DBS and that using DNA extracted from whole blood. Therefore, P. vivax in endemic areas should be identified and detected with care with PCR using DNA obtained from DBS which potentially leads to a negative result. Further studies are required to investigate the performance of PCR using DBS for detecting P. vivax and other malarial parasites to provide data in research and routine surveillance of malaria, especially with renewed efforts towards the eradication of the disease.
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Affiliation(s)
- Aongart Mahittikorn
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Frederick Ramirez Masangkay
- Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University-Manila, Manila, Philippines
| | - Kwuntida Uthaisar Kotepui
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand
| | - Giovanni De Jesus Milanez
- Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University-Manila, Manila, Philippines
| | - Manas Kotepui
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand.
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Kolluri N, Kamath S, Lally P, Zanna M, Galagan J, Gitaka J, Kamita M, Cabodi M, Lolabattu SR, Klapperich CM. Development and Clinical Validation of Iso-IMRS: A Novel Diagnostic Assay for P. falciparum Malaria. Anal Chem 2021; 93:2097-2105. [PMID: 33464825 PMCID: PMC7859932 DOI: 10.1021/acs.analchem.0c03847] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
In many countries
targeting malaria elimination, persistent malaria
infections can have parasite loads significantly below the lower limit
of detection (LLOD) of standard diagnostic techniques, making them
difficult to identify and treat. The most sensitive diagnostic methods
involve amplification and detection of Plasmodium DNA by polymerase chain reaction (PCR), which requires expensive
thermal cycling equipment and is difficult to deploy in resource-limited
settings. Isothermal DNA amplification assays have been developed,
but they require
complex primer design, resulting in high nonspecific amplification,
and show a decrease in sensitivity than PCR methods. Here, we have
used a computational approach to design a novel isothermal amplification
assay with a simple primer design to amplify P. falciparum DNA with analytical sensitivity comparable to PCR. We have identified
short DNA sequences repeated throughout the parasite genome to be
used as primers for DNA amplification and demonstrated that these
primers can be used, without modification, to isothermally amplify P. falciparum parasite DNA via strand displacement
amplification. Our novel assay shows a LLOD of ∼1 parasite/μL
within a 30 min amplification time. The assay was demonstrated with
clinical samples using patient blood and saliva. We further characterized
the assay using direct amplicon next-generation sequencing and modified
the assay to work with a visual readout. The technique developed here
achieves similar analytical sensitivity to current gold standard PCR
assays requiring a fraction of time and resources for PCR. This highly
sensitive isothermal assay can be more easily adapted to field settings,
making it a potentially useful tool for malaria elimination.
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Affiliation(s)
- Nikunja Kolluri
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Room 702, Boston, Massachusetts 02215, United States
| | - Shwetha Kamath
- Division of Research and Development, Jigsaw Bio Solutions Private Limited, No. 87, 4th Floor, Mundhra Chambers, 22nd Main, Banashankari 2nd Stage, Bangalore 560070, Karnataka, India
| | - Patrick Lally
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Room 702, Boston, Massachusetts 02215, United States
| | - Mina Zanna
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Room 702, Boston, Massachusetts 02215, United States
| | - James Galagan
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Room 702, Boston, Massachusetts 02215, United States
| | - Jesse Gitaka
- Directorate of Research and Innovation, Mount Kenya University, General Kago Road, P.O. Box 342, Thika 01000, Kenya
| | - Moses Kamita
- Directorate of Research and Innovation, Mount Kenya University, General Kago Road, P.O. Box 342, Thika 01000, Kenya
| | - Mario Cabodi
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Room 702, Boston, Massachusetts 02215, United States
| | - Srinivasa Raju Lolabattu
- Division of Research and Development, Jigsaw Bio Solutions Private Limited, No. 87, 4th Floor, Mundhra Chambers, 22nd Main, Banashankari 2nd Stage, Bangalore 560070, Karnataka, India
| | - Catherine M Klapperich
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Room 702, Boston, Massachusetts 02215, United States
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Gachugia J, Chebore W, Otieno K, Ngugi CW, Godana A, Kariuki S. Evaluation of the colorimetric malachite green loop-mediated isothermal amplification (MG-LAMP) assay for the detection of malaria species at two different health facilities in a malaria endemic area of western Kenya. Malar J 2020; 19:329. [PMID: 32907582 PMCID: PMC7487890 DOI: 10.1186/s12936-020-03397-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 08/30/2020] [Indexed: 01/03/2023] Open
Abstract
Background Prompt diagnosis and effective malaria treatment is a key strategy in malaria control. However, the recommended diagnostic methods, microscopy and rapid diagnostic tests (RDTs), are not supported by robust quality assurance systems in endemic areas. This study compared the performance of routine RDTs and smear microscopy with a simple molecular-based colorimetric loop-mediated isothermal amplification (LAMP) at two different levels of the health care system in a malaria-endemic area of western Kenya. Methods Patients presenting with clinical symptoms of malaria at Rota Dispensary (level 2) and Siaya County Referral Hospital (level 4) were enrolled into the study after obtaining written informed consent. Capillary blood was collected to test for malaria by RDT and microscopy at the dispensary and county hospital, and for preparation of blood smears and dried blood spots (DBS) for expert microscopy and real-time polymerase chain reaction (RT-PCR). Results of the routine diagnostic tests were compared with those of malachite green loop-mediated isothermal amplification (MG-LAMP) performed at the two facilities. Results A total of 264 participants were enrolled into the study. At the dispensary level, the positivity rate by RDT, expert microscopy, MG-LAMP and RT-PCR was 37%, 30%, 44% and 42%, respectively, and 42%, 43%, 57% and 43% at the county hospital. Using RT-PCR as the reference test, the sensitivity of RDT and MG-LAMP was 78.1% (CI 67.5–86.4) and 82.9% (CI 73.0–90.3) at Rota dispensary. At Siaya hospital the sensitivity of routine microscopy and MG-LAMP was 83.3% (CI 65.3–94.4) and 93.3% (CI 77.9–99.2), respectively. Compared to MG-LAMP, there were 14 false positives and 29 false negatives by RDT at Rota dispensary and 3 false positives and 13 false negatives by routine microscopy at Siaya Hospital. Conclusion MG-LAMP is more sensitive than RDTs and microscopy in the detection of malaria parasites at public health facilities and might be a useful quality control tool in resource-limited settings.
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Affiliation(s)
- James Gachugia
- Department of Medical Microbiology, College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, P. O. Box 62000-00200, Nairobi, Kenya
| | - Winnie Chebore
- Kenya Medical Research Institute, Centre for Global Health Research, P. O. Box 1578-40100, Kisumu, Kenya
| | - Kephas Otieno
- Kenya Medical Research Institute, Centre for Global Health Research, P. O. Box 1578-40100, Kisumu, Kenya
| | - Caroline Wangari Ngugi
- Department of Medical Microbiology, College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, P. O. Box 62000-00200, Nairobi, Kenya
| | - Adano Godana
- National Malaria Control Programme, Ministry of Health, Kenyatta National Hospital, P. O. Box, Nairobi, 19982-00202, Kenya
| | - Simon Kariuki
- Kenya Medical Research Institute, Centre for Global Health Research, P. O. Box 1578-40100, Kisumu, Kenya.
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Picot S, Cucherat M, Bienvenu AL. Systematic review and meta-analysis of diagnostic accuracy of loop-mediated isothermal amplification (LAMP) methods compared with microscopy, polymerase chain reaction and rapid diagnostic tests for malaria diagnosis. Int J Infect Dis 2020; 98:408-419. [PMID: 32659450 DOI: 10.1016/j.ijid.2020.07.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 07/01/2020] [Accepted: 07/05/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Diagnosis is a challenging issue for eliminating malaria. Loop-mediated isothermal amplification (LAMP) could be an alternative to conventional methods. This study aimed to evaluate the diagnostic accuracy of LAMP for malaria compared with microscopy, polymerase chain reaction (PCR) and rapid diagnostic tests (RDTs). METHODS AND DESIGN MEDLINE, Web of Science and Scopus were searched from inception to 1 July 2019. Prospective and retrospective, randomised and non-randomised, mono-center and multi-center studies, including symptomatic or asymptomatic patients, that reported one LAMP method and one comparator (microscopy, RDT or PCR) were included. PROSPERO registration number: CRD42017075186. RESULTS Sixty-six studies published between 2006 and 2019 were included, leading to the analysis of 30,641 LAMP tests. The pooled sensitivity of LAMP remained between 96% and 98%, whichever the comparator. The pooled specificity of LAMP was around 95%, but was a little higher if the best PCR studies were considered. The AUC was found to be >0.98, whichever the subgroup of studies was considered. Diagnostic odds ratio (DOR) was found to be around 1000 for all subgroups, except for Plasmodium vivax. CONCLUSION This meta-analysis confirmed that the LAMP method is robust for diagnosing malaria, both in symptomatic and asymptomatic people. Thus, the impact of LAMP for controlling malaria is expected to be important.
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Affiliation(s)
- Stephane Picot
- Malaria Research Unit, SMITh, ICBMS UMR 5246 CNRS-INSA-CPE-Université de Lyon, Campus Lyon-Tech La Doua, 69622 Villeurbanne Cedex, France; Institut de Parasitologie et Mycologie Médicale, Hôpital de La Croix-Rousse, Hospices Civils de Lyon, Lyon, France
| | - Michel Cucherat
- Service de Pharmacotoxicologie, Hospices Civils de Lyon, Laboratoire de Biométrie et Biologie Évolutive, CNRS, UMR5558, Université Lyon 1, Lyon, France
| | - Anne-Lise Bienvenu
- Malaria Research Unit, SMITh, ICBMS UMR 5246 CNRS-INSA-CPE-Université de Lyon, Campus Lyon-Tech La Doua, 69622 Villeurbanne Cedex, France; Service Pharmacie, Groupement Hospitalier Nord, Hospices Civils de Lyon, France; Service d'Hématologie, Groupement Hospitalier Nord, Hospices Civils de Lyon, France.
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Soniran OT, Abuaku B, Ahorlu CS. Evaluating interventions to improve test, treat, and track (T3) malaria strategy among over-the-counter medicine sellers (OTCMS) in some rural communities of Fanteakwa North district, Ghana: study protocol for a cluster randomized controlled trial. Trials 2020; 21:623. [PMID: 32641094 PMCID: PMC7346649 DOI: 10.1186/s13063-020-04509-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 06/15/2020] [Indexed: 11/17/2022] Open
Abstract
Background The World Health Organization initiated test, treat, and track (T3) malaria strategy to support malaria-endemic countries in their efforts to achieve universal coverage with diagnostic testing, antimalarial treatment, and strengthening surveillance systems. Unfortunately, T3 is not adopted by over-the-counter medicine sellers (OTCMS) where many patients with malaria-like symptoms first seek treatment. Sub-Saharan African countries are considering introducing and scaling up RDTs in these outlets to reduce malaria burden. In this context, this study is aimed at improving implementation of the T3 among OTCMS using a number of intervention tools that could be scaled-up easily at the national level. Methods/design The interventions will be evaluated using a two-arm, cluster randomized trial across 8 rural communities (4 clusters per arm), in two adjacent districts (Fanteakwa North and Fanteakwa South districts) of Ghana. A total of 8 OTCMS in the intervention arm and 5 OTCMS in the control arm in the selected communities will participate in the study. In the intervention arm only, subsidized malaria rapid diagnostic test (mRDT) kits will be introduced after the OTCMS have been trained on how to use the kit appropriately. Supervision, technical assistance, feedbacks, and collection of data will be provided on a regular basis at the participating medicine stores. The primary outcome is the proportion of children under 10 years with fever or suspected to have malaria visiting OTCMS and tested (using mRDT) before treatment. Secondary outcomes will include adherence to national malaria treatment guidelines and recommended mRDT retail price. Outcomes will be measured using mainly a household survey supplemented by mystery client survey and a surveillance register on malaria tests conducted by the OTCMS during patient consultations. Data collected will be double entered and verified using Microsoft Access 2010 (Microsoft Inc., Redmond, Washington) and analyzed using STATA version 11.0. Discussion The trial will provide evidence on the combined effectiveness of provider and community interventions in improving adherence to the T3 initiative among OTCMS in rural Ghana. Ethical clearance NMIMR-IRB CPN 086/18-19 Trial registration ISRCTN registry ISRCTN77836926. Registered on 4 November 2019.
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Affiliation(s)
- Olajoju Temidayo Soniran
- Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana.,Akanu Ibiam Federal Polytechnic, Unwana, Ebonyi State, Nigeria
| | - Benjamin Abuaku
- Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana.
| | - Collins Stephen Ahorlu
- Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
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Di Gregorio E, Ferrauto G, Schwarzer E, Gianolio E, Valente E, Ulliers D, Aime S, Skorokhod O. Relaxometric studies of erythrocyte suspensions infected by Plasmodium falciparum: a tool for staging infection and testing anti-malarial drugs. Magn Reson Med 2020; 84:3366-3378. [PMID: 32602953 DOI: 10.1002/mrm.28387] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 05/26/2020] [Accepted: 05/29/2020] [Indexed: 12/23/2022]
Abstract
PURPOSE Malaria is a global health problem with the most malignant form caused by Plasmodium falciparum (P. falciparum). Parasite maturation in red blood cells (RBCs) is accompanied by changes including the formation of paramagnetic hemozoin (HZ) nanocrystals, and increased metabolism and variation in membrane lipid composition. Herein, MR relaxometry (MRR) was applied to investigate water exchange across RBCs' membrane and HZ formation in parasitized RBCs. METHODS Transverse water protons relaxation rate constants (R2 = 1/T2 ) were measured for assessing HZ formation in P. falciparum-parasitized human RBCs. Moreover, water exchange lifetimes across the RBC membrane (τi ) were assessed by measuring longitudinal relaxation rate constants (R1 = 1/T1 ) at 21.5 MHz in the presence of a gadolinium complex dissolved in the suspension medium. RESULTS τi increased after invasion of parasites (ring stage, mean τi / τ i 0 = 1.234 ± 0.022) and decreased during maturation to late trophozoite (mean τi / τ i 0 = 0.960 ± 0.075) and schizont stages (mean τi / τ i 0 = 1.019 ± 0.065). The HZ accumulation in advanced stages was revealed by T2 -shortening. The curves reporting R2 (1/T2 ) vs. magnetic field showed different slopes for non-parasitized RBCs (npRBCs) and parasitized RBCs (pRBCs), namely 0.003 ± 0.001 for npRBCs, 0.009 ± 0.002, 0.028 ± 0.004 and 0.055 ± 0.002 for pRBCs at ring-, early trophozoite-, and late trophozoite stage, respectively. Antimalarial molecules dihydroartemisinin and chloroquine elicited measurable changes in parasitized RBCs, namely dihydroartemisinin modified τi , whereas the interference of chloroquine with HZ formation was detectable by a significant T2 increase. CONCLUSIONS MRR can be considered a useful tool for reporting on P. falciparum blood stages and for screening potential antimalarial molecules.
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Affiliation(s)
- Enza Di Gregorio
- Molecular Imaging Center, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy
| | - Giuseppe Ferrauto
- Molecular Imaging Center, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy
| | | | - Eliana Gianolio
- Molecular Imaging Center, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy
| | - Elena Valente
- Department of Oncology, University of Torino, Torino, Italy
| | | | - Silvio Aime
- Molecular Imaging Center, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy
| | - Oleksii Skorokhod
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
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Pasquier G, Azoury V, Sasso M, Laroche L, Varlet-Marie E, Houzé S, Lachaud L, Bastien P, Sterkers Y, Leveque MF. Rapid diagnostic tests failing to detect infections by Plasmodium falciparum encoding pfhrp2 and pfhrp3 genes in a non-endemic setting. Malar J 2020; 19:179. [PMID: 32393251 PMCID: PMC7216663 DOI: 10.1186/s12936-020-03251-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 05/01/2020] [Indexed: 11/10/2022] Open
Abstract
Background Rapid diagnostic tests (RDTs) detecting the histidine-rich protein 2 (PfHRP2) have a central position for the management of Plasmodium falciparum infections. Yet, variable detection of certain targeted motifs, low parasitaemia, but also deletion of pfhrp2 gene or its homologue pfhrp3, may result in false-negative RDT leading to misdiagnosis and delayed treatment. This study aimed at investigating the prevalence, and understanding the possible causes, of P. falciparum RDT-negative infections at Montpellier Academic Hospital, France. Methods The prevalence of falsely-negative RDT results reported before and after the introduction of a loop-mediated isothermal amplification (LAMP) assay, as part as the malaria screening strategy in January 2017, was analysed. Negative P. falciparum RDT infections were screened for pfhrp2 or pfhrp3 deletion; and exons 2 were sequenced to show a putative genetic diversity impairing PfHRP2 detection. Results The overall prevalence of P. falciparum negative RDTs from January 2006 to December 2018 was low (3/446). Whereas no cases were reported from 2006 to 2016 (0/373), period during which the malaria diagnostic screen was based on microscopy and RDT, prevalence increased up to 4.1% (3/73) between 2017 and 2018, when molecular detection was implemented for primary screening. Neither pfhrp2/3 deletion nor major variation in the frequency of repetitive epitopes could explain these false-negative RDT results. Conclusion This paper demonstrates the presence of pfhrp2 and pfhrp3 genes in three P. falciparum RDT-negative infections and reviews the possible reasons for non-detection of HRP2/3 antigens in a non-endemic setting. It highlights the emergence of falsely negative rapid diagnostic tests in a non-endemic setting and draws attention on the risk of missing malaria cases with low parasitaemia infections using the RDT plus microscopy-based strategy currently recommended by French authorities. The relevance of a novel diagnostic scheme based upon a LAMP assay is discussed.
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Affiliation(s)
- Grégoire Pasquier
- University of Montpellier, CNRS, IRD, UMR MiVEGEC, Montpellier, France.,Department of Parasitology-Mycology, CHU de Montpellier, Montpellier, France
| | - Vincent Azoury
- Department of Parasitology-Mycology, CHU de Montpellier, Montpellier, France
| | - Milène Sasso
- University of Montpellier, CNRS, IRD, UMR MiVEGEC, Montpellier, France.,Laboratory of Microbiology, CHU de Nîmes, Nîmes, France
| | - Laëtitia Laroche
- Department of Parasitology-Mycology, CHU de Montpellier, Montpellier, France
| | | | - Sandrine Houzé
- Centre National de Référence du Paludisme, APHP, Hôpital Bichat-Claude Bernard, Paris, France
| | - Laurence Lachaud
- University of Montpellier, CNRS, IRD, UMR MiVEGEC, Montpellier, France.,Department of Parasitology-Mycology, CHU de Montpellier, Montpellier, France
| | - Patrick Bastien
- University of Montpellier, CNRS, IRD, UMR MiVEGEC, Montpellier, France.,Department of Parasitology-Mycology, CHU de Montpellier, Montpellier, France
| | - Yvon Sterkers
- University of Montpellier, CNRS, IRD, UMR MiVEGEC, Montpellier, France.,Department of Parasitology-Mycology, CHU de Montpellier, Montpellier, France
| | - Maude F Leveque
- University of Montpellier, CNRS, IRD, UMR MiVEGEC, Montpellier, France. .,Department of Parasitology-Mycology, CHU de Montpellier, Montpellier, France.
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Abstract
Malaria is a vector-borne disease that involves multiple parasite species in a variety of ecological settings. However, the parasite species causing the disease, the prevalence of subclinical infections, the emergence of drug resistance, the scale-up of interventions, and the ecological factors affecting malaria transmission, among others, are aspects that vary across areas where malaria is endemic. Such complexities have propelled the study of parasite genetic diversity patterns in the context of epidemiologic investigations. Importantly, molecular studies indicate that the time and spatial distribution of malaria cases reflect epidemiologic processes that cannot be fully understood without characterizing the evolutionary forces shaping parasite population genetic patterns. Although broad in scope, this review in the Microbiology Spectrum Curated Collection: Advances in Molecular Epidemiology highlights the need for understanding population genetic concepts when interpreting parasite molecular data. First, we discuss malaria complexity in terms of the parasite species involved. Second, we describe how molecular data are changing our understanding of malaria incidence and infectiousness. Third, we compare different approaches to generate parasite genetic information in the context of epidemiologically relevant questions related to malaria control. Finally, we describe a few Plasmodium genomic studies as evidence of how these approaches will provide new insights into the malaria disease dynamics. *This article is part of a curated collection.
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30
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Use of real-time multiplex PCR, malaria rapid diagnostic test and microscopy to investigate the prevalence of Plasmodium species among febrile hospital patients in Sierra Leone. Malar J 2020; 19:84. [PMID: 32085711 PMCID: PMC7035765 DOI: 10.1186/s12936-020-03163-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 02/13/2020] [Indexed: 11/24/2022] Open
Abstract
Background Malaria continues to affect over 200 million individuals every year, especially children in Africa. Rapid and sensitive detection and identification of Plasmodium parasites is crucial for treating patients and monitoring of control efforts. Compared to traditional diagnostic methods such as microscopy and rapid diagnostic tests (RDTs), DNA based methods, such as polymerase chain reaction (PCR) offer significantly higher sensitivity, definitive discrimination of Plasmodium species, and detection of mixed infections. While PCR is not currently optimized for routine diagnostics, its role in epidemiological studies is increasing as the world moves closer toward regional and eventually global malaria elimination. This study demonstrates the field use of a novel, ambient temperature-stabilized, multiplexed PCR assay in a small hospital setting in Sierra Leone. Methods Blood samples from 534 febrile individuals reporting to a hospital in Bo, Sierra Leone, were tested using three methods: a commercial RDT, microscopy, and a Multiplex Malaria Sample Ready (MMSR) PCR designed to detect a universal malaria marker and species-specific markers for Plasmodium falciparum and Plasmodium vivax. A separate PCR assay was used to identify species of Plasmodium in samples in which MMSR detected malaria, but was unable to identify the species. Results MMSR detected the presence of any malaria marker in 50.2% of all tested samples with P. falciparum identified in 48.7% of the samples. Plasmodium vivax was not detected. Testing of MMSR P. falciparum-negative/universal malaria-positive specimens with a panel of species-specific PCRs revealed the presence of Plasmodium malariae (n = 2) and Plasmodium ovale (n = 2). The commercial RDT detected P. falciparum in 24.6% of all samples while microscopy was able to detect malaria in 12.8% of tested specimens. Conclusions Wider application of PCR for detection of malaria parasites may help to fill gaps existing as a result of use of microscopy and RDTs. Due to its high sensitivity and specificity, species coverage, room temperature stability and relative low complexity, the MMSR assay may be useful for detection of malaria and epidemiological studies especially in low-resource settings.
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31
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Burdino E, Calleri G, Ghisetti V. Added value of loop-mediated isothermal amplification technology (LAMP) in real life for the diagnosis of malaria in travellers. J Travel Med 2019; 26:5537692. [PMID: 31411701 DOI: 10.1093/jtm/taz052] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/16/2019] [Accepted: 07/16/2019] [Indexed: 12/12/2022]
Abstract
Malaria diagnosis in non-endemic countries is questioned by lack of experience and low levels of parasite densities. Loop-mediated isothermal amplification (LAMP) is aimed at simplifying these challenges. In a prospective evaluation over a 2-year period, LAMP significantly simplified malaria identification in 478 febrile travellers and can be considered the primary diagnostic test in this setting.
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Affiliation(s)
- Elisa Burdino
- Laboratory of Microbiology and Virology, Amedeo di Savoia Hospital, ASL Città di Torino, Turin, Italy
| | - Guido Calleri
- Unit A of Infectious and Tropical Diseases, Amedeo di Savoia Hospital, ASL Città di Torino, Turin, Italy
| | - Valeria Ghisetti
- Laboratory of Microbiology and Virology, Amedeo di Savoia Hospital, ASL Città di Torino, Turin, Italy
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32
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Watson OJ, Sumner KM, Janko M, Goel V, Winskill P, Slater HC, Ghani A, Meshnick SR, Parr JB. False-negative malaria rapid diagnostic test results and their impact on community-based malaria surveys in sub-Saharan Africa. BMJ Glob Health 2019; 4:e001582. [PMID: 31406591 PMCID: PMC6666813 DOI: 10.1136/bmjgh-2019-001582] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/30/2019] [Accepted: 07/02/2019] [Indexed: 12/24/2022] Open
Abstract
Surveillance and diagnosis of Plasmodium falciparum malaria relies predominantly on rapid diagnostic tests (RDT). However, false-negative (FN) RDT results are known to occur for a variety of reasons, including operator error, poor storage conditions, pfhrp2/3 gene deletions, poor performance of specific RDT brands and lots, and low-parasite density infections. We used RDT and microscopy results from 85 000 children enrolled in Demographic Health Surveys and Malaria Indicator Surveys from 2009 to 2015 across 19 countries to explore the distribution of and risk factors for FN-RDTs in sub-Saharan Africa, where malaria’s impact is greatest. We sought to (1) identify spatial and demographic patterns of FN-RDT results, defined as a negative RDT but positive gold standard microscopy test, and (2) estimate the percentage of infections missed within community-based malaria surveys due to FN-RDT results. Across all studies, 19.9% (95% CI 19.0% to 20.9%) of microscopy-positive subjects were negative by RDT. The distribution of FN-RDT results was spatially heterogeneous. The variance in FN-RDT results was best explained by the prevalence of malaria, with an increase in FN-RDT results observed at lower transmission intensities, among younger subjects, and in urban areas. The observed proportion of FN-RDT results was not predicted by differences in RDT brand or lot performance alone. These findings characterise how the probability of detection by RDTs varies in different transmission settings and emphasise the need for careful interpretation of prevalence estimates based on surveys employing RDTs alone. Further studies are needed to characterise the cost-effectiveness of improved malaria diagnostics (eg, PCR or highly sensitive RDTs) in community-based surveys, especially in regions of low transmission intensity or high urbanicity.
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Affiliation(s)
- Oliver J Watson
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
| | - Kelsey Marie Sumner
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Mark Janko
- Global Health Institute, Duke University, Durham, North Carolina, USA
| | - Varun Goel
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Peter Winskill
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
| | - Hannah C Slater
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
| | - Azra Ghani
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Jonathan B Parr
- Division of Infectious Diseases, Department of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
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Performance evaluation of different strategies based on microscopy techniques, rapid diagnostic test and molecular loop-mediated isothermal amplification assay for the diagnosis of imported malaria. Clin Microbiol Infect 2019; 26:115-121. [PMID: 31158521 DOI: 10.1016/j.cmi.2019.05.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 05/06/2019] [Accepted: 05/08/2019] [Indexed: 12/29/2022]
Abstract
OBJECTIVES Malaria is one of most common tropical diseases encountered in travellers and migrants. It requires an urgent and reliable diagnosis considering its potential severity. In this study, performance of five diagnostic assays were evaluated in a nonendemic region and compared prospectively to quantitative PCR (qPCR). METHODS A prospective study was conducted at Toulouse Hospital from August 2017 to January 2018 and included all patients with initial Plasmodium screening. Thin and thick blood smears (TnS, TkS), quantitative buffy coat (QBC), rapid diagnostic tests (RDTs) and commercial loop-mediated isothermal amplification (LAMP) were independently performed on each blood sample and compared to our qPCR reference standard. RESULTS The study encompassed 331 patients, mainly returning from Africa. qPCR detected 73 Plasmodium-positive samples (including 58 falciparum). Individually, LAMP had a 97.3% (71/73) sensitivity, far ahead of TnS (84.9%, 62/73), TkS (86.3%, 63/73), QBC (86.3%, 63/73) and RDT (86.3%, 63/73). RDT demonstrated a high sensitivity for falciparum (98.3%, 57/58) but missed all ovale, malariae and knowlesi infections. Specificity was excellent for all techniques (99.6-100%). The most sensitive diagnosis strategies were TnS + RDT (95.9%, 70/73), TnS + LAMP (97.3%, 71/73) and TnS + RDT + LAMP (100%, 73/73), about 10% higher than strategies using exclusively microscopy, TkS + TnS (87.7%, 64/73) or QBC + TnS (87.7%, 64/73). TnS remains necessary for Plasmodium species identification and quantification. Adding sequentially TnS only on LAMP-positive samples did not decrease TnS + LAMP strategy sensitivity. CONCLUSIONS In nonendemic countries, the currently recommended microscopy-based strategies seem unsatisfactory for malaria diagnosis considering RDT and LAMP performance, two rapid and sensitive assays that require limited training.
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Genome Mining-Based Identification of Identical Multirepeat Sequences in Plasmodium falciparum Genome for Highly Sensitive Real-Time Quantitative PCR Assay and Its Application in Malaria Diagnosis. J Mol Diagn 2019; 21:824-838. [PMID: 31158524 DOI: 10.1016/j.jmoldx.2019.04.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 04/02/2019] [Accepted: 04/30/2019] [Indexed: 11/21/2022] Open
Abstract
Developing ultrasensitive methods capable of detecting submicroscopic parasitemia-a challenge that persists in low transmission areas, asymptomatic carriers, and patients showing recrudescence-is vital to achieving malaria eradication. Nucleic acid amplification techniques offer improved analytical sensitivity but are limited by the number of copies of the amplification targets. Herein, we perform a novel genome mining approach to identify a pair of identical multirepeat sequences (IMRSs) that constitute 170 and 123 copies in the Plasmodium falciparum genome and explore their potential as primers for PCR. Real-time quantitative PCR analyses have shown the ability of P. falciparum IMRSs to amplify as low as 2.54 fg of P. falciparum genomic DNA (approximately 0.1 parasite), with a striking 100-fold increase in detection limit when compared with P. falciparum 18S rRNA (251.4 fg; approximately 10 parasites). Validation with clinical samples from malaria-endemic regions has shown 6.70 ± 1.66 cycle better detection threshold in terms of Ct value for P. falciparum IMRSs, with approximately 100% sensitivity and specificity. Plasmodium falciparum IMRS assays are also capable of detecting submicroscopic infections in asymptomatic samples. To summarize, this approach of initiating amplification at multiple loci across the genome and generating more products with increased analytical sensitivity is different from classic approaches amplifying multicopy genes or tandem repeats. This can serve as a platform technology to develop advanced diagnostics for various pathogens.
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35
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Affiliation(s)
- Peter A Zimmerman
- Professor of International Health, Genetics and Biology, The Center for Global Health & Diseases, Case Western Reserve University, Cleveland, Ohio
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36
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Amaral LC, Robortella DR, Guimarães LFF, Limongi JE, Fontes CJF, Pereira DB, de Brito CFA, Kano FS, de Sousa TN, Carvalho LH. Ribosomal and non-ribosomal PCR targets for the detection of low-density and mixed malaria infections. Malar J 2019; 18:154. [PMID: 31039781 PMCID: PMC6492410 DOI: 10.1186/s12936-019-2781-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 04/13/2019] [Indexed: 01/01/2023] Open
Abstract
Background The unexpected high proportion of submicroscopic malaria infections in areas with low transmission intensity challenges the control and elimination of malaria in the Americas. The current PCR-based assays present limitations as most protocols still rely on amplification of few-copies target gene. Here, the hypothesis was that amplification of different plasmodial targets—ribosomal (18S rRNA) and non-ribosomal multi-copy sequences (Pvr47 for Plasmodium vivax and Pfr364 for Plasmodium falciparum)—could increase the chances of detecting submicroscopic malaria infection. Methods A non-ribosomal real-time PCR assay targeting Pvr47/Pfr364 (NR-qPCR) was established and compared with three additional PCR protocols, two of them based on 18S rRNA gene amplification (Nested-PCR and R-qPCR) and one based on Pvr47/Pfr364 targets (NR-cPCR). The limit of detection of each PCR protocol, at single and artificial mixed P. vivax/P. falciparum infections, was determined by end-point titration curves. Field samples from clinical (n = 110) and subclinical (n = 324) malaria infections were used to evaluate the impact of using multiple molecular targets to detect malaria infections. Results The results demonstrated that an association of ribosomal and non-ribosomal targets did not increase sensitivity to detect submicroscopic malaria infections. Despite of that, artificial mixed-malaria infections demonstrated that the NR-qPCR was the most sensitive protocol to detect low-levels of P. vivax/P. falciparum co-infections. Field studies confirmed that submicroscopic malaria represented a large proportion (up to 77%) of infections among asymptomatic Amazonian residents, with a high proportion of infections (~ 20%) identified only by the NR-qPCR. Conclusions This study presents a new species-specific non-ribosomal PCR assay with potential to identify low-density P. vivax and P. falciparum infections. As the majority of subclinical infections was caused by P. vivax, the commonest form of malaria in the Amazon area, future studies should investigate the potential of Pvr47/Pfr364 to detect mixed-malaria infections in the field. Electronic supplementary material The online version of this article (10.1186/s12936-019-2781-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lara Cotta Amaral
- Instituto René Rachou, Fundação Oswaldo Cruz, FIOCRUZ-MINAS, Belo Horizonte, MG, Brazil
| | - Daniela Rocha Robortella
- Instituto René Rachou, Fundação Oswaldo Cruz, FIOCRUZ-MINAS, Belo Horizonte, MG, Brazil.,Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | | | | | - Dhelio Batista Pereira
- Centro de Pesquisas em Medicina Tropical de Rondônia (CEPEM), Porto Velho, Rondônia, Brazil
| | | | - Flora Satiko Kano
- Instituto René Rachou, Fundação Oswaldo Cruz, FIOCRUZ-MINAS, Belo Horizonte, MG, Brazil
| | - Taís Nóbrega de Sousa
- Instituto René Rachou, Fundação Oswaldo Cruz, FIOCRUZ-MINAS, Belo Horizonte, MG, Brazil.
| | - Luzia Helena Carvalho
- Instituto René Rachou, Fundação Oswaldo Cruz, FIOCRUZ-MINAS, Belo Horizonte, MG, Brazil. .,Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
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37
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Mangano VD, Perandin F, Tiberti N, Guerriero M, Migliaccio F, Prato M, Bargagna L, Tais S, Degani M, Verra F, Bisoffi Z, Bruschi F. Risk of transfusion-transmitted malaria: evaluation of commercial ELISA kits for the detection of anti-Plasmodium antibodies in candidate blood donors. Malar J 2019; 18:17. [PMID: 30670018 PMCID: PMC6341736 DOI: 10.1186/s12936-019-2650-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 01/14/2019] [Indexed: 11/10/2022] Open
Abstract
Background Transfusion with Plasmodium-infected blood represents a risk for malaria transmission, a rare but severe event. Several non-endemic countries implement a strategy for the screening of candidate blood donors including questionnaire for the identification of at-risk subjects and laboratory testing of blood samples, often serology-based, with temporary deferral from donation for individuals with a positive result. In Italy, the most recent legislation, issued in November 2015, introduced the use of serological tests for the detection of anti-Plasmodium antibodies. Methods In the absence of a gold standard for malaria serology, the aim of this work was to evaluate five commercial ELISA kits, and to determine their accuracy (sensitivity and specificity) in comparison to immuno-fluorescence antibody test (IFAT), and their agreement (concordance of results). Serum samples from malaria patients or from subjects with malaria history (N = 64), malaria naïve patients with other parasitic infections (N = 15), malaria naïve blood donors (N = 8) and malaria exposed candidate blood donors (N = 36) were tested. Results The specificity of all ELISA kits was 100%, while sensitivity ranged between 53 and 64% when compared to IFAT on malaria patients samples. When tested on candidate blood donors’ samples, ELISA kits showed highly variable agreement (42–94%) raising the possibility that the same individual could be included or excluded from donation depending on the test in use by the transfusion centre. Conclusions These preliminary results indicate how the lack of a gold standard for malaria serology must be taken into account in the application and future revision of current legislation. There is need of developing more sensitive serological assays. Moreover, the adoption of a unique serological test at national level is recommended, as well as the development of screening algorithms based on multiple laboratory tests, including molecular assays. Electronic supplementary material The online version of this article (10.1186/s12936-019-2650-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Valentina D Mangano
- Department of Translational Science, University of Pisa, Pisa, Italy.,Department of Laboratory Medicine, Pisa University Hospital, Pisa, Italy
| | - Francesca Perandin
- Centre for Tropical Diseases, IRCCS Sacro Cuore-Don Calabria Hospital, Negrar, Verona, Italy
| | - Natalia Tiberti
- Centre for Tropical Diseases, IRCCS Sacro Cuore-Don Calabria Hospital, Negrar, Verona, Italy
| | | | - Franca Migliaccio
- Department of Laboratory Medicine, Pisa University Hospital, Pisa, Italy
| | - Marco Prato
- Department of Laboratory Medicine, Pisa University Hospital, Pisa, Italy
| | - Lucia Bargagna
- Department of Laboratory Medicine, Pisa University Hospital, Pisa, Italy
| | - Stefano Tais
- Centre for Tropical Diseases, IRCCS Sacro Cuore-Don Calabria Hospital, Negrar, Verona, Italy
| | - Monica Degani
- Centre for Tropical Diseases, IRCCS Sacro Cuore-Don Calabria Hospital, Negrar, Verona, Italy
| | - Federica Verra
- Centre for Tropical Diseases, IRCCS Sacro Cuore-Don Calabria Hospital, Negrar, Verona, Italy
| | - Zeno Bisoffi
- Centre for Tropical Diseases, IRCCS Sacro Cuore-Don Calabria Hospital, Negrar, Verona, Italy. .,Department of Diagnostic and Public Health, University of Verona, Policlinico "G. B. Rossi", Verona, Italy.
| | - Fabrizio Bruschi
- Department of Translational Science, University of Pisa, Pisa, Italy. .,Department of Laboratory Medicine, Pisa University Hospital, Pisa, Italy.
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Cheaveau J, Nguyen H, Chow B, Marasinghe D, Mohon AN, Yuan H, Viana G, van Schalkwyk D, Church D, Chan W, Pillai DR. Clinical Validation of a Commercial LAMP Test for Ruling out Malaria in Returning Travelers: A Prospective Diagnostic Trial. Open Forum Infect Dis 2018; 5:ofy260. [PMID: 30465012 PMCID: PMC6239078 DOI: 10.1093/ofid/ofy260] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 10/08/2018] [Indexed: 12/21/2022] Open
Abstract
The mainstay of malaria diagnosis relies on rapid diagnostic tests (RDTs) and microscopy, both of which lack analytical sensitivity. This leads to repeat testing to rule out malaria. A prospective diagnostic trial of the Meridian illumigene Malaria assay (loop-mediated isothermal amplification [LAMP]) was conducted comparing it with reference microscopy and RDTs (BinaxNOW Malaria) in returning travelers between June 2017 and January 2018. Returning travelers with signs and symptoms of malaria were enrolled in the study. RDTs, microscopy, and LAMP assays were performed simultaneously. A total of 298 patients (50.7% male; mean age, 32.5 years) were enrolled, most visiting friends and relatives (43.3%), presenting with fever (88.9%), not taking prophylaxis (82.9%), and treated as outpatients (84.1%). In the prospective arm (n = 348), LAMP had a sensitivity of 98.1% (95% confidence interval [CI], 90.0%–100%) and a specificity of 97.6% (95% CI, 95.2%–99.1%) vs microscopy. After discrepant resolution with real-time polymerase chain reaction, LAMP had a sensitivity of 100% (95% CI, 93.7%–100%) and a specificity of 100% (95% CI, 98.7%–100%) vs microscopy. After discrepant resolution, RDTs had a sensitivity of 83.3% (95% CI, 58.6%–96.4%) and a specificity of 96.2% (95% CI, 93.2%–98.1%) vs microscopy. When including retrospective specimens (n = 377), LAMP had a sensitivity of 98.8% (95% CI, 93.2%–100%) and a specificity of 97.6% (95% CI, 95.2%–99.1%) vs microscopy, and after discrepant resolution of this set, LAMP had a sensitivity of 100% (95% CI, 95.8%–100%) and a specificity of 100% (95% CI, 98.7%–100%). A cost-benefit analysis of reagents and labor suggests savings of up to USD$13 per specimen using a novel algorithm with LAMP screening.
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Affiliation(s)
- James Cheaveau
- Clinical Section of Microbiology, Calgary Laboratory Services, Calgary, Alberta, Canada.,Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Alberta, Canada
| | - Hong Nguyen
- Clinical Section of Microbiology, Calgary Laboratory Services, Calgary, Alberta, Canada
| | - Barbara Chow
- Clinical Section of Microbiology, Calgary Laboratory Services, Calgary, Alberta, Canada
| | - Dewdunee Marasinghe
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada
| | - Abu Naser Mohon
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Alberta, Canada.,Laboratório de Pesquisas em Malária, Instituto Evandro Chagas, Levilândia Ananindeua, Pará, Brasil
| | - Hong Yuan
- ProvLab Alberta, Edmonton, Alberta, Canada
| | - Gisele Viana
- Laboratório de Pesquisas em Malária, Instituto Evandro Chagas, Levilândia Ananindeua, Pará, Brasil
| | - Donelly van Schalkwyk
- Department of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Deirdre Church
- Clinical Section of Microbiology, Calgary Laboratory Services, Calgary, Alberta, Canada.,Department Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Wilson Chan
- Clinical Section of Microbiology, Calgary Laboratory Services, Calgary, Alberta, Canada.,Department Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Dylan R Pillai
- Clinical Section of Microbiology, Calgary Laboratory Services, Calgary, Alberta, Canada.,Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Alberta, Canada.,Department Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Medicine, University of Calgary, Calgary, Alberta, Canada
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Ita OI, Otu AA, Onyedibe K, Iwuafor AA, Banwat E, Egah DZ. A diagnostic performance evaluation of rapid diagnostic tests and microscopy for malaria diagnosis using nested polymerase chain reaction as reference standard in a tertiary hospital in Jos, Nigeria. Trans R Soc Trop Med Hyg 2018; 112:436-442. [DOI: 10.1093/trstmh/try071] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 06/19/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Okokon I Ita
- Department of Medical Microbiology and Parasitology, University of Calabar, Calabar, Cross River State
| | - Akaninyene A Otu
- Department of Internal Medicine, University of Calabar, Calabar, Cross River State, Nigeria
- National Aspergillosis Centre, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Kenneth Onyedibe
- Department of Medical Microbiology and Parasitology, University of Jos, Plateau State, Nigeria
| | - Anthony A Iwuafor
- Department of Medical Microbiology and Parasitology, University of Calabar, Calabar, Cross River State
| | - Edmund Banwat
- Department of Medical Microbiology and Parasitology, University of Jos, Plateau State, Nigeria
| | - Daniel Z Egah
- Department of Medical Microbiology and Parasitology, University of Jos, Plateau State, Nigeria
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40
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Kang SY, Battle KE, Gibson HS, Ratsimbasoa A, Randrianarivelojosia M, Ramboarina S, Zimmerman PA, Weiss DJ, Cameron E, Gething PW, Howes RE. Spatio-temporal mapping of Madagascar's Malaria Indicator Survey results to assess Plasmodium falciparum endemicity trends between 2011 and 2016. BMC Med 2018; 16:71. [PMID: 29788968 PMCID: PMC5964908 DOI: 10.1186/s12916-018-1060-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 04/24/2018] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Reliable measures of disease burden over time are necessary to evaluate the impact of interventions and assess sub-national trends in the distribution of infection. Three Malaria Indicator Surveys (MISs) have been conducted in Madagascar since 2011. They provide a valuable resource to assess changes in burden that is complementary to the country's routine case reporting system. METHODS A Bayesian geostatistical spatio-temporal model was developed in an integrated nested Laplace approximation framework to map the prevalence of Plasmodium falciparum malaria infection among children from 6 to 59 months in age across Madagascar for 2011, 2013 and 2016 based on the MIS datasets. The model was informed by a suite of environmental and socio-demographic covariates known to influence infection prevalence. Spatio-temporal trends were quantified across the country. RESULTS Despite a relatively small decrease between 2013 and 2016, the prevalence of malaria infection has increased substantially in all areas of Madagascar since 2011. In 2011, almost half (42.3%) of the country's population lived in areas of very low malaria risk (<1% parasite prevalence), but by 2016, this had dropped to only 26.7% of the population. Meanwhile, the population in high transmission areas (prevalence >20%) increased from only 2.2% in 2011 to 9.2% in 2016. A comparison of the model-based estimates with the raw MIS results indicates there was an underestimation of the situation in 2016, since the raw figures likely associated with survey timings were delayed until after the peak transmission season. CONCLUSIONS Malaria remains an important health problem in Madagascar. The monthly and annual prevalence maps developed here provide a way to evaluate the magnitude of change over time, taking into account variability in survey input data. These methods can contribute to monitoring sub-national trends of malaria prevalence in Madagascar as the country aims for geographically progressive elimination.
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Affiliation(s)
- Su Yun Kang
- Malaria Atlas Project, Oxford Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Katherine E Battle
- Malaria Atlas Project, Oxford Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Harry S Gibson
- Malaria Atlas Project, Oxford Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Arsène Ratsimbasoa
- National Malaria Control Programme, Ministry of Health, Antananarivo, Madagascar.,University of Antananarivo, Antananarivo, Madagascar
| | - Milijaona Randrianarivelojosia
- Institut Pasteur de Madagascar, Antananarivo, Madagascar.,Faculté des Sciences, Université de Toliara, Toliara, Madagascar
| | - Stéphanie Ramboarina
- National Malaria Control Programme, Ministry of Health, Antananarivo, Madagascar.,University of Antananarivo, Antananarivo, Madagascar.,Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
| | - Peter A Zimmerman
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
| | - Daniel J Weiss
- Malaria Atlas Project, Oxford Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Ewan Cameron
- Malaria Atlas Project, Oxford Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Peter W Gething
- Malaria Atlas Project, Oxford Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Rosalind E Howes
- Malaria Atlas Project, Oxford Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK. .,Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA.
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Willie N, Mehlotra RK, Howes RE, Rakotomanga TA, Ramboarina S, Ratsimbasoa AC, Zimmerman PA. Insights into the Performance of SD Bioline Malaria Ag P.f/Pan Rapid Diagnostic Test and Plasmodium falciparum Histidine-Rich Protein 2 Gene Variation in Madagascar. Am J Trop Med Hyg 2018; 98:1683-1691. [PMID: 29557337 DOI: 10.4269/ajtmh.17-0845] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Plasmodium falciparum histidine-rich protein 2 (PfHRP2) forms the basis of many current malaria rapid diagnostic tests (RDTs). However, the parasites lacking part or all of the pfhrp2 gene do not express the PfHRP2 protein and are, therefore, not identifiable by PfHRP2-detecting RDTs. We evaluated the performance of the SD Bioline Malaria Ag P.f/Pan RDT together with pfhrp2 variation in Madagascar. Genomic DNA isolated from 260 patient blood samples were polymerase chain reaction (PCR)-amplified for the parasite 18S rRNA and pfhrp2 genes. Post-PCR ligation detection reaction-fluorescent microsphere assay (LDR-FMA) was performed for the identification of parasite species. Plasmodium falciparum histidine-rich protein 2 amplicons were sequenced. Polymerase chain reaction diagnosis of patient samples showed that 29% (75/260) were infected and P. falciparum was present in 95% (71/75) of these PCR-positive samples. Comparing RDT and P. falciparum detection by LDR-FMA, eight samples were RDT negative but P. falciparum positive (false negatives), all of which were pfhrp2 positive. The sensitivity and specificity of the RDT were 87% and 90%, respectively. Seventy-three samples were amplified for pfhrp2, from which nine randomly selected amplicons were sequenced, yielding 13 sequences. Amplification of pfhrp2, combined with RDT analysis and P. falciparum detection by LDR-FMA, showed that there was no indication of pfhrp2 deletion. Sequence analysis of pfhrp2 showed that the correlation between pfhrp2 sequence structure and RDT detection rates was unclear. Although the observed absence of pfhrp2 deletion from the samples screened here is encouraging, continued monitoring of the efficacy of the SD Bioline Malaria Ag P.f/Pan RDT for malaria diagnosis in Madagascar is warranted.
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Affiliation(s)
- Nigani Willie
- Center for Global Health and Diseases, School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Rajeev K Mehlotra
- Center for Global Health and Diseases, School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Rosalind E Howes
- Nuffield Department of Medicine, Oxford Big Data Institute, University of Oxford, Oxford, United Kingdom.,Center for Global Health and Diseases, School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Tovonahary A Rakotomanga
- Faculty of Sciences, University of Antananarivo, Antananarivo, Madagascar.,National Malaria Control Programme, Ministry of Health, Antananarivo, Madagascar
| | - Stephanie Ramboarina
- Faculty of Sciences, University of Antananarivo, Antananarivo, Madagascar.,Center for Global Health and Diseases, School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Arsène C Ratsimbasoa
- Faculty of Sciences, University of Antananarivo, Antananarivo, Madagascar.,National Malaria Control Programme, Ministry of Health, Antananarivo, Madagascar
| | - Peter A Zimmerman
- Center for Global Health and Diseases, School of Medicine, Case Western Reserve University, Cleveland, Ohio
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Gopakumar GP, Swetha M, Sai Siva G, Sai Subrahmanyam GRK. Convolutional neural network-based malaria diagnosis from focus stack of blood smear images acquired using custom-built slide scanner. JOURNAL OF BIOPHOTONICS 2018; 11:e201700003. [PMID: 28851134 DOI: 10.1002/jbio.201700003] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 07/23/2017] [Accepted: 08/24/2017] [Indexed: 05/24/2023]
Abstract
The present paper introduces a focus stacking-based approach for automated quantitative detection of Plasmodium falciparum malaria from blood smear. For the detection, a custom designed convolutional neural network (CNN) operating on focus stack of images is used. The cell counting problem is addressed as the segmentation problem and we propose a 2-level segmentation strategy. Use of CNN operating on focus stack for the detection of malaria is first of its kind, and it not only improved the detection accuracy (both in terms of sensitivity [97.06%] and specificity [98.50%]) but also favored the processing on cell patches and avoided the need for hand-engineered features. The slide images are acquired with a custom-built portable slide scanner made from low-cost, off-the-shelf components and is suitable for point-of-care diagnostics. The proposed approach of employing sophisticated algorithmic processing together with inexpensive instrumentation can potentially benefit clinicians to enable malaria diagnosis.
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Affiliation(s)
| | - Murali Swetha
- Department of Instrumentation and Applied Physics, Indian Institute of Science, Bengaluru, India
| | - Gorthi Sai Siva
- Department of Instrumentation and Applied Physics, Indian Institute of Science, Bengaluru, India
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43
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Malaria Disease Recommendations for Solid Organ Transplant Recipients and Donors. Transplantation 2018; 102:S16-S26. [DOI: 10.1097/tp.0000000000002017] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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44
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Patankar S, Sharma S, Rathod PK, Duraisingh MT. Malaria in India: The Need for New Targets for Diagnosis and Detection of Plasmodium vivax. Proteomics Clin Appl 2018; 12:e1700024. [PMID: 29193853 DOI: 10.1002/prca.201700024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 08/28/2017] [Indexed: 11/08/2022]
Abstract
Plasmodium vivax is a protozoan parasite that is one of the causative agents of human malaria. Due to several occult features of its life cycle, P. vivax threatens to be a problem for the recent efforts toward elimination of malaria globally. With an emphasis on malaria elimination goals, the authors summarize the major gaps in P. vivax diagnosis and describe how proteomics technologies have begun to contribute toward the discovery of antigens that could be used for various technology platforms and applications. The authors suggest areas where, in the future, proteomics technologies could fill in gaps in P. vivax diagnosis that have proved difficult. The discovery of new parasite antigens, host responses, and immune signatures using proteomics technologies will be a key part of the global malaria elimination efforts.
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Affiliation(s)
- Swati Patankar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India.,Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Shobhona Sharma
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | | | - Manoj T Duraisingh
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
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45
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Kolluri N, Klapperich CM, Cabodi M. Towards lab-on-a-chip diagnostics for malaria elimination. LAB ON A CHIP 2017; 18:75-94. [PMID: 29125615 DOI: 10.1039/c7lc00758b] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Malaria continues to be one of the most devastating diseases impacting global health. Although there have been significant reductions in global malaria incidence and mortality rates over the past 17 years, the disease remains endemic throughout the world, especially in low- and middle-income countries. The World Health Organization has put forth ambitious milestones moving toward a world free of malaria as part of the United Nations Millennium Goals. Mass screening and treatment of symptomatic and asymptomatic malaria infections in endemic regions is integral to these goals and requires diagnostics that are both sensitive and affordable. Lab-on-a-chip technologies provide a path toward sensitive, portable, and affordable diagnostic platforms. Here, we review and compare currently-available and emerging lab-on-a-chip diagnostic approaches in three categories: (1) protein-based tests, (2) nucleic acid tests, and (3) cell-based detection. For each category, we highlight the opportunities and challenges in diagnostics development for malaria elimination, and comment on their applicability to different phases of elimination strategies.
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Affiliation(s)
- N Kolluri
- Department of Biomedical Engineering, Boston University, Boston, MA, USA.
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46
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Ponce C, Kaczorowski F, Perpoint T, Miailhes P, Sigal A, Javouhey E, Gillet Y, Jacquin L, Douplat M, Tazarourte K, Potinet V, Simon B, Lavoignat A, Bonnot G, Sow F, Bienvenu AL, Picot S. Diagnostic accuracy of loop-mediated isothermal amplification (LAMP) for screening patients with imported malaria in a non-endemic setting. ACTA ACUST UNITED AC 2017; 24:53. [PMID: 29251261 PMCID: PMC5734902 DOI: 10.1051/parasite/2017054] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 11/29/2017] [Indexed: 11/14/2022]
Abstract
BACKGROUND Sensitive and easy-to-perform methods for the diagnosis of malaria are not yet available. Improving the limit of detection and following the requirements for certification are issues to be addressed in both endemic and non-endemic settings. The aim of this study was to test whether loop-mediated isothermal amplification of DNA (LAMP) may be an alternative to microscopy or real-time PCR for the screening of imported malaria cases in non-endemic area. RESULTS 310 blood samples associated with 829 suspected cases of imported malaria were tested during a one year period. Microscopy (thin and thick stained blood slides, reference standard) was used for the diagnosis. Real-time PCR was used as a standard of truth, and LAMP (Meridian Malaria Plus) was used as an index test in a prospective study conducted following the Standards for Reporting Diagnosis Accuracy Studies. In the 83 positive samples, species identification was P. falciparum (n = 66), P. ovale (n = 9), P. vivax (n = 3) P. malariae (n = 3) and 2 co-infections with P. falciparum + P.malariae. Using LAMP methods, 93 samples gave positive results, including 4 false-positives. Sensitivity, specificity, positive predictive value and negative predictive value for LAMP tests were 100%, 98.13%, 95.51%, and 100% compared to PCR. CONCLUSION High negative predictive value, and limit of detection suggest that LAMP can be used for screening of imported malaria cases in non-endemic countries when expert microscopists are not immediately available. However, the rare occurrence of non-valid results and the need for species identification and quantification of positive samples preclude the use of LAMP as a single reference method.
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Affiliation(s)
- Camille Ponce
- Institute of Parasitology and Medical Mycology, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, 69004 Lyon, France
| | - Flora Kaczorowski
- Institute of Parasitology and Medical Mycology, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, 69004 Lyon, France
| | - Thomas Perpoint
- Service des Maladies Infectieuses et Tropicales, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, 69004 Lyon, France
| | - Patrick Miailhes
- Service des Maladies Infectieuses et Tropicales, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, 69004 Lyon, France
| | - Alain Sigal
- Service d'accueil des Urgences, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, 69004 Lyon, France
| | - Etienne Javouhey
- Service d'accueil des Urgences Pédiatriques, Hôpital Femme-Mère-Enfant, Hospices Civils de Lyon, 69677 Bron, France
| | - Yves Gillet
- Service d'accueil des Urgences Pédiatriques, Hôpital Femme-Mère-Enfant, Hospices Civils de Lyon, 69677 Bron, France
| | - Laurent Jacquin
- Service d'accueil des urgences, Hôpital Edouard Herriot, Hospices Civils de Lyon, 69003 Lyon, France
| | - Marion Douplat
- Service d'accueil des urgences, Hôpital Lyon Sud, Hospices Civils de Lyon, Hôpital Lyon Sud, 69310 Pierre-Bénite, France
| | - Karim Tazarourte
- Service des urgences/SAMU 69, Hospices Civils de Lyon, Lyon, 69003, France - Univ. Lyon, Université Claude Bernard Lyon 1, HESPER EA 7425, 69008 Lyon, France
| | - Véronique Potinet
- Service d'accueil des urgences, Hôpital Lyon Sud, Hospices Civils de Lyon, Hôpital Lyon Sud, 69310 Pierre-Bénite, France
| | - Bruno Simon
- Institute of Parasitology and Medical Mycology, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, 69004 Lyon, France
| | - Adeline Lavoignat
- Malaria Research Unit, SMITh, ICBMS, UMR 5246 CNRS-INSA-CPE-University Lyon1, 69100 Villeurbanne, France
| | - Guillaume Bonnot
- Malaria Research Unit, SMITh, ICBMS, UMR 5246 CNRS-INSA-CPE-University Lyon1, 69100 Villeurbanne, France
| | - Fatimata Sow
- Malaria Research Unit, SMITh, ICBMS, UMR 5246 CNRS-INSA-CPE-University Lyon1, 69100 Villeurbanne, France
| | - Anne-Lise Bienvenu
- Malaria Research Unit, SMITh, ICBMS, UMR 5246 CNRS-INSA-CPE-University Lyon1, 69100 Villeurbanne, France - Laboratoire d'Hématologie, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, 69004 Lyon, France
| | - Stéphane Picot
- Institute of Parasitology and Medical Mycology, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, 69004 Lyon, France - Malaria Research Unit, SMITh, ICBMS, UMR 5246 CNRS-INSA-CPE-University Lyon1, 69100 Villeurbanne, France
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Abstract
Basic science holds enormous power for revealing the biological mechanisms of disease and, in turn, paving the way toward new, effective interventions. Recognizing this power, the 2011 Research Agenda for Malaria Eradication included key priorities in fundamental research that, if attained, could help accelerate progress toward disease elimination and eradication. The Malaria Eradication Research Agenda (malERA) Consultative Panel on Basic Science and Enabling Technologies reviewed the progress, continuing challenges, and major opportunities for future research. The recommendations come from a literature of published and unpublished materials and the deliberations of the malERA Refresh Consultative Panel. These areas span multiple aspects of the Plasmodium life cycle in both the human host and the Anopheles vector and include critical, unanswered questions about parasite transmission, human infection in the liver, asexual-stage biology, and malaria persistence. We believe an integrated approach encompassing human immunology, parasitology, and entomology, and harnessing new and emerging biomedical technologies offers the best path toward addressing these questions and, ultimately, lowering the worldwide burden of malaria.
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Abstract
Malaria is a mosquito-borne disease caused by five species of Plasmodium parasites. Accurate diagnosis of malaria plays an essential part in malaria control. With traditional diagnostic methodologies, malaria control programs have achieved remarkable success during the past decade, and are now heading toward malaria elimination in many areas. This new situation, however, calls for novel diagnostics with improved sensitivity, throughput, and reduced cost for active screening of malaria parasites, as all transfected individuals have to be identified in order to block transmission. In this chapter, we provide a brief introduction of malaria, the requirement of diagnostic advances in the age of malaria elimination, and a comprehensive overview of the currently available molecular malaria diagnostics, ranging from well-known tests to platforms in early stages of evaluation. We also discussed several practical issues for the application of molecular tests in malaria identification.
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49
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Howes RE, Battle KE, Mendis KN, Smith DL, Cibulskis RE, Baird JK, Hay SI. Global Epidemiology of Plasmodium vivax. Am J Trop Med Hyg 2016; 95:15-34. [PMID: 27402513 PMCID: PMC5198891 DOI: 10.4269/ajtmh.16-0141] [Citation(s) in RCA: 253] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 04/19/2016] [Indexed: 01/09/2023] Open
Abstract
Plasmodium vivax is the most widespread human malaria, putting 2.5 billion people at risk of infection. Its unique biological and epidemiological characteristics pose challenges to control strategies that have been principally targeted against Plasmodium falciparum Unlike P. falciparum, P. vivax infections have typically low blood-stage parasitemia with gametocytes emerging before illness manifests, and dormant liver stages causing relapses. These traits affect both its geographic distribution and transmission patterns. Asymptomatic infections, high-risk groups, and resulting case burdens are described in this review. Despite relatively low prevalence measurements and parasitemia levels, along with high proportions of asymptomatic cases, this parasite is not benign. Plasmodium vivax can be associated with severe and even fatal illness. Spreading resistance to chloroquine against the acute attack, and the operational inadequacy of primaquine against the multiple attacks of relapse, exacerbates the risk of poor outcomes among the tens of millions suffering from infection each year. Without strategies accounting for these P. vivax-specific characteristics, progress toward elimination of endemic malaria transmission will be substantially impeded.
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Affiliation(s)
- Rosalind E. Howes
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Katherine E. Battle
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Kamini N. Mendis
- Global Malaria Program, World Health Organization, Geneva, Switzerland
| | - David L. Smith
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland
- Sanaria Institute for Global Health and Tropical Medicine, Rockville, Maryland
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, Washington
| | | | - J. Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Simon I. Hay
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, Washington
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, United Kingdom
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50
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Sensitive and accurate quantification of human malaria parasites using droplet digital PCR (ddPCR). Sci Rep 2016; 6:39183. [PMID: 27982132 PMCID: PMC5159915 DOI: 10.1038/srep39183] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 11/18/2016] [Indexed: 12/21/2022] Open
Abstract
Accurate quantification of parasite density in the human host is essential for understanding the biology and pathology of malaria. Semi-quantitative molecular methods are widely applied, but the need for an external standard curve makes it difficult to compare parasite density estimates across studies. Droplet digital PCR (ddPCR) allows direct quantification without the need for a standard curve. ddPCR was used to diagnose and quantify P. falciparum and P. vivax in clinical patients as well as in asymptomatic samples. ddPCR yielded highly reproducible measurements across the range of parasite densities observed in humans, and showed higher sensitivity than qPCR to diagnose P. falciparum, and equal sensitivity for P. vivax. Correspondence in quantification was very high (>0.95) between qPCR and ddPCR. Quantification between technical replicates by ddPCR differed 1.5-1.7-fold, compared to 2.4-6.2-fold by qPCR. ddPCR facilitates parasite quantification for studies where absolute densities are required, and will increase comparability of results reported from different laboratories.
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