1
|
Sifuna PM, Mbinji M, Lucas TO, Onyango I, Akala HM, Waitumbi JN, Ogutu BR, Hutter JN, Otieno W. The Walter Reed Project, Kisumu Field Station: Impact of Research on Malaria Policy, Management, and Prevention. Am J Trop Med Hyg 2024; 110:1069-1079. [PMID: 38653233 PMCID: PMC11154051 DOI: 10.4269/ajtmh.23-0115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 02/16/2024] [Indexed: 04/25/2024] Open
Abstract
The Walter Reed Project is a collaboration between the Walter Reed Army Institute of Research of the United States Department of Defense and the Kenya Medical Research Institute. The Kisumu field station, comprising four campuses, has until recently been devoted primarily to research on malaria countermeasures. The Kombewa Clinical Research Center is dedicated to conducting regulated clinical trials of therapeutic and vaccine candidates in development. The center's robust population-based surveillance platform, along with an active community engagement strategy, guarantees consistent recruitment and retention of participants in clinical trials. The Malaria Diagnostic Center, backed by WHO-certified microscopists and a large malaria blood film collection, champions high-quality malaria diagnosis and strict quality assurance through standardized microscopy trainings. The Malaria Drug Resistance Laboratory leverages cutting-edge technology such as real-time Polymerase Chain Reaction (qPCR) to conduct comprehensive research on resistance markers and obtain information on drug efficacy. The laboratory has been working on validating artemisinin resistance markers and improving tracking methods for current and future antimalarial compounds. Finally, the Basic Science Laboratory employs advanced genomic technology to examine endpoints such as immunogenicity and genomic fingerprinting for candidate drugs and vaccine efficacy. Herein, we examine the site's significant contributions to malaria policy, management, and prevention practices in Kenya and around the world.
Collapse
Affiliation(s)
- Peter M Sifuna
- Kenya Medical Research Institute, Kisumu, Kenya
- U.S. Army Medical Research Directorate-Africa, Kisumu, Kenya
| | - Michal Mbinji
- Kenya Medical Research Institute, Kisumu, Kenya
- U.S. Army Medical Research Directorate-Africa, Kisumu, Kenya
| | - Tina O Lucas
- Kenya Medical Research Institute, Kisumu, Kenya
- U.S. Army Medical Research Directorate-Africa, Kisumu, Kenya
| | - Irene Onyango
- Kenya Medical Research Institute, Kisumu, Kenya
- U.S. Army Medical Research Directorate-Africa, Kisumu, Kenya
| | - Hoseah M Akala
- Kenya Medical Research Institute, Kisumu, Kenya
- U.S. Army Medical Research Directorate-Africa, Kisumu, Kenya
| | - John N Waitumbi
- Kenya Medical Research Institute, Kisumu, Kenya
- U.S. Army Medical Research Directorate-Africa, Kisumu, Kenya
| | - Bernhards R Ogutu
- Kenya Medical Research Institute, Kisumu, Kenya
- U.S. Army Medical Research Directorate-Africa, Kisumu, Kenya
| | - Jack N Hutter
- U.S. Army Medical Research Directorate-Africa, Kisumu, Kenya
| | - Walter Otieno
- Kenya Medical Research Institute, Kisumu, Kenya
- U.S. Army Medical Research Directorate-Africa, Kisumu, Kenya
| |
Collapse
|
2
|
Ikegbunam M, Maurer M, Abone H, Ezeagwuna D, Sandri TL, Esimone C, Ojurongbe O, Woldearegai TG, Kreidenweiss A, Held J, Fendel R. Evaluating Malaria Rapid Diagnostic Tests and Microscopy for Detecting Plasmodium Infection and Status of Plasmodium falciparum Histidine-Rich Protein 2/3 Gene Deletions in Southeastern Nigeria. Am J Trop Med Hyg 2024; 110:902-909. [PMID: 38531105 PMCID: PMC11066366 DOI: 10.4269/ajtmh.23-0690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 12/12/2023] [Indexed: 03/28/2024] Open
Abstract
Delays in malaria diagnosis increase treatment failures and deaths. In endemic regions, standard diagnostic methods are microscopy and malaria rapid diagnostic tests (mRDTs) detecting Plasmodium falciparum histidine-rich protein 2/3 (PFHRP2/PFHRP3), but gene deletions can allow certain parasites to remain undetected. We enlisted a cohort comprising 207 symptomatic individuals, encompassing both children and adults, at a hospital in Nnewi, Nigeria. The prevalence of parasites was determined using a highly sensitive, species-specific quantitative polymerase chain reaction (SS-qPCR). Within a subset of 132 participants, we assessed the sensitivity and specificity of microscopy and HRP2-mRDTs in comparison to SS-qPCR for the detection of P. falciparum. We also investigated the prevalence of pfhrp2/pfhrp3 gene deletions. Greater sensitivity was achieved with mRDTs (95%) compared with microscopy (77%). Also, mRDTs exhibited greater specificity (68%) than microscopy (44%). The positive predictive value of mRDTs (89%) surpassed that of microscopy (80%), suggesting a greater probability of accurately indicating the presence of infection. The negative predictive value of mRDTs (82%) was far greater than microscopy (39%). Of the 165 P. falciparum-positive samples screened for pfhrp2/pfhrp3 gene deletions, one gene deletion was detected in one sample. Regarding infection prevalence, 84% were positive for Plasmodium spp. (by reverse transcription [RT]-qPCR), with P. falciparum responsible for the majority (97%) of positive cases. Thus, exclusive reliance on microscopy in endemic areas may impede control efforts resulting from false negatives, underscoring the necessity for enhanced training and advocating for high-throughput molecular testing such as RT-qPCR or qPCR at referral centers to address limitations.
Collapse
Affiliation(s)
- Moses Ikegbunam
- Department of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Nigeria
- Molecular Research Foundation for Students and Scientist, Nnamdi Azikiwe University, Awka, Nigeria
| | - Maike Maurer
- Institute of Tropical Medicine, University of Tübingen, Germany
| | - Harrison Abone
- Department of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Nigeria
| | - Dorothy Ezeagwuna
- Departement of Parasitology and Entomology, Nnamdi Azikiwe University, Awka, Nigeria
| | - Thaisa Lucas Sandri
- Institute of Tropical Medicine, University of Tübingen, Germany
- Synovo GmbH, Tübingen, Germany
| | - Charles Esimone
- Department of Pharmaceutical Microbiology and Biotechnology, Nnamdi Azikiwe University, Awka, Nigeria
- Molecular Research Foundation for Students and Scientist, Nnamdi Azikiwe University, Awka, Nigeria
| | - Olusola Ojurongbe
- Department of Medical Microbiology & Parasitology, Ladoke Akintola University of Technology, Ogbomosho, Nigeria
| | - Tamirat Gebru Woldearegai
- Institute of Tropical Medicine, University of Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
| | - Andrea Kreidenweiss
- Institute of Tropical Medicine, University of Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
- Center de Recherches Médicales de Lambaréné (CERMEL), Gabon
| | - Jana Held
- Institute of Tropical Medicine, University of Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
- Center de Recherches Médicales de Lambaréné (CERMEL), Gabon
| | - Rolf Fendel
- Institute of Tropical Medicine, University of Tübingen, Germany
- German Center for Infection Research (DZIF), Tübingen, Germany
- Center de Recherches Médicales de Lambaréné (CERMEL), Gabon
| |
Collapse
|
3
|
Teou DC, Dorkenoo AM, Ataba E, Alidou S, Yakpa K, Abdou-Kerim A, Maman I, Agbonon A. Evaluation of the performance of advantage P.f. malaria Card ® and advantage malaria Pan + Pf Card ®, two rapid diagnostic tests for parasitological confirmation of malaria cases in field situation in Togo. Parasit Vectors 2023; 16:444. [PMID: 38037186 PMCID: PMC10691072 DOI: 10.1186/s13071-023-06062-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 11/16/2023] [Indexed: 12/02/2023] Open
Abstract
BACKGROUND In Togo, malaria remains a major public health problem, and the management of suspected cases requires confirmation with appropriate biological methods. Malaria diagnosis has been improved by the introduction of rapid diagnostic tests (RDTs), recommended by the World Health Organization (WHO) for areas where microscopy is not available. To be used, these RDTs must meet performance criteria defined by the WHO. This study was conducted to evaluate the diagnostic performance of two RDTs: Advantage P.f. Malaria Card® detecting HRP2 antigen and Advantage Malaria Pan + Pf Card® detecting both HRP2 and pLDH antigens. METHODS This was a cross-sectional analytical study conducted from December 2019 to February 2020 on malaria-suspected cases received in three sentinel sites in Togo and from whom capillary blood was collected to perform the two RDTs according to the manufacturer's instructions. Sensitivity and specificity were estimated by comparing to thick/thin blood smear, the gold standard, and to PCR, which is a more sensitive. RESULTS A total of 390 participants (54.9% female) with a median age of 18 (± 0.8) years were included in the study. The sensitivity of both Advantage P.f. Malaria Card® and Advantage Malaria Pan + Pf Card® compared to thick/thin blood smear was 91.8% and 91.3%, respectively, and for both the specificity was 94.7%. Compared to PCR, the sensitivity was 84.2% and 83.8%, respectively, and the specificity 96.5%. CONCLUSIONS The performances of the Advantage P.f. Malaria Card® and Advantage Malaria PAN + Pf Card® compared to microscopy, considered the gold standard, were acceptable under the field conditions found in Togo. They can therefore be used for the biological diagnosis of malaria.
Collapse
Affiliation(s)
- Diwaba Carmel Teou
- Faculté Des Sciences, Université de Lomé, Boulevard Eyadema, 01BP 1515, Lomé, Togo.
| | - Ameyo Monique Dorkenoo
- Faculté Des Sciences de La Santé, Université de Lomé, Boulevard Eyadema, 01BP 1515, Lomé, Togo
| | - Essoham Ataba
- Ministère de la Santé de L'Hygiène Publique et de L'Accès Universel Aux Soins, Programme National de Lutte Contre Le Paludisme, Quartier Administratif, 01BP 518, Lomé, Togo
| | - Smaila Alidou
- Département de Santé Publique, Unité de Formation et de Recherche en Sciences de la Santé, Université Joseph KI-ZERBO, Ouagadougou, Burkina Faso
| | - Kossi Yakpa
- Ministère de la Santé de L'Hygiène Publique et de L'Accès Universel Aux Soins, Programme National de Lutte Contre Le Paludisme, Quartier Administratif, 01BP 518, Lomé, Togo
| | - Agueregna Abdou-Kerim
- Ministère de la Santé de L'Hygiène Publique et de L'Accès Universel Aux Soins, Institut National d'Hygiène, Quartier Administratif, 01BP 1396, Lomé, Togo
| | - Issaka Maman
- Ministère de la Santé de L'Hygiène Publique et de L'Accès Universel Aux Soins, Institut National d'Hygiène, Quartier Administratif, 01BP 1396, Lomé, Togo
| | - Amegnona Agbonon
- Faculté Des Sciences, Université de Lomé, Boulevard Eyadema, 01BP 1515, Lomé, Togo
| |
Collapse
|
4
|
Hassanein RAM, Alkurbi MO, Alsobhi SH. Prevalence of Plasmodium species in Badr Governorate, Madinah Province, Saudi Arabia using microscopy and rapid diagnostic test. Medicine (Baltimore) 2023; 102:e35516. [PMID: 37861484 PMCID: PMC10589602 DOI: 10.1097/md.0000000000035516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 09/14/2023] [Indexed: 10/21/2023] Open
Abstract
Malaria infection still represents a notable public health risk in Saudi Arabia. This cross-sectional study aimed to determine the prevalence of Plasmodium species among clinically suspected cases who presented at Badr General Hospital and healthcare facilities in selected regions of Badr Governorate, Madinah Province, Saudi Arabia between January 2021 and January 2022. A total of 493 suspected patients were recruited from Badr Governorate, investigated for malaria infection using CBFME and rapid diagnostic test- CareStart Malaria Pf/PAN (HRP2/pLDH) Ag Combo rapid diagnostic tests. The results showed that malaria infection was 34 (6.89%) cases among 493 suspected patients using microscopic examination as reference test. Moreover, subjects aged 31 to 40 years and those aged 51 to 60 years had the highest (50%) and lowest (8.82%) percentages of malaria cases. Plasmodium vivax (19/34, 55.88%) was higher than P falciparum (15/34, 44.1%) as the causative agents of malaria cases. The majority of malaria cases (29/34, 80.9%) among non-Saudi mainly from Sudan (15/34, 44.1%), Pakistan (5/34, 14.7%), Bangladesh (5/34, 14.7%) and India (4/34, 11.76%) whereas malaria cases among Saudis (5/34, 14.7%). In addition, the majority of malaria cases (32/34, 94.11%) among male subjects while (2/34, 5.88%) among females. The current study revealed that malaria transmission is still active in Badr Governorate, Madinah Province, Saudi Arabia and represents a public health concern. Further screening implements and continuous epidemiological monitor of the status of malaria infection in Kingdom of Saudi Arabia are thus warranted to improve its controlling activities and eradicate malaria endemicity in the country.
Collapse
Affiliation(s)
- Raafat Abdel Moneim Hassanein
- Department of Laboratory Medicine, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah, Saudi Arabia
- Department of Zoonoses, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt
| | - Mohammed Othman Alkurbi
- Department of Laboratory Medicine, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Saad Hussain Alsobhi
- Department of Laboratory Medicine, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah, Saudi Arabia
- Badr General Hospital, Ministry of Health, Badr Governorate, Madinah Province, Saudi Arabia
| |
Collapse
|
5
|
Orimadegun AE, Dada-Adegbola HO, Michael OS, Adepoju AA, Funwei RI, Olusola FI, Ajayi IO, Ogunkunle OO, Ademowo OG, Jegede AS, Baba E, Hamade P, Webster J, Chandramohan D, Falade CO. SD-Bioline malaria rapid diagnostic test performance and time to become negative after treatment of malaria infection in Southwest Nigerian Children. Ann Afr Med 2023; 22:470-480. [PMID: 38358148 PMCID: PMC10775936 DOI: 10.4103/aam.aam_220_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 10/10/2022] [Accepted: 12/09/2022] [Indexed: 02/16/2024] Open
Abstract
Context and Aim Given the challenges of microscopy, we compared its performance with SD-Bioline malaria rapid diagnostic test (MRDT) and polymerase chain reaction (PCR) and evaluated the time it took for positive results to become negative after treatment of children with acute uncomplicated malaria. Subjects and Methods We present the report of 485 participants with complete MRDT, microscopy, and PCR data out of 511 febrile children aged 3-59 months who participated in a cohort study over a 12-month period in rural and urban areas of Ibadan, Nigeria. MRDT-positive children received antimalaria and tested at every visit over 28 days. Speciation was also carried out by PCR. Results With microscopy as the gold standard, SD-Bioline™ had 95.2% sensitivity, 66.4% specificity, 67.5% positive predictive value (PPV), and 94.9 negative predictive value (NPV), while with PCR the findings were 84.3% sensitivity, 66.5% specificity, 72.7% PPV, and 80.1% NPV. PCR speciation of malaria parasites revealed 91.6% Plasmodium falciparum, 18.9% Plasmodium malariae, and 4.4% Plasmodium ovale. Among the 47 children with P. malariae infections, 66.0% were coinfected with P. falciparum, while 54.6% cases of P. ovale occurred as coinfections with P. falciparum. The median time to a negative MRDT was 23.2 days, while the median time to a negative malaria microscopy was 3.8 days. The two survival curves were significantly different. Conclusions The SD-BiolineTM MRDT performed well, with remarkable persistence of rapid test-positive for an average of 23 days post treatment. The prevalence of P. malaria is somewhat greater than expected.
Collapse
Affiliation(s)
| | | | - Obaro S. Michael
- Department of Pharmacology and Therapeutics, College of Medicine, Ibadan, Nigeria
| | | | | | | | - IkeOluwapo O. Ajayi
- Department of Epidemiology and Biostatistics, College of Medicine, Ibadan, Nigeria
| | | | - Olusegun George Ademowo
- Department of Pharmacology and Therapeutics, College of Medicine, Ibadan, Nigeria
- Institute for Advanced Medical Research and Training, College of Medicine, Ibadan, Nigeria
| | - Ayodele Samuel Jegede
- Department of Sociology, Faculty of the Social Sciences, University of Ibadan, Ibadan, Nigeria
| | - Ebenezer Baba
- Malaria Consortium Regional Office for Africa, Kampala, Uganda
| | | | - Jayne Webster
- London School of Tropical Medicine and Hygiene, London, United Kingdom
| | | | - Catherine Olufunke Falade
- Department of Pharmacology and Therapeutics, College of Medicine, Ibadan, Nigeria
- Institute for Advanced Medical Research and Training, College of Medicine, Ibadan, Nigeria
| |
Collapse
|
6
|
Biruksew A, Demeke A, Birhanu Z, Kebede E, Golassa L, Mathebula EM, Yewhalaw D. Diagnostic performance of NxTek™ Eliminate Malaria-Pf test for the detection of Plasmodium falciparum in school children with asymptomatic malaria. Malar J 2023; 22:112. [PMID: 36991438 DOI: 10.1186/s12936-023-04529-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 03/13/2023] [Indexed: 03/30/2023] Open
Abstract
Abstract
Background
One of the major roadblocks to the falciparum malaria elimination programme is the presence of a portion of the population, such as school children, with asymptomatic malaria infection. Targeting such reservoirs of infections is critical to interrupting transmission and enhancing elimination efforts. The NxTek™ Eliminate Malaria Pf test is a highly sensitive rapid diagnostic test (hsRDT) for the detection of HRP-2. However, knowledge gaps exist in Ethiopia on the diagnostic performance of hsRDT for the detection of Plasmodium falciparum in school children with asymptomatic malaria.
Methods
A school-based cross-sectional study was conducted from September 2021 to January 2022 on 994 healthy school children (aged 6–15 years). Finger-pricked whole blood samples were collected for microscopy, hsRDT, conventional RDT (cRDT or SD Bioline Malaria Ag Pf/P.v), and QuantStudio™ 3 Real—Time PCR system (qPCR). The hsRDT was compared to cRDT and microscopy. qPCR and microscopy were used as reference methods.
Results
The prevalence of Plasmodium falciparum was 1.51%, 2.2%. 2.2% and 4.52%, by microscopy, hsRDT, cRDT and qPCR, respectively. Using qPCR as reference, the sensitivity of hsRDT was higher (48.89%) than the microscopy (33.3%), and showed 100% specificity and a positive predictive value (PPV). Microscopy showed similar specificity and PPV as hsRDT. Using microscopy as a reference, the diagnostic perforrmances of both hsRDT and cRDT were similar. Both RDTs demonstrated identical diagnostic performances in both comparison methods.
Conclusions
hsRDT has the same diagnostic performance as cRDT but improved diagnostic characteristics than microscopy for detection of P. falciparum in school children with asymptomatic malaria. It can be a useful tool for the national malaria elimination plan of Ethiopia.
Collapse
|
7
|
Rationalization of the Laboratory Diagnosis for Good Management of Malaria: Lessons from Transitional Methods. J Trop Med 2022; 2022:5883173. [PMID: 35502242 PMCID: PMC9056208 DOI: 10.1155/2022/5883173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/27/2021] [Accepted: 04/09/2022] [Indexed: 11/28/2022] Open
Abstract
Introduction Malaria is an endemic disease in sub-Saharan Africa. In clinical practice, the main concern is the overdiagnosis of malaria leading to inappropriate drug prescription without laboratory confirmation. Objective This study aimed to evaluate clinical examination reliability compared with translational laboratory methods of malaria diagnosis. Methods The study was conducted in Goundi Hospital among hospitalized patients over a seven-month period. Patients were interviewed, and malaria tests done included the Giemsa-stained thick and thin blood smears. Diagnostic accuracy was analysed by calculating sensitivity, specificity, and predictive values. Results Among 1,874 participants, 674 (35.96%) patients had positive Giemsa-stained thick blood films. The rate of positivity is higher for patients under 5 years of age. The parasite densities were between 160 and 84.000 parasites/μL. The threshold pyrogen of the parasitic density was around 10.000 parasites/μL for patients between 0 and 11 months of age, between 1 and 4 years of age, and between 5 and 14 years of age. This threshold was lower for patients over 15 years of age. The study reported some issues in the findings: 60.88% (607/997) cases of fever without positivity of the blood thick smear and 40.13% (284/674) cases of positivity of the thick drop without fever. The positive predictive value of malaria was between 80 and 85% for patients under 5 years of age. This value is lower for patients between 5 and 14 years of age and patients over 15 years of age. Conclusion A presumptive diagnosis of malaria should be confirmed by the laboratory in all suspected cases in all possible scenarios. Every parasitemia should be followed by the calculation of parasitic density. However, for the children under 5 years of age in areas of high transmission, the presumptive diagnosis of malaria in certain circumstances could be considered.
Collapse
|
8
|
Fitri LE, Widaningrum T, Endharti AT, Prabowo MH, Winaris N, Nugraha RYB. Malaria diagnostic update: From conventional to advanced method. J Clin Lab Anal 2022; 36:e24314. [PMID: 35247002 PMCID: PMC8993657 DOI: 10.1002/jcla.24314] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 02/11/2022] [Accepted: 02/16/2022] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Update diagnostic methods play essential roles in dealing with the current global malaria situation and decreasing malaria incidence. AIM Global malaria control programs require the availability of adequate laboratory tests in the quick and convenient field. RESULTS There are several methods to find out the existence of parasites within the blood. The oldest one is by microscopy, which is still a gold standard, although rapid diagnostic tests (RDTs) have rapidly become a primary diagnostic test in many endemic areas. Because of microscopy and RDTs limitation, novel serological and molecular methods have been developed. Many kinds of polymerase chain reaction (PCR) provide rapid results and higher specificity and sensitivity. The loop-mediated isothermal amplification (LAMP) and biosensing-based molecular techniques as point of care tests (POCT) will become a cost-effective approach to advance diagnostic testing. CONCLUSION Despite conventional techniques are still being used in the field, the exploration and field implementation of advanced techniques for the diagnosis of malaria are still being developed rapidly.
Collapse
Affiliation(s)
- Loeki Enggar Fitri
- Department of Parasitology, Faculty of Medicine Universitas Brawijaya, Malang, Indonesia.,Malaria Research Group, Faculty of Medicine Universitas Brawijaya, Malang, Indonesia
| | - Tarina Widaningrum
- Malaria Research Group, Faculty of Medicine Universitas Brawijaya, Malang, Indonesia.,Department of Pharmacology, Faculty of Medicine Universitas Brawijaya, Malang, Indonesia
| | - Agustina Tri Endharti
- Department of Parasitology, Faculty of Medicine Universitas Brawijaya, Malang, Indonesia
| | - Muhammad Hatta Prabowo
- Department of Pharmacy, Faculty of Science Universitas Islam Indonesia, Sleman, Indonesia
| | - Nuning Winaris
- Department of Parasitology, Faculty of Medicine Universitas Brawijaya, Malang, Indonesia.,Malaria Research Group, Faculty of Medicine Universitas Brawijaya, Malang, Indonesia
| | - Rivo Yudhinata Brian Nugraha
- Department of Parasitology, Faculty of Medicine Universitas Brawijaya, Malang, Indonesia.,Malaria Research Group, Faculty of Medicine Universitas Brawijaya, Malang, Indonesia
| |
Collapse
|
9
|
Dahal P, Khanal B, Rai K, Kattel V, Yadav S, Bhattarai NR. Challenges in Laboratory Diagnosis of Malaria in a Low-Resource Country at Tertiary Care in Eastern Nepal: A Comparative Study of Conventional vs. Molecular Methodologies. J Trop Med 2021; 2021:3811318. [PMID: 34992661 PMCID: PMC8727160 DOI: 10.1155/2021/3811318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 12/13/2021] [Indexed: 11/17/2022] Open
Abstract
For ongoing malaria elimination programmes, available methods such as microscopy and rapid diagnostic tests (RDTs) cannot detect all malaria cases in acute febrile illness. These methods are entirely dependent on the course of infection, parasite load, and skilled technical resources. Our study objectives were to estimate the performance of light microscopy and a RDT as well as real-time PCR for the detection of the Plasmodium parasite. Altogether, 52 blood samples collected from patients with acute febrile illness were tested by microscopy, RDT, and real-time PCR. The results were compared in terms of sensitivity and specificity. Microscopy detected the malaria parasite in 5.8% of the blood samples whereas 13.5% were detected by the RDT and 27% by real-time PCR. Considering real-time PCR as the gold standard method, microscopy had a sensitivity of 21.4% and a specificity of 100%, and the RDT had a sensitivity of 28.6% and a specificity of 92.1%. Microscopy together with the RDT successfully detected malaria positive cases in blood samples of Ct value below 20, but both were unable to detect malaria cases between 26-40 Ct value ranges amplified by real-time PCR. Despite various diagnostic tools being available, microscopy still remains the method of choice for diagnosis, while the RDT is user-friendly when applied at the point of care. However, our preliminary results emphasize the need to implement the test with higher sensitivity and specificity in the context of a malaria elimination programme. Such programmes can be a crucial opportunity to understand the species prevalent in a low-endemic region. However, these results should be further verified with a large cohort study to document the submicroscopic infection.
Collapse
Affiliation(s)
- Pragyan Dahal
- Department of Microbiology, B. P. Koirala Institute of Health Sciences, Dharan, Nepal
| | - Basudha Khanal
- Department of Microbiology, B. P. Koirala Institute of Health Sciences, Dharan, Nepal
| | - Keshav Rai
- Department of Microbiology, B. P. Koirala Institute of Health Sciences, Dharan, Nepal
| | - Vivek Kattel
- Department of Internal Medicine, B. P. Koirala Institute of Health Sciences, Dharan, Nepal
| | - Satish Yadav
- Department of Pediatrics, B. P. Koirala Institute of Health Sciences, Dharan, Nepal
| | - Narayan Raj Bhattarai
- Department of Microbiology, B. P. Koirala Institute of Health Sciences, Dharan, Nepal
| |
Collapse
|
10
|
Brilhante-da-Silva N, do Nascimento Martinez L, de Oliveira Sousa RM, dos Santos Pereira S, Teles CBG. Innovations in Plasmodium spp . diagnosis on diverse detection platforms. 3 Biotech 2021; 11:505. [PMID: 34881167 DOI: 10.1007/s13205-021-03054-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 11/03/2021] [Indexed: 10/19/2022] Open
Abstract
In 2019, 229 million cases of malaria were recorded worldwide. For epidemiologic surveillance and proper treatment of persons infected with Plasmodium spp., rapid detection of infections by Plasmodium spp. is critical. Thus, Plasmodium spp. diagnosis is one of the indispensable measures for malaria control. Although microscopy is the gold standard for diagnosis, it has restrictions related mainly to the lack of qualified human resources, which is a problem in many regions. Thus, this review presents major innovations in diagnostic methods as alternatives to or complementary to microscopy. Detection platforms in lateral flow systems, electrochemical immunosensors, molecular biology and, more recently, those integrated with smartphones, are highlighted, among others. The advanced improvement of these tests aims to provide techniques that are sensitive and specific, but also quick, easy to handle and free from the laboratory environment. In this way, the tracking of malaria cases can become increasingly effective and contribute to controlling the disease.
Collapse
|
11
|
Wu J, Wang P, Han Z, Li T, Yi C, Qiu C, Yang Q, Sun G, Dai L, Shi J, Wang K, Ye H. A novel immunodiagnosis panel for hepatocellular carcinoma based on bioinformatics and the autoantibody-antigen system. Cancer Sci 2021; 113:411-422. [PMID: 34821436 PMCID: PMC8819288 DOI: 10.1111/cas.15217] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/26/2021] [Accepted: 11/08/2021] [Indexed: 12/11/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is a malignancy with a dismal survival rate. The novel autoantibodies panel may provide new insights for the diagnosis of HCC. Biomarkers screened by two methods (bioinformatics and the antigen‐antibody system) were taken as candidate tumor‐associated antigens (TAAs). Enzyme‐linked immunosorbent assay was used to detect the corresponding autoantibodies in 888 samples of verification and validation cohorts. The verification cohort was used to verify the autoantibodies. Samples in the validation cohort were randomly divided into a train set and a test set with the ratio of 6:4. A diagnostic model was established by support vector machines within the train set. The test set further verified the model. Eleven TAAs were selected (AAGAB, C17orf75, CDC37L1, DUSP6, EID3, PDIA2, RGS20, PCNA, TAF7L, TBC1D13, and ZIC2). The titer of six autoantibodies (PCNA, AAGAB, CDC37L1, TAF7L, DUSP6, and ZIC2) had a significant difference in any of the pairwise comparisons among the HCC, liver cirrhosis, and normal control groups. The titer of these autoantibodies had an increasing tendency. Finally, an optimum diagnostic model was constructed with the six autoantibodies. The AUCs were 0.826 in the train set and 0.773 in the test set. The area under the curve (AUC) of this panel for diagnosing early HCC was 0.889. The diagnostic ability of the panel reduced with the progress of HCC. The positive rate of the panel in diagnosing alpha‐fetoprotein (AFP)‐negative patients was 75.6%. For early HCC, the sensitivity of the combination of AFP with the panel was 90.9% and superior to 53.2% of AFP alone. The novel immunodiagnosis panel combining AFP may be a new approach for the diagnosis of HCC, especially for early‐HCC cases.
Collapse
Affiliation(s)
- Jinyu Wu
- College of Public Health, Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China
| | - Peng Wang
- College of Public Health, Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China
| | - Zhuo Han
- College of Public Health, Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China
| | - Tiandong Li
- College of Public Health, Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China
| | - Chuncheng Yi
- College of Public Health, Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China
| | - Cuipeng Qiu
- Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China.,Henan Institute of Medical and Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
| | - Qian Yang
- College of Public Health, Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China
| | - Guiying Sun
- College of Public Health, Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China
| | - Liping Dai
- Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China.,Henan Institute of Medical and Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
| | - Jianxiang Shi
- Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China.,Henan Institute of Medical and Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
| | - Keyan Wang
- Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China.,Henan Institute of Medical and Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
| | - Hua Ye
- College of Public Health, Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Tumor Epidemiology and State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, China
| |
Collapse
|
12
|
Assessing the Performance of CareStart™ Malaria Rapid Diagnostic Tests in Northwest Ethiopia: A Cross-Sectional Study. J Parasitol Res 2021; 2021:7919984. [PMID: 34725569 PMCID: PMC8556986 DOI: 10.1155/2021/7919984] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 10/05/2021] [Indexed: 11/18/2022] Open
Abstract
Background While rapid diagnostic tests are an alternative diagnostic tests for microscopy in the diagnosis of malaria in rural settings, their performance has been inconsistent. Performance of rapid diagnostic tests might be affected by manufacturing process, transportation and storage, parasitemia level, and skill of personnel who perform the tests. Therefore, periodic evaluation of the local field performance of rapid diagnostic tests is mandatory in order to make early corrections in case of decreased performance. Methods A facility-based cross-sectional study was conducted from January to May 2020 among 257 malaria-suspected patients attending selected health centers in Bahir Dar Zuria district. Capillary blood was collected from each participant and tested for Plasmodium infection by CareStart™ rapid diagnostic test kit and thin and thick blood film microscopy. Data were analyzed using statistical software for social sciences version 20 and MedCalc software version 19.3. Sensitivity, specificity, positive and negative predictive values, and kappa value were calculated to evaluate the performance of rapid diagnostic tests against microscopy. Results Among 257 study participants, 47 (18.3%) were tested positive for Plasmodium infection by at least one of the diagnostic methods. Rapid diagnostic tests revealed 3 false positive and 3 false negative results. The sensitivity and specificity of CareStart Malaria Pf/Pv Combo test were 93.2% and 98.6%, respectively (kappa = 0.918). Conclusion CareStart™ rapid diagnostic test has comparable performance with microscopy for malaria diagnosis. We recommend continued use of CareStart Malaria Pf/Pv Combo test at health posts in Ethiopia where microscopy is not available.
Collapse
|
13
|
Diagnostic Accuracy of CareStart™ Malaria HRP2 and SD Bioline Pf/PAN for Malaria in Febrile Outpatients in Varying Malaria Transmission Settings in Cameroon. Diagnostics (Basel) 2021; 11:diagnostics11091556. [PMID: 34573898 PMCID: PMC8469216 DOI: 10.3390/diagnostics11091556] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/29/2021] [Accepted: 08/09/2021] [Indexed: 11/21/2022] Open
Abstract
Background: There was an increase in the number of malaria cases in Cameroon in 2018 that could reflect changes in provider practice, despite effective interventions. In this study, we assessed the diagnostic performance of two malaria rapid diagnostic tests (mRDTs) for diagnostic confirmation of suspected cases of malaria in public and private health facilities in two malaria transmission settings in Cameroon. Methods: We evaluated the diagnostic performance of CareStart pf and SD Bioline Pf/PAN mRDT and compared these parameters by RDT type and transmission setting. Nested PCR and blood film microscopy were used as references. The chi square test was used for independent sample comparisons, while the McNemar’s test was used to test for the dependence of categorical data in paired sample testing. A p < 0.05 was considered significant in all comparisons. The R (v.4.0.2) software was used for analyses. Results: A total of 1126 participants consented for the study in the four sites. The diagnostic accuracy of the CareStart Pf mRDT was 0.93.6% (0.911–0.961) in Yaoundé, 0.930% (0.90–0.960) in Ngounso, 0.84% (0.794–0.891) in St Vincent Catholic Hospital Dschang and 0.407 (0.345–0.468) in Dschang district hospital. For SD Bioline Pf/PAN the accuracy was 0.759 (0.738–0.846) for St Vincent Catholic Hospital Dschang and 0.426 (0.372–0.496) for the Dschang district hospital. The accuracy was slightly lower in each case but not statistically different when PCR was considered as the reference. The likelihood ratios of the positive and negative tests were high in the high transmission settings of Yaoundé (10.99 (6.24–19.35)) and Ngounso (14.40 (7.89–26.28)) compared to the low transmission settings of Dschang (0.71 (0.37–1.37)) and St Vincent Catholic hospital (7.37 (4.32−12.59)). There was a high degree of agreement between the tests in Yaoundé (Cohen’s Kappa: 0.85 ± 0.05 (0.7–0.95)) and Ngounso (Cohen’s Kappa: 0.86 ± 0.05 (0.74, 0.97)) and moderate agreement in St Vincent hospital Dschang (k: 0.58 ± 0.06 (0.44–0.71)) and poor agreement in the District Hospital Dschang (Cohen’s Kappa: −0.11 ± 0.05 (−0.21–0.01)). The diagnostic indicators of the SD Bioline Pf/PAN were slightly better than for CareStart Pf mRDT in St Vincent Catholic hospital Dschang, irrespective of the reference test. Conclusions: Publicly procured malaria rapid diagnostic tests in Cameroon have maintained high accuracy (91–94%) in the clinical diagnosis of malaria in high malaria transmission regions of Cameroon, although they failed to reach WHO standards. We observed an exception in the low transmission region of Dschang, West region, where the accuracy tended to be lower and variable between facilities located in this town. These results underscore the importance of the routine monitoring of the quality and performance of malaria RDTs in diverse settings in malaria endemic areas.
Collapse
|
14
|
Minakawa N, Kongere JO, Sonye GO, Lutiali PA, Awuor B, Kawada H, Isozumi R, Futami K. Long-Lasting Insecticidal Nets Incorporating Piperonyl Butoxide Reduce the Risk of Malaria in Children in Western Kenya: A Cluster Randomized Controlled Trial. Am J Trop Med Hyg 2021; 105:461-471. [PMID: 34125699 PMCID: PMC8437186 DOI: 10.4269/ajtmh.20-1069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 03/22/2021] [Indexed: 11/10/2022] Open
Abstract
Malaria vectors have acquired an enzyme that metabolizes pyrethroids. To tackle this problem, we evaluated long-lasting insecticidal nets incorporating piperonyl butoxide (PBO-LLINs) with a community-based cluster randomized control trial in western Kenya. The primary endpoints were anopheline density and Plasmodium falciparum polymerase chain reaction (PCR)-positive prevalence (PCRpfPR) of children aged 7 months to 10 years. Four clusters were randomly selected for each of the treatment and control arms (eight clusters in total) from 12 clusters, and PBO-LLINs and standard LLINs were distributed in February 2011 to 982 and 1,028 houses for treatment and control arms, respectively. Entomological surveys targeted 20 houses in each cluster, and epidemiological surveys targeted 150 children. Cluster-level permutation tests evaluated the effectiveness using the fitted values from individual level regression models adjusted for baseline. Bootstrapping estimated 95% confidence intervals (CIs). The medians of anophelines per house were 1.4 (interquartile range [IQR]: 2.3) and 3.4 (IQR: 3.7) in the intervention and control arms after 3 months, and 0.4 (IQR: 0.2) and 1.6 (IQR: 0.5) after 10 months, respectively. The differences were -2.5 (95% CI: -6.4 to -0.6) and -1.3 (95% CI: -2.0 to -0.7), respectively. The datasets of 861 and 775 children were analyzed in two epidemiological surveys. The median PCRpfPRs were 25% (IQR: 11%) in the intervention arm and 52% (IQR: 11%) in the control arm after 5 months and 33% (IQR: 11%) and 45% (IQR: 5%) after 12 months. The PCRpfPR ratios were 0.67 (95% CI: 0.38, 0.91) and 0.74 (95% CI: 0.53, 0.90), respectively. We confirmed the superiority of PBO-LLINs.
Collapse
Affiliation(s)
- Noboru Minakawa
- Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan
| | - James O. Kongere
- Kenya Medical Research Institute, Nairobi, Kenya
- Center for Research in Tropical Medicine and Community Development (CRTMCD), Nairobi, Kenya
| | | | - Peter A. Lutiali
- Kenya Medical Research Institute, Nairobi, Kenya
- Center for Research in Tropical Medicine and Community Development (CRTMCD), Nairobi, Kenya
| | | | - Hitoshi Kawada
- Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan
| | - Rie Isozumi
- Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan
| | - Kyoko Futami
- Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan
| |
Collapse
|
15
|
Morang'a CM, Amenga-Etego L, Bah SY, Appiah V, Amuzu DSY, Amoako N, Abugri J, Oduro AR, Cunnington AJ, Awandare GA, Otto TD. Machine learning approaches classify clinical malaria outcomes based on haematological parameters. BMC Med 2020; 18:375. [PMID: 33250058 PMCID: PMC7702702 DOI: 10.1186/s12916-020-01823-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 10/22/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Malaria is still a major global health burden, with more than 3.2 billion people in 91 countries remaining at risk of the disease. Accurately distinguishing malaria from other diseases, especially uncomplicated malaria (UM) from non-malarial infections (nMI), remains a challenge. Furthermore, the success of rapid diagnostic tests (RDTs) is threatened by Pfhrp2/3 deletions and decreased sensitivity at low parasitaemia. Analysis of haematological indices can be used to support the identification of possible malaria cases for further diagnosis, especially in travellers returning from endemic areas. As a new application for precision medicine, we aimed to evaluate machine learning (ML) approaches that can accurately classify nMI, UM, and severe malaria (SM) using haematological parameters. METHODS We obtained haematological data from 2,207 participants collected in Ghana: nMI (n = 978), SM (n = 526), and UM (n = 703). Six different ML approaches were tested, to select the best approach. An artificial neural network (ANN) with three hidden layers was used for multi-classification of UM, SM, and uMI. Binary classifiers were developed to further identify the parameters that can distinguish UM or SM from nMI. Local interpretable model-agnostic explanations (LIME) were used to explain the binary classifiers. RESULTS The multi-classification model had greater than 85% training and testing accuracy to distinguish clinical malaria from nMI. To distinguish UM from nMI, our approach identified platelet counts, red blood cell (RBC) counts, lymphocyte counts, and percentages as the top classifiers of UM with 0.801 test accuracy (AUC = 0.866 and F1 score = 0.747). To distinguish SM from nMI, the classifier had a test accuracy of 0.96 (AUC = 0.983 and F1 score = 0.944) with mean platelet volume and mean cell volume being the unique classifiers of SM. Random forest was used to confirm the classifications, and it showed that platelet and RBC counts were the major classifiers of UM, regardless of possible confounders such as patient age and sampling location. CONCLUSION The study provides proof of concept methods that classify UM and SM from nMI, showing that the ML approach is a feasible tool for clinical decision support. In the future, ML approaches could be incorporated into clinical decision-support algorithms for the diagnosis of acute febrile illness and monitoring response to acute SM treatment particularly in endemic settings.
Collapse
Affiliation(s)
- Collins M Morang'a
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Lucas Amenga-Etego
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana.
| | - Saikou Y Bah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana.,Florey Institute, Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - Vincent Appiah
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Dominic S Y Amuzu
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Nicholas Amoako
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - James Abugri
- Department of Applied Chemistry and Biochemistry, C. K Tedam University of Technology and Applied Sciences, Navrongo, Ghana
| | - Abraham R Oduro
- Ministry of Health, Navrongo Health Research Centre (NHRC), Navrongo, Ghana
| | - Aubrey J Cunnington
- Section of Pediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, UK
| | - Gordon A Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Thomas D Otto
- Institute of Infection, Immunity & Inflammation, MVLS, University of Glasgow, Glasgow, UK.
| |
Collapse
|
16
|
Gachugia J, Chebore W, Otieno K, Ngugi CW, Godana A, Kariuki S. Evaluation of the colorimetric malachite green loop-mediated isothermal amplification (MG-LAMP) assay for the detection of malaria species at two different health facilities in a malaria endemic area of western Kenya. Malar J 2020; 19:329. [PMID: 32907582 PMCID: PMC7487890 DOI: 10.1186/s12936-020-03397-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 08/30/2020] [Indexed: 01/03/2023] Open
Abstract
Background Prompt diagnosis and effective malaria treatment is a key strategy in malaria control. However, the recommended diagnostic methods, microscopy and rapid diagnostic tests (RDTs), are not supported by robust quality assurance systems in endemic areas. This study compared the performance of routine RDTs and smear microscopy with a simple molecular-based colorimetric loop-mediated isothermal amplification (LAMP) at two different levels of the health care system in a malaria-endemic area of western Kenya. Methods Patients presenting with clinical symptoms of malaria at Rota Dispensary (level 2) and Siaya County Referral Hospital (level 4) were enrolled into the study after obtaining written informed consent. Capillary blood was collected to test for malaria by RDT and microscopy at the dispensary and county hospital, and for preparation of blood smears and dried blood spots (DBS) for expert microscopy and real-time polymerase chain reaction (RT-PCR). Results of the routine diagnostic tests were compared with those of malachite green loop-mediated isothermal amplification (MG-LAMP) performed at the two facilities. Results A total of 264 participants were enrolled into the study. At the dispensary level, the positivity rate by RDT, expert microscopy, MG-LAMP and RT-PCR was 37%, 30%, 44% and 42%, respectively, and 42%, 43%, 57% and 43% at the county hospital. Using RT-PCR as the reference test, the sensitivity of RDT and MG-LAMP was 78.1% (CI 67.5–86.4) and 82.9% (CI 73.0–90.3) at Rota dispensary. At Siaya hospital the sensitivity of routine microscopy and MG-LAMP was 83.3% (CI 65.3–94.4) and 93.3% (CI 77.9–99.2), respectively. Compared to MG-LAMP, there were 14 false positives and 29 false negatives by RDT at Rota dispensary and 3 false positives and 13 false negatives by routine microscopy at Siaya Hospital. Conclusion MG-LAMP is more sensitive than RDTs and microscopy in the detection of malaria parasites at public health facilities and might be a useful quality control tool in resource-limited settings.
Collapse
Affiliation(s)
- James Gachugia
- Department of Medical Microbiology, College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, P. O. Box 62000-00200, Nairobi, Kenya
| | - Winnie Chebore
- Kenya Medical Research Institute, Centre for Global Health Research, P. O. Box 1578-40100, Kisumu, Kenya
| | - Kephas Otieno
- Kenya Medical Research Institute, Centre for Global Health Research, P. O. Box 1578-40100, Kisumu, Kenya
| | - Caroline Wangari Ngugi
- Department of Medical Microbiology, College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, P. O. Box 62000-00200, Nairobi, Kenya
| | - Adano Godana
- National Malaria Control Programme, Ministry of Health, Kenyatta National Hospital, P. O. Box, Nairobi, 19982-00202, Kenya
| | - Simon Kariuki
- Kenya Medical Research Institute, Centre for Global Health Research, P. O. Box 1578-40100, Kisumu, Kenya.
| |
Collapse
|
17
|
Xie Y, Wu K, Cheng W, Jiang T, Yao Y, Xu M, Yang Y, Tan H, Li J. Molecular epidemiological surveillance of Africa and Asia imported malaria in Wuhan, Central China: comparison of diagnostic tools during 2011-2018. Malar J 2020; 19:321. [PMID: 32883296 PMCID: PMC7470674 DOI: 10.1186/s12936-020-03387-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 08/25/2020] [Indexed: 01/17/2023] Open
Abstract
Background Malaria remains a serious public health problem globally. As the elimination of indigenous malaria continues in China, imported malaria has gradually become a major health hazard. Well-timed and accurate diagnoses could support the timely implementation of therapeutic schedules, reveal the prevalence of imported malaria and avoid transmission of the disease. Methods Blood samples were collected in Wuhan, China, from August 2011 to December 2018. All patients accepted microscopy and rapid diagnosis test (RDT) examinations. Subsequently, each of the positive or suspected positive cases was tested for four human-infectious Plasmodium species by using 18S rRNA-based nested PCR and Taqman probe-based real-time PCR. The results of the microscopy and the two molecular diagnostic methods were analysed. Importation origins were traced by country, and the prevalence of Plasmodium species was analysed by year. Results A total of 296 blood samples, including 288 that were microscopy and RDT positive, 7 RDT and Plasmodium falciparum positive, and 1 suspected case, were collected and reanalysed. After application of the two molecular methods and sequencing, 291 cases including 245 P. falciparum, 15 Plasmodium vivax, 20 Plasmodium ovale, 6 Plasmodium malariae and 5 mixed infections (3 P. falciparum + P. ovale, 2 P. vivax + P. ovale) were confirmed. These patients had returned from Africa (95.53%) and Asia (4.47%). Although the prevalence displayed a small-scale fluctuation, the overall trend of the imported cases increased yearly. Conclusions These results emphasize the necessity of combined utilization of the four tools for malaria diagnosis in clinic and in field surveys of potential risk regions worldwide including Wuhan.
Collapse
Affiliation(s)
- Yiting Xie
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Kai Wu
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, People's Republic of China
| | - Weijia Cheng
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Tingting Jiang
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Yi Yao
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Mingxing Xu
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, People's Republic of China
| | - Yan Yang
- Department of Schistosomiasis and Endemic Diseases, Wuhan City Center for Disease Prevention and Control, Wuhan, 430015, People's Republic of China
| | - Huabing Tan
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China
| | - Jian Li
- Department of Human Parasitology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, 442000, People's Republic of China. .,Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, People's Republic of China.
| |
Collapse
|
18
|
Alemayehu GS, Lopez K, Dieng CC, Lo E, Janies D, Golassa L. Evaluation of PfHRP2 and PfLDH Malaria Rapid Diagnostic Test Performance in Assosa Zone, Ethiopia. Am J Trop Med Hyg 2020; 103:1902-1909. [PMID: 32840197 DOI: 10.4269/ajtmh.20-0485] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In malaria-endemic countries, rapid diagnostic tests (RDTs) targeting Plasmodium falciparum histidine-rich protein 2 (PfHRP2) and lactate dehydrogenase (PfLDH) have been widely used. However, little is known regarding the diagnostic performances of these RDTs in the Assosa zone of northwest Ethiopia. The objective of this study was to determine the diagnostic performances of PfHRP2 and PfLDH RDTs using microscopy and quantitative PCR (qPCR) as a reference test. A health facility-based cross-sectional study design was conducted from malaria-suspected study participants at selected health centers from November to December 2018. Finger-prick blood samples were collected for microscopy, RDTs, and qPCR method. The prevalence of P. falciparum was 26.4%, 30.3%, and 24.1% as determined by microscopy, PfHRP2 RDT, and PfLDH RDT, respectively. Compared with microscopy, the sensitivity and specificity of the PfHRP2 RDT were 96% and 93%, respectively, and those of the PfLDH RDT were 89% and 99%, respectively. Compared with qPCR, the specificity of the PfHRP2 RDT (93%) and PfLDH RDT (98%) was high, but the sensitivity of the PfHRP2 RDT (77%) and PfLDH RDT (70%) was relatively low. These malaria RDTs and reference microscopy methods showed reasonable agreement with a kappa value above 0.85 and provided accurate diagnosis of P. falciparum malaria. Thus, the current malaria RDT in the Ministry of Health program can be used in the Assosa zone of Ethiopia. However, continuous monitoring of the performance of PfHRP2 RDT is important to support control and elimination of malaria in Ethiopia.
Collapse
Affiliation(s)
| | - Karen Lopez
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, North Carolina
| | - Cheikh Cambel Dieng
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, North Carolina
| | - Eugenia Lo
- Department of Biological Sciences, University of North Carolina at Charlotte, Charlotte, North Carolina
| | - Daniel Janies
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, North Carolina
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| |
Collapse
|
19
|
Mbohou Nchetnkou C, Nyabeyeu Nyabeyeu H, Kojom Foko LP, Lehman LG. Comparison of the fluorescence microscopy Cyscope® with light microscopy for malaria diagnosis in a small and active surveillance in Cameroon. Trop Med Health 2020; 48:61. [PMID: 32742185 PMCID: PMC7385968 DOI: 10.1186/s41182-020-00234-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 05/28/2020] [Indexed: 12/27/2022] Open
Abstract
Background Malaria has a negative impact on the activities of companies in endemic countries especially in Cameroon. In this regard, an increasingly growing number of companies have started to include management of malarious patients in their health policies. In the present study, we will evaluate the diagnostic performances of a fluorescence microscopy (FM), Cyscope® microscope, in the detection of malaria parasites. Methods A cross-sectional study was conducted among employees of two companies of the town of Douala on 21 and 22 March 2017. Sociodemographic information of employees was collected using a questionnaire form. Blood samples of ~ 10 μL were collected by venipuncture for the diagnosis of malaria using FM and light microscopy (LM). Performances of FM with respect to sensitivity (Se), specificity (Sp), positive and negative predictive values (PPV and NPV), positive and negative likelihood rates (PLR and NLR), accuracy, reliability, and Kappa index were calculated using LM as gold standard. Results In total, 442 employees, aged 37.8 ± 9.7 years old on average, were included in the study. Prevalence of malaria using FM and LM was 39.2% and 17%, respectively (p < 0.01). Plasmodium falciparum and P. vivax were the two species involved in malaria infection cases. In terms of developmental stages, 68%, 45.3%, and 1.3% of employees carried gametocytes, trophozoites, and schizonts, respectively. Findings on diagnostic performances of FM were as follows: Se = 84%, Sp = 69.95%, PPV = 63.58%, NPV = 95.5%, accuracy = 89.36%, and reliability = 53.95%. Sensitivity of Cyscope® microscope increased as a function of parasitemia with values ranging from 76.92% at parasitemia between 1 and 500 parasites/μL to 91.11% at parasitemia between 501 and 5000 parasites/μL. The geometric mean parasite density was1850 parasites per μL of blood (range 1600-40,000), and most of employees (60.8%) had moderate parasitemia. The performances of FM were similar between febrile and afebrile patients. Conclusions This study showed good performances of Cyscope® microscope and outlines that this diagnostic tool could be used in management of malaria at workplace.
Collapse
Affiliation(s)
- Christian Mbohou Nchetnkou
- Department of Animal Organisms, Faculty of Science, The University of Douala, P.O. Box 24157, Douala, Cameroon
| | - Hervé Nyabeyeu Nyabeyeu
- Department of Animal Organisms, Faculty of Science, The University of Douala, P.O. Box 24157, Douala, Cameroon
| | - Loick P Kojom Foko
- Department of Animal Organisms, Faculty of Science, The University of Douala, P.O. Box 24157, Douala, Cameroon
| | - Leopold G Lehman
- Department of Animal Organisms, Faculty of Science, The University of Douala, P.O. Box 24157, Douala, Cameroon.,Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, The University of Douala, P.O. Box 24157, Douala, Cameroon
| |
Collapse
|
20
|
Lumbala C, Matovu E, Sendagire H, Kazibwe AJN, Likwela JL, Muhindo Mavoko H, Kayembe S, Lutumba P, Biéler S, Van Geertruyden JP, Ndung’u JM. Performance evaluation of a prototype rapid diagnostic test for combined detection of gambiense human African trypanosomiasis and malaria. PLoS Negl Trop Dis 2020; 14:e0008168. [PMID: 32251426 PMCID: PMC7162526 DOI: 10.1371/journal.pntd.0008168] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 04/16/2020] [Accepted: 02/24/2020] [Indexed: 11/18/2022] Open
Abstract
Background Malaria is endemic in all regions where gambiense or rhodesiense human African trypanosomiasis (HAT) is reported, and both diseases have similarities in their symptomatology. A combined test could be useful for both diseases and would facilitate integration of the screening for gambiense HAT (gHAT) and malaria diagnosis. This study aimed to evaluate a combined prototype rapid diagnostic test (RDT) for gHAT and malaria. Methods Blood samples were collected in the Democratic Republic of the Congo and in Uganda to evaluate the performance of a prototype HAT/Malaria Combined RDT in comparison to an individual malaria RDT based on Plasmodium falciparum (P.f.) Histidine Rich Protein II (HRP-II or HRP2) antigen (SD BIOLINE Malaria Ag P.f. RDT) for malaria detection and an individual gHAT RDT based on recombinant antigens, the SD BIOLINE HAT 2.0 RDT for HAT screening. Due to the current low prevalence of gHAT in endemic regions, the set of blood samples that were collected was used to evaluate the specificity of the RDTs for gHAT, and additional archived plasma samples were used to complete the evaluation of the HAT/Malaria Combined RDT in comparison to the HAT 2.0 RDT. Results Frozen whole blood samples from a total of 486 malaria cases and 239 non-malaria controls, as well as archived plasma samples from 246 gHAT positive and 246 gHAT negative individuals were tested. For malaria, the sensitivity and specificity of the malaria band in the HAT/Malaria Combined RDT were 96.9% (95% CI: 95.0–98.3) and 97.1% (95% CI: 94.1–98.8) respectively. The sensitivity and specificity of the SD BIOLINE malaria Ag P.f. RDT were 97.3% (95% CI: 95.5–98.6) and 97.1% (95% CI: 94.1–98.8) respectively. For gHAT, using archived plasma samples, the sensitivity and specificity were respectively 89% (95% CI: 84.4–92.6) and 93.5% (95% CI: 89.7–96.2) with the HAT/Malaria Combined RDT, and 88.2% (95% CI: 83.5–92) and 94.7% (95% CI: 91.1–97.2) with the HAT 2.0 RDT. Using the whole blood samples that were collected during the study, the specificity of the HAT/Malaria Combined RDT for gHAT was 95.8% (95% CI: 94.3–97.0). Conclusion The HAT/Malaria Combined prototype RDT was as accurate as the individual malaria or gHAT RDTs. The HAT/Malaria Combined prototype RDT is therefore suitable for both malaria diagnosis and gHAT screening. However, there is a need to assess its accuracy using fresh samples in prospective clinical trials. The annual number of reported cases of human African trypanosomiasis (HAT), also known as sleeping sickness (SS), is currently below 1,000 cases worldwide. The Democratic Republic of the Congo (DRC), the most affected country, and Uganda, which shares a border with DRC, are both endemic for gambiense HAT (gHAT). The main strategy to control gHAT is screening of at-risk individuals, followed by diagnosis and treatment of confirmed cases. However, this strategy and even the passive screening as currently implemented become less efficient with declining incidence, justifying innovative strategies to efficiently detect the remaining cases. All areas where gHAT occurs are also endemic for malaria, presenting an opportunity to integrate gHAT screening activities within malaria control activities. This integration is warranted by the fact that in early disease stage, gHAT patients present with signs and symptoms strikingly similar to those of malaria. In order to use malaria diagnosis as an entry point to screen for gHAT, Standard Diagnostics (SD), Republic of Korea (now Abbott Diagnostics, Korea Inc–ADK) made a Combined prototype RDT for both malaria and gHAT, expected to be as accurate as the individual gHAT and malaria RDTs. In this study, we evaluated the accuracy of the Combined prototype RDT using whole blood samples collected in Uganda and DRC, and archived plasma samples collected in DRC, Angola and Central African Republic. We found that the Combined prototype performs just as well as individual RDTs.
Collapse
Affiliation(s)
- Crispin Lumbala
- Disease Control Directorate, Ministry of Public Health, Democratic Republic of the Congo
- Global Health Institute, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- * E-mail:
| | - Enock Matovu
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Hakim Sendagire
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Anne J. N. Kazibwe
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Joris L. Likwela
- Public Health Department, Faculty of Medicine and Pharmacy, University of Kisangani, Kisangani, Democratic Republic of the Congo
| | | | - Simon Kayembe
- Foundation for Innovative New Diagnostics (FIND), Geneva, Switzerland
| | - Pascal Lutumba
- Kinshasa University, Kinshasa, Democratic Republic of the Congo
| | - Sylvain Biéler
- Foundation for Innovative New Diagnostics (FIND), Geneva, Switzerland
| | | | - Joseph M. Ndung’u
- Foundation for Innovative New Diagnostics (FIND), Geneva, Switzerland
| |
Collapse
|
21
|
Prevalence of Asymptomatic Malaria among Children in the Tamale Metropolis: How Does the PfHRP2 CareStart™ RDT Perform against Microscopy? J Trop Med 2019; 2019:6457628. [PMID: 31933652 PMCID: PMC6942882 DOI: 10.1155/2019/6457628] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 10/24/2019] [Accepted: 11/26/2019] [Indexed: 11/30/2022] Open
Abstract
Background Asymptomatic carriage of the malaria parasites, likewise its misdiagnosis, especially false negatives, due to the use of substandard rapid diagnosis tests (RDTs) has been shown to hinder the progress of the fight against malaria. Method The study assessed the prevalence of asymptomatic malaria as well as the performance of Plasmodium falciparum-specific protein and histidine-rich protein 2 (PfHRP2) CareStart™ RDT against standard microscopy in the detection of malaria infection among 345 children (1–15 yrs) from two (2) basic schools in Tamale Metropolis. Results From the microscopy (considered as gold standard), prevalence of malaria among the asymptomatic children was found to be 2.6%, with sensitivity and specificity of CareStart™ RDT in detecting P. falciparum infections found to be 55.6% and 93.8%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) of CareStart™ RDT were found to be 19.23% and 98.45%, respectively. There was an evidence showing a significant relation between CareStart™ RDT and microscopy in determining malaria infection (χ2 = 30.579, p < 0.001). Conclusion Prevalence of asymptomatic malaria among children was found to be 2.6%. The study reported low sensitivity and PPV for PfHRP2 CareStart™ RDT in an asymptomatic population at instances of low parasitaemia.
Collapse
|
22
|
Mweu MM, Wambua J, Njuga F, Bejon P, Mwanga D. Bayesian evaluation of the performance of three diagnostic tests for Plasmodium falciparum infection in a low-transmission setting in Kilifi County, Kenya. Wellcome Open Res 2019; 4:67. [PMID: 31595228 PMCID: PMC6777009 DOI: 10.12688/wellcomeopenres.15204.3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2019] [Indexed: 12/15/2022] Open
Abstract
Background: Central to the successful elimination of Plasmodium falciparum malaria, are tests with superior capability of diagnosing low-density parasitaemias. Empirical evidence on the performance of the commonly available diagnostics (light microscopy (LM), rapid diagnostic tests (RDT) and polymerase chain reaction (PCR)) is needed to better inform case management and surveillance activities within primary health care settings where elimination of falciparum malaria is targeted. The objective of this study was to estimate the sensitivity (Se) and specificity (Sp) and predictive values of LM, RDT and PCR tests for P. falciparum infection in children, while evaluating the effect of specific covariates on the accuracy of the tests. Methods: The study enrolled 1,563 children presenting with fever (axillary temperature ≥ 37.5 0C) to the Ngerenya dispensary, Kilifi County between March and December 2014. A Bayesian latent class model (BLCM) was fitted to the participants' diagnostic data obtained from blood samples that were screened for the presence of P. falciparum using the three tests. Results: The PCR assay registered a higher Se (97.6% [92.0; 99.7]) than LM (84.0% [74.8; 91.0]) but similar to RDT (92.2% [84.4; 97.0]). However, the assay showed a similar Sp (98.9% [98.2; 99.4]) to both RDT (99.4% [98.9; 99.7]) and LM (99.5% [99.0; 99.8]). Regarding predictive values, the tests yielded statistically similar estimates of positive and negative predictive values (PPV and NPV). A serial interpretation of the results of RDT and LM raised the PPVs and NPVs to >98%. Conclusions: LM and RDT afford high Se and Sp in symptomatic care-seeking children in this low P. falciparum prevalence setting. A serial combination of the tests assures high PPV and NPV estimates. These elements, coupled with the wide deployment and affordability of the tests, lend the tests useful for guiding clinical care and surveillance activities for P. falciparum within elimination settings.
Collapse
Affiliation(s)
- Marshal M. Mweu
- School of Public Health, University of Nairobi, Nairobi, Kenya
| | | | - Fixtan Njuga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Daniel Mwanga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| |
Collapse
|
23
|
Mweu MM, Wambua J, Njuga F, Bejon P, Mwanga D. Bayesian evaluation of the performance of three diagnostic tests for Plasmodium falciparum infection in a low-transmission setting in Kilifi County, Kenya. Wellcome Open Res 2019; 4:67. [PMID: 31595228 PMCID: PMC6777009 DOI: 10.12688/wellcomeopenres.15204.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2019] [Indexed: 10/15/2023] Open
Abstract
Background: Central to the successful elimination of Plasmodium falciparum malaria, are tests with superior capability of diagnosing low-density parasitaemias. Empirical evidence on the performance of the commonly available diagnostics (light microscopy (LM), rapid diagnostic tests (RDT) and polymerase chain reaction (PCR)) is needed to better inform case management and surveillance activities within primary health care settings where elimination of falciparum malaria is targeted. The objective of this study was to estimate the sensitivity (Se) and specificity (Sp) and predictive values of LM, RDT and PCR tests for P. falciparum infection in children, while evaluating the effect of specific covariates on the accuracy of the tests. Methods: The study enrolled 1,563 children presenting with fever (axillary temperature ≥ 37.50C) to the Ngerenya dispensary, Kilifi County between March and December 2014. A Bayesian latent class model (BLCM) was fitted to the participants' diagnostic data obtained from blood samples that were screened for the presence of P. falciparum using the three tests. Results: The PCR assay registered a higher Se (97.6% [92.0; 99.7]) than LM (84.0% [74.8; 91.0]) but similar to RDT (92.2% [84.4; 97.0]). However, the assay showed a similar Sp (98.9% [98.2; 99.4]) to both RDT (99.4% [98.9; 99.7]) and LM (99.5% [99.0; 99.8]). Regarding predictive values, the tests yielded statistically similar estimates of positive and negative predictive values (PPV and NPV). A serial interpretation of the results of RDT and LM raised the PPVs and NPVs to >98%. Conclusions: LM and RDT afford high Se and Sp in a low P. falciparum prevalence setting. A serial combination of the tests assures high PPV and NPV estimates. These elements, coupled with the wide deployment and affordability of the tests, lend the tests useful for guiding clinical care and surveillance activities for P. falciparum within elimination settings.
Collapse
Affiliation(s)
- Marshal M. Mweu
- School of Public Health, University of Nairobi, Nairobi, Kenya
| | | | - Fixtan Njuga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Daniel Mwanga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| |
Collapse
|
24
|
Abdalla ZA, Rahma NA, Hassan EE, Abdallah TM, Hamad HE, Omer SA, Adam I. The diagnostic performance of rapid diagnostic tests and microscopy for malaria diagnosis in eastern Sudan using a nested polymerase chain reaction assay as a reference standard. Trans R Soc Trop Med Hyg 2019; 113:701-705. [DOI: 10.1093/trstmh/trz069] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/19/2019] [Accepted: 06/27/2019] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Accurate diagnosis of malaria infection is essential for successful control and management of the disease. Both microscopy and rapid diagnostic tests (RDTs) are recommended for malaria diagnosis, however, RDTs are more commonly used. The aim of the current study was to assess the performance of microscopy and RDTs in the diagnosis of Plasmodium falciparum infection using a nested polymerase chain reaction (PCR) assay as the gold standard.
Methods
A cross-sectional study was carried out in Kassala Hospital, eastern Sudan. A total of 341 febrile participants of all ages were recruited. Blood specimens were collected and malaria testing was performed using an RDT (SD Bioline Malaria Ag Pf), microscopy and nested PCR. The sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively) of microscopy and the RDT were investigated.
Results
The prevalence of P. falciparum malaria infections in this study was 22.9%, 24.3% and 26.7% by PCR, microscopy and RDT, respectively. Compared with microscopy, the RDT had slightly higher sensitivity (80.7% vs 74.3%; p=0.442), equivalent specificity (89.3% vs 90.4%), a similar PPV (69.2% vs 69.8%) and a higher NPV (94.0% vs 92.2%).
Conclusions
The diagnostic performance of the RDT was better than that of microscopy in the diagnosis of P. falciparum malaria when nested PCR was used as the gold standard.
Collapse
Affiliation(s)
| | | | - Elhashimi E Hassan
- College of Applied Medical Sciences, Najran University, Najran, Saudi Arabia
| | | | - Hadeel E Hamad
- Department of Immunology and Biotechnology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Samia A Omer
- Department of Immunology and Biotechnology, Tropical Medicine Research Institute, National Centre for Research, Khartoum, Sudan
| | - Ishag Adam
- Faculty of Medicine, University of Khartoum, PO Box 102, Khartoum, Sudan
| |
Collapse
|
25
|
Low YK, Chan J, Soraya GV, Buffet C, Abeyrathne CD, Huynh DH, Skafidas E, Kwan P, Rogerson SJ. Development of an Ultrasensitive Impedimetric Immunosensor Platform for Detection of Plasmodium Lactate Dehydrogenase. SENSORS 2019; 19:s19112446. [PMID: 31146340 PMCID: PMC6603725 DOI: 10.3390/s19112446] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/17/2019] [Accepted: 05/22/2019] [Indexed: 11/20/2022]
Abstract
Elimination of malaria is a global health priority. Detecting an asymptomatic carrier of Plasmodium parasites to receive treatment is an important step in achieving this goal. Current available tools for detection of malaria parasites are either expensive, lacking in sensitivity for asymptomatic carriers, or low in throughput. We investigated the sensitivity of an impedimetric biosensor targeting the malaria biomarker Plasmodium lactate dehydrogenase (pLDH). Following optimization of the detection protocol, sensor performance was tested using phosphate-buffered saline (PBS), and then saliva samples spiked with pLDH at various concentrations. The presence of pLDH was determined by analyzing the sensor electrical properties before and after sample application. Through comparing percentage changes in impedance magnitude, the sensors distinguished pLDH-spiked PBS from non-spiked PBS at concentrations as low as 250 pg/mL (p = 0.0008). Percentage changes in impedance magnitude from saliva spiked with 2.5 ng/mL pLDH trended higher than those from non-spiked saliva. These results suggest that these biosensors have the potential to detect concentrations of pLDH up to two logs lower than currently available best-practice diagnostic tools. Successful optimization of this sensor platform would enable more efficient diagnosis of asymptomatic carriers, who can be targeted for treatment, contributing to the elimination of malaria.
Collapse
Affiliation(s)
- Yu Kong Low
- Department of Medicine, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, 792 Elizabeth Street, Melbourne, VIC 3000, Australia.
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Victoria 3050, Australia.
| | - Jianxiong Chan
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Victoria 3050, Australia.
| | - Gita V Soraya
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Victoria 3050, Australia.
- Department of Biochemistry, Faculty of Medicine, Hasanuddin University, Makassar 90245, Indonesia.
| | - Christelle Buffet
- Department of Medicine, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, 792 Elizabeth Street, Melbourne, VIC 3000, Australia.
| | - Chathurika D Abeyrathne
- Department of Electrical and Electronic Engineering, Melbourne School of Engineering, The University of Melbourne, Victoria 3010, Australia.
| | - Duc H Huynh
- Department of Electrical and Electronic Engineering, Melbourne School of Engineering, The University of Melbourne, Victoria 3010, Australia.
| | - Efstratios Skafidas
- Department of Electrical and Electronic Engineering, Melbourne School of Engineering, The University of Melbourne, Victoria 3010, Australia.
| | - Patrick Kwan
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Victoria 3050, Australia.
| | - Stephen J Rogerson
- Department of Medicine, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, 792 Elizabeth Street, Melbourne, VIC 3000, Australia.
| |
Collapse
|
26
|
Sitali L, Miller JM, Mwenda MC, Bridges DJ, Hawela MB, Hamainza B, Chizema-Kawesha E, Eisele TP, Chipeta J, Lindtjørn B. Distribution of Plasmodium species and assessment of performance of diagnostic tools used during a malaria survey in Southern and Western Provinces of Zambia. Malar J 2019; 18:130. [PMID: 30971231 PMCID: PMC6458729 DOI: 10.1186/s12936-019-2766-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 04/04/2019] [Indexed: 11/10/2022] Open
Abstract
Background Zambia continues to make strides in reducing malaria burden through the use of proven malaria interventions and has recently pledged to eliminate malaria by 2021. Case management services have been scaled up at community level with rapid diagnostic tests (RDTs) providing antigen-based detection of falciparum malaria only. Key to national malaria elimination goals is the ability to identify, treat and eliminate all Plasmodium species. This study sought to determine the distribution of non-falciparum malaria and assess the performance of diagnostic tests for Plasmodium falciparum in Western and Southern Provinces of Zambia, two provinces planned for early malaria elimination. Methods A sub-set of individuals’ data and samples from a cross-sectional household survey, conducted during peak malaria transmission season in April and May 2017, was used. The survey collected socio-demographic information on household members and coverage of malaria interventions. Malaria testing was done on respondents of all ages using blood smears and RDTs while dried blood spots were collected on filter papers for analysis using photo-induced electron transfer polymerase chain reaction (PET-PCR). Slides were stained using Giemsa stain and examined by microscopy for malaria parasites. Results From the 1567 individuals included, the overall prevalence of malaria was 19.4% (CI 17.5–21.4) by PCR, 19.3% (CI 17.4–21.4) by RDT and 12.9% (CI 11.3–14.7) by microscopy. Using PET-PCR as the gold standard, RDTs showed a sensitivity of 75.7% (CI 70.4–80.4) and specificity of 94.2% (CI 92.8–95.4). The positive predictive value (PPV) was 75.9% (CI 70.7–80.6) and negative predictive value (NPV) was 94.1% (CI 92.1–95.4). In contrast, microscopy for sensitivity, specificity, PPV, and NPV values were 56.9% (CI 51.1–62.5), 97.7% (CI 96.7–98.5), 85.6% (CI 80.0–90.2), 90.4% (CI 88.7–91.9), respectively. Non-falciparum infections were found only in Western Province, where 11.6% of P. falciparum infections were co-infections with Plasmodium ovale or Plasmodium malariae. Conclusion From the sub-set of survey data analysed, non-falciparum species are present and occurred as mixed infections. As expected, PET-PCR was slightly more sensitive than both malaria RDTs and microscopy to detecting malaria infections.
Collapse
Affiliation(s)
- Lungowe Sitali
- Centre for International Health, Faculty of Medicine, University of Bergen, Bergen, Norway. .,Department of Biomedical Science, School of Health Sciences, University of Zambia, Lusaka, Zambia. .,School of Medicine and University Teaching Hospital Malaria Research Unit (SMUTH-MRU), Lusaka, Zambia.
| | - John M Miller
- PATH Malaria Control and Elimination Partnership in Africa (MACEPA), National Malaria Elimination Centre, Ministry of Health, Chainama Grounds, Lusaka, Zambia
| | - Mulenga C Mwenda
- PATH Malaria Control and Elimination Partnership in Africa (MACEPA), National Malaria Elimination Centre, Ministry of Health, Chainama Grounds, Lusaka, Zambia
| | - Daniel J Bridges
- PATH Malaria Control and Elimination Partnership in Africa (MACEPA), National Malaria Elimination Centre, Ministry of Health, Chainama Grounds, Lusaka, Zambia
| | - Moonga B Hawela
- National Malaria Elimination Centre, Ministry of Health, Chainama Hospital and College Grounds, Lusaka, Zambia
| | - Busiku Hamainza
- National Malaria Elimination Centre, Ministry of Health, Chainama Hospital and College Grounds, Lusaka, Zambia
| | - Elizabeth Chizema-Kawesha
- National Malaria Elimination Centre, Ministry of Health, Chainama Hospital and College Grounds, Lusaka, Zambia
| | - Thomas P Eisele
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA.,Center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA
| | - James Chipeta
- School of Medicine and University Teaching Hospital Malaria Research Unit (SMUTH-MRU), Lusaka, Zambia.,Department of Paediatrics and Child Health, University of Zambia School of Medicine, Lusaka, Zambia
| | - Bernt Lindtjørn
- Centre for International Health, Faculty of Medicine, University of Bergen, Bergen, Norway
| |
Collapse
|
27
|
Mweu MM, Wambua J, Njuga F, Bejon P, Mwanga D. Bayesian evaluation of the performance of three diagnostic tests for Plasmodium falciparum infection in a low-transmission setting in Kilifi County, Kenya. Wellcome Open Res 2019; 4:67. [PMID: 31595228 PMCID: PMC6777009 DOI: 10.12688/wellcomeopenres.15204.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/01/2019] [Indexed: 10/15/2023] Open
Abstract
Background: Central to the successful elimination of Plasmodium falciparum malaria, are tests with superior capability of diagnosing low-density parasitaemias. Empirical evidence on the performance of the commonly available diagnostics (light microscopy (LM), rapid diagnostic tests (RDT) and polymerase chain reaction (PCR)) is needed to better inform case management and surveillance activities within primary health care settings where elimination of falciparum malaria is targeted. The objective of this study was to estimate the sensitivity (Se) and specificity (Sp) and predictive values of LM, RDT and PCR tests for P. falciparum infection, while evaluating the effect of specific covariates on the accuracy of the tests. Methods: The study enrolled 1,563 children via a cross-sectional survey for asymptomatic malaria and those presenting with symptomatic malaria to the Ngerenya dispensary, Kilifi County between March and December 2014. A Bayesian latent class model (BLCM) was fitted to the participants' diagnostic data obtained from blood samples that were screened for the presence of P. falciparum using the three tests. Results: The PCR assay registered a higher Se (97.6% [92.0; 99.7]) than LM (84.0% [74.8; 91.0]) but similar to RDT (92.2% [84.4; 97.0]). However, the assay showed a similar Sp (98.9% [98.2; 99.4]) to both RDT (99.4% [98.9; 99.7]) and LM (99.5% [99.0; 99.8]). Regarding predictive values, the tests yielded statistically similar estimates of Positive and negative predictive values (PPV and NPV). A serial interpretation of the results of RDT and LM raised the PPVs and NPVs to >98%. Conclusions: LM and RDT tests afford high Se and Sp in a low P. falciparum prevalence setting. A serial combination of the tests assures high PPV and NPV estimates. These elements, coupled with the wide deployment and affordability of the tests, lend the tests useful for guiding clinical care and surveillance activities for P. falciparum within elimination settings.
Collapse
Affiliation(s)
- Marshal M. Mweu
- School of Public Health, University of Nairobi, Nairobi, Kenya
| | | | - Fixtan Njuga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Daniel Mwanga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| |
Collapse
|
28
|
Mfuh KO, Achonduh-Atijegbe OA, Bekindaka ON, Esemu LF, Mbakop CD, Gandhi K, Leke RGF, Taylor DW, Nerurkar VR. A comparison of thick-film microscopy, rapid diagnostic test, and polymerase chain reaction for accurate diagnosis of Plasmodium falciparum malaria. Malar J 2019; 18:73. [PMID: 30866947 PMCID: PMC6416847 DOI: 10.1186/s12936-019-2711-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 03/06/2019] [Indexed: 11/18/2022] Open
Abstract
Background Accurate diagnosis of malaria is important for effective disease management and control. In Cameroon, presumptive clinical diagnosis, thick-film microscopy (TFM), and rapid diagnostic tests (RDT) are commonly used to diagnose cases of Plasmodium falciparum malaria. However, these methods lack sensitivity to detect low parasitaemia. Polymerase chain reaction (PCR), on the other hand, enhances the detection of sub-microscopic parasitaemia making it a much-needed tool for epidemiological surveys, mass screening, and the assessment of interventions for malaria elimination. Therefore, this study sought to determine the frequency of cases missed by traditional methods that are detected by PCR. Methods Blood samples, collected from 551 febrile Cameroonian patients between February 2014 and February 2015, were tested for P. falciparum by microscopy, RDT and PCR. The hospital records of participants were reviewed to obtain data on the clinical diagnosis made by the health care worker. Results The prevalence of malaria by microscopy, RDT and PCR was 31%, 45%, and 54%, respectively. However, of the 92% of participants diagnosed as having clinical cases of malaria by the health care worker, 38% were malaria-negative by PCR. PCR detected 23% and 12% more malaria infections than microscopy and RDT, respectively. A total of 128 (23%) individuals had sub-microscopic infections in the study population. The sensitivity of microscopy, RDT, and clinical diagnosis was 57%, 78% and 100%; the specificity was 99%, 94%, and 17%; the positive predictive values were 99%, 94%, and 59%; the negative predictive values were 66%, 78%, and 100%, respectively. Thus, 41% of the participants clinically diagnosed as having malaria had fever caused by other pathogens. Conclusions Malaria diagnostic methods, such as TFM and RDT missed 12–23% of malaria cases detected by PCR. Therefore, traditional diagnostic approaches (TFM, RDT and clinical diagnosis) are not adequate when accurate epidemiological data are needed for monitoring malaria control and elimination interventions.
Collapse
Affiliation(s)
- Kenji O Mfuh
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA.,Biotechnology Center, University of Yaoundé I, Yaoundé, Cameroon
| | | | | | - Livo F Esemu
- Biotechnology Center, University of Yaoundé I, Yaoundé, Cameroon
| | - Calixt D Mbakop
- National Medical Research Institute (IMPM), Yaoundé, Cameroon
| | - Krupa Gandhi
- Biostatistics Core Facility Department of Complementary & Integrative Medicine, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA
| | - Rose G F Leke
- Biotechnology Center, University of Yaoundé I, Yaoundé, Cameroon
| | - Diane W Taylor
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA
| | - Vivek R Nerurkar
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA. .,Pacific Center for Emerging Infectious Diseases Research, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA.
| |
Collapse
|
29
|
Teh RN, Sumbele IUN, Asoba Nkeudem G, Meduke DN, Ojong ST, Kimbi HK. Concurrence of CareStart™ Malaria HRP2 RDT with microscopy in population screening for Plasmodium falciparum infection in the Mount Cameroon area: predictors for RDT positivity. Trop Med Health 2019; 47:17. [PMID: 30867636 PMCID: PMC6397448 DOI: 10.1186/s41182-019-0145-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 02/20/2019] [Indexed: 11/10/2022] Open
Abstract
Background Malaria remains a diagnostic challenge in many endemic communities. Although rapid diagnostic tests (RDTs) are presently widely used for malaria diagnosis, there is a dearth of information on post-marketing surveillance on its efficacy in Cameroon. The present study evaluated the performance characteristics of CareStart™ Malaria HRP2 (histidine-rich protein 2) antigen (Ag) RDT in diagnosing Plasmodium falciparum infection in the Mount Cameroon area and predictors associated with RDT positivity. Methods The CareStart™ Malaria HRP2 Plasmodium falciparum (G0141) Ag RDT was evaluated in a cross-sectional community-based survey involving 491 children of both sexes aged 6 months to 14 years between April and May 2018. Malaria parasitaemia was confirmed by light microscopy. Sensitivity (Se), specificity (Sp), positive (PPV) and negative (NPV) predictive values of the RDT, and the corresponding accuracy and Kappa value (κ) were determined using microscopy as the gold standard. Haemoglobin (Hb) concentration was obtained using an auto-haematology analyser. Results were compared using the chi-square test and associations between predictor variables, and RDT results were assessed using logistic regression analysis. Results Microscopically confirmed malaria parasite prevalence was 27.7%, and geometric mean density was 187 parasites/μL of blood (range 70-1162). Se, Sp, PPV, NPV and accuracy were 82.4, 76.6, 57.4, 91.9 and 78.2%, respectively. Sensitivity depended on parasitaemia and reached 96.1% at densities ≥ 200 parasites/μL of blood. The accuracy of malaria parasitaemia (as assessed by the area under the receiver operating characteristic curve) to predict malaria by RDT was 75.4% (95% CI 70.6-80.1). The agreement between microscopy and RDT was moderate (κ = 0.52). RDT positivity was significantly associated with fever (P < 0.001), children less than 5 years (P = 0.02), history of fever within a month (P < 0.001) and anaemia (P = 0.002). Conclusion The overall concurrence of CareStart™ Malaria HRP2 pf Ag RDT with microscopy in the detection of P. falciparum infection is moderate and is most useful at parasitaemia ≥ 200 parasites/μL of blood and presentation with fever. While RDT is effective as a diagnostic test for confirmation of clinical cases of malaria, its applications in population screening with a higher proportion of asymptomatic cases are limited.
Collapse
Affiliation(s)
- Rene Ning Teh
- 1Department of Zoology and Animal Physiology, University of Buea, Buea, Cameroon
| | | | - Gillian Asoba Nkeudem
- 1Department of Zoology and Animal Physiology, University of Buea, Buea, Cameroon.,2Department of Social Economy and Family Management, Higher Technical Teachers' Training College, University of Buea, P.O. Box 249, Kumba, Cameroon
| | - Derick Ndelle Meduke
- 1Department of Zoology and Animal Physiology, University of Buea, Buea, Cameroon
| | - Samuel Takang Ojong
- 1Department of Zoology and Animal Physiology, University of Buea, Buea, Cameroon.,3Clinical Diagnostic Laboratory, University of Buea, Buea, Cameroon
| | - Helen Kuokuo Kimbi
- 1Department of Zoology and Animal Physiology, University of Buea, Buea, Cameroon.,4Department of Medical Laboratory Sciences, The University of Bamenda, Bambili, Cameroon
| |
Collapse
|
30
|
Paper-based microfluidics for DNA diagnostics of malaria in low resource underserved rural communities. Proc Natl Acad Sci U S A 2019; 116:4834-4842. [PMID: 30782834 PMCID: PMC6421471 DOI: 10.1073/pnas.1812296116] [Citation(s) in RCA: 179] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Populations living in remote rural communities would benefit from rapid, highly sensitive molecular, DNA-based diagnostics to inform the correct and timely treatment of infectious diseases. Such information is also becoming increasingly relevant in global efforts for disease elimination, where the testing of asymptomatic patients is now seen as being important for the identification of disease reservoirs. However, healthcare workers face practical and logistical problems in the implementation of such tests, which often involve complex instrumentation and centralized laboratories. Here we describe innovations in paper microfluidics that enable low-cost, multiplexed DNA-based diagnostics for malaria, delivered, in a first-in-human study, in schools in rural Uganda. Rapid, low-cost, species-specific diagnosis, based upon DNA testing, is becoming important in the treatment of patients with infectious diseases. Here, we demonstrate an innovation that uses origami to enable multiplexed, sensitive assays that rival polymerase chain reactions (PCR) laboratory assays and provide high-quality, fast precision diagnostics for malaria. The paper-based microfluidic technology proposed here combines vertical flow sample-processing steps, including paper folding for whole-blood sample preparation, with an isothermal amplification and a lateral flow detection, incorporating a simple visualization system. Studies were performed in village schools in Uganda with individual diagnoses being completed in <50 min (faster than the standard laboratory-based PCR). The tests, which enabled the diagnosis of malaria species in patients from a finger prick of whole blood, were both highly sensitive and specific, detecting malaria in 98% of infected individuals in a double-blind first-in-human study. Our method was more sensitive than other field-based, benchmark techniques, including optical microscopy and industry standard rapid immunodiagnostic tests, both performed by experienced local healthcare teams (which detected malaria in 86% and 83% of cases, respectively). All assays were independently validated using a real-time double-blinded reference PCR assay. We not only demonstrate that advanced, low-cost DNA-based sensors can be implemented in underserved communities at the point of need but also highlight the challenges associated with developing and implementing new diagnostic technologies in the field, without access to laboratories or infrastructure.
Collapse
|
31
|
Bahk YY, Park SH, Lee W, Jin K, Ahn SK, Na BK, Kim TS. Comparative Assessment of Diagnostic Performances of Two Commercial Rapid Diagnostic Test Kits for Detection of Plasmodium spp. in Ugandan Patients with Malaria. THE KOREAN JOURNAL OF PARASITOLOGY 2018; 56:447-452. [PMID: 30419730 PMCID: PMC6243188 DOI: 10.3347/kjp.2018.56.5.447] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Accepted: 09/05/2018] [Indexed: 11/23/2022]
Abstract
Prompt diagnosis of malaria cases with rapid diagnostic tests (RDTs) has been widely adopted as an effective malaria diagnostic tool in many malaria endemic countries, primarily due to their easy operation, fast result output, and straightforward interpretation. However, there has been controversy about the diagnostic accuracy of RDTs. This study was conducted to evaluate the diagnostic performances of the 2 commercially available malaria RDT kits, RapiGEN Malaria Ag Pf/Pv (pLDH/pLDH) and Asan EasyTestTM Malaria Ag Pf/Pv (HRP-2/pLDH) for their abilities to detect Plasmodium species in blood samples collected from Ugandan patients with malaria. To evaluate the diagnostic performances of these 2 RDT kits, 229 blood samples were tested for malaria infection by microscopic examination and a species-specific nested polymerase chain reaction. The detection sensitivities for P. falciparum of Malaria Ag Pf/Pv (pLDH/pLDH) and Asan EasyTestTM Malaria Ag Pf/Pv (HRP-2/pLDH) were 87.83% and 89.57%, respectively. The specificities of the 2 RDTs were 100% for P. falciparum and mixed P. falciparum/P. vivax infections. These results suggest that the 2 RDT kits showed reasonable levels of diagnostic performances for detection of the malaria parasites from Ugandan patients. However, neither kit could effectively detect P. falciparum infections with low parasitaemia (<500 parasites/μl).
Collapse
Affiliation(s)
- Young Yil Bahk
- Department of Biotechnology, College of Biomedical and Health Science, Konkuk University, Chungju 27478, Korea
| | - Seo Hye Park
- Department of Tropical Medicine, Inha University College of Medicine, Incheon 22212, Korea
| | - Woojoo Lee
- Department of Statistics, Inha University College of Natural Sciences, Incheon 22212, Korea
| | - Kyoung Jin
- Korea Health Evaluation Institute, Sahmyook University, Seoul 01795, Korea
| | - Seong Kyu Ahn
- Department of Tropical Medicine, Inha University College of Medicine, Incheon 22212, Korea
| | - Byoung-Kuk Na
- Korea Health Evaluation Institute, Sahmyook University, Seoul 01795, Korea
| | - Tong-Soo Kim
- Department of Statistics, Inha University College of Natural Sciences, Incheon 22212, Korea
| |
Collapse
|
32
|
Kitutu FE, Wamani H, Selling KE, Katabazi FA, Kuteesa RB, Peterson S, Kalyango JN, Mårtensson A. Can malaria rapid diagnostic tests by drug sellers under field conditions classify children 5 years old or less with or without Plasmodium falciparum malaria? Comparison with nested PCR analysis. Malar J 2018; 17:365. [PMID: 30326926 PMCID: PMC6192306 DOI: 10.1186/s12936-018-2508-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 10/06/2018] [Indexed: 01/02/2023] Open
Abstract
Background Malaria rapid diagnostic tests (RDTs) available as dipsticks or strips, are simple to perform, easily interpretable and do not require electricity nor infrastructural investment. Correct interpretation of and compliance with the RDT results is a challenge to drug sellers. Thus, drug seller interpretation of RDT strips was compared with laboratory scientist re-reading, and PCR analysis of Plasmodium DNA extracted from RDT nitrocellulose strips and fast transient analysis (FTA) cards. Malaria RDT cassettes were also assessed as a potential source of Plasmodium DNA. Methods A total of 212 children aged between 2 and 60 months, 199 of whom had complete records at two study drug shops in south western Uganda participated in the study. Duplicate 5 μL samples of capillary blood were picked from the 212 children, dispensed onto the sample well of the CareStart™ Pf-HRP2 RDT cassette and a FTA, Whatman™ 3MM filter paper in parallel. The RDT strip was interpreted by the drug seller within 15–20 min, visually re-read centrally by laboratory scientist and from it; Plasmodium DNA was recovered and detected by PCR, and compared with FTA recovered P. falciparum DNA PCR detection. Results Malaria positive samples were 62/199 (31.2%, 95% CI 24.9, 38.3) by drug seller interpretation of RDT strip, 59/212 (27.8%, 95% CI 22.2, 34.3) by laboratory scientist, 55/212 (25.9%, 95% CI 20.0, 32.6) by RDT nitrocellulose strip PCR and 64/212 (30.2%, 95% CI 24.4, 37.7). The overall agreement between the drug seller interpretation and laboratory scientist re-reading of the RDT strip was 93.0% with kappa value of 0.84 (95% CI 0.75, 0.92). The drug seller compliance with the reported RDT results was 92.5%. The performance of the three diagnostic strategies compared with FTA-PCR as the gold standard had sensitivity between 76.6 and 86.9%, specificity above 90%, positive predictive values ranging from 79.0 to 89.8% and negative predictive values above 90%. Conclusion Drug sellers can use RDTs in field conditions and achieve acceptable accuracy for malaria diagnosis, and they comply with the RDT results. Plasmodium DNA can be recovered from RDT nitrocellulose strips even in the context of drug shops. Future malaria surveillance and diagnostic quality control studies with RDT cassette as a source of Plasmodium DNA are recommended. Electronic supplementary material The online version of this article (10.1186/s12936-018-2508-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Freddy Eric Kitutu
- Department of Women's and Children's Health, International Maternal and Child Health (IMCH), Uppsala University, Uppsala, Sweden. .,Pharmacy Department, Makerere University College of Health Sciences, Kampala, Uganda.
| | - Henry Wamani
- School of Public Health, Makerere University College of Health Sciences, Kampala, Uganda
| | - Katarina Ekholm Selling
- Department of Women's and Children's Health, International Maternal and Child Health (IMCH), Uppsala University, Uppsala, Sweden
| | - Fred Ashaba Katabazi
- Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, Uganda
| | - Ronald Bisaso Kuteesa
- Infectious Disease Institute, Makerere University College of Health Sciences, Kampala, Uganda
| | - Stefan Peterson
- Department of Women's and Children's Health, International Maternal and Child Health (IMCH), Uppsala University, Uppsala, Sweden.,School of Public Health, Makerere University College of Health Sciences, Kampala, Uganda.,UNICEF, Health Section, 3 UN Plaza, New York, NY, 10017, USA
| | - Joan Nakayaga Kalyango
- Pharmacy Department, Makerere University College of Health Sciences, Kampala, Uganda.,Clinical Epidemiology and Biostatistics Unit, Makerere University College of Health Sciences, Kampala, Uganda
| | - Andreas Mårtensson
- Department of Women's and Children's Health, International Maternal and Child Health (IMCH), Uppsala University, Uppsala, Sweden
| |
Collapse
|
33
|
Oldenburg CE, Guerin PJ, Berthé F, Grais RF, Isanaka S. Malaria and Nutritional Status Among Children With Severe Acute Malnutrition in Niger: A Prospective Cohort Study. Clin Infect Dis 2018; 67:1027-1034. [PMID: 29522089 PMCID: PMC6137121 DOI: 10.1093/cid/ciy207] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 03/06/2018] [Indexed: 11/14/2022] Open
Abstract
Background The relationship between malaria infection and nutritional status is complex. Previous studies suggest malaria may increase the incidence and severity of malnutrition, while malnutrition may increase the risk of malaria infection. Here, we report bidirectional associations between malaria and nutritional status among children with uncomplicated severe acute malnutrition (SAM). Methods This study is a secondary analysis of a randomized, controlled trial for the treatment of uncomplicated SAM in Niger. Children aged 6-59 months were enrolled and followed for 12 weeks. Malaria infection was assessed using an histidine-rich protein 2 (HRP2) rapid diagnostic test at admission and at any follow-up visit with fever. We assessed the association of nutritional status at admission on malaria incidence using Cox proportional hazards regression and malaria infection at admission on nutritional recovery and weight and height gain using linear regression. Results Of 2399 children included in the analysis, 1327 (55.3%) were infected with malaria at admission. Malaria incidence was 12.1 cases/100 person-months among those without malaria infection at admission. Nutritional status at admission was not associated with malaria incidence. Children with malaria infection at admission and subsequently treated with an artemisinin-based combination therapy had increased weight gain (0.38 g/kg/day; 95% confidence interval [CI], 0.07 to 0.69) and reduced height gain (-0.002 mm/day; 95% CI, -0.004 to -0.0008). Conclusions Malaria infection was common among children treated for uncomplicated SAM. Malaria infection may impair height gain. Proper medical and nutritional management should be ensured to prevent adverse effects of malaria infection. Clinical Trials Registration NCT01613547.
Collapse
Affiliation(s)
- Catherine E Oldenburg
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
| | - Philippe J Guerin
- WorldWide Antimalarial Resistance Network, University of Oxford, United Kingdom
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, United Kingdom
| | | | | | - Sheila Isanaka
- Department of Research, Epicentre, Paris, France
- Departments of Nutrition and Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| |
Collapse
|
34
|
Rapid design and fielding of four diagnostic technologies in Sierra Leone, Thailand, Peru, and Australia: Successes and challenges faced introducing these biosensors. SENSING AND BIO-SENSING RESEARCH 2018. [DOI: 10.1016/j.sbsr.2018.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
35
|
Nderu D, Kimani F, Thiong'o K, Akinyi M, Karanja E, Meyer CG, Velavan TP. PfHRP2-PfHRP3 diversity among Kenyan isolates and comparative evaluation of PfHRP2/pLDH malaria RDT with microscopy and nested PCR methodologies. Parasitol Int 2018; 67:793-799. [PMID: 30138695 DOI: 10.1016/j.parint.2018.08.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/08/2018] [Accepted: 08/18/2018] [Indexed: 01/24/2023]
Abstract
Rapid diagnostic tests (RDT) are valuable tools that support prudent and timely use of antimalarial drugs, particularly if reliable microscopy is not available. However, the performance and reliability of these tests vary between and within geographical regions. The present study evaluated the performance of routine malaria RDT in Kenyan febrile patients in Busia County, Kenya. A cross sectional study design was employed to recruit febrile patients attending health facilities between August and November 2016. A total of 192 febrile patients who were slide positive and negative were evaluated for their infection status by nested PCR and RDTs (PfHRP2/pLDH). In addition, P. falciparum diversity of the histidine-rich proteins 2 and 3, that influences the RDT test results were determined. All individuals were P. falciparum positive. Among the investigated 192 febrile patients, 76 (40%) were positive by microscopy, 101 (53%) by RDTs and 80 (42%) were PCR positive. The performance of the CareStart™ HRP2/pLDH (pf) RDTs was better than microscopy (Sensitivity 94%; Specificity 75%) and Nucleic acid testing (sensitivity 95%, specificity 77%) with high negative predictive values, indicating the suitability of the RDT in routine practice. Specific pfhrp2/pfhrp3 deletions shown to associate with RDT false negativity was not observed. However, high genetic diversity among pfhrp2 gene was observed. Eleven new PfHRP2 and nine PfHRP3 repeats were observed. False positivity by microscopy and under reporting of infections may thus be a barrier in malaria control and elimination programs. The HRP2/pLDH(Pf) based RDT yet demonstrate to be an effective tool for malaria surveillance program.
Collapse
Affiliation(s)
- David Nderu
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany; School of Health Sciences, Kirinyaga University, 10300 Kerugoya, Kenya
| | - Francis Kimani
- Center for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Kelvin Thiong'o
- Center for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Maureen Akinyi
- Center for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Evaline Karanja
- Department of Biochemistry and Biotechnology, School of Biological and Life Sciences, Technical University of Kenya, Nairobi, Kenya
| | - Christian G Meyer
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany; Vietnamese-German Centre for Medical Research (VG-CARE), Hanoi, Viet Nam; Faculty of Medicine, Duy Tan University, Da Nang, Viet Nam
| | - Thirumalaisamy P Velavan
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany; Vietnamese-German Centre for Medical Research (VG-CARE), Hanoi, Viet Nam; Faculty of Medicine, Duy Tan University, Da Nang, Viet Nam; Fondation Congolaise pour la Recherche Médicale, Brazzaville, Congo.
| |
Collapse
|
36
|
Presumptive Treatment of Malaria in Ghana: Was It Ever Useful? Evidence from the Kassena-Nankana District of Northern Ghana. Malar Res Treat 2018; 2018:3408089. [PMID: 30112162 PMCID: PMC6077512 DOI: 10.1155/2018/3408089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 06/13/2018] [Accepted: 06/25/2018] [Indexed: 11/17/2022] Open
Abstract
Background The WHO currently advocates parasitological confirmation of malaria before treatment is commenced. However, many arguments have emerged both for and against this new position. To contribute to the debate, this secondary data analysis was conducted to determine the likelihood of malaria parasitaemia in a child presenting with fever, vomiting, or cough in the Kassena-Nankana District. Methods The dataset for this analysis was generated during a study to assess the incidence and risk factors for paediatric rotavirus diarrhoea in the Kassena-Nankana District. Over a two-year period, trained field staff recruited 2086 subjects with episodes of diarrhoea aged 24 months or below into the study. A standard case report form was used to collect data on histories of illness, symptoms, vaccination, and anthropometry. Blood smears were tested for malaria parasites. The data set generated was obtained, cleaned, and analysed using Epi Info version 7.1.1.14 statistical software. Results Of the 2086 subjects recruited, 2078 had blood smears done and 54.0% had malaria parasites. Fever and vomiting appeared to be associated with parasitaemia with odds ratios of 1.9 (95% CI: 1.5586–2.2370) and 1.2 (95% CI: 1.0352–1.4697), respectively. Cough however appeared protective with an odds ratio of 0.8 (95% CI: 0.6910–0.9765). The odds of parasitaemia appeared to increase where a child presented with more than one symptom. Conclusion Nearly half (46%) of the subjects in this study presented with symptoms but had no malaria. Presumptive treatment of malaria may therefore be useful in situations where diagnostic tests are not readily available, its routine practice should however not be encouraged.
Collapse
|
37
|
Ita OI, Otu AA, Onyedibe K, Iwuafor AA, Banwat E, Egah DZ. A diagnostic performance evaluation of rapid diagnostic tests and microscopy for malaria diagnosis using nested polymerase chain reaction as reference standard in a tertiary hospital in Jos, Nigeria. Trans R Soc Trop Med Hyg 2018; 112:436-442. [DOI: 10.1093/trstmh/try071] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 06/19/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Okokon I Ita
- Department of Medical Microbiology and Parasitology, University of Calabar, Calabar, Cross River State
| | - Akaninyene A Otu
- Department of Internal Medicine, University of Calabar, Calabar, Cross River State, Nigeria
- National Aspergillosis Centre, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Kenneth Onyedibe
- Department of Medical Microbiology and Parasitology, University of Jos, Plateau State, Nigeria
| | - Anthony A Iwuafor
- Department of Medical Microbiology and Parasitology, University of Calabar, Calabar, Cross River State
| | - Edmund Banwat
- Department of Medical Microbiology and Parasitology, University of Jos, Plateau State, Nigeria
| | - Daniel Z Egah
- Department of Medical Microbiology and Parasitology, University of Jos, Plateau State, Nigeria
| |
Collapse
|
38
|
Robinson ML, Kadam D, Khadse S, Balasubramanian U, Raichur P, Valvi C, Marbaniang I, Kanade S, Sachs J, Basavaraj A, Bharadwaj R, Kagal A, Kulkarni V, Zenilman J, Nelson G, Manabe YC, Kinikar A, Gupta A, Mave V. Vector-Borne Disease is a Common Cause of Hospitalized Febrile Illness in India. Am J Trop Med Hyg 2018; 98:1526-1533. [PMID: 29582731 DOI: 10.4269/ajtmh.17-0571] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Acute febrile illness (AFI) is a major cause of morbidity and mortality in India and other resource-limited settings, yet systematic etiologic characterization of AFI has been limited. We prospectively enrolled adults (N = 970) and children (age 6 months to 12 years, N = 755) admitted with fever from the community to Sassoon General Hospital in Pune, India, from July 2013 to December 2015. We systematically obtained a standardized clinical history, basic laboratory testing, and microbiologic diagnostics on enrolled participants. Results from additional testing ordered by treating clinicians were also recorded. A microbiological diagnosis was found in 549 (32%) participants; 211 (12%) met standardized case definitions for pneumonia and meningitis without an identified organism; 559 (32%) were assigned a clinical diagnosis in the absence of a confirmed diagnosis; and 406 (24%) had no diagnosis. Vector-borne diseases were the most common cause of AFI in adults including dengue (N = 188, 19%), malaria (N = 74, 8%), chikungunya (N = 15, 2%), and concurrent mosquito-borne infections (N = 23, 2%) occurring most frequently in the 3 months after the monsoon. In children, pneumonia was the most common cause of AFI (N = 214, 28%) and death. Bacteremia was found in 68 (4%) participants. Central nervous system infections occurred in 58 (6%) adults and 64 (8%) children. Etiology of AFI in India is diverse, highly seasonal, and difficult to differentiate on clinical grounds alone. Diagnostic strategies adapted for season and age may reduce diagnostic uncertainty and identify causative organisms in treatable, fatal causes of AFI.
Collapse
Affiliation(s)
- Matthew L Robinson
- Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India.,Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Dileep Kadam
- Byramjee Jeejeebhoy Government Medical College, Pune, India.,Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Sandhya Khadse
- Byramjee Jeejeebhoy Government Medical College, Pune, India.,Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Usha Balasubramanian
- Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Priyanka Raichur
- Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Chhaya Valvi
- Byramjee Jeejeebhoy Government Medical College, Pune, India.,Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Ivan Marbaniang
- Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Savita Kanade
- Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Jonathan Sachs
- Tulane University School of Medicine, New Orleans, Louisiana
| | - Anita Basavaraj
- Byramjee Jeejeebhoy Government Medical College, Pune, India.,Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Renu Bharadwaj
- Byramjee Jeejeebhoy Government Medical College, Pune, India.,Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Anju Kagal
- Byramjee Jeejeebhoy Government Medical College, Pune, India.,Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Vandana Kulkarni
- Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | | | - George Nelson
- Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Yukari C Manabe
- Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Aarti Kinikar
- Byramjee Jeejeebhoy Government Medical College, Pune, India.,Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Amita Gupta
- Johns Hopkins University School of Medicine, Baltimore, Maryland.,Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India
| | - Vidya Mave
- Byramjee Jeejeebhoy Government Medical College-Johns Hopkins University Clinical Research Site, Pune, India.,Johns Hopkins University School of Medicine, Baltimore, Maryland
| |
Collapse
|
39
|
The WHO recommendation of home fortification of foods with multiple-micronutrient powders in children under 2 years of age and its effectiveness on anaemia and weight: a pragmatic cluster-randomized controlled trial. Public Health Nutr 2018; 21:1350-1358. [PMID: 29352829 DOI: 10.1017/s1368980017003858] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To assess under real community settings the effectiveness of the WHO strategy of home fortification of foods (HFF) with multiple-micronutrient powders on Hb change, anaemia and weight in children. DESIGN A pragmatic cluster-randomized controlled trial. SETTING Forty villages in the Nioro Circle in Mali and 722 children aged 6-23 months were randomized to the intervention or control group. The intervention consisted of a daily dose of multiple-micronutrient powder for 3 months; in the control group, no supplement was given. In both groups, mothers received group education on child complementary feeding. Changes in weight, Hb concentration and anaemia were assessed as primary outcomes at baseline and 3 months. The HFF effect was determined using regression analyses and quantile regression with standard errors taking account of the cluster design. SUBJECTS Children aged 6-23 months. RESULTS Overall prevalence of anaemia in the sample was high: 90 %. HFF provided a modest but statistically significant Hb change v. no intervention (0·50 v. 0·09 g/dl, P=0·023). Prevalence of anaemia changed little: 91·3-85·8 % (P=0·04) in the intervention group v. 88·1-87·5 % % (P=0·86) in the control group. Proportion of severe anaemia was reduced by 84 % (from 9·8 to 1·6 %) in the intervention group, but increased in the control group (from 8·5 to 10·8 %). No effect was observed on weight. CONCLUSIONS The WHO HFF strategy to fight anaemia showed a modest change on Hb concentration and significantly reduced the rate of severe anaemia.
Collapse
|
40
|
Morang'a C, Ayieko C, Awinda G, Achilla R, Moseti C, Ogutu B, Waitumbi J, Wanja E. Stabilization of RDT target antigens present in dried Plasmodium falciparum-infected samples for validating malaria rapid diagnostic tests at the point of care. Malar J 2018; 17:10. [PMID: 29310651 PMCID: PMC5759799 DOI: 10.1186/s12936-017-2155-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 12/23/2017] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Malaria rapid diagnostic tests (RDTs) are a great achievement in implementation of parasite based diagnosis as recommended by World Health Organization. A major drawback of RDTs is lack of positive controls to validate different batches/lots at the point of care. Dried Plasmodium falciparum-infected samples with the RDT target antigens have been suggested as possible positive control but their utility in resource limited settings is hampered by rapid loss of activity over time. METHODS This study evaluated the effectiveness of chemical additives to improve long term storage stability of RDT target antigens (HRP2, pLDH and aldolase) in dried P. falciparum-infected samples using parasitized whole blood and culture samples. Samples were treated with ten selected chemical additives mainly sucrose, trehalose, LDH stabilizer and their combinations. After baseline activity was established, the samples were air dried in bio-safety cabinet and stored at room temperatures (~ 25 °C). Testing of the stabilized samples using SD Bioline, BinaxNOW, CareStart, and First Response was done at intervals for 53 weeks. RESULTS Stability of HRP2 at ambient temperature was reported at 21-24 weeks while that of PAN antigens (pLDH and aldolase) was 2-18 weeks of storage at all parasite densities. The ten chemical additives increased the percentage stability of HRP2 and PAN antigens. Sucrose alone and its combinations with Alsever's solution or biostab significantly increased stability of HRP2 by 56% at 2000 p/µL (p < 0.001). Trehalose and its combinations with biostab, sucrose or glycerol significantly increased stability of HRP2 by 57% (p < 0.001). Unlike sucrose, the stability of the HRP2 was significantly retained by trehalose at lower concentrations (500, and 200 p/µL). Trehalose in combination biostab stabilizer increased the percentage stability of PAN antigens by 42, and 32% at 2000 and 500 p/µL respectively (p < 0.01). This was also the chemical combination with the shortest reconstitution time (~ < 20 min). CONCLUSIONS These findings confirm that stabilizing RDT target antigens in dried P. falciparum-infected samples using chemical additives provides field-stable positive controls for malaria RDTs.
Collapse
Affiliation(s)
- Collins Morang'a
- Maseno University, P.O Box Private Bag, Maseno, Kenya. .,United States Army Medical Research Directorate, P.O Box 54, Kisumu, 40100, Kenya.
| | - Cyrus Ayieko
- Maseno University, P.O Box Private Bag, Maseno, Kenya
| | - George Awinda
- United States Army Medical Research Directorate, P.O Box 54, Kisumu, 40100, Kenya
| | - Rachel Achilla
- United States Army Medical Research Directorate, P.O Box 54, Kisumu, 40100, Kenya
| | - Caroline Moseti
- United States Army Medical Research Directorate, P.O Box 54, Kisumu, 40100, Kenya
| | - Bernhards Ogutu
- Kenya Medical Research Institute, P.O. Box 54840-00200, Nairobi, Kenya
| | - John Waitumbi
- United States Army Medical Research Directorate, P.O Box 54, Kisumu, 40100, Kenya
| | - Elizabeth Wanja
- United States Army Medical Research Directorate-Armed Forces Research Institute of Medical Sciences, Bangkok, 10400, Thailand
| |
Collapse
|
41
|
Multiplex real-time PCR using temperature sensitive primer-supplying hydrogel particles and its application for malaria species identification. PLoS One 2018; 13:e0190451. [PMID: 29293604 PMCID: PMC5749795 DOI: 10.1371/journal.pone.0190451] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 12/14/2017] [Indexed: 11/19/2022] Open
Abstract
Real-time PCR, also called quantitative PCR (qPCR), has been powerful analytical tool for detection of nucleic acids since it developed. Not only for biological research but also for diagnostic needs, qPCR technique requires capacity to detect multiple genes in recent years. Solid phase PCR (SP-PCR) where one or two directional primers are immobilized on solid substrates could analyze multiplex genetic targets. However, conventional SP-PCR was subjected to restriction of application for lack of PCR efficiency and quantitative resolution. Here we introduce an advanced qPCR with primer-incorporated network (PIN). One directional primers are immobilized in the porous hydrogel particle by covalent bond and the other direction of primers are temporarily immobilized at so-called 'Supplimers'. Supplimers released the primers to aqueous phase in the hydrogel at the thermal cycling of PCR. It induced the high PCR efficiency over 92% with high reliability. It reduced the formation of primer dimers and improved the selectivity of qPCR thanks to the strategy of 'right primers supplied to right place only'. By conducting a six-plex qPCR of 30 minutes, we analyzed DNA samples originated from malaria patients and successfully identified malaria species in a single reaction.
Collapse
|
42
|
Oyet C, Roh ME, Kiwanuka GN, Orikiriza P, Wade M, Parikh S, Mwanga-Amumpaire J, Boum Y. Evaluation of the Deki Reader™, an automated RDT reader and data management device, in a household survey setting in low malaria endemic southwestern Uganda. Malar J 2017; 16:449. [PMID: 29115991 PMCID: PMC5678817 DOI: 10.1186/s12936-017-2094-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 10/28/2017] [Indexed: 11/24/2022] Open
Abstract
Background Early diagnosis of suspected malaria cases with a rapid diagnostic test (RDT) has been shown to be an effective malaria control tool used in many resource-constrained settings. However, poor quality control and quality assurance hinder the accurate reporting of malaria diagnoses. Recent use of a portable, battery operated RDT reader (Deki Reader™, Fio Corporation) has shown to have high agreement with visual inspection across diverse health centre settings, however evidence of its feasibility and usability during cross sectional surveys are limited. This study aimed to evaluate the performance of the Deki Reader™ in a cross-sectional survey of children from southwestern Uganda. Methods A two-stage, stratified cluster sampling survey was conducted between July and October 2014 in three districts of southwestern Uganda, with varying malaria transmission intensities. A total of 566 children aged 6–59 months were included in the analysis. Blood samples were collected and tested for malaria using: the SD Bioline Malaria Ag Pf/Pan RDT and microscopy. Results were compared between visual inspection of the RDT and by the Deki Reader™. Diagnostic performance of both methods were compared to gold-standard microscopy. Results The sensitivity and specificity of the Deki Reader™ was 94.1% (95% CI 69.2–99.6%) and 95.6% (95% CI 93.4–97.1%), respectively. The overall percent agreement between the Deki Reader™ and visual RDT inspection was 98.9% (95% CI 93.2–99.8), with kappa statistic of 0.92 (95% CI 0.85–0.98). Conclusions The findings from this study suggest that the Deki Reader™ is comparable to visual inspection and performs well in detecting microscopy-positive Plasmodium falciparum cases in a household survey setting. However, the reader’s performance was highly dependent on ensuring adequate battery life and a work environment free of dirt particles.
Collapse
Affiliation(s)
- Caesar Oyet
- Mbarara University of Science and Technology, P.O. Box 1410, Mbarara, Uganda.
| | - Michelle E Roh
- Yale School of Public Health, 60 College Street, New Haven, CT, 06520, USA
| | - Gertrude N Kiwanuka
- Mbarara University of Science and Technology, P.O. Box 1410, Mbarara, Uganda
| | | | - Martina Wade
- Yale School of Public Health, 60 College Street, New Haven, CT, 06520, USA
| | - Sunil Parikh
- Yale School of Public Health, 60 College Street, New Haven, CT, 06520, USA
| | - Juliet Mwanga-Amumpaire
- Mbarara University of Science and Technology, P.O. Box 1410, Mbarara, Uganda.,Epicentre Mbarara Research Centre, P.O. Box 1956, Mbarara, Uganda
| | - Yap Boum
- Mbarara University of Science and Technology, P.O. Box 1410, Mbarara, Uganda.,Epicentre Mbarara Research Centre, P.O. Box 1956, Mbarara, Uganda
| |
Collapse
|
43
|
Beshir KB, Sepúlveda N, Bharmal J, Robinson A, Mwanguzi J, Busula AO, de Boer JG, Sutherland C, Cunningham J, Hopkins H. Plasmodium falciparum parasites with histidine-rich protein 2 (pfhrp2) and pfhrp3 gene deletions in two endemic regions of Kenya. Sci Rep 2017; 7:14718. [PMID: 29116127 PMCID: PMC5677122 DOI: 10.1038/s41598-017-15031-2] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 10/19/2017] [Indexed: 01/12/2023] Open
Abstract
Deletions of the Plasmodium falciparum hrp2 and hrp3 genes can affect the performance of HRP2-based malaria rapid diagnostic tests (RDTs). Such deletions have been reported from South America, India and Eritrea. Whether these parasites are widespread in East Africa is unknown. A total of 274 samples from asymptomatic children in Mbita, western Kenya, and 61 genomic data from Kilifi, eastern Kenya, were available for analysis. PCR-confirmed samples were investigated for the presence of pfhrp2 and pfhrp3 genes. In samples with evidence of deletion, parasite presence was confirmed by amplifying three independent genes. We failed to amplify pfhrp2 from 25 of 131 (19.1%) PCR-confirmed samples. Of these, only 8 (10%) samples were microscopic positive and were classified as pfhrp2-deleted. Eight microscopically-confirmed pfhrp2-deleted samples with intact pfhrp3 locus were positive by HRP2-based RDT. In addition, one PCR-confirmed infection showed a deletion at the pfhrp3 locus. One genomic sample lacked pfhrp2 and one lacked pfhrp3. No sample harbored parasites lacking both genes. Parasites lacking pfhrp2 are present in Kenya, but may be detectable by HRP-based RDT at higher parasitaemia, possibly due to the presence of intact pfhrp3. These findings warrant further systematic study to establish prevalence and diagnostic significance.
Collapse
Affiliation(s)
| | - Nuno Sepúlveda
- London School of Hygiene and Tropical Medicine, London, UK
- Centre for Statistics and Applications of University of Lisbon, Lisbon, Portugal
| | - Jameel Bharmal
- London School of Hygiene and Tropical Medicine, London, UK
| | - Ailie Robinson
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Annette Obukosia Busula
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
- Kaimosi Friends University College, Kaimosi, Kenya
| | - Jetske Gudrun de Boer
- Laboratory of Entomology, Wageningen University, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
- Netherlands Institute of Ecology, Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
| | | | - Jane Cunningham
- Global Malaria Programme, World Health Organization (WHO-GMP), Geneva, Switzerland
| | - Heidi Hopkins
- London School of Hygiene and Tropical Medicine, London, UK
| |
Collapse
|
44
|
Diallo MA, Diongue K, Ndiaye M, Gaye A, Deme A, Badiane AS, Ndiaye D. Evaluation of CareStart™ Malaria HRP2/pLDH (Pf/pan) Combo Test in a malaria low transmission region of Senegal. Malar J 2017; 16:328. [PMID: 28797261 PMCID: PMC5553680 DOI: 10.1186/s12936-017-1980-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 08/07/2017] [Indexed: 11/10/2022] Open
Abstract
Background This study was initiated from the observation that prevalence of malaria obtained with rapid diagnostic test (RDT) (CareStart™Malaria HRP2/pLDH Combo Test) was higher than in microscopy in a malaria low transmission area of Senegal. PCR was then performed to evaluate the performance of the RDT compared to microscopy in clinical settings. Methods The study included 215 patients suspected of malaria in two peri-urban area of Dakar. Finger-pick blood samples were tested using RDT (CareStart™Malaria HRP2/pLDH Combo Test). Venous blood samples were collected for light microscopy and PCR (gold standard). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated as performance characteristics. Results Considering PCR as the gold standard, CareStart™RDT showed high sensitivity (97.3%) and specificity (94.1%) with PPV and NPV of 97.3 and 94.1%, respectively, while microscopy had a sensitivity and specificity of 93.2 and 100%, respectively, and PPV and NPV of 100 and 87.2%, respectively. Conclusions Malaria CareStart™RDT test demonstrated a superior sensitivity compared to microscopy, which is the gold standard for malaria diagnosis. CareStart™RDT could be a useful tool in individuals suspected of malaria even in areas where prevalence is low.
Collapse
Affiliation(s)
- Mamadou Alpha Diallo
- Laboratoire de Parasitologie-Mycologie, Université Cheikh Anta Diop de Dakar, Avenue Cheikh Anta Diop, Fann, BP 5005, Dakar, Senegal.
| | - Khadim Diongue
- Laboratoire de Parasitologie-Mycologie, Université Cheikh Anta Diop de Dakar, Avenue Cheikh Anta Diop, Fann, BP 5005, Dakar, Senegal
| | - Mouhamadou Ndiaye
- Laboratoire de Parasitologie-Mycologie, Université Cheikh Anta Diop de Dakar, Avenue Cheikh Anta Diop, Fann, BP 5005, Dakar, Senegal
| | - Amy Gaye
- Laboratoire de Parasitologie-Mycologie, Université Cheikh Anta Diop de Dakar, Avenue Cheikh Anta Diop, Fann, BP 5005, Dakar, Senegal
| | - Awa Deme
- Laboratoire de Parasitologie-Mycologie, Université Cheikh Anta Diop de Dakar, Avenue Cheikh Anta Diop, Fann, BP 5005, Dakar, Senegal
| | - Aida S Badiane
- Laboratoire de Parasitologie-Mycologie, Université Cheikh Anta Diop de Dakar, Avenue Cheikh Anta Diop, Fann, BP 5005, Dakar, Senegal
| | - Daouda Ndiaye
- Laboratoire de Parasitologie-Mycologie, Université Cheikh Anta Diop de Dakar, Avenue Cheikh Anta Diop, Fann, BP 5005, Dakar, Senegal
| |
Collapse
|