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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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2
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Aggarwal S, Selvaraj S, Subramanian JN, Vijayalakshmi MA, Patankar S, Srivastava S. Polyclonal Antibody Generation against PvTRAg for the Development of a Diagnostic Assay for Plasmodium vivax. Diagnostics (Basel) 2023; 13:diagnostics13050835. [PMID: 36899977 PMCID: PMC10001162 DOI: 10.3390/diagnostics13050835] [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: 11/12/2022] [Revised: 01/15/2023] [Accepted: 02/10/2023] [Indexed: 02/24/2023] Open
Abstract
The World Health Organization (WHO) has set forth a global call for eradicating malaria, caused majorly by the protozoan parasites Plasmodium falciparum and Plasmodium vivax. The lack of diagnostic biomarkers for P. vivax, especially those that differentiate the parasite from P. falciparum, significantly hinders P. vivax elimination. Here, we show that P. vivax tryptophan-rich antigen (PvTRAg) can be a diagnostic biomarker for diagnosing P. vivax in malaria patients. We report that polyclonal antibodies against purified PvTRAg protein show interactions with purified PvTRAg and native PvTRAg using Western blots and indirect enzyme-linked immunosorbent assay (ELISA). We also developed an antibody-antigen-based qualitative assay using biolayer interferometry (BLI) to detect vivax infection using plasma samples from patients with different febrile diseases and healthy controls. The polyclonal anti-PvTRAg antibodies were used to capture free native PvTRAg from the patient plasma samples using BLI, providing a new expansion range to make the assay quick, accurate, sensitive, and high-throughput. The data presented in this report provides a proof of concept for PvTRAg, a new antigen, for developing a diagnostic assay for P. vivax identification and differentiation from the rest of the Plasmodium species and, at a later stage, translating the BLI assay into affordable, point-of-care formats to make it more accessible.
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Affiliation(s)
- Shalini Aggarwal
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610010, Israel
| | - Selvamano Selvaraj
- Centre for Bio-Separation Technology, Vellore Institute of Technology, Vellore 632014, India
| | | | | | - Swati Patankar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Sanjeeva Srivastava
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
- Correspondence: ; Tel.: +91-(22)-2576-7779
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3
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Kaur D, Sinha S, Sehgal R. Global scenario of Plasmodium vivax occurrence and resistance pattern. J Basic Microbiol 2022; 62:1417-1428. [PMID: 36125207 DOI: 10.1002/jobm.202200316] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/20/2022] [Accepted: 09/04/2022] [Indexed: 11/06/2022]
Abstract
Malaria caused by Plasmodium vivax is comparatively less virulent than Plasmodium falciparum, which can also lead to severe disease and death. It shows a wide geographical distribution. Chloroquine serves as a drug of choice, with primaquine as a radical cure. However, with the appearance of resistance to chloroquine and treatment has been shifted to artemisinin combination therapy followed by primaquine as a radical cure. Sulphadoxine-pyrimethamine, mefloquine, and atovaquone-proguanil are other drugs of choice in chloroquine-resistant areas, and later resistance was soon reported for these drugs also. The emergence of drug resistance serves as a major hurdle to controlling and eliminating malaria. The discovery of robust molecular markers and regular surveillance for the presence of mutations in malaria-endemic areas would serve as a helpful tool to combat drug resistance. Here, in this review, we will discuss the endemicity of P. vivax, a historical overview of antimalarial drugs, the appearance of drug resistance and molecular markers with their global distribution along with different measures taken to reduce malaria burden due to P. vivax infection and their resistance.
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Affiliation(s)
- Davinder Kaur
- Department of Medical Parasitology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Shweta Sinha
- Department of Medical Parasitology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Rakesh Sehgal
- Department of Medical Parasitology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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4
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Abate A, Assefa M, Golassa L. Five-Year Trend of Malaria Prevalence in Mojo Town, Central Ethiopia: Shifting Burden of the Disease and Its Implication for Malaria Elimination: A Retrospective Study. Infect Drug Resist 2022; 15:455-464. [PMID: 35177912 PMCID: PMC8846561 DOI: 10.2147/idr.s348203] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 02/05/2022] [Indexed: 12/16/2022] Open
Abstract
Introduction Malaria continues to strike hardest against the health and economic development in Ethiopia. The peak of malaria incidence follows the main rainfall season in each year; however, its transmission tends to be highly heterogeneous within or between years and from area to area. Thus, this study was aimed to determine the trend prevalence of malaria in Mojo town, central Ethiopia. Methods A retrospective study was conducted in Mojo town, East Shoa zone, Ethiopia from February to March 2021. Malaria cases and related data documented between 2016 and 2020 were carefully reviewed from laboratory registration logbooks. The collected data were analyzed using descriptive statistics. Results A total of 19,106 blood films were examined from malaria-suspected patients. The overall microscopically confirmed prevalence of malaria was 4.2% (793/19,106). Plasmodium vivax was the predominant species accounting for 76.2% (604/793) of positive samples. Malaria cases declined from 259 in 2016 to 77 in 2020. The proportion of malaria was higher among males (64.8%, 514/793) than females (35.2%, 279/793) (P < 0.0001). Higher malaria cases were observed from the age group 15–24 years followed by the age group of 25–34 (P < 0.0001). The number of malaria cases was at a high level from September to November and lowest from December to February. Conclusion Despite a declining trend of malaria prevalence, it remains a public health burden in the area. P. vivax, the predominant species, should get attention during prevention and control strategies for the successful progress of the malaria elimination program.
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Affiliation(s)
- Andargie Abate
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
- College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia
- Correspondence: Andargie Abate, Email
| | - Mesfin Assefa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
- College of Medicine and Health Sciences, Wachamo University, Hossaena, Ethiopia
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
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5
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Abstract
J. Kevin Baird and colleagues, examine and discuss the estimated global burden of vivax malaria and it's biological, clinical, and public health complexity.
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Affiliation(s)
- Katherine E. Battle
- Institute for Disease Modeling, Seattle, Washington, United States of America
| | - J. Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Eijkman Institute of Molecular Biology, Jakarta, Indonesia
- Nuffield Department of Medicine, Centre for Tropical Medicine, University of Oxford, Oxford, United Kingdom
- * E-mail:
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6
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The New Zoonotic Malaria: Plasmodium cynomolgi. Trop Med Infect Dis 2021; 6:tropicalmed6020046. [PMID: 33916448 PMCID: PMC8167800 DOI: 10.3390/tropicalmed6020046] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 04/02/2021] [Accepted: 04/03/2021] [Indexed: 12/04/2022] Open
Abstract
Plasmodium cynomolgi is a simian malaria parasite that has been a central model parasite since it was first described in 1907. Recently it has made the zoonotic jump and started naturally infecting humans. In this paper, the interactions between Plasmodium cynomolgi and humans, the environment and the non-human animal intermediates or definitive host will be discussed, with a particular focus on the clinical implications of infection and approaches to management of this novel zoonotic parasite.
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7
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Nguyen TT, Nguyen XX, Ronse M, Nguyen QT, Ho PQ, Tran DT, Gerrets R, Thriemer K, Ley B, Marfurt J, Price RN, Grietens KP, Gryseels C. Diagnostic Practices and Treatment for P. vivax in the InterEthnic Therapeutic Encounter of South-Central Vietnam: A Mixed-Methods Study. Pathogens 2020; 10:pathogens10010026. [PMID: 33396538 PMCID: PMC7824694 DOI: 10.3390/pathogens10010026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/25/2020] [Accepted: 12/28/2020] [Indexed: 01/13/2023] Open
Abstract
Malaria elimination in the Greater Mekong Sub-Region is challenged by a rising proportion of malaria attributable to P. vivax. Primaquine (PQ) is effective in eliminating the parasite's dormant liver stages and can prevent relapsing infections, but it induces severe haemolysis in patients with Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency, highlighting the importance of testing enzyme activity prior to treatment. A mixed-method study was conducted in south-central Vietnam to explore the factors that affect acceptability of G6PD testing, treatment-seeking behaviors, and adherence to current regimens. The majority of respondents (75.7%) were unaware of the different parasite species and rather differentiated malaria by perceived severity. People sought a diagnosis if suspected of malaria fever but not if they perceived their fevers as mild. Most respondents agreed to take prescribed medication to treat asymptomatic infection (94.1%) and to continue medication even if they felt better (91.5%). Health professionals did not have G6PD diagnostic tools nor the means to prescribe PQ safely. Adherence to treatment was linked to trust in public providers, who were perceived to make therapeutic decisions in the interest of the patient. Greater focus on providing acceptable ways of assessing G6PD deficiency will be needed to ensure the timely elimination of malaria in Vietnam.
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Affiliation(s)
- Thuan Thi Nguyen
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium; (M.R.); (K.P.G.); (C.G.)
- Correspondence: ; Tel.: +324-9679-1347
| | - Xa Xuan Nguyen
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
| | - Maya Ronse
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium; (M.R.); (K.P.G.); (C.G.)
| | - Quynh Truc Nguyen
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
| | - Phuc Quang Ho
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
| | - Duong Thanh Tran
- National Institute of Malariology, Parasitology and Entomology (NIMPE), 34 Trung Van, Trung Van Ward, Nam Tu Liem District, Hanoi 10000, Vietnam; (X.X.N.); (Q.T.N.); (P.Q.H.); (D.T.T.)
| | - Rene Gerrets
- Amsterdam Institute for Social Science Research (AISSR), University of Amsterdam, Postbus 15718, 1001 NE Amsterdam, The Netherlands;
- Amsterdam Institute for Global Health and Development (AIGHD), AHTC, Tower C4, Paasheuvelweg 25, 1105 BP Amsterdam, The Netherlands
| | - Kamala Thriemer
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Rocklands Drive Casuarina, Darwin Northern Territory 0810, Australia; (K.T.); (B.L.); (J.M.); (R.N.P.)
| | - Benedikt Ley
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Rocklands Drive Casuarina, Darwin Northern Territory 0810, Australia; (K.T.); (B.L.); (J.M.); (R.N.P.)
| | - Jutta Marfurt
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Rocklands Drive Casuarina, Darwin Northern Territory 0810, Australia; (K.T.); (B.L.); (J.M.); (R.N.P.)
| | - Ric N. Price
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Rocklands Drive Casuarina, Darwin Northern Territory 0810, Australia; (K.T.); (B.L.); (J.M.); (R.N.P.)
- Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7LG, UK
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Koen Peeters Grietens
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium; (M.R.); (K.P.G.); (C.G.)
| | - Charlotte Gryseels
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium; (M.R.); (K.P.G.); (C.G.)
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8
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Albrecht L, Lopes SCP, da Silva ABIE, Barbosa V, Almeida RP, Siqueira AM, Leite JA, Bittencourt NC, Dos Santos HG, Bourgard C, Garcia LFC, Kayano ACAV, Soares IS, Russell B, Rénia L, Lacerda MVG, Costa FTM. Rosettes integrity protects Plasmodium vivax of being phagocytized. Sci Rep 2020; 10:16706. [PMID: 33028898 PMCID: PMC7541459 DOI: 10.1038/s41598-020-73713-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 08/27/2020] [Indexed: 01/18/2023] Open
Abstract
Plasmodium vivax is the most prevalent cause of malaria outside of Africa. P. vivax biology and pathogenesis are still poorly understood. The role of one highly occurring phenotype in particular where infected reticulocytes cytoadhere to noninfected normocytes, forming rosettes, remains unknown. Here, using a range of ex vivo approaches, we showed that P. vivax rosetting rates were enhanced by plasma of infected patients and that total immunoglobulin M levels correlated with rosetting frequency. Moreover, rosetting rates were also correlated with parasitemia, IL-6 and IL-10 levels in infected patients. Transcriptomic analysis of peripheral leukocytes from P. vivax-infected patients with low or moderated rosetting rates identified differentially expressed genes related to human host phagocytosis pathway. In addition, phagocytosis assay showed that rosetting parasites were less phagocyted. Collectively, these results showed that rosette formation plays a role in host immune response by hampering leukocyte phagocytosis. Thus, these findings suggest that rosetting could be an effective P. vivax immune evasion strategy.
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Affiliation(s)
- Letusa Albrecht
- Laboratório de Pesquisa em Apicomplexa, Instituto Carlos Chagas, Fiocruz Paraná, Curitiba, PR, Brazil. .,Laboratório de Doenças Tropicais Prof. Luiz Jacintho da Silva, Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.
| | - Stefanie C P Lopes
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Gerência de Malária, Manaus, AM, Brazil.,Instituto Leônidas & Maria Deane, Fiocruz Amazônia, Manaus, AM, Brazil
| | | | - Vanessa Barbosa
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Gerência de Malária, Manaus, AM, Brazil.,Instituto Leônidas & Maria Deane, Fiocruz Amazônia, Manaus, AM, Brazil
| | - Rodrigo P Almeida
- Laboratório de Pesquisa em Apicomplexa, Instituto Carlos Chagas, Fiocruz Paraná, Curitiba, PR, Brazil
| | - André M Siqueira
- Instituto Nacional de Infectologia Evandro Chagas, Fiocruz, Rio de Janeiro, RJ, Brazil
| | - Juliana Almeida Leite
- Laboratório de Doenças Tropicais Prof. Luiz Jacintho da Silva, Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil
| | - Najara C Bittencourt
- Laboratório de Doenças Tropicais Prof. Luiz Jacintho da Silva, Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil
| | | | - Catarina Bourgard
- Laboratório de Doenças Tropicais Prof. Luiz Jacintho da Silva, Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil
| | | | - Ana Carolina A V Kayano
- Laboratório de Pesquisa em Apicomplexa, Instituto Carlos Chagas, Fiocruz Paraná, Curitiba, PR, Brazil.,Laboratório de Doenças Tropicais Prof. Luiz Jacintho da Silva, Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil
| | - Irene S Soares
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of Sao Paulo, São Paulo, SP, Brazil
| | - Bruce Russell
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Laurent Rénia
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore, Singapore
| | - Marcus V G Lacerda
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Gerência de Malária, Manaus, AM, Brazil.,Instituto Leônidas & Maria Deane, Fiocruz Amazônia, Manaus, AM, Brazil
| | - Fabio T M Costa
- Laboratório de Doenças Tropicais Prof. Luiz Jacintho da Silva, Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.
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9
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Influence of CYP2C8, CYP3A4, and CYP3A5 Host Genotypes on Early Recurrence of Plasmodium vivax. Antimicrob Agents Chemother 2020; 64:AAC.02125-19. [PMID: 32366712 DOI: 10.1128/aac.02125-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 04/25/2020] [Indexed: 11/20/2022] Open
Abstract
Cytochrome P450 (CYP) enzymes are involved in the biotransformation of chloroquine (CQ), but the role of the different profiles of metabolism of this drug in relation to Plasmodium vivax recurrences has not been properly investigated. To investigate the influence of the CYP genotypes associated with CQ metabolism on the rates of P. vivax early recurrences, a case-control study was carried out. The cases included patients presenting with an early recurrence (CQ-recurrent individuals), defined as a recurrence during the first 28 days after initial infection and plasma concentrations of CQ plus desethylchloroquine (DCQ; the major CQ metabolite) higher than 100 ng/ml. A control group with no parasite recurrence over the follow-up (the CQ-responsive group) was also included. CQ and DCQ plasma levels were measured on day 28. CQ-metabolizing CYP (CYP2C8, CYP3A4, and CYP3A5) genotypes were determined by real-time PCR. An ex vivo study was conducted to verify the efficacy of CQ and DCQ against P. vivax isolates. The frequency of alleles associated with normal and slow metabolism was similar between the cases and the controls for the CYP2C8 (odds ratio [OR] = 1.45, 95% confidence interval [CI] = 0.51 to 4.14, P = 0.570), CYP3A4 (OR = 2.38, 95% CI = 0.92 to 6.19, P = 0.105), and CYP3A5 (OR = 4.17, 95% CI = 0.79 to 22.04, P = 1.038) genes. DCQ levels were higher than CQ levels, regardless of the genotype. Regarding the DCQ/CQ ratio, there was no difference between groups or between those patients who had a normal genotype and those patients who had a mutant genotype. DCQ and CQ showed similar efficacy ex vivo CYP genotypes had no influence on early recurrence rates. The similar efficacy of CQ and DCQ ex vivo could explain the absence of therapeutic failure, despite the presence of alleles associated with slow metabolism.
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10
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Dash M, Pande V, Sinha A. Putative circumsporozoite protein (CSP) of Plasmodium vivax is considerably distinct from the well-known CSP and plays a role in the protein ubiquitination pathway. Gene 2020; 721S:100024. [PMID: 32550551 PMCID: PMC7285988 DOI: 10.1016/j.gene.2019.100024] [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: 07/01/2019] [Revised: 10/21/2019] [Accepted: 11/07/2019] [Indexed: 11/29/2022]
Abstract
Amidst technical challenges which limit successful culture and genetic manipulation of P. vivax parasites, we used a computational approach to identify a critical target with evolutionary significance. The putative circumsporozoite protein on chromosome 13 of P. vivax (PvpuCSP)is distinct from the well-known vaccine candidate PfCSP. The aim of this study was to understand the role of PvpuCSP and its relatedness to the well-known CSP. The study revealed PvpuCSP as a membrane bound E3 ubiquitin ligase involved in ubiquitination. It has a species-specific tetra-peptide unit which is differentially repeated in various P. vivax strains. The PvpuCSP is different from CSP in terms of stage-specific expression and function. Since E3 ubiquitin ligases are known antimalarial drug targets targeting the proteasome pathway, PvpuCSP, with evolutionary connotation and a key role in orchestrating protein degradation in P. vivax, can be explored as a potential drug target. PvpuCSP is predicted as E3 ubiquitin ligase, a part of ubiquitination pathway. Tetra-peptide tandem repeat at C terminal of PvpuCSP is exclusive to P. vivax. Moderately expressed during all parasitic stages in host and vector Partially disordered protein with both structured domains and two distinct IDRs A transmembrane protein with highly conserved functional domain across Apicomplexa
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Affiliation(s)
- Manoswini Dash
- Division of Epidemiology and Clinical Research, ICMR-National Institute of Malaria Research, New Delhi, India
| | - Veena Pande
- Department of Biotechnology, Bhimtal Campus, Kumaun University, Nainital, Uttarakhand, India
| | - Abhinav Sinha
- Division of Epidemiology and Clinical Research, ICMR-National Institute of Malaria Research, New Delhi, India
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11
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Nedu ME, Tertis M, Cristea C, Georgescu AV. Comparative Study Regarding the Properties of Methylene Blue and Proflavine and Their Optimal Concentrations for In Vitro and In Vivo Applications. Diagnostics (Basel) 2020; 10:diagnostics10040223. [PMID: 32326607 PMCID: PMC7235860 DOI: 10.3390/diagnostics10040223] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/27/2020] [Accepted: 04/14/2020] [Indexed: 02/07/2023] Open
Abstract
Methylene blue and proflavine are fluorescent dyes used to stain nucleic acid from the molecular level to the tissue level. Already clinically used for sentinel node mapping, detection of neuroendocrine tumors, methemoglobinemia, septic shock, ifosfamide-induced encephalopathy, and photodynamic inactivation of RNA viruses, the antimicrobial, anti-inflammatory, and antioxidant effect of methylene blue has been demonstrated in different in vitro and in vivo studies. Proflavine was used as a disinfectant and bacteriostatic agent against many gram-positive bacteria, as well as a urinary antiseptic involved in highlighting cell nuclei. At the tissue level, the anti-inflammatory effects of methylene blue protect against pulmonary, renal, cardiac, pancreatic, ischemic-reperfusion lesions, and fevers. First used for their antiseptic and antiviral activity, respectively, methylene blue and proflavine turned out to be excellent dyes for diagnostic and treatment purposes. In vitro and in vivo studies demonstrated that both dyes are efficient as perfusion and tissue tracers and permitted to evaluate the minimal efficient concentration in different species, as well as their pharmacokinetics and toxicity. This review aims to identify the optimal concentrations of methylene blue and proflavine that can be used for in vivo experiments to highlight the vascularization of the skin in the case of a perforasome (both as a tissue tracer and in vascular mapping), as well as their effects on tissues. This review is intended to be a comparative and critical presentation of the possible applications of methylene blue (MB) and proflavine (PRO) in the surgical field, and the relevant biomedical findings from specialized literature to date are discussed as well.
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Affiliation(s)
- Maria-Eliza Nedu
- Department of Plastic Surgery, Faculty of Medicine, Iuliu Hațieganu University of Medicine and Pharmacy, 46-50 Viilor St., 400347 Cluj-Napoca, Romania; (M.-E.N.); (A.V.G.)
| | - Mihaela Tertis
- Department of Analytical Chemistry, Faculty of Pharmacy, Iuliu Hațieganu University of Medicine and Pharmacy, 4 Pasteur St., 400349 Cluj-Napoca, Romania;
| | - Cecilia Cristea
- Department of Analytical Chemistry, Faculty of Pharmacy, Iuliu Hațieganu University of Medicine and Pharmacy, 4 Pasteur St., 400349 Cluj-Napoca, Romania;
- Correspondence: ; Tel.: +40-264-597256
| | - Alexandru Valentin Georgescu
- Department of Plastic Surgery, Faculty of Medicine, Iuliu Hațieganu University of Medicine and Pharmacy, 46-50 Viilor St., 400347 Cluj-Napoca, Romania; (M.-E.N.); (A.V.G.)
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Cáceres Carrera L, Victoria C, Ramirez JL, Jackman C, Calzada JE, Torres R. Study of the epidemiological behavior of malaria in the Darien Region, Panama. 2015-2017. PLoS One 2019; 14:e0224508. [PMID: 31730618 PMCID: PMC6857920 DOI: 10.1371/journal.pone.0224508] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 10/15/2019] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Malaria is endemic in Darién and an assessment of the different factors affecting its epidemiology is crucial for the development of adequate strategies of surveillance, prevention, and disease control. The objective of this study was to determine the main characteristics of the epidemiological behavior of malaria in the Darien region. METHODS This research was comprised of a retrospective analysis to determine the incidence and malaria distribution in the Darien region from 2015 to 2017. We evaluated malaria indicators, disease distribution, incidence (by age group and sex), diagnostic methods, treatment, and control measures. In addition, we examined the cross-border migration activity and its possible contribution to the maintenance and distribution of malaria. RESULTS During the period of 2015-2017, we examined 41,141 thick blood smear samples, out of which 501 tested positive for malaria. Plasmodium vivax was responsible for 92.2% of those infections. Males comprised 62.7% of the total diagnosed cases. Meanwhile, a similar percentage, 62.7%, of the total cases were registered in economically active ages. The more frequent symptoms included fever (99.4%) and chills (97.4%), with 53.1% of cases registering between 2,000 and 6,000 parasites/μl of blood. The annual parasitic incidence (API) average was 3.0/1,000 inhabitants, while the slide positivity rate (SPR) was 1.2% and the annual blood examination rate (ABER) 22.5%. In Darién there is a constant internal and cross-border migration movement between Panama and Colombia. Malaria control measures consisted of the active and passive search of suspected cases and of the application of vector control measures. CONCLUSION This study provides an additional perspective on malaria epidemiology in Darién. Additional efforts are required to intensify malaria surveillance and to achieve an effective control, eventually moving closer to the objective of malaria elimination. At the same time, there is a need for more eco-epidemiological, entomological and migratory studies to determine how these factors contribute to the patterns of maintenance and dissemination of malaria.
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Affiliation(s)
- Lorenzo Cáceres Carrera
- Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama
- * E-mail:
| | | | - Jose L. Ramirez
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, Peoria, Illinois, United States of America
| | - Carmela Jackman
- Epidemiology Department of the Darién Region, Ministry of Health, Panama City, Panama
| | - José E. Calzada
- Direcction of Research and Technological Development, Gorgas Memorial Institute of Health Studies, Panama City, Panama
| | - Rolando Torres
- Department of Medical Entomology, Gorgas Memorial Institute of Health Studies, Panama City, Panama
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13
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Antonio-Nkondjio C, Ndo C, Njiokou F, Bigoga JD, Awono-Ambene P, Etang J, Ekobo AS, Wondji CS. Review of malaria situation in Cameroon: technical viewpoint on challenges and prospects for disease elimination. Parasit Vectors 2019; 12:501. [PMID: 31655608 PMCID: PMC6815446 DOI: 10.1186/s13071-019-3753-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 10/18/2019] [Indexed: 11/30/2022] Open
Abstract
Malaria still has a devastating impact on public health and welfare in Cameroon. Despite the increasing number of studies conducted on disease prevalence, transmission patterns or treatment, there are to date, not enough studies summarising findings from previous works in order to identify gaps in knowledge and areas of interest where further evidence is needed to drive malaria elimination efforts. The present study seeks to address these gaps by providing a review of studies conducted so far on malaria in Cameroon since the 1940s to date. Over 250 scientific publications were consulted for this purpose. Although there has been increased scale-up of vector control interventions which significantly reduced the morbidity and mortality to malaria across the country from a prevalence of 41% of the population reporting at least one malaria case episode in 2000 to a prevalence of 24% in 2017, the situation is not yet under control. There is a high variability in disease endemicity between epidemiological settings with prevalence of Plasmodium parasitaemia varying from 7 to 85% in children aged 6 months to 15 years after long-lasting insecticidal nets (LLINs) scale-up. Four species of Plasmodium have been recorded across the country: Plasmodium falciparum, P. malariae, P. ovale and P. vivax. Several primate-infecting Plasmodium spp. are also circulating in Cameroon. A decline of artemisinin-based combinations therapeutic efficacy from 97% in 2006 to 90% in 2016 have been reported. Several mutations in the P. falciparum chloroquine resistance (Pfcrt) and P. falciparum multidrug resistance 1 (Pfmdr1) genes conferring resistance to either 4-amino-quinoleine, mefloquine, halofanthrine and quinine have been documented. Mutations in the Pfdhfr and Pfdhps genes involved in sulfadoxine-pyrimethamine are also on the rise. No mutation associated with artemisinin resistance has been recorded. Sixteen anopheline species contribute to malaria parasite transmission with six recognized as major vectors: An. gambiae, An. coluzzii, An. arabiensis, An. funestus, An. nili and An. moucheti. Studies conducted so far, indicated rapid expansion of DDT, pyrethroid and carbamate resistance in An. gambiae, An. coluzzii, An. arabiensis and An. funestus threatening the performance of LLINs. This review highlights the complex situation of malaria in Cameroon and the need to urgently implement and reinforce integrated control strategies in different epidemiological settings, as part of the substantial efforts to consolidate gains and advance towards malaria elimination in the country.
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Affiliation(s)
- Christophe Antonio-Nkondjio
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), B. P.288 Yaoundé, Cameroun
- Centre for Research in Infectious Disease (CRID), P.O. Box 13591, Yaoundé, Cameroon
- Vector Biology Liverpool School of Tropical medicine Pembroke Place, Liverpool, UK
| | - Cyrille Ndo
- Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, P.O. Box 24157, Douala, Cameroon
- Centre for Research in Infectious Disease (CRID), P.O. Box 13591, Yaoundé, Cameroon
| | - Flobert Njiokou
- Centre for Research in Infectious Disease (CRID), P.O. Box 13591, Yaoundé, Cameroon
- Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - Jude D. Bigoga
- Laboratory for Vector Biology and control, National Reference Unit for Vector Control, The Biotechnology Center, Nkolbisson-University of Yaounde I, P.O. Box 3851, Messa, Yaounde, Cameroon
- Department of Biochemistry, Faculty of Science, University of Yaounde I, Yaounde, Cameroon
| | - Parfait Awono-Ambene
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), B. P.288 Yaoundé, Cameroun
| | - Josiane Etang
- Laboratoire de Recherche sur le Paludisme, Organisation de Coordination pour la lutte contre les Endémies en Afrique Centrale (OCEAC), B. P.288 Yaoundé, Cameroun
- Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, P.O. Box 24157, Douala, Cameroon
- Institute for Insect Biotechnology, Justus Liebig University Gießen, Winchester Str. 2, 35394 Gießen, Germany
| | - Albert Same Ekobo
- Faculty of Sciences, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - Charles S. Wondji
- Centre for Research in Infectious Disease (CRID), P.O. Box 13591, Yaoundé, Cameroon
- Vector Biology Liverpool School of Tropical medicine Pembroke Place, Liverpool, UK
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14
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Feachem RGA, Chen I, Akbari O, Bertozzi-Villa A, Bhatt S, Binka F, Boni MF, Buckee C, Dieleman J, Dondorp A, Eapen A, Sekhri Feachem N, Filler S, Gething P, Gosling R, Haakenstad A, Harvard K, Hatefi A, Jamison D, Jones KE, Karema C, Kamwi RN, Lal A, Larson E, Lees M, Lobo NF, Micah AE, Moonen B, Newby G, Ning X, Pate M, Quiñones M, Roh M, Rolfe B, Shanks D, Singh B, Staley K, Tulloch J, Wegbreit J, Woo HJ, Mpanju-Shumbusho W. Malaria eradication within a generation: ambitious, achievable, and necessary. Lancet 2019; 394:1056-1112. [PMID: 31511196 DOI: 10.1016/s0140-6736(19)31139-0] [Citation(s) in RCA: 187] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/26/2019] [Accepted: 05/07/2019] [Indexed: 01/04/2023]
Affiliation(s)
- Richard G A Feachem
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Ingrid Chen
- Global Health Group, University of California San Francisco, San Francisco, CA, USA.
| | - Omar Akbari
- Division of Biological Sciences, University of California San Diego, La Jolla, CA, USA
| | - Amelia Bertozzi-Villa
- Malaria Atlas Project, University of Oxford, Oxford, UK; Institute for Disease Modeling, Bellevue, WA, USA
| | - Samir Bhatt
- Malaria Atlas Project, University of Oxford, Oxford, UK
| | - Fred Binka
- School of Public Health, University of Health and Allied Sciences, Ho, Ghana
| | - Maciej F Boni
- Center for Infectious Disease Dynamics, Department of Biology, Penn State, University Park, PA, USA
| | - Caroline Buckee
- Department of Epidemiology, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Joseph Dieleman
- Institute for Health Metrics, University of Washington, Seattle, WA, USA
| | - Arjen Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
| | - Alex Eapen
- National Institute of Malaria Research, Chennai, India
| | - Neelam Sekhri Feachem
- Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Scott Filler
- The Global Fund to Fight AIDS, Tuberculosis and Malaria, Geneva, Switzerland
| | - Peter Gething
- Malaria Atlas Project, University of Oxford, Oxford, UK
| | - Roly Gosling
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Annie Haakenstad
- Institute for Health Metrics, University of Washington, Seattle, WA, USA
| | - Kelly Harvard
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Arian Hatefi
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Dean Jamison
- Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Kate E Jones
- Department of Genetics, Evolution and Environment, University College London, London, UK
| | | | | | - Altaf Lal
- Sun Pharma Industries, Mumbai, India
| | - Erika Larson
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Margaret Lees
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Neil F Lobo
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Angela E Micah
- Institute for Health Metrics, University of Washington, Seattle, WA, USA
| | - Bruno Moonen
- Bill & Melinda Gates Foundation, Seattle, WA, USA
| | - Gretchen Newby
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Xiao Ning
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, China
| | - Muhammad Pate
- Duke Global Health Institute, Duke University, Durham, NC, USA
| | - Martha Quiñones
- Department of Public Health, Universidad Nacional de Colombia, Bogota, Colombia
| | - Michelle Roh
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Ben Rolfe
- Asia Pacific Leaders Malaria Alliance, Singapore
| | | | - Balbir Singh
- Malaria Research Center, University Malaysia Sarawak, Sarawak, Malaysia
| | | | | | - Jennifer Wegbreit
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Hyun Ju Woo
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
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15
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Pham TV, Nguyen HV, Aguirre AR, Nguyen VV, A. Cleves M, Nguyen XX, Nguyen TT, Tran DT, Le HX, Hens N, Rosanas-Urgell A, D’Alessandro U, Speybroeck N, Erhart A. Plasmodium vivax morbidity after radical cure: A cohort study in Central Vietnam. PLoS Med 2019; 16:e1002784. [PMID: 31100064 PMCID: PMC6524795 DOI: 10.1371/journal.pmed.1002784] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 03/19/2019] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND In Vietnam, the importance of vivax malaria relative to falciparum during the past decade has steadily increased to 50%. This, together with the spread of multidrug-resistant Plasmodium falciparum, is a major challenge for malaria elimination. A 2-year prospective cohort study to assess P. vivax morbidity after radical cure treatment and related risk factors was conducted in Central Vietnam. METHODS AND FINDINGS The study was implemented between April 2009 and December 2011 in four neighboring villages in a remote forested area of Quang Nam province. P. vivax-infected patients were treated radically with chloroquine (CQ; 25 mg/kg over 3 days) and primaquine (PQ; 0.5 mg/kg/day for 10 days) and visited monthly (malaria symptoms and blood sampling) for up to 2 years. Time to first vivax recurrence was estimated by Kaplan-Meier survival analysis, and risk factors for first and recurrent infections were identified by Cox regression models. Among the 260 P. vivax patients (61% males [159/260]; age range 3-60) recruited, 240 completed the 10-day treatment, 223 entered the second month of follow-up, and 219 were followed for at least 12 months. Most individuals (76.78%, 171/223) had recurrent vivax infections identified by molecular methods (polymerase chain reaction [PCR]); in about half of them (55.61%, 124/223), infection was detected by microscopy, and 84 individuals (37.67%) had symptomatic recurrences. Median time to first recurrence by PCR was 118 days (IQR 59-208). The estimated probability of remaining free of recurrence by month 24 was 20.40% (95% CI [14.42; 27.13]) by PCR, 42.52% (95% CI [35.41; 49.44]) by microscopy, and 60.69% (95% CI [53.51; 67.11]) for symptomatic recurrences. The main risk factor for recurrence (first or recurrent) was prior P. falciparum infection. The main limitations of this study are the age of the results and the absence of a comparator arm, which does not allow estimating the proportion of vivax relapses among recurrent infections. CONCLUSION A substantial number of P. vivax recurrences, mainly submicroscopic (SM) and asymptomatic, were observed after high-dose PQ treatment (5.0 mg/kg). Prior P. falciparum infection was an important risk factor for all types of vivax recurrences. Malaria elimination efforts need to address this largely undetected P. vivax transmission by simultaneously tackling the reservoir of P. falciparum and P. vivax infections.
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Affiliation(s)
- Thanh Vinh Pham
- National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
- Research Institute of Health and Society (IRSS), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Hong Van Nguyen
- National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | - Angel Rosas Aguirre
- Research Institute of Health and Society (IRSS), Université Catholique de Louvain (UCL), Brussels, Belgium
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú
- Fund for Scientific Research (FNRS), Brussels, Belgium
| | - Van Van Nguyen
- Provincial Health Services, Tam Ky City, Quang Nam Province, Vietnam
| | - Mario A. Cleves
- Department of Pediatrics, University of Arkansas for Medical Sciences (UAMS), College of Medicine, Little Rock, Arkansas, United States of America
| | - Xa Xuan Nguyen
- National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | - Thao Thanh Nguyen
- Provincial Malaria Station, Tam Ky City, Quang Nam Province, Vietnam
| | - Duong Thanh Tran
- National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | - Hung Xuan Le
- National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | - Niel Hens
- Center for Statistics, I-BioStat, Hasselt University, Hasselt, Belgium
- Centre for health economic research and modelling infectious diseases, Vaxinfectio, University of Antwerp, Antwerp, Belgium
| | - Anna Rosanas-Urgell
- Department of Biomedical Sciences, Institute of Tropical Medicine (ITM), Antwerp, Belgium
| | - Umberto D’Alessandro
- Medical Research Council Unit The Gambia (MRCG), the London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Niko Speybroeck
- Research Institute of Health and Society (IRSS), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Annette Erhart
- Medical Research Council Unit The Gambia (MRCG), the London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Public Health, ITM, Antwerp, Belgium
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16
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Lu G, Nagbanshi M, Goldau N, Mendes Jorge M, Meissner P, Jahn A, Mockenhaupt FP, Müller O. Efficacy and safety of methylene blue in the treatment of malaria: a systematic review. BMC Med 2018; 16:59. [PMID: 29690878 PMCID: PMC5979000 DOI: 10.1186/s12916-018-1045-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/26/2018] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Methylene blue (MB) was the first synthetic antimalarial to be discovered and was used during the late 19th and early 20th centuries against all types of malaria. MB has been shown to be effective in inhibiting Plasmodium falciparum in culture, in the mouse model and in rhesus monkeys. MB was also shown to have a potent ex vivo activity against drug-resistant isolates of P. falciparum and P. vivax. In preclinical studies, MB acted synergistically with artemisinin derivates and demonstrated a strong effect on gametocyte reduction in P. falciparum. MB has, thus, been considered a potentially useful partner drug for artemisinin-based combination therapy (ACT), particularly when elimination is the final goal. The aim of this study was to review the scientific literature published until early 2017 to summarise existing knowledge on the efficacy and safety of MB in the treatment of malaria. METHODS This systematic review followed PRISMA guidelines. Studies reporting on the efficacy and safety of MB were systematically searched for in relevant electronic databases according to a pre-designed search strategy. The search (without language restrictions) was limited to studies of humans published until February 2017. RESULTS Out of 474 studies retrieved, a total of 22 articles reporting on 21 studies were eligible for analysis. The 21 included studies that reported data on 1504 malaria patients (2/3 were children). Older studies were case series and reports on MB monotherapy while recent studies were mainly controlled trials of combination regimens. MB was consistently shown to be highly effective in all endemic areas and demonstrated a strong effect on P. falciparum gametocyte reduction and synergy with ACT. MB treatment was associated with mild urogenital and gastrointestinal symptoms as well as blue coloration of urine. In G6PD-deficient African individuals, MB caused a slight but clinically non-significant haemoglobin reduction. CONCLUSIONS More studies are needed to define the effects of MB in P. falciparum malaria in areas outside Africa and against P. vivax malaria. Adding MB to ACT could be a valuable approach for the prevention of resistance development and for transmission reduction in control and elimination programs. SYSTEMATIC REVIEW REGISTRATION This study is registered at PROSPERO (registration number CRD42017062349 ).
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Affiliation(s)
- G Lu
- Medical College of Yangzhou University, Yangzhou University, Yangzhou, 225001, China.,Institute of Public Health, Medical School, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - M Nagbanshi
- Institute of Public Health, Medical School, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - N Goldau
- Institute of Public Health, Medical School, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - M Mendes Jorge
- Institute of Public Health, Medical School, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - P Meissner
- Department of Paediatric and Adolescent Medicine, Ulm University, Ulm, Germany
| | - A Jahn
- Institute of Public Health, Medical School, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - F P Mockenhaupt
- Institute of Tropical Medicine and International Health, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - O Müller
- Institute of Public Health, Medical School, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany.
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17
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D'Alessandro U, Hill J, Tarning J, Pell C, Webster J, Gutman J, Sevene E. Treatment of uncomplicated and severe malaria during pregnancy. THE LANCET. INFECTIOUS DISEASES 2018; 18:e133-e146. [PMID: 29395998 DOI: 10.1016/s1473-3099(18)30065-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 07/19/2017] [Accepted: 10/13/2017] [Indexed: 12/13/2022]
Abstract
Over the past 10 years, the available evidence on the treatment of malaria during pregnancy has increased substantially. Owing to their relative ease of use, good sensitivity and specificity, histidine rich protein 2 based rapid diagnostic tests are appropriate for symptomatic pregnant women; however, such tests are less appropriate for systematic screening because they will not detect an important proportion of infections among asymptomatic women. The effect of pregnancy on the pharmacokinetics of antimalarial drugs varies greatly between studies and class of antimalarial drugs, emphasising the need for prospective studies in pregnant and non-pregnant women. For the treatment of malaria during the first trimester, international guidelines are being reviewed by WHO. For the second and third trimester of pregnancy, results from several trials have confirmed that artemisinin-based combination treatments are safe and efficacious, although tolerability and efficacy might vary by treatment. It is now essential to translate such evidence into policies and clinical practice that benefit pregnant women in countries where malaria is endemic. Access to parasitological diagnosis or appropriate antimalarial treatment remains low in many countries and regions. Therefore, there is a pressing need for research to identify quality improvement interventions targeting pregnant women and health providers. In addition, efficient and practical systems for pharmacovigilance are needed to further expand knowledge on the safety of antimalarial drugs, particularly in the first trimester of pregnancy.
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Affiliation(s)
- Umberto D'Alessandro
- Medical Research Council Unit, Banjul, The Gambia; London School of Hygiene & Tropical Medicine, London, UK.
| | - Jenny Hill
- Liverpool School of Tropical Medicine, Liverpool, UK
| | - Joel Tarning
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Christopher Pell
- Centre for Social Science and Global Health, University of Amsterdam, Amsterdam, Netherlands; Amsterdam Institute for Global Health and Development, Amsterdam, Netherlands
| | - Jayne Webster
- London School of Hygiene & Tropical Medicine, London, UK
| | - Julie Gutman
- Malaria Branch, US Centers for Diseases Control and Prevention, Atlanta, GA, USA
| | - Esperanca Sevene
- Manhiça Health Research Center (CISM), Manhiça, Mozambique; Faculty of Medicine, Eduardo Mondlane University, Maputo, Mozambique
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18
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Genomic Analyses Reveal the Common Occurrence and Complexity of Plasmodium vivax Relapses in Cambodia. mBio 2018; 9:mBio.01888-17. [PMID: 29362233 PMCID: PMC5784252 DOI: 10.1128/mbio.01888-17] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Plasmodium vivax parasites have a unique dormant stage that can cause relapses weeks or months after the initial infection. These dormant parasites are among the main challenges of vivax malaria control as they constitute a reservoir that is difficult to eliminate. Since field studies are confounded by reinfections and possible recrudescence of drug-resistant parasites, most analyses of P. vivax relapses have focused on travelers returning from regions of malaria endemicity. However, it is not clear whether these individuals accurately recapitulate the relapse patterns of repeatedly infected individuals residing in areas of endemicity. Here, we present analyses of vivax malaria patients enrolled in a tightly controlled field study in Cambodia. After antimalarial drug treatment was administered, we relocated 20 individuals to a nontransmission area and followed them for 60 days, with blood collection performed every second day. Our analyses reveal that 60% of the patients relapsed during the monitoring period. Using whole-genome sequencing and high-throughput genotyping, we showed that relapses in Cambodia are often polyclonal and that the relapsing parasites harbor various degrees of relatedness to the parasites present in the initial infection. Our analyses also showed that clone populations differed dynamically, with new clones emerging during the course of the relapsing infections. Overall, our study data show that it is possible to investigate the patterns, dynamics, and diversity of P. vivax relapses of individuals living in a region of malaria endemicity and reveal that P. vivax relapses are much more pervasive and complex than previously considered. (This study has been registered at ClinicalTrials.gov under registration no. NCT02118090)IMPORTANCEP. vivax parasites can remain dormant in the liver and relapse weeks or months after the initial infection, greatly complicating malaria control and elimination efforts. The few investigations of this dormant stage have relied on travelers and military personnel returning from areas of malaria endemicity. However, it is not clear whether these individuals, exposed to a limited number of infections, accurately represent the patterns of relapses of individuals living in areas of endemicity, who are repeatedly infected by P. vivax parasites. Our study combined tightly controlled fieldwork with comprehensive genomic analyses, and our report provides a first opportunity to investigate the patterns, dynamics, and diversity of P. vivax relapses directly with individuals living in areas of endemicity.
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19
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Baird JK, Battle KE, Howes RE. Primaquine ineligibility in anti-relapse therapy of Plasmodium vivax malaria: the problem of G6PD deficiency and cytochrome P-450 2D6 polymorphisms. Malar J 2018; 17:42. [PMID: 29357870 PMCID: PMC5778616 DOI: 10.1186/s12936-018-2190-z] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 01/15/2018] [Indexed: 12/24/2022] Open
Abstract
The hypnozoite reservoir of Plasmodium vivax represents both the greatest obstacle and opportunity for ultimately eradicating this species. It is silent and cannot be diagnosed until it awakens and provokes a clinical attack with attendant morbidity, risk of mortality, and opportunities for onward transmission. The only licensed drug that kills hypnozoites is primaquine, which attacks the hypnozoite reservoir but imposes serious obstacles in doing so—at hypnozoitocidal doses, it invariably causes a threatening acute haemolytic anaemia in patients having an inborn deficiency in glucose-6-phosphate dehydrogenase (G6PD), affecting about 8% of people living in malaria endemic nations. That problem excludes a large number of people from safe and effective treatment of the latent stage of vivax malaria: the G6PD deficient, pregnant or lactating women, and young infants. These groups were estimated to comprise 14.3% of populations resident in the 95 countries with endemic vivax malaria. Another important obstacle regarding primaquine in the business of killing hypnozoites is its apparent metabolism to an active metabolite exclusively via cytochrome P-450 isozyme 2D6 (CYP2D6). Natural polymorphisms of this allele create genotypes expressing impaired enzymes that occur in over 20% of people living in Southeast Asia, where more than half of P. vivax infections occur globally. Taken together, the estimated frequencies of these primaquine ineligibles due to G6PD toxicity or impaired CYP2D6 activity composed over 35% of the populations at risk of vivax malaria. Much more detailed work is needed to refine these estimates, derive probabilities of error for them, and improve their ethnographic granularity in order to inform control and elimination strategy and tactics.
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Affiliation(s)
- J Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Jalan Diponegoro No.69, Central Jakarta, 10430, Indonesia.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Old Road Campus, Oxford, OX3 7FZ, UK
| | - Katherine E Battle
- Oxford Big Data Institute, Nuffield Department of Medicine, University of Oxford, Old Road Campus, Oxford, OX3 7FZ, UK
| | - Rosalind E Howes
- Oxford Big Data Institute, Nuffield Department of Medicine, University of Oxford, Old Road Campus, Oxford, OX3 7FZ, UK. .,Center for Global Health and Diseases, Case Western Reserve University, Biomedical Research Building, 2109 Adelbert Road, Cleveland, OH, 44106-4983, USA.
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20
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Mac Donald-Ottevanger MS, Adhin MR, Jitan JK, Bretas G, Vreden SG. Primaquine double dose for 7 days is inferior to single-dose treatment for 14 days in preventing Plasmodium vivax recurrent episodes in Suriname. Infect Drug Resist 2018; 11:3-8. [PMID: 29317838 PMCID: PMC5743107 DOI: 10.2147/idr.s135897] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Recurrent episodes of Plasmodium vivax are caused by dormant liver stages of the parasite, which are not eradicated by choloroquine. Therefore, effective treatment also includes the use of primaquine (PQ). However, this secondary preventive therapy is often not effective, mostly due to poor adherence to the relatively long treatment course, justifying a comparative study of the efficacy of different durations of PQ treatment. Materials and methods We included patients presenting with an acute and documented P. vivax infection from January 2006 to February 2008. All patients received chloroquine 25 mg/kg over a 3-day period. Subsequently, patients in group 7D received PQ 30 mg/day for 7 days, and patients in group 14D received standard PQ 15 mg/day for 14 days. All doses were given under supervision and patients were followed up for at least 6 months. The Kaplan–Meier method was used to estimate cumulative probability of recurrence up to 12 months after treatment initiation stratified by treatment group. Cox regression was used to assess possible determinants for recurrent parasitemia. Results Forty-seven of the 79 included patients (59.5%) were allocated to group 7D and 32 patients (40.5%) were allocated to group 14D. Recurrent parasitemia was detected in 31.9% of the cases in group 7D compared to 12.5% of the cases in group 14D (hazard ratio [HR] =3.36, 95% CI 1.11–10.16). Cumulative probability for recurrent parasitemia at 3, 6, and 12 months was 0.201 (95% CI 0.106–0.362), 0.312 (95% CI 0.190–0.485), and 0.424 (95% CI 0.274–0.615) for group 7D and 0.100 (95% CI 0.033–0.279), 0.100 (95% CI 0.033–0.279), and 0.138 (95% CI 0.054–0.327) for group 14D, respectively. When adjusted for possible confounders, differences in recurrent parasitemia remained significant between the two regimens in Cox regression analysis. Conclusion More than 30% of the patients receiving shorter treatment course had recurrent parasitemia, suggesting that the standard dose of 15 mg/day PQ for 14 days is more efficacious than 30 mg for 7 days in preventing P. vivax recurrent episodes. Furthermore, we suggest that P. vivax treatment in Suriname should be changed to PQ 30 mg/day for 14 days, as per Center for Disease Control and Prevention recommendation, in light of a recurrence rate of over 10%, even in group 14D.
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Affiliation(s)
| | - Malti R Adhin
- Department of Biochemistry, Anton de Kom University of Suriname
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21
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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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22
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Point-of-Care Testing for G6PD Deficiency: Opportunities for Screening. Int J Neonatal Screen 2018; 4:34. [PMID: 31709308 PMCID: PMC6832607 DOI: 10.3390/ijns4040034] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 11/14/2018] [Indexed: 12/15/2022] Open
Abstract
Glucose-6-phosphate dehydrogenase (G6PD) deficiency, an X-linked genetic disorder, is associated with increased risk of jaundice and kernicterus at birth. G6PD deficiency can manifest later in life as severe hemolysis, when the individual is exposed to oxidative agents that range from foods such as fava beans, to diseases such as typhoid, to medications such as dapsone, to the curative drugs for Plasmodium (P.) vivax malaria, primaquine and tafenoquine. While routine testing at birth for G6PD deficiency is recommended by the World Health Organization for populations with greater than 5% prevalence of G6PD deficiency and to inform P. vivax case management using primaquine, testing coverage is extremely low. Test coverage is low due to the need to prioritize newborn interventions and the complexity of currently available G6PD tests, especially those used to inform malaria case management. More affordable, accurate, point-of-care (POC) tests for G6PD deficiency are emerging that create an opportunity to extend testing to populations that do not have access to high throughput screening services. Some of these tests are quantitative, which provides an opportunity to address the gender disparity created by the currently available POC qualitative tests that misclassify females with intermediate G6PD activity as normal. In populations where the epidemiology for G6PD deficiency and P. vivax overlap, screening for G6PD deficiency at birth to inform care of the newborn can also be used to inform malaria case management over their lifetime.
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23
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Koepfli C, Ome-Kaius M, Jally S, Malau E, Maripal S, Ginny J, Timinao L, Kattenberg JH, Obadia T, White M, Rarau P, Senn N, Barry AE, Kazura JW, Mueller I, Robinson LJ. Sustained Malaria Control Over an 8-Year Period in Papua New Guinea: The Challenge of Low-Density Asymptomatic Plasmodium Infections. J Infect Dis 2017; 216:1434-1443. [PMID: 29029179 PMCID: PMC5853328 DOI: 10.1093/infdis/jix507] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 09/19/2017] [Indexed: 12/31/2022] Open
Abstract
Background The scale-up of effective malaria control in the last decade has resulted in a substantial decline in the incidence of clinical malaria in many countries. The effects on the proportions of asymptomatic and submicroscopic infections and on transmission potential are yet poorly understood. Methods In Papua New Guinea, vector control has been intensified since 2008, and improved diagnosis and treatment was introduced in 2012. Cross-sectional surveys were conducted in Madang Province in 2006 (with 1280 survey participants), 2010 (with 2117 participants), and 2014 (with 2516 participants). Infections were quantified by highly sensitive quantitative polymerase chain reaction (PCR) analysis, and gametocytes were quantified by reverse-transcription qPCR analysis. Results Plasmodium falciparum prevalence determined by qPCR decreased from 42% in 2006 to 9% in 2014. The P. vivax prevalence decreased from 42% in 2006 to 13% in 2010 but then increased to 20% in 2014. Parasite densities decreased 5-fold from 2006 to 2010; 72% of P. falciparum and 87% of P. vivax infections were submicroscopic in 2014. Gametocyte density and positivity correlated closely with parasitemia, and population gametocyte prevalence decreased 3-fold for P. falciparum and 29% for P. vivax from 2010 to 2014. Conclusions Sustained control has resulted in reduced malaria transmission potential, but an increasing proportion of gametocyte carriers are asymptomatic and submicroscopic and represent a challenge to malaria control.
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Affiliation(s)
- Cristian Koepfli
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- University of California–Irvine
| | - Maria Ome-Kaius
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- Papua New Guinea Institute of Medical Research, Madang
| | | | - Elisheba Malau
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | | | - Jason Ginny
- Papua New Guinea Institute of Medical Research, Madang
| | | | - Johanna Helena Kattenberg
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Papua New Guinea Institute of Medical Research, Madang
| | - Thomas Obadia
- Malaria: Parasites & Hosts Unit, Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
- Bioinformatics and Biostatistics Hub, Center for Bioinformatics, Biostatistics, and Integrative Biology, Institut Pasteur, Paris, France
| | - Michael White
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, United Kingdom
| | - Patricia Rarau
- School of Population and Global Health, University of Melbourne, Parkville, Australia
- Papua New Guinea Institute of Medical Research, Madang
| | - Nicolas Senn
- Papua New Guinea Institute of Medical Research, Madang
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Alyssa E Barry
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | | | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- Malaria: Parasites & Hosts Unit, Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
- Barcelona Center for International Health, Barcelona, Spain
| | - Leanne J Robinson
- Population Health and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- Burnet Institute, Melbourne, Australia
- Papua New Guinea Institute of Medical Research, Madang
- Correspondence: L. Robinson, PhD, MPH, Walter and Eliza Hall Institute, 1G Royal Parade, Parkville VIC 3052, Australia ()
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24
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Affiliation(s)
| | - Giovanni Benelli
- b Department of Agriculture, Food and Environment , University of Pisa , Pisa , Italy.,c The BioRobotics Institute, Scuola Superiore Sant'Anna , Pisa , Italy
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25
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Abstract
Plasmodium vivax is the second most prevalent cause of malaria worldwide and the leading cause of malaria outside of Africa. Although infections are seldom fatal clinical disease can be debilitating and imposes significant health and economic impacts on affected populations. Estimates of transmission and prevalence intensity can be problematic because many episodes of vivax originate from hypnozoite stages in the liver that have remained dormant from previous infections by an unknown mechanism. Lack of treatment options to clear hypnozoites and the ability to infect mosquitoes before disease symptoms present represent major challenges for control and eradication of vivax malaria. Compounding these challenges is the unique biology of P. vivax and limited progress in development of experimental research tools, thereby hindering development of new drugs and vaccines. Renewed emphasis on vivax malaria research is beginning to make progress in overcoming some of these challenges.
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Affiliation(s)
- John H Adams
- Center for Global Health and Infectious Diseases, Department of Global Health, University of South Florida, Tampa, Florida 33612
| | - Ivo Mueller
- Population Health & Immunity Division, Walter & Eliza Hall Institute, Parkville, Victoria 3052, Australia
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26
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Kahn M, LaRue N, Zhu C, Pal S, Mo JS, Barrett LK, Hewitt SN, Dumais M, Hemmington S, Walker A, Joynson J, Leader BT, Van Voorhis WC, Domingo GJ. Recombinant human G6PD for quality control and quality assurance of novel point-of-care diagnostics for G6PD deficiency. PLoS One 2017; 12:e0177885. [PMID: 28552983 PMCID: PMC5446111 DOI: 10.1371/journal.pone.0177885] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 05/04/2017] [Indexed: 11/19/2022] Open
Abstract
Background A large gap for the support of point-of-care testing is the availability of reagents to support quality control (QC) of diagnostic assays along the supply chain from the manufacturer to the end user. While reagents and systems exist to support QC of laboratory screening tests for glucose-6-phosphate dehydrogenase (G6PD) deficiency, they are not configured appropriately to support point-of-care testing. The feasibility of using lyophilized recombinant human G6PD as a QC reagent in novel point-of-care tests for G6PD deficiency is demonstrated. Methods Human recombinant G6PD (r-G6PD) was expressed in Escherichia coli and purified. Aliquots were stored at -80°C. Prior to lyophilization, aliquots were thawed, and three concentrations of r-G6PD (representing normal, intermediate, and deficient clinical G6PD levels) were prepared and mixed with a protective formulation, which protects the enzyme activity against degradation from denaturation during the lyophilization process. Following lyophilization, individual single-use tubes of lyophilized r-G6PD were placed in individual packs with desiccants and stored at five temperatures for one year. An enzyme assay for G6PD activity was used to ascertain the stability of r-G6PD activity while stored at different temperatures. Results Lyophilized r-G6PD is stable and can be used as a control indicator. Results presented here show that G6PD activity is stable for at least 365 days when stored at -80°C, 4°C, 30°C, and 45°C. When stored at 55°C, enzyme activity was found to be stable only through day 28. Conclusions Lyophilized r-G6PD enzyme is stable and can be used as a control for point-of-care tests for G6PD deficiency.
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Affiliation(s)
- Maria Kahn
- PATH Diagnostics Group, Seattle, Washington, United States of America
| | - Nicole LaRue
- PATH Diagnostics Group, Seattle, Washington, United States of America
| | - Changcheng Zhu
- PATH Diagnostics Group, Seattle, Washington, United States of America
| | - Sampa Pal
- PATH Diagnostics Group, Seattle, Washington, United States of America
| | - Jack S. Mo
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, United States of America
| | - Lynn K. Barrett
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, United States of America
| | - Steve N. Hewitt
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, United States of America
| | - Mitchell Dumais
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, United States of America
| | - Sandra Hemmington
- Mologic Ltd, Bedford Technology Park, Thurleigh, Bedfordshire, United Kingdom
| | - Adrian Walker
- Mologic Ltd, Bedford Technology Park, Thurleigh, Bedfordshire, United Kingdom
| | - Jeff Joynson
- Mologic Ltd, Bedford Technology Park, Thurleigh, Bedfordshire, United Kingdom
| | - Brandon T. Leader
- PATH Diagnostics Group, Seattle, Washington, United States of America
| | - Wesley C. Van Voorhis
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, Washington, United States of America
| | - Gonzalo J. Domingo
- PATH Diagnostics Group, Seattle, Washington, United States of America
- * E-mail:
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27
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Pisciotta JM, Scholl PF, Shuman JL, Shualev V, Sullivan DJ. Quantitative characterization of hemozoin in Plasmodium berghei and vivax. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2017; 7:110-119. [PMID: 28279945 PMCID: PMC5342986 DOI: 10.1016/j.ijpddr.2017.02.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 02/01/2017] [Accepted: 02/03/2017] [Indexed: 12/21/2022]
Abstract
The incidence and global distribution of chloroquine resistant (CR) Plasmodium vivax infection has increased since emerging in 1989. The mechanism of resistance in CR P. vivax has not been defined. The resistance likely relates to the formation and disposition of hemozoin as chloroquine's primary mechanism of action involves disruption of hemozoin formation. CR P. berghei strains, like CR P. vivax strains, are confined to reticulocyte host cells and reportedly they do not accumulate appreciable intraerythrocytic hemozoin. Reports comparing hemozoin production between P. vivax strains and CR to chloroquine sensitive (CS) P. berghei are absent. Here we compare in vivo patterns of hemozoin formation and distribution in blood, spleen and liver tissue of male Swiss mice infected with CS or CR P. berghei not treated with chloroquine and CR P. berghei also treated with chloroquine. Light microscopy, laser desorption mass spectrometry and a colorimetric hemozoin assay detect trace hemozoin in the blood of CR P. berghei infected mice but significant hemozoin accumulation in liver and spleen tissue. Field emission in lens scanning electron microscopy reveals CR P. berghei hemozoin crystals are morphologically smaller but similar to those formed by CS parasites. CR P. berghei produces approximately five-fold less total hemozoin than CS strain. Lipid analysis of CS and CR P. berghei sucrose gradient purified bloodstage hemozoin indicates a similar lipid environment around the isolated hemozoin, predominately monopalmitic glycerol and monostearic glycerol. In contrast to CR and CS P. berghei, colorimetric hemozoin analysis of P. vivax strains indicates similar amounts of hemozoin are produced despite differing chloroquine sensitivities. These results suggest CR P. berghei forms significant hemozoin which accumulates in liver and spleen tissues and that the P. vivax chloroquine resistance mechanism differs from P. berghei. Chloroquine resistant Plasmodium berghei release measurable hemozoin into tissues with blood hemozoin 100 times less per parasite while total in all tissues is only 5 times less than chloroquine sensitive. Chloroquine resistant P. bergheihemozoin crystals are morphologically smaller but similar to those formed by chloroquine sensitive parasites. Chloroquine resistance in P. vivax is distinct from P. berghei even though both infect reticulocytes.
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Affiliation(s)
- John M Pisciotta
- Department of Molecular Microbiology and Immunology, Johns Hopkins University, Bloomberg School of Public Health, 615 N. Wolfe St., Baltimore, MD 21205-2179, USA
| | - Peter F Scholl
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205-2103, USA
| | - Joel L Shuman
- Virginia Bioinformatics Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| | - Vladimir Shualev
- Virginia Bioinformatics Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| | - David J Sullivan
- Department of Molecular Microbiology and Immunology, Johns Hopkins University, Bloomberg School of Public Health, 615 N. Wolfe St., Baltimore, MD 21205-2179, USA.
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28
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Baird JK, Valecha N, Duparc S, White NJ, Price RN. Diagnosis and Treatment of Plasmodium vivax Malaria. Am J Trop Med Hyg 2016; 95:35-51. [PMID: 27708191 PMCID: PMC5198890 DOI: 10.4269/ajtmh.16-0171] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 04/19/2016] [Indexed: 11/07/2022] Open
Abstract
The diagnosis and treatment of Plasmodium vivax malaria differs from that of Plasmodium falciparum malaria in fundamentally important ways. This article reviews the guiding principles, practices, and evidence underpinning the diagnosis and treatment of P. vivax malaria.
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Affiliation(s)
- J Kevin Baird
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia
| | - Neena Valecha
- National Institute for Malaria Research, New Delhi, India
| | | | - Nicholas J White
- Mahidol Oxford Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Ric N Price
- Division of Global and Tropical Health, Menzies School of Health Research-Charles Darwin University, Darwin, Australia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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29
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Abstract
G6PD is a housekeeping gene expressed in all cells. Glucose-6-phosphate dehydrogenase (G6PD) is part of the pentose phosphate pathway, and its main physiologic role is to provide NADPH. G6PD deficiency, one of the commonest inherited enzyme abnormalities in humans, arises through one of many possible mutations, most of which reduce the stability of the enzyme and its level as red cells age. G6PD-deficient persons are mostly asymptomatic, but they can develop severe jaundice during the neonatal period and acute hemolytic anemia when they ingest fava beans or when they are exposed to certain infections or drugs. G6PD deficiency is a global health issue.
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Affiliation(s)
- Lucio Luzzatto
- Scientific Direction, Istituto Toscano Tumori, Viale Pieraccini 6, Florence 50139, Italy; University of Florence, Florence, Italy.
| | - Caterina Nannelli
- Core Research Laboratory-Istituto Toscano Tumori, Azienda Universitaria-Ospedaliera Careggi, Viale Pieraccini 6, Florence 50139, Italy
| | - Rosario Notaro
- Core Research Laboratory-Istituto Toscano Tumori, Azienda Universitaria-Ospedaliera Careggi, Viale Pieraccini 6, Florence 50139, Italy
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30
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Tham WH, Beeson JG, Rayner JC. Plasmodium vivax vaccine research - we've only just begun. Int J Parasitol 2016; 47:111-118. [PMID: 27899329 DOI: 10.1016/j.ijpara.2016.09.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 09/24/2016] [Accepted: 09/29/2016] [Indexed: 10/25/2022]
Abstract
Plasmodium vivax parasites cause the majority of malaria cases outside Africa, and are increasingly being acknowledged as a cause of severe disease. The unique attributes of P. vivax biology, particularly the capacity of the dormant liver stage, the hypnozoite, to maintain blood-stage infections even in the absence of active transmission, make blood-stage vaccines particularly attractive for this species. However, P. vivax vaccine development remains resolutely in first gear, with only a single blood-stage candidate having been evaluated in any depth. Experience with Plasmodium falciparum suggests that a much broader search for new candidates and a deeper understanding of high priority targets will be required to make significant advances. This review discusses some of the particular challenges of P. vivax blood-stage vaccine development, highlighting both recent advances and key remaining barriers to overcome in order to move development forward.
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Affiliation(s)
- Wai-Hong Tham
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria 3052, Australia
| | - James G Beeson
- Macfarlane Burnet Institute of Medical Research, 85 Commercial Road, Melbourne, Victoria 3004, Australia; Central Clinical School and Department of Microbiology, Monash University, Victoria, Australia
| | - Julian C Rayner
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SA, United Kingdom.
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31
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Siqueira AM, Alencar AC, Melo GC, Magalhaes BL, Machado K, Alencar Filho AC, Kuehn A, Marques MM, Manso MC, Felger I, Vieira JLF, Lameyre V, Daniel-Ribeiro CT, Lacerda MVG. Fixed-Dose Artesunate-Amodiaquine Combination vs Chloroquine for Treatment of Uncomplicated Blood Stage P. vivax Infection in the Brazilian Amazon: An Open-Label Randomized, Controlled Trial. Clin Infect Dis 2016; 64:166-174. [PMID: 27988484 PMCID: PMC5215218 DOI: 10.1093/cid/ciw706] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 10/18/2016] [Indexed: 01/31/2023] Open
Abstract
In the Brazilian Amazon, the artesunate–amodiaquine combination was more effective in preventing Plasmodium vivax recurrence. With a favorable safety profile, this antimalarial treatment proved to be a good first-line alternative. Chloroquine resistance is probably underestimated in the area. Background. Despite increasing evidence of the development of Plasmodium vivax chloroquine (CQ) resistance, there have been no trials comparing its efficacy with that of artemisinin-based combination therapies (ACTs) in Latin America. Methods. This randomized controlled trial compared the antischizontocidal efficacy and safety of a 3-day supervised treatment of the fixed-dose combination artesunate-amodiaquine Winthrop® (ASAQ) versus CQ for treatment of uncomplicated P. vivax infection in Manaus, Brazil. Patients were followed for 42 days. Primary endpoints were adequate clinical and parasitological responses (ACPR) rates at day 28. Genotype-adjustment was performed. Results. From 2012 to 2013, 380 patients were enrolled. In the per-protocol (PP) analysis, adjusted-ACPR was achieved in 100% (165/165) and 93.6% (161/172) of patients in the ASAQ and CQ arm (difference 6.4%, 95% CI 2.7%; 10.1%) at day 28 and in 97.4% (151/155) and 77.7% (129/166), respectively (difference 19.7%, 95% CI 12.9%; 26.5%), at day 42. Apart from ITT D28 assessment, superiority of ASAQ on ACPR was demonstrated. ASAQ presented faster clearance of parasitaemia and fever. Based on CQ blood level measurements, CQ resistance prevalence was estimated at 11.5% (95% CI: 7.5-17.3) up to day 42. At least one emergent adverse event (AE) was recorded for 79/190 (41x6%) in the ASAQ group and for 85/190 (44x7%) in the CQ group. Both treatments had similar safety profiles. Conclusions. ASAQ exhibited high efficacy against CQ resistant P. vivax and is an adequate alternative in the study area. Studies with an efficacious comparator, longer follow-up and genotype-adjustment can improve CQR characterization. Clinical Trials Registration. NCT01378286.
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Affiliation(s)
- Andre M Siqueira
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, .,Universidade do Estado do Amazonas, Manaus.,Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro
| | - Aline C Alencar
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado.,Universidade do Estado do Amazonas, Manaus
| | - Gisely C Melo
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado.,Universidade do Estado do Amazonas, Manaus
| | - Belisa L Magalhaes
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado.,Universidade do Estado do Amazonas, Manaus
| | - Kim Machado
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado
| | | | - Andrea Kuehn
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado.,ISGlobal, Barcelona Center for International Health Research (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | | | | | - Ingrid Felger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | | | | | | | - Marcus V G Lacerda
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado.,Universidade do Estado do Amazonas, Manaus.,Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz, Manaus, Brazil
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32
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Abstract
Introduction: Relapses are important contributors to illness and morbidity in Plasmodium vivax and P. ovale infections. Relapse prevention (radical cure) with primaquine is required for optimal management, control and ultimately elimination of Plasmodium vivax malaria. A review was conducted with publications in English, French, Portuguese and Spanish using the search terms ‘P. vivax’ and ‘relapse’. Areas covered: Hypnozoites causing relapses may be activated weeks or months after initial infection. Incidence and temporal patterns of relapse varies geographically. Relapses derive from parasites either genetically similar or different from the primary infection indicating that some derive from previous infections. Malaria illness itself may activate relapse. Primaquine is the only widely available treatment for radical cure. However, it is often not given because of uncertainty over the risks of primaquine induced haemolysis when G6PD deficiency testing is unavailable. Recommended dosing of primaquine for radical cure in East Asia and Oceania is 0.5 mg base/kg/day and elsewhere is 0.25 mg base/kg/day. Alternative treatments are under investigation. Expert commentary: Geographic heterogeneity in relapse patterns and chloroquine susceptibility of P. vivax, and G6PD deficiency epidemiology mean that radical treatment should be given much more than it is today. G6PD testing should be made widely available so primaquine can be given more safely.
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Affiliation(s)
- Cindy S Chu
- a Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine , Mahidol University , Mae Sot , Thailand.,b Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine , Mahidol University , Bangkok , Thailand
| | - Nicholas J White
- b Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine , Mahidol University , Bangkok , Thailand.,c Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine , University of Oxford , Oxford , UK
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França CT, Hostetler JB, Sharma S, White MT, Lin E, Kiniboro B, Waltmann A, Darcy AW, Li Wai Suen CSN, Siba P, King CL, Rayner JC, Fairhurst RM, Mueller I. An Antibody Screen of a Plasmodium vivax Antigen Library Identifies Novel Merozoite Proteins Associated with Clinical Protection. PLoS Negl Trop Dis 2016; 10:e0004639. [PMID: 27182597 PMCID: PMC4868274 DOI: 10.1371/journal.pntd.0004639] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 03/29/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Elimination of Plasmodium vivax malaria would be greatly facilitated by the development of an effective vaccine. A comprehensive and systematic characterization of antibodies to P. vivax antigens in exposed populations is useful in guiding rational vaccine design. METHODOLOGY/PRINCIPAL FINDINGS In this study, we investigated antibodies to a large library of P. vivax entire ectodomain merozoite proteins in 2 Asia-Pacific populations, analysing the relationship of antibody levels with markers of current and cumulative malaria exposure, and socioeconomic and clinical indicators. 29 antigenic targets of natural immunity were identified. Of these, 12 highly-immunogenic proteins were strongly associated with age and thus cumulative lifetime exposure in Solomon Islanders (P<0.001-0.027). A subset of 6 proteins, selected on the basis of immunogenicity and expression levels, were used to examine antibody levels in plasma samples from a population of young Papua New Guinean children with well-characterized individual differences in exposure. This analysis identified a strong association between reduced risk of clinical disease and antibody levels to P12, P41, and a novel hypothetical protein that has not previously been studied, PVX_081550 (IRR 0.46-0.74; P<0.001-0.041). CONCLUSION/SIGNIFICANCE These data emphasize the benefits of an unbiased screening approach in identifying novel vaccine candidate antigens. Functional studies are now required to establish whether PVX_081550 is a key component of the naturally-acquired protective immune response, a biomarker of immune status, or both.
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Affiliation(s)
- Camila T. França
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Jessica B. Hostetler
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Sumana Sharma
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Michael T. White
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Center for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Enmoore Lin
- Vector Borne Diseases Unit, PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Benson Kiniboro
- Vector Borne Diseases Unit, PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Andreea Waltmann
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Andrew W. Darcy
- National Health Training & Research Institute, Ministry of Health, Honiara, Solomon Islands
| | - Connie S. N. Li Wai Suen
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Peter Siba
- Vector Borne Diseases Unit, PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Christopher L. King
- Center for Global Health & Diseases, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Julian C. Rayner
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
- * E-mail: (JCR); (RMF); (IM)
| | - Rick M. Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail: (JCR); (RMF); (IM)
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
- * E-mail: (JCR); (RMF); (IM)
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Vitor-Silva S, Siqueira AM, de Souza Sampaio V, Guinovart C, Reyes-Lecca RC, de Melo GC, Monteiro WM, Del Portillo HA, Alonso P, Bassat Q, Lacerda MVG. Declining malaria transmission in rural Amazon: changing epidemiology and challenges to achieve elimination. Malar J 2016; 15:266. [PMID: 27165432 PMCID: PMC4863332 DOI: 10.1186/s12936-016-1326-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/03/2016] [Indexed: 01/20/2023] Open
Abstract
Background In recent years, considerable success in reducing its incidence has been achieved in Brazil, leading to a relative increase in the proportion of cases caused by Plasmodium vivax, considered a harder-to-eliminate parasite. This study aim is to describe the transmission dynamics and associated risk factors in a rural settlement area in the Western Brazilian Amazon. Methods A prospective cohort was established in a rural settlement area for 3 years. Follow-up included continuous passive case detection and monthly active case detection for a period of 6 months. Demographic, clinical and transmission control practices data were collected. Malaria diagnosis was performed through thick blood smear. Univariable and multivariable analyses of factors associated with malaria incidence were performed using negative binomial regression models. Factors associated with recurrence of P. vivax and Plasmodium falciparum malaria within 90 days of a previous episode were analysed using univariable and multivariable Cox-Proportional Hazard models. Results Malaria prevalence decreased from 7 % at the study beginning to 0.6 % at month 24, with P. vivax predominating and P. falciparum disappearing after 1 year of follow-up. Malaria incidence was significantly higher in the dry season [IRR (95 % CI) 1.4 (1.1–1.6); p < 0.001)]. Use of ITN was associated to malaria protection in the localities [IRR (95 % CI) 0.7 (0.6–0.8); p = 0.001)]. A recurrent P. vivax episode within 90 days was observed in 29.4 % of individuals after an initial diagnosis. A previous P. vivax [IRR (95 % CI) 2.3 (1.3–4.0); p = 0.006)] or mixed P. vivax + P. falciparum [IRR (95 % CI) 2.9 (1.5–5.7); p = 0.002)] infections were significantly associated to a vivax malaria episode within 90 days of follow-up. Conclusions In an area of P. falciparum and P. vivax co-endemicity, a virtual disappearance of P. falciparum was observed with P. vivax increasing its relative contribution, with a large proportion of recurring episodes. This finding reinforces the perception of P. falciparum being more responsive to early diagnosis and treatment and ITN use and the contribution of relapsing P. vivax to maintain this species’ transmission. In areas of P. vivax endemicity, antihypnozoite treatment effectiveness assessment in different transmission intensity may be a fundamental activity for malaria control and elimination. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1326-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sheila Vitor-Silva
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil.,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil
| | - André Machado Siqueira
- Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Av. Brasil, 4365, Manguinhos, Rio de Janeiro, RJ, 21040-360, Brazil
| | - Vanderson de Souza Sampaio
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil.,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil
| | - Caterina Guinovart
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Rosselló 132, 4°, 08036, Barcelona, Spain
| | - Roberto Carlos Reyes-Lecca
- Secretaria de Vigilância em Saúde, Ministério da Saúde, Lotes 5/6 Bloco F, SAF Sul Trecho 2, Brasília, DF, 70070-600, Brazil
| | - Gisely Cardoso de Melo
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil.,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil
| | - Wuelton Marcelo Monteiro
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil.,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil
| | - Hernando A Del Portillo
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Rosselló 132, 4°, 08036, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Pedro Alonso
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Rosselló 132, 4°, 08036, Barcelona, Spain
| | - Quique Bassat
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic-Universitat de Barcelona, Rosselló 132, 4°, 08036, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Marcus Vinícius Guimarães Lacerda
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil. .,Universidade do Estado do Amazonas, Av. Pedro Teixeira, 25, Dom Pedro, Manaus, AM, 69040-000, Brazil. .,Instituto de Pesquisas Leônidas & Maria Deane, Fundação Oswaldo Cruz, Rua Terezina, 476, Adrianópolis, Manaus, AM, 69057-070, Brazil.
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Sharma VP, Dev V, Phookan S. Neglected Plasmodium vivax malaria in northeastern States of India. Indian J Med Res 2016; 141:546-55. [PMID: 26139771 PMCID: PMC4510752 DOI: 10.4103/0971-5916.159511] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND & OBJECTIVES The northeastern States of India are co-endemic for Plasmodium falciparum and P. vivax malaria. The transmission intensity is low-to-moderate resulting in intermediate to stable malaria. Malaria control prioritized P. falciparum being the predominant and life threatening infection (>70%). P. vivax malaria remained somewhat neglected. The present study provides a status report of P. vivax malaria in the northeastern States of India. METHODS Data on spatial distribution of P. vivax from seven northeastern States (Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland and Tripura) were analysed retrospectively from 2008-2013. In addition, cross-sectional malarial surveys were conducted during 1991-2012 in malaria endemic pockets across the States of Assam, Meghalaya, Mizoram and Tripura to ascertain the prevalence of P. vivax in different age groups. RESULTS Vivax malaria was encountered in all northeastern States but there existed a clear division of two malaria ecotypes supporting ≤30 and >30 per cent of total malaria cases. High proportions of P. vivax cases (60-80%) were seen in Arunachal Pradesh and Nagaland in the north with alpine environment, 42-67 per cent in Manipur, whereas in Assam it varied from 23-31 per cent with subtropical and tropical climate. Meghalaya, Tripura and Mizoram had the lowest proportion of P. vivax cases. Malaria cases were recorded in all age groups but a higher proportion of P. vivax consistently occurred among <5 yr age group compared to P. falciparum (P<0.05). P. vivax cases were recorded throughout the year with peak coinciding with rainy season although transmission intensity and duration varied. INTERPRETATION & CONCLUSIONS In northeast India, P. vivax is a neglected infection. Estimating the relapsing pattern and transmission dynamics of P. vivax in various ecological settings is an important pre-requisite for planning malaria elimination in the northeastern States.
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Affiliation(s)
| | - Vas Dev
- National Institute of Malaria Research (Field Station) (ICMR), Guwahati, Assam, India
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Gandon S. Why Be Temperate: Lessons from Bacteriophage λ. Trends Microbiol 2016; 24:356-365. [PMID: 26946976 DOI: 10.1016/j.tim.2016.02.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 02/01/2016] [Accepted: 02/09/2016] [Indexed: 01/19/2023]
Abstract
Many pathogens have evolved the ability to induce latent infections of their hosts. The bacteriophage λ is a classical model for exploring the regulation and the evolution of latency. Here, I review recent experimental studies on phage λ that identify specific conditions promoting the evolution of lysogenic life cycles. In addition, I present specific adaptations of phage λ that allow this virus to react plastically to variations in the environment and to reactivate its lytic life cycle. All of these different examples are discussed in the light of evolutionary epidemiology theory to disentangle the different evolutionary forces acting on temperate phages. Understanding phage λ adaptations yield important insights into the evolution of latency in other microbes, including several life-threatening human pathogens.
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Affiliation(s)
- Sylvain Gandon
- CEFE UMR 5175, CNRS - Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, 1919, route de Mende, 34293 Montpellier Cedex 5, France.
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37
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Targeting vivax malaria in the Asia Pacific: The Asia Pacific Malaria Elimination Network Vivax Working Group. Malar J 2015; 14:484. [PMID: 26627892 PMCID: PMC4667409 DOI: 10.1186/s12936-015-0958-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 10/21/2015] [Indexed: 11/17/2022] Open
Abstract
The Asia Pacific Malaria Elimination Network (APMEN) is a collaboration of 18 country partners committed to eliminating malaria from within their borders. Over the past 5 years, APMEN has helped to build the knowledge, tools and in-country technical expertise required to attain this goal. At its inaugural meeting in Brisbane in 2009, Plasmodium vivax infections were identified across the region as a common threat to this ambitious programme; the APMEN Vivax Working Group was established to tackle specifically this issue. The Working Group developed a four-stage strategy to identify knowledge gaps, build regional consensus on shared priorities, generate evidence and change practice to optimize malaria elimination activities. This case study describes the issues faced and the solutions found in developing this robust strategic partnership between national programmes and research partners within the Working Group. The success of the approach adopted by the group may facilitate similar applications in other regions seeking to deploy evidence-based policy and practice.
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Affiliation(s)
- The Vivax Working Group
- The APMEN Vivax Working Group, Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT 0810 Australia
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38
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Howes RE, Reiner Jr. RC, Battle KE, Longbottom J, Mappin B, Ordanovich D, Tatem AJ, Drakeley C, Gething PW, Zimmerman PA, Smith DL, Hay SI. Plasmodium vivax Transmission in Africa. PLoS Negl Trop Dis 2015; 9:e0004222. [PMID: 26587988 PMCID: PMC4654493 DOI: 10.1371/journal.pntd.0004222] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 10/19/2015] [Indexed: 12/22/2022] Open
Abstract
Malaria in sub-Saharan Africa has historically been almost exclusively attributed to Plasmodium falciparum (Pf). Current diagnostic and surveillance systems in much of sub-Saharan Africa are not designed to identify or report non-Pf human malaria infections accurately, resulting in a dearth of routine epidemiological data about their significance. The high prevalence of Duffy negativity provided a rationale for excluding the possibility of Plasmodium vivax (Pv) transmission. However, review of varied evidence sources including traveller infections, community prevalence surveys, local clinical case reports, entomological and serological studies contradicts this viewpoint. Here, these data reports are weighted in a unified framework to reflect the strength of evidence of indigenous Pv transmission in terms of diagnostic specificity, size of individual reports and corroboration between evidence sources. Direct evidence was reported from 21 of the 47 malaria-endemic countries studied, while 42 countries were attributed with infections of visiting travellers. Overall, moderate to conclusive evidence of transmission was available from 18 countries, distributed across all parts of the continent. Approximately 86.6 million Duffy positive hosts were at risk of infection in Africa in 2015. Analysis of the mechanisms sustaining Pv transmission across this continent of low frequency of susceptible hosts found that reports of Pv prevalence were consistent with transmission being potentially limited to Duffy positive populations. Finally, reports of apparent Duffy-independent transmission are discussed. While Pv is evidently not a major malaria parasite across most of sub-Saharan Africa, the evidence presented here highlights its widespread low-level endemicity. An increased awareness of Pv as a potential malaria parasite, coupled with policy shifts towards species-specific diagnostics and reporting, will allow a robust assessment of the public health significance of Pv, as well as the other neglected non-Pf parasites, which are currently invisible to most public health authorities in Africa, but which can cause severe clinical illness and require specific control interventions.
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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, United States of America
- * E-mail:
| | - Robert C. Reiner Jr.
- Department of Epidemiology and Biostatistics, School of Public Health, Indiana University, Bloomington, Indiana, United States of America
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Katherine E. Battle
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Joshua Longbottom
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Bonnie Mappin
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Dariya Ordanovich
- Department of Geography and Environment, University of Southampton, Highfield, Southampton, United Kingdom
| | - Andrew J. Tatem
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
- Department of Geography and Environment, University of Southampton, Highfield, Southampton, United Kingdom
- Flowminder Foundation, Stockholm, Sweden
| | - Chris Drakeley
- Malaria Centre, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Peter W. Gething
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Peter A. Zimmerman
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - David L. Smith
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
- Sanaria Institute for Global Health and Tropical Medicine, Rockville, Maryland, United States of America
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, United States of America
| | - Simon I. Hay
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, United States of America
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Expression of Plasmodium vivax crt-o Is Related to Parasite Stage but Not Ex Vivo Chloroquine Susceptibility. Antimicrob Agents Chemother 2015; 60:361-7. [PMID: 26525783 PMCID: PMC4704153 DOI: 10.1128/aac.02207-15] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 10/19/2015] [Indexed: 11/20/2022] Open
Abstract
Chloroquine (CQ)-resistant Plasmodium vivax is present in most countries where P. vivax infection is endemic, but the underlying molecular mechanisms responsible remain unknown. Increased expression of P. vivaxcrt-o (pvcrt-o) has been correlated with in vivo CQ resistance in an area with low-grade resistance. We assessed pvcrt-o expression in isolates from Papua (Indonesia), where P. vivax is highly CQ resistant. Ex vivo drug susceptibilities to CQ, amodiaquine, piperaquine, mefloquine, and artesunate were determined using a modified schizont maturation assay. Expression levels of pvcrt-o were measured using a novel real-time quantitative reverse transcription-PCR method. Large variations in pvcrt-o expression were observed across the 51 isolates evaluated, with the fold change in expression level ranging from 0.01 to 59 relative to that seen with the P. vivax β-tubulin gene and from 0.01 to 24 relative to that seen with the P. vivax aldolase gene. Expression was significantly higher in isolates with the majority of parasites at the ring stage of development (median fold change, 1.7) compared to those at the trophozoite stage (median fold change, 0.5; P < 0.001). Twenty-nine isolates fulfilled the criteria for ex vivo drug susceptibility testing and showed high variability in CQ responses (median, 107.9 [range, 6.5 to 345.7] nM). After controlling for the parasite stage, we found that pvcrt-o expression levels did not correlate with the ex vivo response to CQ or with that to any of the other antimalarials tested. Our results highlight the importance of development-stage composition for measuring pvcrt-o expression and suggest that pvcrt-o transcription is not a primary determinant of ex vivo drug susceptibility. A comprehensive transcriptomic approach is warranted for an in-depth investigation of the role of gene expression levels and P. vivax drug resistance.
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40
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Development of vaccines for Plasmodium vivax malaria. Vaccine 2015; 33:7489-95. [PMID: 26428453 DOI: 10.1016/j.vaccine.2015.09.060] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 09/04/2015] [Accepted: 09/15/2015] [Indexed: 12/28/2022]
Abstract
Plasmodium vivax continues to cause significant morbidity outside Africa with more than 50% of malaria cases in many parts of South and South-east Asia, Pacific islands, Central and South America being attributed to P. vivax infections. The unique biology of P. vivax, including its ability to form latent hypnozoites that emerge months to years later to cause blood stage infections, early appearance of gametocytes before clinical symptoms are apparent and a shorter development cycle in the vector makes elimination of P. vivax using standard control tools difficult. The availability of an effective vaccine that provides protection and prevents transmission would be a valuable tool in efforts to eliminate P. vivax. Here, we review the latest developments related to P. vivax malaria vaccines and discuss the challenges as well as directions toward the goal of developing highly efficacious vaccines against P. vivax malaria.
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41
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Gonçalves LA, Cravo P, Ferreira MU. Emerging Plasmodium vivax resistance to chloroquine in South America: an overview. Mem Inst Oswaldo Cruz 2015. [PMID: 25184999 PMCID: PMC4156446 DOI: 10.1590/0074-0276130579] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The global emergence of Plasmodium vivax strains resistant to
chloroquine (CQ) since the late 1980s is complicating the current international
efforts for malaria control and elimination. Furthermore, CQ-resistant vivax malaria
has already reached an alarming prevalence in Indonesia, East Timor and Papua New
Guinea. More recently, in vivo studies have documented CQ-resistant P.
vivax infections in Guyana, Peru and Brazil. Here, we summarise the
available data on CQ resistance across P. vivax-endemic areas of
Latin America by combining published in vivo and in vitro studies. We also review the
current knowledge regarding the molecular mechanisms of CQ resistance in P.
vivax and the prospects for developing and standardising reliable
molecular markers of drug resistance. Finally, we discuss how the Worldwide
Antimalarial Resistance Network, an international collaborative effort involving
malaria experts from all continents, might contribute to the current regional efforts
to map CQ-resistant vivax malaria in South America.
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Affiliation(s)
| | - Pedro Cravo
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO, Brasil
| | - Marcelo Urbano Ferreira
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
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Sturrock HJW, Roberts KW, Wegbreit J, Ohrt C, Gosling RD. Tackling imported malaria: an elimination endgame. Am J Trop Med Hyg 2015; 93:139-144. [PMID: 26013369 PMCID: PMC4497886 DOI: 10.4269/ajtmh.14-0256] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 02/01/2015] [Indexed: 12/31/2022] Open
Abstract
As countries move toward malaria elimination, imported infections become increasingly significant as they often represent the majority of cases, can sustain transmission, cause resurgences, and lead to mortality. Here we review and critique current methods to prevent malaria importation in countries pursuing elimination and explore methods applied in other transmission settings and to other diseases that could be transferred to support malaria elimination. To improve intervention targeting we need a better understanding of the characteristics of populations importing infections and their patterns of migration, improved methods to reliably classify infections as imported or acquired locally, and ensure early and accurate diagnosis. The potential for onward transmission in the most receptive and vulnerable locations can be predicted through high-resolution risk mapping that can help malaria elimination or prevention of reintroduction programs target resources. Cross border and regional initiatives can be highly effective when based on an understanding of human and parasite movement. Ultimately, determining the optimal combinations of approaches to address malaria importation will require an evaluation of their impact, cost effectiveness, and operational feasibility.
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Affiliation(s)
- Hugh J. W. Sturrock
- Malaria Elimination Initiative, Global Health Group, University of California, San Francisco, California
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Koepfli C, Rodrigues PT, Antao T, Orjuela-Sánchez P, Van den Eede P, Gamboa D, van Hong N, Bendezu J, Erhart A, Barnadas C, Ratsimbasoa A, Menard D, Severini C, Menegon M, Nour BYM, Karunaweera N, Mueller I, Ferreira MU, Felger I. Plasmodium vivax Diversity and Population Structure across Four Continents. PLoS Negl Trop Dis 2015; 9:e0003872. [PMID: 26125189 PMCID: PMC4488360 DOI: 10.1371/journal.pntd.0003872] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 06/02/2015] [Indexed: 01/12/2023] Open
Abstract
Plasmodium vivax is the geographically most widespread human malaria parasite. To analyze patterns of microsatellite diversity and population structure across countries of different transmission intensity, genotyping data from 11 microsatellite markers was either generated or compiled from 841 isolates from four continents collected in 1999–2008. Diversity was highest in South-East Asia (mean allelic richness 10.0–12.8), intermediate in the South Pacific (8.1–9.9) Madagascar and Sudan (7.9–8.4), and lowest in South America and Central Asia (5.5–7.2). A reduced panel of only 3 markers was sufficient to identify approx. 90% of all haplotypes in South Pacific, African and SE-Asian populations, but only 60–80% in Latin American populations, suggesting that typing of 2–6 markers, depending on the level of endemicity, is sufficient for epidemiological studies. Clustering analysis showed distinct clusters in Peru and Brazil, but little sub-structuring was observed within Africa, SE-Asia or the South Pacific. Isolates from Uzbekistan were exceptional, as a near-clonal parasite population was observed that was clearly separated from all other populations (FST>0.2). Outside Central Asia FST values were highest (0.11–0.16) between South American and all other populations, and lowest (0.04–0.07) between populations from South-East Asia and the South Pacific. These comparisons between P. vivax populations from four continents indicated that not only transmission intensity, but also geographical isolation affect diversity and population structure. However, the high effective population size results in slow changes of these parameters. This persistency must be taken into account when assessing the impact of control programs on the genetic structure of parasite populations. Plasmodium vivax is the predominant malaria parasite in Latin America, Asia and the South Pacific. Different factors are expected to shape diversity and population structure across continents, e.g. transmission intensity which is much lower in South America as compared to Southeast-Asia and the South Pacific, or geographical isolation of P. vivax populations in the South Pacific. We have compiled data from 841 isolates from South and Central America, Africa, Central Asia, Southeast-Asia and the South Pacific typed with a panel of 11 microsatellite markers. Diversity was highest in Southeast-Asia, where transmission is intermediate-high and migration of infected hosts is high, and lowest in South America and Central Asia where malaria transmission is low and focal. Reducing the panel of microsatellites showed that 2–6 markers are sufficient for genotyping for most drug trials and epidemiological studies, as these markers can identify >90% of all haplotypes. Parasites clustered according to continental origin, with high population differentiation between South American and Central Asian populations and the other populations, and lowest differences between Southeast-Asia and the South Pacific. Current attempts to reduce malaria transmission might change this pattern, but only after transmission is reduced for an extended period of time.
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Affiliation(s)
- Cristian Koepfli
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Walter and Eliza Hall Institute, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Priscila T. Rodrigues
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Tiago Antao
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Pamela Orjuela-Sánchez
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Peter Van den Eede
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Dionicia Gamboa
- Instituto de Medicina Tropical Alexander Von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Nguyen van Hong
- National Institute of Malariology, Parasitology, and Entomology, Hanoi, Vietnam
| | - Jorge Bendezu
- Instituto de Medicina Tropical Alexander Von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Annette Erhart
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Céline Barnadas
- Walter and Eliza Hall Institute, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Arsène Ratsimbasoa
- Immunology Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar
| | - Didier Menard
- Institut Pasteur de Cambodge, Malaria Molecular Epidemiology Unit, Phnom Penh, Cambodia
| | - Carlo Severini
- Department of Infectious, Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Michela Menegon
- Department of Infectious, Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Bakri Y. M. Nour
- Department of Parasitology, Blue Nile National Institute for Communicable Diseases, University of Gezira, Wad Medani, Sudan
| | - Nadira Karunaweera
- Department of Parasitology, Faculty of Medicine, University of Colombo, Sri Lanka
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
- Barcelona Centre for International Health Research, Barcelona, Spain
| | - Marcelo U. Ferreira
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Ingrid Felger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
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Baird JK, Dewi M, Subekti D, Elyazar I, Satyagraha AW. Noninferiority of glucose-6-phosphate dehydrogenase deficiency diagnosis by a point-of-care rapid test vs the laboratory fluorescent spot test demonstrated by copper inhibition in normal human red blood cells. Transl Res 2015; 165:677-88. [PMID: 25312015 PMCID: PMC4451869 DOI: 10.1016/j.trsl.2014.09.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 08/13/2014] [Accepted: 09/17/2014] [Indexed: 01/08/2023]
Abstract
Tens of millions of patients diagnosed with vivax malaria cannot safely receive primaquine therapy against repeated attacks caused by activation of dormant liver stages called hypnozoites. Most of these patients lack access to screening for glucose-6-phosphate dehydrogenase (G6PD) deficiency, a highly prevalent disorder causing serious acute hemolytic anemia with primaquine therapy. We optimized CuCl inhibition of G6PD in normal red blood cells (RBCs) to assess G6PD diagnostic technologies suited to point of care in the impoverished rural tropics. The most widely applied technology for G6PD screening-the fluorescent spot test (FST)-is impractical in that setting. We evaluated a new point-of-care G6PD screening kit (CareStart G6PD, CSG) against FST using graded CuCl treatments to simulate variable hemizygous states, and varying proportions of CuCl-treated RBC suspensions to simulate variable heterozygous states of G6PD deficiency. In experiments double-blinded to CuCl treatment, technicians reading FST and CSG test (n = 269) classified results as positive or negative for deficiency. At G6PD activity ≤40% of normal (n = 112), CSG test was not inferior to FST in detecting G6PD deficiency (P = 0.003), with 96% vs 90% (P = 0.19) sensitivity and 75% and 87% (P = 0.01) specificity, respectively. The CSG test costs less, requires no specialized equipment, laboratory skills, or cold chain for successful application, and performs as well as the FST standard of care for G6PD screening. Such a device may vastly expand access to primaquine therapy and aid in mitigating the very substantial burden of morbidity and mortality imposed by the hypnozoite reservoir of vivax malaria.
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Affiliation(s)
- J Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia; Nuffield Department of Medicine, Centre for Tropical Medicine, University of Oxford, Oxford, United Kingdom.
| | - Mewahyu Dewi
- Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia
| | - Decy Subekti
- Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia
| | - Iqbal Elyazar
- Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia
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Lin JW, Spaccapelo R, Schwarzer E, Sajid M, Annoura T, Deroost K, Ravelli RBG, Aime E, Capuccini B, Mommaas-Kienhuis AM, O'Toole T, Prins F, Franke-Fayard BMD, Ramesar J, Chevalley-Maurel S, Kroeze H, Koster AJ, Tanke HJ, Crisanti A, Langhorne J, Arese P, Van den Steen PE, Janse CJ, Khan SM. Replication of Plasmodium in reticulocytes can occur without hemozoin formation, resulting in chloroquine resistance. ACTA ACUST UNITED AC 2015; 212:893-903. [PMID: 25941254 PMCID: PMC4451122 DOI: 10.1084/jem.20141731] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Accepted: 04/08/2015] [Indexed: 01/03/2023]
Abstract
Lin et al. generate Plasmodium berghei mutants lacking enzymes critical to hemoglobin digestion. A double gene deletion mutant lacking enzymes involved in the initial steps of hemoglobin proteolysis is able to replicate inside reticulocytes of infected mice with limited hemoglobin degradation and no hemozoin formation, and moreover, is resistant to the antimalarial drug chloroquine. Most studies on malaria-parasite digestion of hemoglobin (Hb) have been performed using P. falciparum maintained in mature erythrocytes, in vitro. In this study, we examine Plasmodium Hb degradation in vivo in mice, using the parasite P. berghei, and show that it is possible to create mutant parasites lacking enzymes involved in the initial steps of Hb proteolysis. These mutants only complete development in reticulocytes and mature into both schizonts and gametocytes. Hb degradation is severely impaired and large amounts of undigested Hb remains in the reticulocyte cytoplasm and in vesicles in the parasite. The mutants produce little or no hemozoin (Hz), the detoxification by-product of Hb degradation. Further, they are resistant to chloroquine, an antimalarial drug that interferes with Hz formation, but their sensitivity to artesunate, also thought to be dependent on Hb degradation, is retained. Survival in reticulocytes with reduced or absent Hb digestion may imply a novel mechanism of drug resistance. These findings have implications for drug development against human-malaria parasites, such as P. vivax and P. ovale, which develop inside reticulocytes.
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Affiliation(s)
- Jing-Wen Lin
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands Division of Parasitology, MRC National Institute for Medical Research, London NW7 1AA, England, UK
| | - Roberta Spaccapelo
- Department of Experimental Medicine, University of Perugia, Piazzale Gambuli, 06132 Perugia, Italy
| | - Evelin Schwarzer
- Department of Oncology, University of Torino, 10124 Torino, Italy
| | - Mohammed Sajid
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Takeshi Annoura
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Katrien Deroost
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium
| | - Raimond B G Ravelli
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Elena Aime
- Department of Experimental Medicine, University of Perugia, Piazzale Gambuli, 06132 Perugia, Italy
| | - Barbara Capuccini
- Department of Experimental Medicine, University of Perugia, Piazzale Gambuli, 06132 Perugia, Italy Division of Parasitology, MRC National Institute for Medical Research, London NW7 1AA, England, UK
| | - Anna M Mommaas-Kienhuis
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Tom O'Toole
- Department of Molecular Cell Biology and Immunology, Vrije University Medical Center, 1007 MB Amsterdam, Netherlands
| | - Frans Prins
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Blandine M D Franke-Fayard
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Jai Ramesar
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Séverine Chevalley-Maurel
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Hans Kroeze
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Abraham J Koster
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Hans J Tanke
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Andrea Crisanti
- Department of Experimental Medicine, University of Perugia, Piazzale Gambuli, 06132 Perugia, Italy Department of Biological Sciences, Imperial College London, South Kensington Campus, SAF, London SW7 2AZ, England, UK
| | - Jean Langhorne
- Division of Parasitology, MRC National Institute for Medical Research, London NW7 1AA, England, UK
| | - Paolo Arese
- Department of Oncology, University of Torino, 10124 Torino, Italy
| | - Philippe E Van den Steen
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium
| | - Chris J Janse
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
| | - Shahid M Khan
- Leiden Malaria Research Group, Department of Parasitology, Department of Molecular Cell Biology, and Department of Pathology, Leiden University Medical Centre, 2333 ZA Leiden, Netherlands
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Baird K. Origins and implications of neglect of G6PD deficiency and primaquine toxicity in Plasmodium vivax malaria. Pathog Glob Health 2015; 109:93-106. [PMID: 25943156 PMCID: PMC4455359 DOI: 10.1179/2047773215y.0000000016] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Most of the tens of millions of clinical attacks caused by Plasmodium vivax each year likely originate from dormant liver forms called hypnozoites. We do not systematically attack that reservoir because the only drug available, primaquine, is poorly suited to doing so. Primaquine was licenced for anti-relapse therapy in 1952 and became available despite threatening patients having an inborn deficiency of glucose-6-phosphate dehydrogenase (G6PD) with acute haemolytic anaemia. The standard method for screening G6PD deficiency, the fluorescent spot test, has proved impractical where most malaria patients live. The blind administration of daily primaquine is dangerous, but so too are the relapses invited by withholding treatment. Absent G6PD screening, providers must choose between risking harm by the parasite or its treatment. How did this dilemma escape redress in science, clinical medicine and public health? This review offers critical historic reflection on the neglect of this serious problem in the chemotherapy of P. vivax.
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47
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Soares RR, da Silva JMF, Carlos BC, da Fonseca CC, de Souza LSA, Lopes FV, de Paula Dias RM, Moreira POL, Abramo C, Viana GHR, de Pila Varotti F, da Silva AD, Scopel KKG. New quinoline derivatives demonstrate a promising antimalarial activity against Plasmodium falciparum in vitro and Plasmodium berghei in vivo. Bioorg Med Chem Lett 2015; 25:2308-13. [PMID: 25920564 DOI: 10.1016/j.bmcl.2015.04.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 04/01/2015] [Accepted: 04/08/2015] [Indexed: 11/19/2022]
Abstract
Malaria continues to be an important public health problem in the world. Nowadays, the widespread parasite resistance to many drugs used in antimalarial therapy has made the effective treatment of cases and control of the disease a constant challenge. Therefore, the discovery of new molecules with good antimalarial activity and tolerance to human use can be really important in the further treatment of the disease. In this study we have investigated the antiplasmodial activity of 10 synthetic compounds derived from quinoline, five of them combined to sulfonamide and five to the hydrazine or hydrazide group. The compounds were evaluated according to their cytotoxicity against HepG2 and HeLa cell lines, their antimalarial activity against CQ-sensitive and CQ-resistant Plasmodium falciparum strains and, finally, their schizonticide blood action in mice infected with Plasmodium berghei NK65. The compounds exhibited no cytotoxic action in HepG2 and HeLa cell lines when tested up to a concentration of 100 μg/mL. In addition, the hydrazine or hydrazide derivative compounds were less cytotoxic against cell lines and more active against CQ-sensitive and CQ-resistant P. falciparum strains, showing high SI (>1000 when SI was calculated using the CC50 from the 3D7 strain as reference). When tested in vivo, the hydrazine derivative 1f compound showed activity against the development of blood parasites similar to that observed with CQ, the reference drug. Interestingly, the 1f compound demonstrated the best LipE value (4.84) among all those tested in vivo. Considering the in vitro and in vivo activities of the compounds studied here and the LipE values, we believe the 1f compound to be the most promising molecule for further studies in antimalarial chemotherapy.
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Affiliation(s)
- Roberta Reis Soares
- Departamento de Parasitologia, Microbiologia e Imunologia, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer s/n, Martelos, 36036-900 Juiz de Fora, MG, Brazil.
| | - José Marcio Fernandes da Silva
- Departamento de Parasitologia, Microbiologia e Imunologia, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer s/n, Martelos, 36036-900 Juiz de Fora, MG, Brazil.
| | - Bianca Cecheto Carlos
- Instituto de Biotecnologia (IBTEC), Universidade Estadual Paulista, Alameda dos Tecomarias, s/n, 18607-440 Botucatu, SP, Brazil.
| | - Camila Campos da Fonseca
- Departamento de Parasitologia, Microbiologia e Imunologia, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer s/n, Martelos, 36036-900 Juiz de Fora, MG, Brazil.
| | - Laila Salomé Araújo de Souza
- Departamento de Parasitologia, Microbiologia e Imunologia, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer s/n, Martelos, 36036-900 Juiz de Fora, MG, Brazil.
| | - Fernanda Valério Lopes
- Departamento de Parasitologia, Microbiologia e Imunologia, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer s/n, Martelos, 36036-900 Juiz de Fora, MG, Brazil.
| | - Rafael Mafra de Paula Dias
- Instituto de Química de São Carlos, Universidade de São Paulo. Avenida João Dagnone, n° 1100, Jardim Santa Angelina, 13563-120 São Carlos, SP, Brazil.
| | - Paulo Otávio Lourenço Moreira
- Núcleo de Pesquisa em Química Biológica (NQBio), Universidade de São João Del Rei, Rua Sebastião Gonçalves Coelho, Chanadour, 35501-296 Divinópolis, MG, Brazil.
| | - Clarice Abramo
- Departamento de Parasitologia, Microbiologia e Imunologia, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer s/n, Martelos, 36036-900 Juiz de Fora, MG, Brazil.
| | - Gustavo Henrique Ribeiro Viana
- Núcleo de Pesquisa em Química Biológica (NQBio), Universidade de São João Del Rei, Rua Sebastião Gonçalves Coelho, Chanadour, 35501-296 Divinópolis, MG, Brazil.
| | - Fernando de Pila Varotti
- Núcleo de Pesquisa em Química Biológica (NQBio), Universidade de São João Del Rei, Rua Sebastião Gonçalves Coelho, Chanadour, 35501-296 Divinópolis, MG, Brazil.
| | - Adilson David da Silva
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer s/n, Martelos, 36036-900 Juiz de Fora, MG, Brazil.
| | - Kézia Katiani Gorza Scopel
- Departamento de Parasitologia, Microbiologia e Imunologia, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer s/n, Martelos, 36036-900 Juiz de Fora, MG, Brazil; Departamento of Global Health, University of South Florida, 3720 Spectrun Blvd, suit 304, Tampa, FL 33612, USA.
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48
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Shanks GD, Edstein MD, Jacobus D. Evolution from double to triple-antimalarial drug combinations. Trans R Soc Trop Med Hyg 2014; 109:182-8. [DOI: 10.1093/trstmh/tru199] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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49
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Teixeira C, Vale N, Pérez B, Gomes A, Gomes JRB, Gomes P. "Recycling" classical drugs for malaria. Chem Rev 2014; 114:11164-220. [PMID: 25329927 DOI: 10.1021/cr500123g] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Cátia Teixeira
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal.,CICECO, Departamento de Química, Universidade de Aveiro , P-3810-193 Aveiro, Portugal
| | - Nuno Vale
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal
| | - Bianca Pérez
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal
| | - Ana Gomes
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal
| | - José R B Gomes
- CICECO, Departamento de Química, Universidade de Aveiro , P-3810-193 Aveiro, Portugal
| | - Paula Gomes
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal
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50
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Tratamiento de la malaria en adultos en países no endémicos. Med Clin (Barc) 2014; 143:216-21. [DOI: 10.1016/j.medcli.2014.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 12/17/2013] [Accepted: 01/08/2014] [Indexed: 11/23/2022]
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