1
|
Marsh K, Akl E, Achan J, Alzahrani M, Baird JK, Bousema T, Gamboa D, Lacerda M, Mendis K, Penny M, Schapira A, Sovannaroth S, Wongsrichanalai C, Tiffany A, Li X, Shutes E, Schellenberg D, Alonso P, Lindblade KA. Development of WHO Recommendations for the Final Phase of Elimination and Prevention of Re-Establishment of Malaria. Am J Trop Med Hyg 2024; 110:3-10. [PMID: 38118172 PMCID: PMC10993787 DOI: 10.4269/ajtmh.22-0768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Accepted: 06/02/2023] [Indexed: 12/22/2023] Open
Abstract
The WHO recommends that all affected countries work toward the elimination of malaria, even those still experiencing a high burden of disease. However, malaria programs in the final phase of elimination or those working to prevent re-establishment of transmission after elimination could benefit from specific evidence-based recommendations for these settings as part of comprehensive and quality-controlled malaria guidelines. The WHO convened an external guideline development group to formulate recommendations for interventions to reduce or prevent malaria transmission in areas with very low- to low-transmission levels and those that have eliminated malaria. In addition, several interventions that could be deployed in higher burden areas to accelerate elimination, such as mass drug administration, were reviewed. Systematic reviews were conducted that synthesized and evaluated evidence for the benefits and harms of public health interventions and summarized critical contextual factors from a health systems perspective. A total of 12 recommendations were developed, with five related to mass interventions that could be deployed at higher transmission levels and seven that would be most appropriate for programs in areas close to elimination or those working to prevent re-establishment of transmission. Four chemoprevention, two active case detection, and one vector control interventions were positively recommended, whereas two chemoprevention and three active case detection interventions were not recommended by the WHO. None of the recommendations were classified as strong given the limited and low-quality evidence base. Approaches to conducting higher quality research in very low- to low-transmission settings to improve the strength of WHO recommendations are discussed.
Collapse
Affiliation(s)
- Kevin Marsh
- Centre for Tropical Medicine and Global Health, University of Oxford, United Kingdom
| | - Elie Akl
- Department of Internal Medicine, American University of Beirut, Lebanon
- Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, Canada
| | - Jane Achan
- Malaria Consortium, London, United Kingdom
| | | | - J. Kevin Baird
- Centre for Tropical Medicine and Global Health, University of Oxford, United Kingdom
- Oxford University Clinical Research Unit, Faculty of Medicine Universitas Indonesia, Jakarta, Indonesia
| | - Teun Bousema
- Department of Medical Microbiology, Radboud University Medical Center, Radboud, the Netherlands
| | - Dionicia Gamboa
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Marcus Lacerda
- Tropical Medicine Foundation Dr Heitor Vieira Dourado, Manaus, Brazil
| | - Kamini Mendis
- Department of Parasitology, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka
| | - Melissa Penny
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Allan Schapira
- Bicol University College of Medicine, Legazpi City, Philippines
| | - Siv Sovannaroth
- National Malaria Program, Ministry of Health, Phnom Penh, Cambodia
| | | | | | - Xiaohong Li
- Global Malaria Programme, WHO, Geneva, Switzerland
| | - Erin Shutes
- Global Malaria Programme, WHO, Geneva, Switzerland
| | | | - Pedro Alonso
- Global Malaria Programme, WHO, Geneva, Switzerland
| | - The WHO Malaria Elimination Steering Group
- Centre for Tropical Medicine and Global Health, University of Oxford, United Kingdom
- Department of Internal Medicine, American University of Beirut, Lebanon
- Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, Canada
- Malaria Consortium, London, United Kingdom
- Public Health Agency, Ministry of Health, Makkah, Saudi Arabia
- Oxford University Clinical Research Unit, Faculty of Medicine Universitas Indonesia, Jakarta, Indonesia
- Department of Medical Microbiology, Radboud University Medical Center, Radboud, the Netherlands
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Tropical Medicine Foundation Dr Heitor Vieira Dourado, Manaus, Brazil
- Department of Parasitology, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
- Bicol University College of Medicine, Legazpi City, Philippines
- National Malaria Program, Ministry of Health, Phnom Penh, Cambodia
- Independent Consultant, Bangkok, Thailand
- Global Malaria Programme, WHO, Geneva, Switzerland
| | | |
Collapse
|
2
|
Abstract
Tropical alluvial gold and gem miners are often an especially at-risk population for malaria infection. Geographical areas of mining-associated malaria epidemics in the recent past include Southeast Asia (Cambodia, Thailand, and Myanmar); the Amazon basin (Brazil, French Guyana, Suriname, Columbia, and Peru); and tropical Africa. Mobile populations of young adult men engaged in the hard labor of mining may experience severe malaria especially if they lack preexisting immunity and are irregularly consuming antimalarial drugs. Particular problems occur because much of this informal mining activity is illegal and done in isolated areas without access to health services and with evidence of emerging antimalarial drug resistance. Concentrating vulnerable populations in an ecologically disturbed landscape is often conducive to epidemics, which can then spread as these highly mobile workers return to their homes. Mining-associated malaria endangers malaria elimination efforts and miners need to be addressed as a group of particular concern.
Collapse
Affiliation(s)
- G. Dennis Shanks
- Australian Defence Force Infectious Disease and Malaria Institute, Enoggera, Australia;,University of Queensland, School of Public Health, Brisbane, Australia;,Address correspondence to G. Dennis Shanks, ADF Malaria and Infectious Disease Institute, Weary Dunlop Dr., Gallipoli Barracks, Enoggera, Queensland 4051, Australia. E-mail:
| | | |
Collapse
|
3
|
Abstract
Asia-Oceania is a diverse region that comprises roughly 65% of the global population at risk for malaria. In 2016 WHO estimated the number of malaria cases across the Asia-Oceania to be 17 million, which is only a small part (8%) of the total global malaria burden, and the number of cases is shrinking rapidly. Most countries have brought their cases down to the point where elimination is in sight. Plasmodium vivax (P. vivax) is becoming the dominant malaria species in many of those countries, where malaria occurs in hot spots of transmission frequently along international borders. The challenge is now to concentrate on those areas. This chapter reviews the situation in various areas of the Region and focuses on a number of important issues, including the prevalence of P. vivax and drug-resistant malaria.
Collapse
Affiliation(s)
| | | | - Kevin Palmer
- Department of Tropical Medicine and Pharmacology, John A. Burns School of Medicine, Honolulu, HI, USA
| |
Collapse
|
4
|
Thriemer K, Bobogare A, Ley B, Gudo CS, Alam MS, Anstey NM, Ashley E, Baird JK, Gryseels C, Jambert E, Lacerda M, Laihad F, Marfurt J, Pasaribu AP, Poespoprodjo JR, Sutanto I, Taylor WR, van den Boogaard C, Battle KE, Dysoley L, Ghimire P, Hawley B, Hwang J, Khan WA, Mudin RNB, Sumiwi ME, Ahmed R, Aktaruzzaman MM, Awasthi KR, Bardaji A, Bell D, Boaz L, Burdam FH, Chandramohan D, Cheng Q, Chindawongsa K, Culpepper J, Das S, Deray R, Desai M, Domingo G, Duoquan W, Duparc S, Floranita R, Gerth-Guyette E, Howes RE, Hugo C, Jagoe G, Sariwati E, Jhora ST, Jinwei W, Karunajeewa H, Kenangalem E, Lal BK, Landuwulang C, Le Perru E, Lee SE, Makita LS, McCarthy J, Mekuria A, Mishra N, Naket E, Nambanya S, Nausien J, Duc TN, Thi TN, Noviyanti R, Pfeffer D, Qi G, Rahmalia A, Rogerson S, Samad I, Sattabongkot J, Satyagraha A, Shanks D, Sharma SN, Sibley CH, Sungkar A, Syafruddin D, Talukdar A, Tarning J, ter Kuile F, Thapa S, Theodora M, Huy TT, Waramin E, Waramori G, Woyessa A, Wongsrichanalai C, Xa NX, Yeom JS, Hermawan L, Devine A, Nowak S, Jaya I, Supargiyono S, Grietens KP, Price RN. Quantifying primaquine effectiveness and improving adherence: a round table discussion of the APMEN Vivax Working Group. Malar J 2018; 17:241. [PMID: 29925430 PMCID: PMC6011582 DOI: 10.1186/s12936-018-2380-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 06/08/2018] [Indexed: 01/13/2023] Open
Abstract
The goal to eliminate malaria from the Asia-Pacific by 2030 will require the safe and widespread delivery of effective radical cure of malaria. In October 2017, the Asia Pacific Malaria Elimination Network Vivax Working Group met to discuss the impediments to primaquine (PQ) radical cure, how these can be overcome and the methodological difficulties in assessing clinical effectiveness of radical cure. The salient discussions of this meeting which involved 110 representatives from 18 partner countries and 21 institutional partner organizations are reported. Context specific strategies to improve adherence are needed to increase understanding and awareness of PQ within affected communities; these must include education and health promotion programs. Lessons learned from other disease programs highlight that a package of approaches has the greatest potential to change patient and prescriber habits, however optimizing the components of this approach and quantifying their effectiveness is challenging. In a trial setting, the reactivity of participants results in patients altering their behaviour and creates inherent bias. Although bias can be reduced by integrating data collection into the routine health care and surveillance systems, this comes at a cost of decreasing the detection of clinical outcomes. Measuring adherence and the factors that relate to it, also requires an in-depth understanding of the context and the underlying sociocultural logic that supports it. Reaching the elimination goal will require innovative approaches to improve radical cure for vivax malaria, as well as the methods to evaluate its effectiveness.
Collapse
Affiliation(s)
- Kamala Thriemer
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Darwin, NT 0810 Australia
| | - Albino Bobogare
- Ministry of Health and Medical Services, National Vector-Borne Disease Control Programme, Honiara, Solomon Islands
| | - Benedikt Ley
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Darwin, NT 0810 Australia
| | | | - Mohammad Shafiul Alam
- 0000 0004 0600 7174grid.414142.6International Center for Diarrheal Diseases (ICDDR,B), Dhaka, Bangladesh
| | - Nick M. Anstey
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Darwin, NT 0810 Australia
| | - Elizabeth Ashley
- Myanmar-Oxford Clinical Research Unit, Yangon, Myanmar ,0000 0004 1936 8948grid.4991.5Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - J. Kevin Baird
- 0000 0004 1936 8948grid.4991.5Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK ,0000 0004 1795 0993grid.418754.bEijkman-Oxford Clinical Research Unit, Jakarta, Indonesia
| | - Charlotte Gryseels
- 0000 0001 2153 5088grid.11505.30Institute of Tropical Medicine Antwerp, Antwerp, Belgium
| | - Elodie Jambert
- 0000 0004 0432 5267grid.452605.0Medicines for Malaria Venture (MMV), Geneva, Switzerland
| | - Marcus Lacerda
- Instituto Leônidas & Maria Deane (Fiocruz), Manaus, Amazonas Brazil ,0000 0004 0486 0972grid.418153.aFundação de Medicina Tropical Dr, Heitor Vieira Dourado, Manaus, Amazonas Brazil
| | - Ferdinand Laihad
- National Forum on Indonesia RBM/National Forum on Gebrak Malaria, Jakarta, Indonesia
| | - Jutta Marfurt
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Darwin, NT 0810 Australia
| | | | | | - Inge Sutanto
- 0000000120191471grid.9581.5University of Indonesia, Jakarta, Indonesia
| | - Walter R. Taylor
- 0000 0004 1936 8948grid.4991.5Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK ,Mahidol Oxford Clinical Research Unit (MORU), Bangkok, Thailand
| | - Christel van den Boogaard
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Darwin, NT 0810 Australia
| | - Katherine E. Battle
- 0000 0004 1936 8948grid.4991.5Malaria Atlas Project (MAP), Big Data Institute, University of Oxford, Oxford, UK
| | - Lek Dysoley
- grid.452707.3National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia ,grid.436334.5School of Public Health, National Institute of Public Health, Phnom Penh, Cambodia
| | - Prakash Ghimire
- 0000 0001 2114 6728grid.80817.36Microbiology Department, Tribhuvan University, Kathmandu, Nepal
| | - Bill Hawley
- 0000 0001 2163 0069grid.416738.fEntomology Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, USA
| | - Jimee Hwang
- 0000 0001 2163 0069grid.416738.fPresident’s Malaria Initiative, Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, USA ,0000 0001 2297 6811grid.266102.1Global Health Group, University of California San Francisco, San Francisco, USA
| | - Wasif Ali Khan
- 0000 0004 0600 7174grid.414142.6International Center for Diarrheal Diseases (ICDDR,B), Dhaka, Bangladesh
| | - Rose Nani Binti Mudin
- 0000 0001 0690 5255grid.415759.bDisease Control Division, Ministry of Health, Putrajaya, Malaysia
| | | | - Rukhsana Ahmed
- 0000 0004 1936 9764grid.48004.38Liverpool School of Tropical Medicine, Liverpool, UK
| | - M. M. Aktaruzzaman
- grid.466907.aDirectorate General of Health Services, Ministry of Health & Family Welfare Government of the People’s Republic of Bangladesh, Dhaka, Bangladesh
| | | | - Azucena Bardaji
- 0000 0000 9635 9413grid.410458.cISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - David Bell
- 0000 0004 0406 7608grid.471104.7Intellectual Ventures Global Good Fund, Bellevue, USA
| | - Leonard Boaz
- Ministry of Health and Medical Services, National Vector-Borne Disease Control Programme, Honiara, Solomon Islands
| | | | - Daniel Chandramohan
- 0000 0004 0425 469Xgrid.8991.9The London School of Hygiene & Tropical Medicine (LSHTM), London, UK
| | - Qin Cheng
- Australian Defence Force Malaria and Infectious Disease Institute, Enoggera, Australia
| | | | - Janice Culpepper
- 0000 0000 8990 8592grid.418309.7Bill & Melinda Gates Foundation, Seattle, USA
| | - Santasabuj Das
- 0000 0004 1767 225Xgrid.19096.37Indian Council of Medical Research, New Delhi, India
| | - Raffy Deray
- Department of Health, National Centre for Disease Control & Prevention, Manila, Philippines
| | - Meghna Desai
- 0000 0001 2163 0069grid.416738.fMalaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, USA
| | | | - Wang Duoquan
- 0000 0000 8803 2373grid.198530.6National Institute of Parasitic Diseases, China CDC, Shanghai, China
| | - Stephan Duparc
- 0000 0004 0432 5267grid.452605.0Medicines for Malaria Venture (MMV), Geneva, Switzerland
| | | | | | - Rosalind E. Howes
- 0000 0004 1936 8948grid.4991.5Malaria Atlas Project (MAP), Big Data Institute, University of Oxford, Oxford, UK
| | | | - George Jagoe
- 0000 0004 0432 5267grid.452605.0Medicines for Malaria Venture (MMV), Geneva, Switzerland
| | - Elvieda Sariwati
- 0000 0004 0470 8161grid.415709.eMinistry of Health, National Malaria Control Program, Jakarta, Indonesia
| | - Sanya Tahmina Jhora
- grid.466907.aDirectorate General of Health Services, Ministry of Health & Family Welfare Government of the People’s Republic of Bangladesh, Dhaka, Bangladesh
| | - Wu Jinwei
- Tengchong Center for Disease Control and Prevention, Tengchong, China
| | - Harin Karunajeewa
- grid.1042.7Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Enny Kenangalem
- Yayasan Pengembangan Kesehatan dan Masyarakat, Papua (YPKMP), Papua, Indonesia
| | - Bibek Kumar Lal
- Epidemiology & Disease Control Division, Department of Health Services, Ministry of Health and Population, Kathmandu, Nepal
| | | | | | - Sang-Eun Lee
- 0000 0004 1763 8617grid.418967.5Division of Vectors and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Seoul, South Korea
| | - Leo Sora Makita
- Ministry of Health, National Malaria Control Programme, Port Mosby, Papua New Guinea
| | - James McCarthy
- 0000 0001 2294 1395grid.1049.cQIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Asrat Mekuria
- 0000 0001 1250 5688grid.7123.7School of Medicine, Addis Ababa University, Addis Ababa, Ethiopia
| | - Neelima Mishra
- 0000 0004 1767 225Xgrid.19096.37Indian Council of Medical Research, New Delhi, India
| | - Esau Naket
- Ministry of Health, Malaria and Other Vector-Borne Diseases Control Program (MOVBDCP), Port Vila, Vanuatu
| | - Simone Nambanya
- Center of Malariology, Parasitology and Entomology, Communicable Diseases Control, Vientiane, Lao PDR
| | - Johnny Nausien
- Ministry of Health, Malaria and Other Vector-Borne Diseases Control Program (MOVBDCP), Port Vila, Vanuatu
| | - Thang Ngo Duc
- grid.452658.8National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | - Thuan Nguyen Thi
- grid.452658.8National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | - Rinitis Noviyanti
- 0000 0004 1795 0993grid.418754.bEijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Daniel Pfeffer
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Darwin, NT 0810 Australia ,0000 0004 1936 8948grid.4991.5Malaria Atlas Project (MAP), Big Data Institute, University of Oxford, Oxford, UK
| | - Gao Qi
- grid.452515.2Jiangsu Institute of Parasitic Diseases, Wuxi, China ,WHO Collaborative Centre for Research and Training of Malaria Elimination, Wuxi, China
| | - Annisa Rahmalia
- 0000 0004 1796 1481grid.11553.33Tuberculosis-HIV Research Center Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia ,0000000122931605grid.5590.9Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Stephen Rogerson
- 0000 0001 2179 088Xgrid.1008.9Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, Australia
| | - Iriani Samad
- 0000 0004 0470 8161grid.415709.eMinistry of Health, National Malaria Control Program, Jakarta, Indonesia
| | - Jetsumon Sattabongkot
- 0000 0004 1937 0490grid.10223.32Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Bangok, Thailand
| | - Ari Satyagraha
- 0000 0004 1795 0993grid.418754.bEijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Dennis Shanks
- Australian Defence Force Malaria and Infectious Disease Institute, Enoggera, Australia
| | - Surender Nath Sharma
- grid.415820.aNational Vector Borne Disease Control Programme Directorate General of Health Services Ministry of Health & Family Welfare, New Delhi, India
| | - Carol Hopkins Sibley
- WorldWide Antimalarial Resistance Network (WWARN), Oxford, UK ,0000000122986657grid.34477.33University of Washington, Seattle, WA USA
| | - Ali Sungkar
- 0000 0004 0470 8161grid.415709.eFamily Health Directorate, Ministry of Health, Jakarta, Indonesia
| | - Din Syafruddin
- 0000 0004 1795 0993grid.418754.bEijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Arunansu Talukdar
- 0000 0004 1768 2335grid.413204.0Medicine Department, Medical College Kolkata, Kolkata, India
| | - Joel Tarning
- Mahidol Oxford Clinical Research Unit (MORU), Bangkok, Thailand
| | - Feiko ter Kuile
- 0000 0004 1936 9764grid.48004.38Liverpool School of Tropical Medicine, Liverpool, UK ,0000 0001 0155 5938grid.33058.3dKenya Medical Research Institute (KEMRI) Centre for Global Health Research, Kisumu, Kenya
| | | | - Minerva Theodora
- 0000 0004 0470 8161grid.415709.eMinistry of Health, National Malaria Control Program, Jakarta, Indonesia
| | - Tho Tran Huy
- grid.452658.8National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | - Edward Waramin
- Family Health Services, Ministry of Health, Port Mosby, Papua New Guinea
| | | | - Adugna Woyessa
- grid.452387.fEthiopian Public Health Institute (EPHI), Addis Ababa, Ethiopia
| | | | - Nguyen Xuan Xa
- grid.452658.8National Institute of Malariology, Parasitology and Entomology (NIMPE), Hanoi, Vietnam
| | - Joon Sup Yeom
- 0000 0004 0470 5454grid.15444.30Yonsei University College of Medicine, Seoul, South Korea
| | - Lukas Hermawan
- 0000 0004 0470 8161grid.415709.eFamily Health Directorate, Ministry of Health, Jakarta, Indonesia
| | - Angela Devine
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Darwin, NT 0810 Australia ,0000 0004 1936 8948grid.4991.5Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK ,Mahidol Oxford Clinical Research Unit (MORU), Bangkok, Thailand
| | - Spike Nowak
- 0000 0000 8940 7771grid.415269.dPATH, Seattle, USA
| | - Indra Jaya
- Program and Information Department, Directorate General of Disease Prevention and Control, Jakarta, Indonesia
| | | | - Koen Peeters Grietens
- 0000 0001 2153 5088grid.11505.30Institute of Tropical Medicine Antwerp, Antwerp, Belgium
| | - Ric N. Price
- 0000 0000 8523 7955grid.271089.5Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Darwin, NT 0810 Australia ,0000 0004 1936 8948grid.4991.5Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| |
Collapse
|
5
|
Kitchakarn S, Lek D, Thol S, Hok C, Saejeng A, Huy R, Chinanonwait N, Thimasarn K, Wongsrichanalai C. Implementation of G6PD testing and primaquine for P. vivax radical cure: Operational perspectives from Thailand and Cambodia. WHO South East Asia J Public Health 2018; 6:60-68. [PMID: 28857064 DOI: 10.4103/2224-3151.213793] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Following progressive success in reducing the burden of malaria over the past two decades, countries of the Asia Pacific are now aiming for elimination of malaria by 2030. Plasmodium falciparum and Plasmodium vivax are the two main malaria species that are endemic in the region. P. vivax is generally perceived to be less severe but will be harder to eliminate, owing partly to its dormant liver stage (known as a hypnozoite) that can cause multiple relapses following an initial clinical episode caused by a mosquito-borne infection. Primaquine is the only anti-hypnozoite drug against P. vivax relapse currently available, with tafenoquine in the pipeline. However, both drugs may cause severe haemolysis in individuals with deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD), a hereditary defect. The overall incidence of malaria has significantly declined in both Thailand and Cambodia over the last 15 years. However, P. vivax has replaced P. falciparum as the dominant species in large parts of both countries. This paper presents the experience of the national malaria control programmes of the two countries, in their efforts to implement safe primaquine therapy for the radical cure, i.e. relapse prevention, of P. vivax malaria by introducing a rapid, point-of-care test to screen for G6PD deficiency.
Collapse
Affiliation(s)
- Suravadee Kitchakarn
- Bureau of Vector Borne Diseases, Ministry of Public Health, Nonthaburi, Thailand
| | - Dysoley Lek
- National Centre for Parasitology, Entomology and Malaria Control; School of Public Health, National Institute of Public Health, Phnom Penh, Cambodia, Thailand
| | - Sea Thol
- Cambodian Pharmacovigilance Centre, Department of Drugs and Food, Ministry of Health, Phnom Penh, Cambodia
| | - Chantheasy Hok
- National Centre for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Aungkana Saejeng
- Office of Disease Prevention and Control No. 10, Chiang Mai, Thailand
| | - Rekol Huy
- National Centre for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Nipon Chinanonwait
- Bureau of Vector Borne Diseases, Ministry of Public Health, Nonthaburi, Thailand
| | | | | |
Collapse
|
6
|
Olliaro PL, Barnwell JW, Barry A, Mendis K, Mueller I, Reeder JC, Shanks GD, Snounou G, Wongsrichanalai C. Implications of Plasmodium vivax Biology for Control, Elimination, and Research. Am J Trop Med Hyg 2016; 95:4-14. [PMID: 27799636 PMCID: PMC5201222 DOI: 10.4269/ajtmh.16-0160] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Accepted: 09/29/2016] [Indexed: 12/03/2022] Open
Abstract
This paper summarizes our current understanding of the biology of Plasmodium vivax, how it differs from Plasmodium falciparum, and how these differences explain the need for P. vivax-tailored interventions. The article further pinpoints knowledge gaps where investments in research are needed to help identify and develop such specific interventions. The principal obstacles to reduce and eventually eliminate P. vivax reside in 1) its higher vectorial capacity compared with P. falciparum due to its ability to develop at lower temperature and over a shorter sporogonic cycle in the vector, allowing transmission in temperate zones and making it less sensitive to vector control measures that are otherwise effective on P. falciparum; 2) the presence of dormant liver forms (hypnozoites), sustaining multiple relapsing episodes from a single infectious bite that cannot be diagnosed and are not susceptible to any available antimalarial except primaquine, with routine deployment restricted by toxicity; 3) low parasite densities, which are difficult to detect with current diagnostics leading to missed diagnoses and delayed treatments (and protracted transmission), coupled with 4) transmission stages (gametocytes) occurring early in acute infections, before infection is diagnosed.
Collapse
Affiliation(s)
- Piero L Olliaro
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.,UNICEF/UNDP/World Bank/WHO Special Programme on Research and Training in Tropical Diseases (TDR), World Health Organization, Geneva, Switzerland
| | - John W Barnwell
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Alyssa Barry
- Department of Medical Biology, University of Melbourne, Melbourne, Australia.,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | | | - Ivo Mueller
- Institute of Global Health (ISGLOBAL), Barcelona, Spain.,Division of Population Health and Immunity, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - John C Reeder
- UNICEF/UNDP/World Bank/WHO Special Programme on Research and Training in Tropical Diseases (TDR), World Health Organization, Geneva, Switzerland
| | - G Dennis Shanks
- School of Population Health, University of Queensland, Brisbane, Australia
| | - Georges Snounou
- Centre d'Immunologie et de Maladies Infectieuses (CIMI)-Paris, Institut National de la Santé et de la Recherche Médicale (INSERM) U1135-Centre National de la Recherche Scientifique (CNRS) ERL 8255, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, UPMC UMRS CR7, Paris, France
| | | |
Collapse
|
7
|
Mammadov S, Gasimov E, Kurdova-Mintcheva R, Wongsrichanalai C. Elimination of Plasmodium vivax Malaria in Azerbaijan. Am J Trop Med Hyg 2016; 95:78-86. [PMID: 27708184 PMCID: PMC5201226 DOI: 10.4269/ajtmh.16-0173] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 08/19/2016] [Indexed: 11/07/2022] Open
Abstract
Azerbaijan in the south caucasus region of far southeastern Europe has a long history of malaria endemicity but just successfully eliminated local transmission. After a period of relatively stable malaria situation (1960-1970), the country witnessed an epidemic followed by a series of outbreaks of various magnitudes in the following two decades, all caused by Plasmodium vivax Compared with 1993, the number of malaria cases in the country jumped 29 times in 1994, 123 times in 1995, and 571 times in 1996 at the peak of the epidemic, when 13,135 cases were officially registered. Incidence rate increased dramatically from 0.2/100,000 population in 1991 to over 17/100,000 population in 1996. Scaled-up malaria control led to the containment of the epidemic and to a dramatic decrease of malaria burden nationwide. Azerbaijan has applied contemporary, complex control and surveillance strategies and approaches and is currently in the prevention of reintroduction phase. This article describes Azerbaijan's public health experience in conducting malaria control and elimination interventions over several decades until 2013 when the country reached an important milestone-no indigenous malaria cases were recorded.
Collapse
Affiliation(s)
- Suleyman Mammadov
- Republican Center for Hygiene and Epidemiology, Ministry of Health, Baku, Azerbaijan
| | - Elkhan Gasimov
- Malaria and Other Vector-Borne and Parasitic Diseases, World Health Organization Regional Office for Europe, Copenhagen, Denmark
| | | | | |
Collapse
|
8
|
Bassat Q, Velarde M, Mueller I, Lin J, Leslie T, Wongsrichanalai C, Baird JK. Key Knowledge Gaps for Plasmodium vivax Control and Elimination. Am J Trop Med Hyg 2016; 95:62-71. [PMID: 27430544 PMCID: PMC5201224 DOI: 10.4269/ajtmh.16-0180] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 05/11/2016] [Indexed: 11/18/2022] Open
Abstract
There is inadequate understanding of the biology, pathology, transmission, and control of Plasmodium vivax, the geographically most widespread cause of human malaria. During the last decades, study of this species was neglected, in part due to the erroneous belief that it is intrinsically benign. In addition, many technical challenges in culturing the parasite also hampered understanding its fundamental biology and molecular and cellular responses to chemotherapeutics. Research on vivax malaria needs to be substantially expanded over the next decade to accelerate its elimination and eradication. This article summarizes key knowledge gaps identified by researchers, national malaria control programs, and other stakeholders assembled by the World Health Organization to develop strategies for controlling and eliminating vivax malaria. The priorities presented in this article emerged in these technical discussions, and were adopted by expert consensus of the authors. All involved understood the priority placed upon pragmatism in this research agenda, that is, focus upon tools delivering better prevention, diagnosis, treatment, and surveillance of P. vivax.
Collapse
Affiliation(s)
- Quique Bassat
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain.,Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Mar Velarde
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
| | - Ivo Mueller
- Population Health and Immunology Division, Walter and Eliza Hall Institute, Victoria, Australia
| | - Jessica Lin
- Division of Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina
| | - Toby Leslie
- Health Protection and Research Organisation, Kabul, Afghanistan.,London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - J Kevin Baird
- Centre for Tropical Medicine, University of Oxford, Oxford, United Kingdom.,Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia
| |
Collapse
|
9
|
Lalani T, Tisdale MD, Maguire JD, Wongsrichanalai C, Riddle MS, Tribble DR. Detection of enteropathogens associated with travelers' diarrhea using a multiplex Luminex-based assay performed on stool samples smeared on Whatman FTA Elute cards. Diagn Microbiol Infect Dis 2015; 83:18-20. [PMID: 26072151 DOI: 10.1016/j.diagmicrobio.2015.05.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 04/27/2015] [Accepted: 05/19/2015] [Indexed: 01/03/2023]
Abstract
We evaluated the limits of detection (LoD) for an 11-plex PCR-Luminex assay performed on Whatman(™) FTA Elute cards smeared with stool containing pathogens associated with travelers' diarrhea. LoDs ranged from 10(2) to 10(5)CFU, PFU, or cysts/g for most pathogens except Cryptosporidium. Campylobacter and norovirus LoDs increased with prolonged storage of cards.
Collapse
Affiliation(s)
- Tahaniyat Lalani
- Infectious Disease Clinic, Naval Medical Center, Portsmouth, VA, USA; Infectious Disease Clinical Research Program, Uniformed Services University, Bethesda, MD, USA; Henry M Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA.
| | - Michele D Tisdale
- Infectious Disease Clinic, Naval Medical Center, Portsmouth, VA, USA; Infectious Disease Clinical Research Program, Uniformed Services University, Bethesda, MD, USA; Henry M Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Jason D Maguire
- Infectious Disease Clinic, Naval Medical Center, Portsmouth, VA, USA
| | | | - Mark S Riddle
- Enteric Diseases Department, Naval Medical Research Center, Silver Spring, MD, USA
| | - David R Tribble
- Infectious Disease Clinical Research Program, Uniformed Services University, Bethesda, MD, USA
| |
Collapse
|
10
|
Talundzic E, Okoth SA, Congpuong K, Plucinski MM, Morton L, Goldman IF, Kachur PS, Wongsrichanalai C, Satimai W, Barnwell JW, Udhayakumar V. Correction: selection and spread of artemisinin-resistant alleles in Thailand prior to the global artemisinin resistance containment campaign. PLoS Pathog 2015; 11:e1004862. [PMID: 25901903 PMCID: PMC4406843 DOI: 10.1371/journal.ppat.1004862] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
11
|
Talundzic E, Okoth SA, Congpuong K, Plucinski MM, Morton L, Goldman IF, Kachur PS, Wongsrichanalai C, Satimai W, Barnwell JW, Udhayakumar V. Selection and spread of artemisinin-resistant alleles in Thailand prior to the global artemisinin resistance containment campaign. PLoS Pathog 2015; 11:e1004789. [PMID: 25836766 PMCID: PMC4383523 DOI: 10.1371/journal.ppat.1004789] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 03/06/2015] [Indexed: 11/18/2022] Open
Abstract
The recent emergence of artemisinin resistance in the Greater Mekong Subregion poses a major threat to the global effort to control malaria. Tracking the spread and evolution of artemisinin-resistant parasites is critical in aiding efforts to contain the spread of resistance. A total of 417 patient samples from the year 2007, collected during malaria surveillance studies across ten provinces in Thailand, were genotyped for the candidate Plasmodium falciparum molecular marker of artemisinin resistance K13. Parasite genotypes were examined for K13 propeller mutations associated with artemisinin resistance, signatures of positive selection, and for evidence of whether artemisinin-resistant alleles arose independently across Thailand. A total of seven K13 mutant alleles were found (N458Y, R539T, E556D, P574L, R575K, C580Y, S621F). Notably, the R575K and S621F mutations have previously not been reported in Thailand. The most prevalent artemisinin resistance-associated K13 mutation, C580Y, carried two distinct haplotype profiles that were separated based on geography, along the Thai-Cambodia and Thai-Myanmar borders. It appears these two haplotypes may have independent evolutionary origins. In summary, parasites with K13 propeller mutations associated with artemisinin resistance were widely present along the Thai-Cambodia and Thai-Myanmar borders prior to the implementation of the artemisinin resistance containment project in the region. The Plasmodium falciparum parasites that cause malaria are evolving resistance to our most effective and potent anti-malarial drugs available, called artemisinins. Currently, artemisinin resistance is emerging in a number of countries in the Greater Mekong Subregion, including Cambodia, Thailand, Myanmar, and Vietnam. Historically, the Thai-Cambodia border region has been an epicenter of resistance to several anti-malarial drugs. To prevent the spread of artemisinin resistant parasites from the Greater Mekong Subregion, a global artemisinin resistance project was initiated in 2009. Here, we show that artemisinin resistance associated mutation in the K13 gene were widely present throughout Thailand, as early as 2007, primarily along the Thai-Cambodia and Thai-Myanmar border regions. Additional data based on microsatellite markers suggests that the most commonly found K13 C580Y allele may have two recent independent origins in Thailand, on the borders of Cambodia and Myanmar.
Collapse
Affiliation(s)
- Eldin Talundzic
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- Atlanta Research and Education Foundation, Atlanta VA Medical Center, Atlanta, Georgia, United States of America
- * E-mail:
| | - Sheila Akinyi Okoth
- Atlanta Research and Education Foundation, Atlanta VA Medical Center, Atlanta, Georgia, United States of America
| | - Kanungnit Congpuong
- Bureau of Vector Borne Diseases, Ministry of Public Health, Nonthaburi, Thailand
- Bansomdej-chaopraya Rajabhat University, Bangkok, Thailand
| | - Mateusz M. Plucinski
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Lindsay Morton
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Ira F. Goldman
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Patrick S. Kachur
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | | | - Wichai Satimai
- Bureau of Vector Borne Diseases, Ministry of Public Health, Nonthaburi, Thailand
| | - John W. Barnwell
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Venkatachalam Udhayakumar
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| |
Collapse
|
12
|
Wongsrichanalai C, Sibley C. Fighting drug-resistant Plasmodium falciparum: the challenge of artemisinin resistance. Clin Microbiol Infect 2013; 19:908-16. [DOI: 10.1111/1469-0691.12316] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
13
|
Lin JT, Patel JC, Kharabora O, Sattabongkot J, Muth S, Ubalee R, Schuster AL, Rogers WO, Wongsrichanalai C, Juliano JJ. Plasmodium vivax isolates from Cambodia and Thailand show high genetic complexity and distinct patterns of P. vivax multidrug resistance gene 1 (pvmdr1) polymorphisms. Am J Trop Med Hyg 2013; 88:1116-23. [PMID: 23509126 DOI: 10.4269/ajtmh.12-0701] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Plasmodium vivax accounts for an increasing fraction of malaria infections in Thailand and Cambodia. We compared P. vivax genetic complexity and antimalarial resistance patterns in the two countries. Use of a heteroduplex tracking assay targeting the merozoite surface protein 1 gene revealed that vivax infections in both countries are frequently polyclonal (84%), with parasites that are highly diverse (HE = 0.86) but closely related (GST = 0.18). Following a history of different drug policies in Thailand and Cambodia, distinct patterns of antimalarial resistance have emerged: most Cambodian isolates harbor the P. vivax multidrug resistance gene 1 (pvmdr1) 976F mutation associated with chloroquine resistance (89% versus 8%, P < 0.001), whereas Thai isolates more often display increased pvmdr1 copy number (39% versus 4%, P < 0.001). Finally, genotyping of paired isolates from individuals suspected of suffering relapse supports a complex scheme of relapse whereby recurrence of multiple identical variants is sometimes accompanied by the appearance of novel variants.
Collapse
Affiliation(s)
- Jessica T Lin
- Division of Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Wongsrichanalai C. Artemisinin resistance or artemisinin-based combination therapy resistance? The Lancet Infectious Diseases 2013; 13:114-5. [DOI: 10.1016/s1473-3099(12)70349-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
15
|
Bustos MD, Wongsrichanalai C, Delacollette C, Burkholder B. Monitoring antimalarial drug efficacy in the Greater Mekong Subregion: an overview of in vivo results from 2008 to 2010. Southeast Asian J Trop Med Public Health 2013; 44 Suppl 1:201-307. [PMID: 24159833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In vivo Therapeutic Efficacy Studies (TES) have been routinely conducted in the Greater Mekong Subregion (GMS) for decades. Results from the last 10 years have contributed to update national antimalarial drug policies, to identify hotspots of multi-drug resistance and from 2008 onwards, to stimulate ambitious multi-country programs and innovative research projects to contain and eliminate artemisinin resistant Plasmodium falciparum strains in the subregion. This paper describes the results of TES of first-line antimalarials in six countries of the GMS from 2008-2010 using the WHO in vivo standard protocol. A total of 91 studies were conducted at 32 sentinel sites testing dihydroartemisinin-piperaquine (DHA-PIP), artesunate+mefloquine (A+M), and artemether-lumefantrine (AL) against P. falciparum malaria, as well as chloroquine and DHA-PIP against P vivax. Overall, artemisinin-based combination therapies (ACTs) remained efficacious against falciparum malaria with some exceptions. The 42-day adequate clinical and parasitological response (ACPR) for DHA-PIP dropped significantly to 73% (95% CI 53-87) in 2010 in the same hotspot area of western Cambodia known to harbor artemisinin resistant P. falciparum strains. Because P falciparum sensitivity to artemisinin is a major concern, especially on the Cambodia-Thailand border, attempts were also made to strengthen the monitoring of parasite clearance time elsewhere in the region and globally. The proportion of patients still blood-smear positive on Day 3 above 10% is considered a proxy indicator to strongly suspect the appearance of falciparum resistance to artesunate. This has led to substantial extra measures to confirm the suspicion and eventually set up interventions to eliminate artemisinin resistant parasites. Notably, increasing proportions (>10%) of Day 3 positives among falciparum malaria patients treated with DHA-PIP have been observed in western Cambodia, Myanmar, Viet Nam and China from 2008. Percent Day 3 parasitemia associated with A+M has increased along the Thailand-Myanmar border to surpass 10% at several sites, adding to the known pool of sites with 'suspected' artemisinin resistance in the GMS. Chloroquine remains highly effective against P. vivax except for northeastern and north-central Cambodia. TES results from this subregional-wide monitoring of antimalarial efficacy have influenced the changes of 1st line drugs against both P. falciparum and P. vivax in Cambodia, against P. falciparum in selected areas in Thailand, and pinpointed hotspot areas elsewhere that should be closely monitored in order to take action in a timely manner.
Collapse
|
16
|
Vijaykadga S, Alker AP, Satimai W, MacArthur JR, Meshnick SR, Wongsrichanalai C. Delayed Plasmodium falciparum clearance following artesunate-mefloquine combination therapy in Thailand, 1997-2007. Malar J 2012; 11:296. [PMID: 22929382 PMCID: PMC3478203 DOI: 10.1186/1475-2875-11-296] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 08/20/2012] [Indexed: 11/17/2022] Open
Abstract
Background There is concern that artesunate resistance is developing in Southeast Asia. The purpose of this study is to investigate the prevalence of parasitaemia in the few days following treatment with artesunate-mefloquine (AM), which is an indirect measure of decreased artesunate susceptibility. Methods This is a retrospective analysis of 31 therapeutic efficacy studies involving 1,327 patients treated with AM conducted by the Thai National Malaria Control Programme from 1997–2007. Results The prevalence of patients with parasitaemia on day 2 was higher in the east compared to the west (east: 20%, west: 9%, OR 2.47, 95% CI: 1.77, 3.45). In addition, the prevalence of day-2 parasitaemia increased over time (OR for each year = 1.10, 95% CI: 1.03, 1.19). After controlling for initial parasitaemia and age, year and region remained important determinants of day-2 parasitaemia (OR for region = 3.98, 95%CI 2.63, 6.00; OR for year = 1.28, 95%CI: 1.17, 1.39). The presence of parasitaemia on day 2 and day 3 were specific, but not sensitive predictors of treatment failure. Discussion Delayed resolution of parasitaemia after AM treatment increased in eastern Thailand between 1997 and 2007, which may be an early manifestation of decreased artesunate susceptibility. However, clinical and parasitological treatment failure after 28 days (which is related to both mefloquine and artesunate decreased susceptibility) is not changing over time. The presence of parasitaemia on day 2 is a poor indicator of AM 28-day treatment failure.
Collapse
Affiliation(s)
- Saowanit Vijaykadga
- Bureau of Vector Borne Diseases, Department of Diseases Control, Ministry of Public Health, Nonthaburi, Thailand
| | | | | | | | | | | |
Collapse
|
17
|
Banoo S, Bell D, Bossuyt P, Herring A, Mabey D, Poole F, Smith PG, Sriram N, Wongsrichanalai C, Linke R, O'Brien R, Perkins M, Cunningham J, Matsoso P, Nathanson CM, Olliaro P, Peeling RW, Ramsay A. Evaluation of diagnostic tests for infectious diseases: general principles. Nat Rev Microbiol 2010; 8:S17-S29. [PMID: 21548184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
|
18
|
Abstract
Emergence of artemisinin resistance is reason to revise the definition of drug resistance for malaria.
Collapse
|
19
|
Vinayak S, Alam MT, Sem R, Shah NK, Susanti AI, Lim P, Muth S, Maguire JD, Rogers WO, Fandeur T, Barnwell JW, Escalante AA, Wongsrichanalai C, Ariey F, Meshnick SR, Udhayakumar V. Multiple genetic backgrounds of the amplified Plasmodium falciparum multidrug resistance (pfmdr1) gene and selective sweep of 184F mutation in Cambodia. J Infect Dis 2010; 201:1551-60. [PMID: 20367478 DOI: 10.1086/651949] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND The emergence of artesunate-mefloquine (AS+MQ)-resistant Plasmodium falciparum in the Thailand-Cambodia region is a major concern for malaria control. Studies indicate that copy number increase and key alleles in the pfmdr1 gene are associated with AS+MQ resistance. In the present study, we investigated evidence for a selective sweep around pfmdr1 because of the spread of adaptive mutation and/or multiple copies of this gene in the P. falciparum population in Cambodia. METHODS We characterized 13 microsatellite loci flanking (+/-99 kb) pfmdr1 in 93 single-clone P. falciparum infections, of which 31 had multiple copies and 62 had a single copy of the pfmdr1 gene. RESULTS Genetic analysis revealed no difference in the mean (+/- standard deviation) expected heterozygosity (H(e)) at loci around single (0.75+/-0.03) and multiple (0.76+/-0.04) copies of pfmdr1. Evidence of genetic hitchhiking with the selective sweep of certain haplotypes was seen around mutant (184F) pfmdr1 allele, irrespective of the copy number. There was an overall reduction of 28% in mean H(e) (+/-SD) around mutant allele (0.56+/-0.05), compared with wild-type allele (0.84+/-0.02). Significant linkage disequilibrium was also observed between the loci flanking mutant pfmdr1 allele. CONCLUSION The 184F mutant allele is under selection, whereas amplification of pfmdr1 gene in this population occurs on multiple genetic backgrounds.
Collapse
Affiliation(s)
- Sumiti Vinayak
- Atlanta Research and Education Foundation, Atlanta, Georgia, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Vinayak S, Alam MT, Mixson-Hayden T, McCollum AM, Sem R, Shah NK, Lim P, Muth S, Rogers WO, Fandeur T, Barnwell JW, Escalante AA, Wongsrichanalai C, Ariey F, Meshnick SR, Udhayakumar V. Origin and evolution of sulfadoxine resistant Plasmodium falciparum. PLoS Pathog 2010; 6:e1000830. [PMID: 20360965 PMCID: PMC2847944 DOI: 10.1371/journal.ppat.1000830] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Accepted: 02/22/2010] [Indexed: 11/29/2022] Open
Abstract
The Thailand-Cambodia border is the epicenter for drug-resistant falciparum malaria. Previous studies have shown that chloroquine (CQ) and pyrimethamine resistance originated in this region and eventually spread to other Asian countries and Africa. However, there is a dearth in understanding the origin and evolution of dhps alleles associated with sulfadoxine resistance. The present study was designed to reveal the origin(s) of sulfadoxine resistance in Cambodia and its evolutionary relationship to African and South American dhps alleles. We sequenced 234 Cambodian Plasmodium falciparum isolates for the dhps codons S436A/F, A437G, K540E, A581G and A613S/T implicated in sulfadoxine resistance. We also genotyped 10 microsatellite loci around dhps to determine the genetic backgrounds of various alleles and compared them with the backgrounds of alleles prevalent in Africa and South America. In addition to previously known highly-resistant triple mutant dhps alleles SGEGA and AGEAA (codons 436, 437, 540, 581, 613 are sequentially indicated), a large proportion of the isolates (19.3%) contained a 540N mutation in association with 437G/581G yielding a previously unreported triple mutant allele, SGNGA. Microsatellite data strongly suggest the strength of selection was greater on triple mutant dhps alleles followed by the double and single mutants. We provide evidence for at least three independent origins for the double mutants, one each for the SGKGA, AGKAA and SGEAA alleles. Our data suggest that the triple mutant allele SGEGA and the novel allele SGNGA have common origin on the SGKGA background, whereas the AGEAA triple mutant was derived from AGKAA on multiple, albeit limited, genetic backgrounds. The SGEAA did not share haplotypes with any of the triple mutants. Comparative analysis of the microsatellite haplotypes flanking dhps alleles from Cambodia, Kenya, Cameroon and Venezuela revealed an independent origin of sulfadoxine resistant alleles in each of these regions. Widespread resistance to chloroquine (CQ) and sulfadoxine-pyrimethamine (SP), the two least expensive and widely available antimalarial drugs, has become a major global public health challenge. It is known that point mutations in Plasmodium falciparum crt, dhfr and dhps genes contribute to resistance to CQ, pyrimethamine and sulfadoxine, respectively. CQ and pyrimethamine resistance spread to Africa and Asia from a few founding mutant lineages originating from the Thailand-Cambodia border. Here, we define the origins of dhps alleles in Cambodia and their relationships to African and South American counterparts. Three different triple mutant alleles including a novel allele comprised of 437G, 540N, and 581G mutations (S436G437N540G581A613) were found in Cambodia as opposed to a single triple mutant allele in South America and two common double mutant alleles in Africa. Microsatellite data suggest strong selection operating on triple mutant alleles as compared to double and single mutants in Cambodia. We report three major independent origins for the double mutants and at least two independent origins for the highly resistant triple mutant dhps alleles in Cambodia. We also show that the resistant dhps alleles in Africa and South America have distinct origins from Cambodia. These results suggest that the evolution and spread of sulfadoxine resistance is different from CQ and pyrimethamine resistance.
Collapse
Affiliation(s)
- Sumiti Vinayak
- Atlanta Research and Education Foundation, Atlanta, Georgia, United States of America
- Malaria Branch, Division of Parasitic Diseases, National Center for Zoonotic Vector Borne and Enteric Diseases, Coordinating Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Md Tauqeer Alam
- Malaria Branch, Division of Parasitic Diseases, National Center for Zoonotic Vector Borne and Enteric Diseases, Coordinating Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Tonya Mixson-Hayden
- Malaria Branch, Division of Parasitic Diseases, National Center for Zoonotic Vector Borne and Enteric Diseases, Coordinating Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Andrea M. McCollum
- Malaria Branch, Division of Parasitic Diseases, National Center for Zoonotic Vector Borne and Enteric Diseases, Coordinating Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Rithy Sem
- National Malaria Center, Phnom Penh, Cambodia
- US Naval Medical Research Unit No. 2, Jakarta, Indonesia
| | - Naman K. Shah
- Department of Epidemiology, UNC School of Public Health, Chapel Hill, North Carolina, United States of America
| | - Pharath Lim
- Institut Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Sinuon Muth
- National Malaria Center, Phnom Penh, Cambodia
| | | | - Thierry Fandeur
- Institut Pasteur, Unité d'Immunologie Moléculaire des Parasites, Paris, France
| | - John W. Barnwell
- Malaria Branch, Division of Parasitic Diseases, National Center for Zoonotic Vector Borne and Enteric Diseases, Coordinating Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Ananias A. Escalante
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | | | | | - Steven R. Meshnick
- Department of Epidemiology, UNC School of Public Health, Chapel Hill, North Carolina, United States of America
| | - Venkatachalam Udhayakumar
- Malaria Branch, Division of Parasitic Diseases, National Center for Zoonotic Vector Borne and Enteric Diseases, Coordinating Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- * E-mail:
| |
Collapse
|
21
|
Juliano JJ, Ariey F, Sem R, Tangpukdee N, Krudsood S, Olson C, Looareesuwan S, Rogers WO, Wongsrichanalai C, Meshnick SR. Misclassification of drug failure in Plasmodium falciparum clinical trials in southeast Asia. J Infect Dis 2009; 200:624-8. [PMID: 19591576 DOI: 10.1086/600892] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Most trials of antimalarials occur in areas in which reinfections are possible. For Plasmodium falciparum, reinfections are distinguished from recrudescences by polymerase chain reaction analysis of 3 polymorphic genes. However, the validity of this approach has never been rigorously tested. We tested for misclassification in 6 patients from clinical trials in Thailand and Cambodia who were classified as being reinfected by the standard polymerase chain reaction protocol. Using heteroduplex tracking assays and direct DNA sequencing, we found that 5 (83%) of 6 patients were misclassified. Misclassification in this manner overestimates the efficacy of antimalarials and delays the recognition of decreasing therapeutic efficacy, thus delaying potential changes in policy.
Collapse
Affiliation(s)
- Jonathan J Juliano
- Division of Infectious Diseases, School of Medicine, Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27599, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Rogers WO, Sem R, Tero T, Chim P, Lim P, Muth S, Socheat D, Ariey F, Wongsrichanalai C. Failure of artesunate-mefloquine combination therapy for uncomplicated Plasmodium falciparum malaria in southern Cambodia. Malar J 2009; 8:10. [PMID: 19138388 PMCID: PMC2628668 DOI: 10.1186/1475-2875-8-10] [Citation(s) in RCA: 157] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 01/12/2009] [Indexed: 11/10/2022] Open
Abstract
Background Resistance to anti-malarial drugs hampers control efforts and increases the risk of morbidity and mortality from malaria. The efficacy of standard therapies for uncomplicated Plasmodium falciparum and Plasmodium vivax malaria was assessed in Chumkiri, Kampot Province, Cambodia. Methods One hundred fifty-one subjects with uncomplicated falciparum malaria received directly observed therapy with 12 mg/kg artesunate (over three days) and 25 mg/kg mefloquine, up to a maximum dose of 600 mg artesunate/1,000 mg mefloquine. One hundred nine subjects with uncomplicated vivax malaria received a total of 25 mg/kg chloroquine, up to a maximum dose of 1,500 mg, over three days. Subjects were followed for 42 days or until recurrent parasitaemia was observed. For P. falciparum infected subjects, PCR genotyping of msp1, msp2, and glurp was used to distinguish treatment failures from new infections. Treatment failure rates at days 28 and 42 were analyzed using both per protocol and Kaplan-Meier survival analysis. Real Time PCR was used to measure the copy number of the pfmdr1 gene and standard 48-hour isotopic hypoxanthine incorporation assays were used to measure IC50 for anti-malarial drugs. Results Among P. falciparum infected subjects, 47.0% were still parasitemic on day 2 and 11.3% on day 3. The PCR corrected treatment failure rates determined by survival analysis at 28 and 42 days were 13.1% and 18.8%, respectively. Treatment failure was associated with increased pfmdr1 copy number, higher initial parasitaemia, higher mefloquine IC50, and longer time to parasite clearance. One P. falciparum isolate, from a treatment failure, had markedly elevated IC50 for both mefloquine (130 nM) and artesunate (6.7 nM). Among P. vivax infected subjects, 42.1% suffered recurrent P. vivax parasitaemia. None acquired new P. falciparum infection. Conclusion The results suggest that artesunate-mefloquine combination therapy is beginning to fail in southern Cambodia and that resistance is not confined to the provinces at the Thai-Cambodian border. It is unclear whether the treatment failures are due solely to mefloquine resistance or to artesunate resistance as well. The findings of delayed clearance times and elevated artesunate IC50 suggest that artesunate resistance may be emerging on a background of mefloquine resistance.
Collapse
Affiliation(s)
- William O Rogers
- Naval Medical Research Unit #2, Komp, P2P/PLP-LITBANGKES, Jl, Percetakan Negara No, 29, Jakarta 10560, Indonesia.
| | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Lim P, Alker AP, Khim N, Shah NK, Incardona S, Doung S, Yi P, Bouth DM, Bouchier C, Puijalon OM, Meshnick SR, Wongsrichanalai C, Fandeur T, Le Bras J, Ringwald P, Ariey F. Pfmdr1 copy number and arteminisin derivatives combination therapy failure in falciparum malaria in Cambodia. Malar J 2009; 8:11. [PMID: 19138391 PMCID: PMC2627910 DOI: 10.1186/1475-2875-8-11] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Accepted: 01/12/2009] [Indexed: 12/02/2022] Open
Abstract
Background The combination of artesunate and mefloquine was introduced as the national first-line treatment for Plasmodium falciparum malaria in Cambodia in 2000. However, recent clinical trials performed at the Thai-Cambodian border have pointed to the declining efficacy of both artesunate-mefloquine and artemether-lumefantrine. Since pfmdr1 modulates susceptibility to mefloquine and artemisinin derivatives, the aim of this study was to assess the link between pfmdr1 copy number, in vitro susceptibility to individual drugs and treatment failure to combination therapy. Methods Blood samples were collected from P. falciparum-infected patients enrolled in two in vivo efficacy studies in north-western Cambodia: 135 patients were treated with artemether-lumefantrine (AL group) in Sampovloun in 2002 and 2003, and 140 patients with artesunate-mefloquine (AM group) in Sampovloun and Veal Veng in 2003 and 2004. At enrollment, the in vitro IC50 was tested and the strains were genotyped for pfmdr1 copy number by real-time PCR. Results The pfmdr1 copy number was analysed for 115 isolates in the AM group, and for 109 isolates in the AL group. Parasites with increased pfmdr1 copy number had significantly reduced in vitro susceptibility to mefloquine, lumefantrine and artesunate. There was no association between pfmdr1 polymorphisms and in vitro susceptibilities. In the patients treated with AM, the mean pfmdr1copy number was lower in subjects with adequate clinical and parasitological response compared to those who experienced late treatment failure (n = 112, p < 0.001). This was not observed in the patients treated with AL (n = 96, p = 0.364). The presence of three or more copies of pfmdr1 were associated with recrudescence in artesunate-mefloquine treated patients (hazard ratio (HR) = 7.80 [95%CI: 2.09–29.10], N = 115), p = 0.002) but not with recrudescence in artemether-lumefantrine treated patients (HR = 1.03 [95%CI: 0.24–4.44], N = 109, p = 0.969). Conclusion This study shows that pfmdr1 copy number is a molecular marker of AM treatment failure in falciparum malaria on the Thai-Cambodian border. However, while it is associated with increased IC50 for lumefantrine, pfmdr1 copy number is not associated with AL treatment failure in the area, suggesting involvement of other molecular mechanisms in AL treatment failures in Cambodia.
Collapse
Affiliation(s)
- Pharath Lim
- Institut Pasteur in Cambodia, Phnom Penh, Cambodia.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Shah NK, Alker AP, Sem R, Susanti AI, Muth S, Maguire JD, Duong S, Ariey F, Meshnick SR, Wongsrichanalai C. Molecular surveillance for multidrug-resistant Plasmodium falciparum, Cambodia. Emerg Infect Dis 2008; 14:1637-40. [PMID: 18826834 PMCID: PMC2609877 DOI: 10.3201/eid1410.080080] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We conducted surveillance for multidrug-resistant Plasmodium falciparum in Cambodia during 2004–2006 by assessing molecular changes in pfmdr1. The high prevalence of isolates with multiple pfmdr1 copies found in western Cambodia near the Thai border, where artesunate–mefloquine therapy failures occur, contrasts with isolates from eastern Cambodia, where this combination therapy remains highly effective.
Collapse
Affiliation(s)
- Naman K Shah
- University of North Carolina School of Public Health, Chapel Hill, North Carolina, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Banoo S, Bell D, Bossuyt P, Herring A, Mabey D, Poole F, Smith PG, Sriram N, Wongsrichanalai C, Linke R, O'Brien R, Perkins M, Cunningham J, Matsoso P, Nathanson CM, Olliaro P, Peeling RW, Ramsay A. Evaluation of diagnostic tests for infectious diseases: general principles. Nat Rev Microbiol 2008. [DOI: 10.1038/nrmicro1523y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
|
26
|
Banoo S, Bell D, Bossuyt P, Herring A, Mabey D, Poole F, Smith PG, Sriram N, Wongsrichanalai C, Linke R, O'Brien R, Perkins M. Evaluation of diagnostic tests for infectious diseases: general principles. Nat Rev Microbiol 2008; 6:S16-S26. [PMID: 22745954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
|
27
|
Abstract
Resistance to many antimalaria drugs developed on the Cambodia-Thailand border long before developing elsewhere. Because antimalaria resistance is now a global problem, artemisinin-based combination therapies (ACTs) are the first-line therapies in most malaria-endemic countries. However, recent clinical and molecular studies suggest the emergence of ACT-resistant Plasmodium falciparum infections in the Cambodia-Thailand border area, where standard ACT is artesunate and mefloquine. These ACT failures might be caused by high-level mefloquine resistance because mefloquine was used for monotherapy long before the introduction of ACT. This observation raises 2 questions. First, how can existing P. falciparum-resistant strains be controlled? Second, how can the evolution of new ACT- resistant strains be avoided elsewhere, e.g., in Africa? Enforcement of rational drug use and improved diagnostic capacity are among the measures needed to avoid and contain ACT resistance.
Collapse
|
28
|
Wongsrichanalai C, Barcus MJ, Muth S, Sutamihardja A, Wernsdorfer WH. A review of malaria diagnostic tools: microscopy and rapid diagnostic test (RDT). Am J Trop Med Hyg 2007; 77:119-127. [PMID: 18165483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
The absolute necessity for rational therapy in the face of rampant drug resistance places increasing importance on the accuracy of malaria diagnosis. Giemsa microscopy and rapid diagnostic tests (RDTs) represent the two diagnostics most likely to have the largest impact on malaria control today. These two methods, each with characteristic strengths and limitations, together represent the best hope for accurate diagnosis as a key component of successful malaria control. This review addresses the quality issues with current malaria diagnostics and presents data from recent rapid diagnostic test trials. Reduction of malaria morbidity and drug resistance intensity plus the associated economic loss of these two factors require urgent scaling up of the quality of parasite-based diagnostic methods. An investment in anti-malarial drug development or malaria vaccine development should be accompanied by a parallel commitment to improve diagnostic tools and their availability to people living in malarious areas.
Collapse
Affiliation(s)
- Chansuda Wongsrichanalai
- U.S. Naval Medical Research Unit No. 2 (NAMRU-2), Jalan Percetakan Negara No. 29, Jakarta, Republic of Indonesia.
| | | | | | | | | |
Collapse
|
29
|
Wongsrichanalai C, Wernsdorfer WH, Muth S, Sutamihardja A, Barcus MJ. A Review of Malaria Diagnostic Tools: Microscopy and Rapid Diagnostic Test (RDT). Am J Trop Med Hyg 2007. [DOI: 10.4269/ajtmh.2007.77.119] [Citation(s) in RCA: 548] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
30
|
Bacon DJ, Jambou R, Fandeur T, Le Bras J, Wongsrichanalai C, Fukuda MM, Ringwald P, Sibley CH, Kyle DE. World Antimalarial Resistance Network (WARN) II: in vitro antimalarial drug susceptibility. Malar J 2007; 6:120. [PMID: 17822533 PMCID: PMC2008206 DOI: 10.1186/1475-2875-6-120] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2007] [Accepted: 09/06/2007] [Indexed: 11/16/2022] Open
Abstract
Intrinsic resistance of Plasmodium falciparum is clearly a major determinant of the clinical failure of antimalarial drugs. However, complex interactions between the host, the parasite and the drug obscure the ability to define parasite drug resistance in vivo. The in vitro antimalarial drug susceptibility assay determines ex-vivo growth of parasite in the presence of serial drug concentrations and, thus, eliminates host effects, such as drug metabolism and immunity. Although the sensitivity of the parasite to various antimalarials provided by such a test provides an important indicator of intrinsic parasite susceptibility, there are fundamental methodological issues that undermine comparison of in vitro susceptibility both between laboratories and within a single laboratory over time. A network of laboratories is proposed that will agree on the basic parameters of the in vitro test and associated measures of quality control. The aim of the network would be to establish baseline values of sensitivity to commonly used antimalarial agents from key regions of the world, and create a global database, linked to clinical, molecular and pharmacology databases, to support active surveillance to monitor temporal trends in parasite susceptibility. Such a network would facilitate the rapid detection of strains with novel antimalarial resistance profiles and investigate suitable alternative treatments with retained efficacy.
Collapse
Affiliation(s)
- David J Bacon
- Parasitology Program, Naval Medical Research Center Detachment, Lima, Peru
| | - Ronan Jambou
- Laboratoire d'immunologie Clinique et Parasitaire, Institut Pasteur, Dakar
| | - Thierry Fandeur
- Unité d'Immunologie Moléculaire des Parasites, Institut Pasteur, Paris, France
| | | | | | - Mark M Fukuda
- Department of Immunology and Medicine, United States Army Medical Component, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Pascal Ringwald
- Global Malaria Programme, World Health Organization, 20 Av. Appia, 1211 Geneva 27, Switzerland
| | | | - Dennis E Kyle
- Department of Global Health, College of Public Health, University of South Florida, Tampa, FL, USA
| |
Collapse
|
31
|
Banoo S, Bell D, Bossuyt P, Herring A, Mabey D, Poole F, Smith PG, Sriram N, Wongsrichanalai C, Linke R, O'Brien R, Perkins M, Cunningham J, Matsoso P, Nathanson CM, Olliaro P, Peeling RW, Ramsay A. Evaluation of diagnostic tests for infectious diseases: general principles. Nat Rev Microbiol 2007; 4:S20-32. [PMID: 17366684 DOI: 10.1038/nrmicro1570] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Shabir Banoo
- Medicines Control Council of South Africa, Pretoria, South Africa
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Alker AP, Lim P, Sem R, Shah NK, Yi P, Bouth DM, Tsuyuoka R, Maguire JD, Fandeur T, Ariey F, Wongsrichanalai C, Meshnick SR. Pfmdr1 and in vivo resistance to artesunate-mefloquine in falciparum malaria on the Cambodian-Thai border. Am J Trop Med Hyg 2007; 76:641-7. [PMID: 17426163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023] Open
Abstract
Artemisinin combination therapies (ACTs) have recently been adopted as first-line therapy for Plasmodium falciparum infections in most malaria-endemic countries. In this study, we estimated the association between artesunate-mefloquine therapy failure and genetic changes in the putative transporter, pfmdr1. Blood samples were acquired from 80 patients enrolled in an 2004 in vivo efficacy study in Pailin, Cambodia, and genotyped for pfmdr1 copy number and haplotype. Having parasites with three or more copies of pfmdr1 before treatment was strongly associated with recrudescence (hazard ratio [HR] = 8.30; 95% CI: 2.60-26.43). This relationship was maintained when controlling for initial parasite density and hematocrit (HR = 7.91; 95% CI: 2.38-26.29). Artesunate-mefloquine treatment selected for increased pfmdr1 copy number, because isolates from recurrent episodes had higher copy numbers than the paired enrollment samples (Wilcoxon rank test, P = 0.040). pfmdr1 copy number should be evaluated further as a surveillance tool for artesunate-mefloquine resistance in Cambodia.
Collapse
Affiliation(s)
- Alisa P Alker
- Department of Epidemiology, UNC School of Public Health, Chapel Hill, North Carolina 27599, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Mckenzie FE, Wongsrichanalai C, Magill AJ, Forney JR, Permpanich B, Lucas C, Erhart LM, O'Meara WP, Smith DL, Sirichaisinthop J, Gasser RA. Gametocytemia in Plasmodium vivax and Plasmodium falciparum infections. J Parasitol 2007; 92:1281-5. [PMID: 17304807 PMCID: PMC2500222 DOI: 10.1645/ge-911r.1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Two expert research microscopists, each blinded to the other's reports, diagnosed single-species malaria infections in 2,141 adults presenting at outpatient malaria clinics in Tak Province, Thailand, and Iquitos, Peru, in May-August 1998, May-July 1999, and May-June 2001. Plasmodium vivax patients with gametocytemia had higher fever and higher parasitemia than those without gametocytemia; temperature correlated with parasitemia in the patients with gametocytemia. Plasmodium falciparum patients with gametocytemia had lower fever than those without gametocytemia, but similar parasitemia; temperature correlated with parasitemia in the patients without gametocytemia. Hematologic data in Thailand in 2001 showed lower platelet counts in P. vivax patients with gametocytemia than in the P. vivax patients without gametocytemia, whereas P. falciparum patients with gametocytemia had similar platelet counts but lower red blood cell counts, hemoglobin levels, hematocrit levels, and higher lymphocyte counts than patients without gametocytemia.
Collapse
Affiliation(s)
- F Ellis Mckenzie
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland 20892, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
O'Meara WP, Barcus M, Wongsrichanalai C, Muth S, Maguire JD, Jordan RG, Prescott WR, McKenzie FE. Reader technique as a source of variability in determining malaria parasite density by microscopy. Malar J 2006; 5:118. [PMID: 17164007 PMCID: PMC1712346 DOI: 10.1186/1475-2875-5-118] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Accepted: 12/12/2006] [Indexed: 12/01/2022] Open
Abstract
Background Accurate identification and quantification of malaria parasites are critical for measuring clinical trial outcomes. Positive and negative diagnosis is usually sufficient for the assessment of therapeutic outcome, but vaccine or prophylactic drug trials require measuring density of infection as a primary endpoint. Microscopy is the most established and widely-used technique for quantifying parasite densities in the blood. Methods Results obtained by 24–27 expert malaria microscopists, who had independently read 895 slides from 35 donors, were analysed to understand how reader technique contributes to discrepancy in measurements of parasite density over a wide range of densities. Results Among these 35 donations, standard deviations ranged from 30% to 250% of the mean parasite density and the percent discrepancy was inversely correlated with the mean parasite density. The number of white blood cells indexed and whether parasites were counted in the thick film or thin film were shown to significantly contribute to discrepancy amongst microscopists. Conclusion Errors in microscopy measurements are not widely appreciated or addressed but have serious consequences for efficacy trials, including possibly abandoning promising vaccine candidates.
Collapse
Affiliation(s)
- Wendy Prudhomme O'Meara
- Division of International Epidemiology and Population Studies, Fogarty International Center, National Institutes of Health, 16 Center Dr., Building 16, Bethesda MD 20892, USA
| | | | | | - Sinuon Muth
- National Center for Parasitology, Entomology and Malaria Control (CNM), Ministry of Health, Phnom Penh, Cambodia
| | | | | | | | | |
Collapse
|
35
|
Vijaykadga S, Rojanawatsiriwej C, Ariey F, Meshnick SR, Wongsrichanalai C. Letters to the editors. Trop Med Int Health 2006. [DOI: 10.1111/j.1365-3156.2006.01749_2.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
36
|
Banoo S, Bell D, Bossuyt P, Herring A, Mabey D, Poole F, Smith PG, Sriram N, Wongsrichanalai C, Linke R, O'Brien R, Perkins M, Cunningham J, Matsoso P, Nathanson CM, Olliaro P, Peeling RW, Ramsay A. Evaluation of diagnostic tests for infectious diseases: general principles. Nat Rev Microbiol 2006; 4:S21-31. [PMID: 17034069 DOI: 10.1038/nrmicro1523] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
37
|
Maguire JD, Lederman ER, Barcus MJ, O'Meara WAP, Jordon RG, Duong S, Muth S, Sismadi P, Bangs MJ, Prescott WR, Baird JK, Wongsrichanalai C. Production and validation of durable, high quality standardized malaria microscopy slides for teaching, testing and quality assurance during an era of declining diagnostic proficiency. Malar J 2006; 5:92. [PMID: 17062168 PMCID: PMC1634857 DOI: 10.1186/1475-2875-5-92] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2006] [Accepted: 10/25/2006] [Indexed: 11/18/2022] Open
Abstract
Background Sets of Giemsa-stained, blood smear slides with systematically verified composite diagnoses would contribute substantially to development of externally validated quality assurance systems for the microscopic diagnosis of malaria. Methods whole blood from Plasmodium-positive donors in Cambodia and Indonesia and individuals with no history of risk for malaria was collected. Using standard operating procedures, technicians prepared Giemsa-stained thick and thin smears from each donor. One slide from each of the first 35 donations was distributed to each of 28 individuals acknowledged by reputation as having expertise in the microscopic diagnosis of malaria. These reference readers recorded presence or absence of Plasmodium species and parasite density. A composite diagnosis for each donation was determined based on microscopic findings and species-specific small subunit ribosomal RNA (ssrRNA) DNA polymerase chain reaction (PCR) amplification. Results More than 12, 000 slides were generated from 124 donations. Reference readers correctly identified presence of parasites on 85% of slides with densities <100 parasites/μl, which improved to 100% for densities >350 parasites/μl. Percentages of agreement with composite diagnoses were highest for Plasmodium falciparum (99%), followed by Plasmodium vivax (86%). Conclusion Herein, a standardized method for producing large numbers of consistently high quality, durable Giemsa-stained blood smears and validating composite diagnoses for the purpose of creating a malaria slide repository in support of initiatives to improve training and competency assessment amidst a background of variability in diagnosis is described.
Collapse
Affiliation(s)
- Jason D Maguire
- U.S. Naval Medical Research Unit No.2 (NAMRU-2), Jakarta, Indonesia
- Naval Medical Center Portsmouth, 620 John Paul Jones Circle, Portsmouth, Virginia 23708-2197, USA
| | - Edith R Lederman
- U.S. Naval Medical Research Unit No.2 (NAMRU-2), Jakarta, Indonesia
| | | | | | | | - Socheat Duong
- National Center for Parasitology, Entomology and Malaria Control (CNM), Phnom Penh, Cambodia
| | - Sinuon Muth
- National Center for Parasitology, Entomology and Malaria Control (CNM), Phnom Penh, Cambodia
| | - Priyanto Sismadi
- National Institute of Health Research and Development, Ministry of Health, Jakarta, Indonesia
| | - Michael J Bangs
- U.S. Naval Medical Research Unit No.2 (NAMRU-2), Jakarta, Indonesia
| | | | - J Kevin Baird
- U.S. Naval Medical Research Unit No.2 (NAMRU-2), Jakarta, Indonesia
| | | |
Collapse
|
38
|
Abstract
The replacement of conventional antimalarial drugs with high-cost, artemisinin-based alternatives has created a gap in the successful management of malaria. This gap reflects an increased need for accurate disease diagnosis that cannot be met by traditional microscopy techniques. The recent introduction of rapid diagnostic tests (RDTs) has the potential to meet this need, but successful RDT implementation has been curtailed by poor product performance, inadequate methods to determine the quality of products and a lack of emphasis and capacity to deal with these issues. Economics and a desire for improved case management will result in the rapid growth of RDT use in the coming years. However, for their potential to be realized, it is crucial that high-quality RDT products that perform reliably and accurately under field conditions are made available. In achieving this goal, the shift from symptom-based diagnosis to parasite-based management of malaria can bring significant improvements to tropical fever management, rather than represent a further burden on poor, malaria-endemic populations and their overstretched health services.
Collapse
Affiliation(s)
- David Bell
- Malaria, and other Vector-borne and Parasitic Diseases, World Health Organization Regional Office for the Western Pacific, P.O. Box 2932, Manila, Philippines.
| | | | | |
Collapse
|
39
|
Ibrahim IN, Winoto I, Wongsrichanalai C, Blair P, Stoops C. Abundance and distribution of Xenopsylla cheopis on small mammals collected in West Java, Indonesia during rodent-borne disease surveys. Southeast Asian J Trop Med Public Health 2006; 37:932-6. [PMID: 17333735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
During February 2004 and September 2005, Xenopsylla cheopis were collected from small mammal hosts during rodent-bone disease surveys in Jakarta and Bandung, Indonesia. During 4 trap nights in Jakarta, 4 rodent species (Rattus exulans, Rattus norvegicus, Rattus tanezumi and Mus musculus) and one shrew species (Suncus murinus) were collected. Rattus tanezumi had the highest X. cheopis load (128 X. cheopis from 84 R. tanezumi) but R. norvegicus had the highest flea index, 1.8. In Bandung, over 6 trap nights 3 rodent species were collected (R. norvegicus, R. tanezumi and M. musculus) and the shrew, S. murinus, were collected. Rattus norvegicus had the highest number of X. cheopis collected (407 X. cheopis from 181 R. norvegicus) but R. tanezumi had the highest flea index, 3.5. During both surveys, X. cheopis was the species of flea collected.
Collapse
Affiliation(s)
- Ima Nurisa Ibrahim
- Ecology and Health Status Research and Development Center, National Institute of Health Research and Development, Ministry of Health, Jakarta, Indonesia
| | | | | | | | | |
Collapse
|
40
|
Abstract
The replacement of conventional antimalarial drugs with high-cost, artemisinin-based alternatives has created a gap in the successful management of malaria. This gap reflects an increased need for accurate disease diagnosis that cannot be met by traditional microscopy techniques. The recent introduction of rapid diagnostic tests (RDTs) has the potential to meet this need, but successful RDT implementation has been curtailed by poor product performance, inadequate methods to determine the quality of products and a lack of emphasis and capacity to deal with these issues. Economics and a desire for improved case management will result in the rapid growth of RDT use in the coming years. However, for their potential to be realized, it is crucial that high-quality RDT products that perform reliably and accurately under field conditions are made available. In achieving this goal, the shift from symptom-based diagnosis to parasite-based management of malaria can bring significant improvements to tropical fever management, rather than represent a further burden on poor, malaria-endemic populations and their overstretched health services.
Collapse
Affiliation(s)
- David Bell
- Malaria, other Vector-borne and Parasitic Diseases, World Health Organization-Regional Office for the Western Pacific, P.O. Box 2932, Manila, Philippines.
| | | | | |
Collapse
|
41
|
Abstract
The replacement of conventional antimalarial drugs with high-cost, artemisinin-based alternatives has created a gap in the successful management of malaria. This gap reflects an increased need for accurate disease diagnosis that cannot be met by traditional microscopy techniques. The recent introduction of rapid diagnostic tests (RDTs) has the potential to meet this need, but successful RDT implementation has been curtailed by poor product performance, inadequate methods to determine the quality of products and a lack of emphasis and capacity to deal with these issues. Economics and a desire for improved case management will result in the rapid growth of RDT use in the coming years. However, for their potential to be realized, it is crucial that high-quality RDT products that perform reliably and accurately under field conditions are made available. In achieving this goal, the shift from symptom-based diagnosis to parasite-based management of malaria can bring significant improvements to tropical fever management, rather than represent a further burden on poor, malaria-endemic populations and their overstretched health services.
Collapse
Affiliation(s)
- David Bell
- Malaria, and other Vector-borne and Parasitic Diseases, World Health Organization Regional Office for the Western Pacific, P.O. Box 2932, Manila, Philippines.
| | | | | |
Collapse
|
42
|
McKenzie FE, Smith DL, O'Meara WP, Forney JR, Magill AJ, Permpanich B, Erhart LM, Sirichaisinthop J, Wongsrichanalai C, Gasser RA. Fever in patients with mixed-species malaria. Clin Infect Dis 2006; 42:1713-8. [PMID: 16705577 PMCID: PMC2481387 DOI: 10.1086/504330] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Accepted: 02/16/2006] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Clinical symptoms of mixed-species malaria infections have been variously reported as both less severe and more severe than those of single-species infections. METHODS Oral temperatures were taken from and blood slides were prepared for 2308 adults who presented at outpatient malaria clinics in Tak Province (Thailand) during May-August 1998, May-July 1999, and May-June 2001 with malaria infections diagnosed by 2 expert research microscopists, each of whom was blinded to the other's reports. RESULTS In each year, temperatures of patients with mixed Plasmodium vivax-Plasmodium falciparum infections were higher than temperatures of patients with P. vivax or P. falciparum infections. In every mixed-species case, P. falciparum parasitemia was higher than P. vivax parasitemia, but patient temperature was not correlated with the parasitemia of either species or with the total parasitemia. CONCLUSIONS Among adults who self-report to malaria clinics in western Thailand, patients with mixed P. vivax-P. falciparum infections have higher fevers than patients with single-species infections, a distinction that cannot be attributed to differences in parasitemia. This observation warrants more detailed investigations, spanning wider ranges of ages and transmission environments.
Collapse
Affiliation(s)
- F Ellis McKenzie
- Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Miller RS, Wongsrichanalai C, Buathong N, McDaniel P, Walsh DS, Knirsch C, Ohrt C. Effective treatment of uncomplicated Plasmodium falciparum malaria with azithromycin-quinine combinations: a randomized, dose-ranging study. Am J Trop Med Hyg 2006; 74:401-6. [PMID: 16525097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023] Open
Abstract
Azithromycin, the most potent antimalarial macrolide antibiotic, is synergistic with quinine against Plasmodium falciparum in vitro. We assessed combinations of azithromycin and quinine against uncomplicated P. falciparum malaria at the Armed Forces Research Institute of Medical Sciences-Kwai River Clinical Center along the Thailand-Myanmar border, an area with a high prevalence of multidrug-resistant P. falciparum. Four regimens were assessed in an open-label dose-ranging design involving 61 volunteers. All received oral quinine (Q; 30 mg/kg/day divided every 8 hours for 3 days) with oral azithromycin (Az; 500 mg twice a day for 3 days, 500 mg twice a day for 5 days, or 500 mg three times a day for 3 days). A comparator group received quinine and doxycycline (Dx; 100 mg twice a day for 7 days). Study observation was 28 days per protocol. Sixty volunteers completed the study. Seven days of QDx cured 100% of the volunteers. One failure occurred in the lowest QAz regimen (on day 28) and none occurred in either of the two higher Az regimens. Cinchonism occurred in nearly all subjects. Overall, the azithromycin regimens were well tolerated, and no volunteers discontinued therapy. Three- and five-day azithromycin-quinine combination therapy appears safe, well tolerated, and effective in curing drug-resistant P. falciparum malaria. Further evaluation, especially in pediatric and obstetric populations, is warranted.
Collapse
Affiliation(s)
- R Scott Miller
- Department of Immunology and Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
| | | | | | | | | | | | | |
Collapse
|
44
|
Vijaykadga S, Rojanawatsirivej C, Cholpol S, Phoungmanee D, Nakavej A, Wongsrichanalai C. In vivo sensitivity monitoring of mefloquine monotherapy and artesunate-mefloquine combinations for the treatment of uncomplicated falciparum malaria in Thailand in 2003. Trop Med Int Health 2006; 11:211-9. [PMID: 16451346 DOI: 10.1111/j.1365-3156.2005.01557.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To monitor the efficacy of anti-malarial treatments in Thailand. METHOD A 28-day in vivo study in nine provinces along international borders in 2003. The first group comprised 164 patients from four provinces: Mae Hong Son, Chiang Mai, Ratchaburi and Ubon Ratchathani. These patients received 15 mg/kg mefloquine as a single dose. The second group, 58 patients from Kanchanaburi, were treated with 15 mg/kg mefloquine plus artesunate (12 mg/kg). The third group, 196 patients from provinces with high-level mefloquine resistance (Tak, Ranong, Chanthaburi and Trat), received 25 mg/kg of mefloquine plus 12 mg/kg artesunate. In all arms, follow-up blood smears were scheduled for days 1, 2, 3, 7, 14, 21 and 28. All patients tolerated the regimens well. RESULTS The percentage of adequate clinical and parasitological response to mefloquine monotherapy was 62.0% in Mae Hong Son, 75.0% in Chiang Mai, 94.0% in Ratchaburi and 89.7% in Ubon Ratchathani. In Kanchanaburi, the percentage of adequate clinical and parasitological response to the artesunate-mefloquine combination was 94.2%. In the third group, this response exceeded 90%, except in Trat, where it was only 78.6% (44 patients). CONCLUSION Mefloquine monotherapy must urgently be replaced in Mae Hong Son and Chiang Mai. The markedly reduced efficacy of the artesunate-mefloquine combination used in Trat raises questions about the future of this therapy on the southeastern border of Thailand with Cambodia. It is very worrying because no practical and affordable alternative is yet available.
Collapse
Affiliation(s)
- Saowanit Vijaykadga
- Disease Control Department, Ministry of Public Health, Nonthaburi, Thailand.
| | | | | | | | | | | |
Collapse
|
45
|
McKenzie F, O’Meara W, Wongsrichanalai C. Reply to Rodríguez‐Morales et al. J Infect Dis 2005. [DOI: 10.1086/496995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
|
46
|
Heppner DG, Walsh DS, Uthaimongkol N, Tang DB, Tulyayon S, Permpanich B, Wimonwattrawatee T, Chuanak N, Laoboonchai A, Sookto P, Brewer TG, McDaniel P, Eamsila C, Yongvanitchit K, Uhl K, Kyle DE, Keep LW, Miller RE, Wongsrichanalai C. Randomized, controlled, double-blind trial of daily oral azithromycin in adults for the prophylaxis of Plasmodium vivax malaria in Western Thailand. Am J Trop Med Hyg 2005; 73:842-9. [PMID: 16282291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
We assessed the prophylactic efficacy of azithromycin (250 mg/day) against malaria in 276 adults in western Thailand in a randomized, double-blind, placebo-controlled trial. After antimalarial suppressive treatment, volunteers were randomized in a 2:1 ratio to either the azithromycin or placebo, respectively. Study medication was given for an average of 74 days. The azithromycin group (n = 179) had five endpoint parasitemias (1 Plasmodium vivax and 4 P. falciparum), and the placebo group (n = 97) had 28 endpoint parasitemias (21 P. vivax, 5 P. falciparum, and 2 mixed infections). Adverse events and compliance and withdrawal rates were similar in both groups. The protective efficacy (PE) of azithromycin was 98% for P. vivax (95% confidence interval [CI] = 88-100%). There were too few cases to reliably estimate the efficacy of azithromycin for P. falciparum (PE =71%, 95% C =-14-94%). We conclude that daily azithromycin was safe, well-tolerated, and had a high efficacy for the prevention of P. vivax malaria.
Collapse
Affiliation(s)
- D Gray Heppner
- Department of Immunology and Medicine, United States Army Medical Component, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Winoto IL, Goethert H, Ibrahim IN, Yuniherlina I, Stoops C, Susanti I, Kania W, Maguire JD, Bangs MJ, Telford SR, Wongsrichanalai C. Bartonella species in rodents and shrews in the greater Jakarta area. Southeast Asian J Trop Med Public Health 2005; 36:1523-9. [PMID: 16610656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
In February 2004, we captured 221 rodents and shrews in the Greater Jakarta area as part of a study to determine the prevalence of rodent-associated vector-borne infections. Microscopic examination of blood smears revealed 6% (13/218) to be positive for Bartonella spp. The corresponding DNA samples, either from blood blots or frozen spleen pieces and from fleas collected on these animals, were tested for evidence of Bartonella infection by PCR, targeting the portions: 378bp and 930bp of the citrate synthase gene (g/tA). The sequences from our sample clusters with a Peruvian entity, B. phoceensis, B. rattimassiliensis and B. elizabethae, the latter species has been associated with endocarditis and neuroretinitis in humans. As previous analyses have shown, there appears to be little geographic or host consistency with phylogenetic placement. The public health significance of these findings remains to be determined.
Collapse
|
48
|
O'Meara WP, McKenzie FE, Magill AJ, Forney JR, Permpanich B, Lucas C, Gasser RA, Wongsrichanalai C. Sources of variability in determining malaria parasite density by microscopy. Am J Trop Med Hyg 2005; 73:593-8. [PMID: 16172488 PMCID: PMC2500224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023] Open
Abstract
Enumeration of parasites by microscopic examination of blood smears is the only method available for quantifying parasitemia in infected blood. However, the sources and scale of error inherent in this technique have not been systematically investigated. Here we use data collected in outpatient clinics in Peru and Thailand to elucidate important sources of variation in parasite density measurements. We show that discrepancies between readings from two independent microscopists and multiple readings from a single microscopist are inversely related to the density of the infection. We present an example of how differences in reader technique, specifically the number of white blood cells counted, can contribute to the differences between readings. We discuss the implications of this analysis for field studies and clinical trials.
Collapse
|
49
|
McKenzie FE, Prudhomme WA, Magill AJ, Forney JR, Permpanich B, Lucas C, Gasser RA, Wongsrichanalai C. White blood cell counts and malaria. J Infect Dis 2005; 192:323-30. [PMID: 15962228 PMCID: PMC2481386 DOI: 10.1086/431152] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Accepted: 02/17/2005] [Indexed: 11/03/2022] Open
Abstract
White blood cells (WBCs) were counted in 4697 individuals who presented to outpatient malaria clinics in Maesod, Tak Province, Thailand, and Iquitos, Peru, between 28 May and 28 August 1998 and between 17 May and 9 July 1999. At each site and in each year, WBC counts in the Plasmodium falciparum-infected patients were lower than those in the Plasmodium vivax-infected patients, which, in turn, were lower than those in the uninfected patients. In Thailand, one-sixth of the P. falciparum-infected patients had WBC counts of <4000 cells/microL. Leukopenia may confound population studies that estimate parasite densities on the basis of an assumed WBC count of 8000 cells/microL. For instance, in the present study, use of this conventional approach would have overestimated average asexual parasite densities in the P. falciparum-infected patients in Thailand by nearly one-third.
Collapse
Affiliation(s)
- F Ellis McKenzie
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland 20892, USA.
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Ngrenngarmlert W, Kwiek JJ, Kamwendo DD, Ritola K, Swanstrom R, Wongsrichanalai C, Miller RS, Ittarat W, Meshnick SR. Measuring allelic heterogeneity in Plasmodium falciparum by a heteroduplex tracking assay. Am J Trop Med Hyg 2005; 72:694-701. [PMID: 15964952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023] Open
Abstract
We developed a novel Plasmodium falciparum genotyping strategy based on the heteroduplex tracking assay (HTA) method commonly used to genotype viruses. Because it can detect both sequence and size polymorphisms, we hypothesized that HTA is more sensitive than current methods. To test this hypothesis, we compared the ability of HTA and a nested polymerase chain reaction (PCR) to detect genetic diversity in 17 Thai samples. The HTA detected more MSP1 sequence variants in eight isolates (47%), less sequence variants in three isolates (18%), and an equal number of sequence variants in six isolates (35%), suggesting that HTA is equal to or more sensitive than the nested PCR. This study is a proof of concept that HTA is a sensitive allelic discrimination method able to determine genetic diversity in P. falciparum and warrants its use in studies of antimalarial drug efficacy.
Collapse
Affiliation(s)
- Warunee Ngrenngarmlert
- Department of Clinical Microscopy, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | | | | | | | | | | | | | | | | |
Collapse
|