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Tréhard H, Musset L, Lazrek Y, White M, Pelleau S, Mueller I, Djossou F, Sanna A, Landier J, Gaudart J, Mosnier E. Which diagnostic test to use for Testing and Treatment strategies in Plasmodium vivax low-transmission settings: a secondary analysis of a longitudinal interventional study. LANCET REGIONAL HEALTH. AMERICAS 2024; 38:100883. [PMID: 39319096 PMCID: PMC11420435 DOI: 10.1016/j.lana.2024.100883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 08/05/2024] [Accepted: 08/19/2024] [Indexed: 09/26/2024]
Abstract
Background The lack of sensitive field tests to diagnose blood stages and hypnozoite carriers prevents Testing and Treatment (TAT) strategies to achieve Plasmodium vivax elimination in low-transmission settings, but recent advances in Polymerase Chain Reaction (PCR) and serology position them as promising tools. This study describes a PCR-based TAT strategy (PCRTAT) implemented in Saint Georges (SGO), French Guiana, and explores alternative strategies (seroTAT and seroPCRTAT) to diagnose and treat P. vivax carriers. Methods The PALUSTOP cohort study implemented in SGO (September 2017 to December 2018) screened participants for P. vivax using PCR tests and treated positive cases. Serology was also performed. Passive detection of P. vivax infection occurred during follow-up. Participants were categorised into overlapping treatment groups based on 2017 PCR and serological results. Strategies were described in terms of participants targeted or missed, primaquine contraindications (pregnancy, G6PD severe or intermediate deficiency), and sociodemographic characteristics. Findings In 2017, 1567 inhabitants were included, aged 0-92 years. A total of 90 (6%) were P. vivax carriers and 390 seropositive (25%). PCRTAT missed 282 seropositive individuals while seroTAT would have missed 21 PCR-positive cases. Primaquine contraindications ranged from 12% to 17% across strategies. Interpretation Serology and PCR are promising tools for targeted treatment strategies in P. vivax low-transmission settings, when field compatible sensitive tests will be available. Both seem necessary to capture blood stages and potential hypnozoite carriers, while avoiding mass treatment. However, high primaquine contraindications rates need consideration for successful elimination. Funding Supported by European Funds for Regional Development, French Guiana Regional Health Agency, Pan American Health Organization, WHO, French Ministry for Research.
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Affiliation(s)
- Hélène Tréhard
- Aix Marseille Univ, INSERM, IRD, SESSTIM, Sciences Economiques & Sociales de la Santé & Traitement de l’Information Médicale, Aix Marseille Institute of Public Health ISSPAM, Marseille, France
| | - Lise Musset
- Laboratoire de parasitologie, World Health Organization Collaborating Center for Surveillance of Antimalarial Drug Resistance, Centre National de Référence du Paludisme, Institut Pasteur de la Guyane, Cayenne, French Guiana
| | - Yassamine Lazrek
- Laboratoire de parasitologie, World Health Organization Collaborating Center for Surveillance of Antimalarial Drug Resistance, Centre National de Référence du Paludisme, Institut Pasteur de la Guyane, Cayenne, French Guiana
| | - Michael White
- Infectious Diseases Epidemiology and Analytics, Department of Global Health, Institut Pasteur, Université Paris Cité, Paris, France
| | - Stéphane Pelleau
- Infectious Diseases Epidemiology and Analytics, Department of Global Health, Institut Pasteur, Université Paris Cité, Paris, France
| | - Ivo Mueller
- Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Felix Djossou
- Unité des Maladies Infectieuses et Tropicales, Centre Hospitalier de Cayenne, French Guiana
| | - Alice Sanna
- Centre d’Investigation Clinique Antilles Guyane CIC, Centre Hospitalier de Cayenne, French Guiana
| | - Jordi Landier
- Aix Marseille Univ, INSERM, IRD, SESSTIM, Sciences Economiques & Sociales de la Santé & Traitement de l’Information Médicale, Aix Marseille Institute of Public Health ISSPAM, Marseille, France
| | - Jean Gaudart
- Aix Marseille Univ, INSERM, IRD, ISSPAM, SESSTIM, UMR1252, AP HM, Hop Timone, BioSTIC, Biostatistic & ICT, Marseille, France
| | - Emilie Mosnier
- Aix Marseille Univ, INSERM, IRD, SESSTIM, Sciences Economiques & Sociales de la Santé & Traitement de l’Information Médicale, Aix Marseille Institute of Public Health ISSPAM, Marseille, France
- Grant Management Office, University of Health Sciences, Phnom Penh, Cambodia
- French Agency for Research on AIDS, Viral Hepatitis and Emerging Infectious diseases (ANRS-MIE), Phnom Penh, Cambodia
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Cáceres Carrera L, Santamaría AM, Castillo AM, Romero L, Urriola E, Torres-Cosme R, Calzada JE. Detection through the use of RT-MqPCR of asymptomatic reservoirs of malaria in samples of patients from the indigenous Comarca of Guna Yala, Panama: Essential method to achieve the elimination of malaria. PLoS One 2024; 19:e0305558. [PMID: 39046959 PMCID: PMC11268588 DOI: 10.1371/journal.pone.0305558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 06/02/2024] [Indexed: 07/27/2024] Open
Abstract
BACKGROUND Plasmodium vivax is the main causative agent of malaria in Panama. However, the prevalence of asymptomatic infections in the different endemic regions remains unknown. Understanding the epidemiological behavior of asymptomatic infections is essential for the elimination of malaria. This study aimed to determine the prevalence of asymptomatic malarial infections in one of the main endemic regions of Panama using multiplex real-time reverse transcription RT-MqPCR. METHODS A cross-sectional study was conducted in three communities in the Guna Yala Comarca. A total of 551 thick blood smears and their respective samples on filter paper were collected from volunteers of different ages and sexes from June 20 to 25, 2016. Infections by the Plasmodium spp. were diagnosed using microscopy and RT-MqPCR. All statistical analyses were performed using the R software. RESULTS The average prevalence of asymptomatic infections by P. vivax in the three communities detected by RT-MqPCR was 9.3%, with Ukupa having the highest prevalence (13.4%), followed by Aidirgandi (11.1%) and Irgandi (3.3%). A total of 74 samples were diagnosed as asymptomatic infections using RT-MqPCR. Light microscopy (LM) detected that 17.6% (13/74) of the asymptomatic samples and 82.4% (61/74) were diagnosed as false negatives. A 100% correlation was observed between samples diagnosed using LM and RT-MqPCR. A total of 52.7% (39/74) of the asymptomatic patients were female and 85.1% (63/74) were registered between the ages of 1 and 21 years. Factors associated with asymptomatic infection were community (aOR = 0.38 (95% CI 0.17-0.83), p < 0.001) and age aOR = 0.98 (95% CI 0.97-1.00), p < 0.05); F = 5.38; p < 0.05). CONCLUSIONS This study provides novel evidence of the considerable prevalence of asymptomatic P. vivax infections in the endemic region of Kuna Yala, representing a new challenge that requires immediate attention from the National Malaria Program. The results of this study provide essential information for the health authorities responsible for developing new policies. Furthermore, it will allow program administrators to reorient and design effective malaria control strategies that consider asymptomatic infections as a fundamental part of malaria control and move towards fulfilling their commitment to eliminate it.
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Affiliation(s)
- Lorenzo Cáceres Carrera
- Departmento de Entomología Médica del Instituto Conmemorativo Gorgas de Estudios de la Salud, Ciudad de Panamá, Panamá
| | - Ana María Santamaría
- Departmento de Parasitología del Instituto Conmemorativo Gorgas de Estudios de la Salud, Ciudad de Panamá, Panamá
| | - Anakena Margarita Castillo
- Departmento de Entomología Médica del Instituto Conmemorativo Gorgas de Estudios de la Salud, Ciudad de Panamá, Panamá
| | - Luis Romero
- Laboratorio Central de Referencia en Salud Pública del Instituto Conmemorativo Gorgas de Estudios de la Salud, Ciudad de Panamá, Panamá
| | - Eduardo Urriola
- Facultad de Ciencias Biomédicas, Universidad Latina de Panamá, Ciudad de Panamá, Panamá
| | - Rolando Torres-Cosme
- Departmento de Entomología Médica del Instituto Conmemorativo Gorgas de Estudios de la Salud, Ciudad de Panamá, Panamá
| | - José Eduardo Calzada
- Departmento de Parasitología del Instituto Conmemorativo Gorgas de Estudios de la Salud, Ciudad de Panamá, Panamá
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Pinedo-Cancino V, Arista KM, Baldeviano GC, Saavedra-Langer R, Arana A, Vásquez-Chasnamote ME, Valle-Campos A, Castro JC, Ventocilla JA, Smith ES, Lescano AG, Ruíz-Mesia L. Unravelling heterogeneous malaria transmission dynamics in the Peruvian Amazon: insights from a cross-sectional survey. Malar J 2024; 23:209. [PMID: 39010126 PMCID: PMC11251108 DOI: 10.1186/s12936-024-05032-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Accepted: 06/29/2024] [Indexed: 07/17/2024] Open
Abstract
BACKGROUND Malaria remains a global health challenge, particularly in Peru's Loreto region. Despite ongoing efforts, high infection rates and asymptomatic cases perpetuate transmission. The Peruvian Ministry of Health's "Zero Malaria Plan" targets elimination. This novel study combines microscopic, molecular, and serological techniques to assess transmission intensity, identify epidemiological risk factors, and characterize species-specific patterns across villages. The findings aim to inform targeted interventions and support broader malaria elimination efforts in line with the Zero Malaria Plan initiative. METHODS A cross-sectional malaria survey was conducted in the Zungarococha community, comprising the villages Llanchama (LL), Ninarumi (NI), Puerto Almendra (PA), and Zungarococha (ZG), using microscopic, molecular, and serological techniques to evaluate malaria transmission intensity. Statistical analysis, including multivariate-adjusted analysis, seroprevalence curves, and spatial clustering analysis, were performed to assess malaria prevalence, exposure, and risk factors. RESULTS The survey revealed a high prevalence of asymptomatic infections (6% by microscopy and 18% by PCR), indicating that molecular methods are more sensitive for detecting asymptomatic infections. Seroprevalence varied significantly between villages, reflecting the heterogeneous malaria transmission dynamics. Multivariate analysis identified age, village, and limited bed net use as significant risk factors for malaria infection and species-specific exposure. Seroprevalence curves demonstrated community-specific patterns, with Llanchama and Puerto Almendra showing the highest seroconversion rates for both Plasmodium species. CONCLUSIONS The study highlights the diverse nature of malaria transmission in the Loreto region, particularly nothing the pronounced heterogeneity as transmission rates decline, especially in residual malaria scenarios. The use of molecular and serological techniques enhances the detection of current infections and past exposure, aiding in the identification of epidemiological risk factors. These findings underscore the importance of using molecular and serological tools to characterize malaria transmission patterns in low-endemic areas, which is crucial for planning and implementing targeted interventions and elimination strategies. This is particularly relevant for initiatives like the Zero Malaria Plan in the Peruvian Amazon.
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Affiliation(s)
- Viviana Pinedo-Cancino
- Laboratorio de Investigación de Productos Naturales Antiparasitarios de la Amazonía (LIPNAA), Centro de Investigaciones de Recursos Naturales de la UNAP (CIRNA), Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru.
- Facultad de Medicina Humana, Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru.
- School of Medicine, Universidad Continental, Huancayo, Peru.
- Facultad de Medicina Humana, Universidad Peruana Cayetano Heredia (UPCH), Lima, Peru.
| | - Katty M Arista
- Laboratorio de Investigación de Productos Naturales Antiparasitarios de la Amazonía (LIPNAA), Centro de Investigaciones de Recursos Naturales de la UNAP (CIRNA), Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru
| | - G Christian Baldeviano
- U.S. Naval Medical Research Unit SOUTH (NAMRU SOUTH), Bellavista, Callao, Peru
- Bluebird Bio, Inc., Somerville, MA, USA
| | - Rafael Saavedra-Langer
- Laboratorio de Investigación de Productos Naturales Antiparasitarios de la Amazonía (LIPNAA), Centro de Investigaciones de Recursos Naturales de la UNAP (CIRNA), Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru
- Departamento de Bioquímica E Inmunología, Instituto de Ciencias Biológicas, Universidad Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Andrei Arana
- Laboratorio de Investigación de Productos Naturales Antiparasitarios de la Amazonía (LIPNAA), Centro de Investigaciones de Recursos Naturales de la UNAP (CIRNA), Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru
| | - Maria E Vásquez-Chasnamote
- Laboratorio de Investigación de Productos Naturales Antiparasitarios de la Amazonía (LIPNAA), Centro de Investigaciones de Recursos Naturales de la UNAP (CIRNA), Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru
| | - Andree Valle-Campos
- Departamento de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos (UNMSM), Lima, Peru
| | - Juan C Castro
- Unidad Especializada del Laboratorio de Investigación en Biotecnología, Centro de Investigaciones de Recursos Naturales de la UNAP (CIRNA), Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru
- Departamento Académico de Ciencias Biomédicas y Biotecnología, Facultad de Ciencias Biológicas, Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru
| | | | - Edward S Smith
- Facultad de Medicina Humana, Universidad Peruana Cayetano Heredia (UPCH), Lima, Peru
| | - Andres G Lescano
- U.S. Naval Medical Research Unit SOUTH (NAMRU SOUTH), Bellavista, Callao, Peru
- Clima, Latin American Center of Excellence for Climate Change and Health, and Emerge, Emerging Diseases and Climate Change Research Unit, School of Public Health and Administration, Universidad Peruana Cayetano Heredia (UPCH), Lima, Peru
| | - Lastenia Ruíz-Mesia
- Laboratorio de Investigación de Productos Naturales Antiparasitarios de la Amazonía (LIPNAA), Centro de Investigaciones de Recursos Naturales de la UNAP (CIRNA), Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru
- Facultad de Ingeniería Química, Universidad Nacional de la Amazonía Peruana (UNAP), Iquitos, Peru
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Oyegoke OO, Akoniyon OP, Maharaj L, Adewumi TS, Malgwi SA, Aderoju SA, Fatoba AJ, Adeleke MA, Maharaj R, Okpeku M. Molecular detection of sub-microscopic infections and Plasmodium falciparum histidine-rich protein-2 and 3 gene deletions in pre-elimination settings of South Africa. Sci Rep 2024; 14:16024. [PMID: 38992085 PMCID: PMC11239831 DOI: 10.1038/s41598-024-60007-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 04/17/2024] [Indexed: 07/13/2024] Open
Abstract
South Africa's efforts toward eliminating malaria have positioned the country in the pre-elimination stage. Imported and sub-microscopic cases still contribute to the persistence of malaria in regions of low transmission as identified in this study where diagnostics is built largely on the use of Rapid Diagnostic Test (RDT). However, the presence of Pfhrp2/3 gene deletion is known to interfere with the accuracy of diagnosis with the use of RDT. Malaria elimination and detection of Pfhrp2/3 gene deletion in the pre-elimination setting requires accurate molecular surveillance. With the core objective of this study being the determination of the presence sub-microscopic malaria cases and deleted Pfhrp2/3 gene markers, a total of 354 samples were collected from five districts of KwaZulu Natal, South Africa. These samples were prepared for molecular analysis using primers and PCR conditions specific for amplification of 18S rRNA and msp-1gene. Positive amplicons were analysed for the presence of Pfhrp2/3 and flanking genes, along with Sanger sequencing and phylogenetic studies. Out of 354 samples collected 339 were tested negative with PfHRP2 based RDTs. Of these Pfhrp2 and Pfhrp3 gene deletions were confirmed in 94.7% (18/19) and 100% (19/19) respectively. High migration rate (75%) among the study participants was noted and phylogenetic analysis of sequenced isolates showed close evolutionary relatedness with India, United Kingdom, Iran, and Myanmar and China isolates. Molecular-based test is recommended as an essential surveillance tool for malaria management programs as the target focuses on elimination.
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Affiliation(s)
- Olukunle O Oyegoke
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Olusegun P Akoniyon
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Leah Maharaj
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Taiye S Adewumi
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66046, USA
| | - Samson A Malgwi
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Samuel A Aderoju
- Department of Mathematics and Statistics, Kwara State University, Ilorin, Nigeria
| | - Abiodun J Fatoba
- Department of Genetics, Genomics and Bioinformatics, University of Tennessee Health Science Centre, Memphis, TN, 38016, USA
| | - Matthew A Adeleke
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Rajendra Maharaj
- Malaria Research Unit, South African Medical Research Council, Durban, South Africa
| | - Moses Okpeku
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa.
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Marzano-Miranda A, Pereira Cardoso-Oliveira G, Carla de Oliveira I, Carvalho Mourão L, Reis Cussat L, Gomes Fraga V, Delfin Chávez Olórtegui C, Jesus Fernandes Fontes C, Castanheira Bartholomeu D, Braga EM. Identification and serological responses to a novel Plasmodium vivax merozoite surface protein 1 ( PvMSP-1) derived synthetic peptide: a putative biomarker for malaria exposure. PeerJ 2024; 12:e17632. [PMID: 38948214 PMCID: PMC11212635 DOI: 10.7717/peerj.17632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 06/04/2024] [Indexed: 07/02/2024] Open
Abstract
Background The integration of diagnostic methods holds promise for advancing the surveillance of malaria transmission in both endemic and non-endemic regions. Serological assays emerge as valuable tools to identify and delimit malaria transmission, serving as a complementary method to rapid diagnostic tests (RDT) and thick smear microscopy. Here, we evaluate the potential of antibodies directed against peptides encompassing the entire amino acid sequence of the PvMSP-1 Sal-I strain as viable serological biomarkers for P. vivax exposure. Methods We screened peptides encompassing the complete amino acid sequence of the Plasmodium vivax Merozoite Surface Protein 1 (PvMSP-1) Sal-I strain as potential biomarkers for P. vivax exposure. Here, immunodominant peptides specifically recognized by antibodies from individuals infected with P. vivax were identified using the SPOT-synthesis technique followed by immunoblotting. Two 15-mer peptides were selected based on their higher and specific reactivity in immunoblotting assays. Subsequently, peptides p70 and p314 were synthesized in soluble form using SPPS (Solid Phase Peptide Synthesis) and tested by ELISA (IgG, and subclasses). Results This study unveils the presence of IgG antibodies against the peptide p314 in most P. vivax-infected individuals from the Brazilian Amazon region. In silico B-cell epitope prediction further supports the utilization of p314 as a potential biomarker for evaluating malaria transmission, strengthened by its amino acid sequence being part of a conserved block of PvMSP-1. Indeed, compared to patients infected with P. falciparum and uninfected individuals never exposed to malaria, P. vivax-infected patients have a notably higher recognition of p314 by IgG1 and IgG3.
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Affiliation(s)
- Aline Marzano-Miranda
- Department of Parasitology, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | | | - Luiza Carvalho Mourão
- Department of Parasitology, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Letícia Reis Cussat
- Department of Parasitology, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Vanessa Gomes Fraga
- Department of Parasitology, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | | | | | - Erika M. Braga
- Department of Parasitology, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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Prasetyorini N, Erwan NE, Sardjono TW, Nurseta T, Utomo RP, Nugraha RYB, Cahayani WA, Rukmigarsari E, Arinugraha LN, Fitri LE. HIF-1α regulated pathomechanism of low birth weight through angiogenesis factors in placental Plasmodium vivax infection. F1000Res 2024; 11:131. [PMID: 38884107 PMCID: PMC11179053 DOI: 10.12688/f1000research.73820.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/03/2024] [Indexed: 06/18/2024] Open
Abstract
Background Malaria in pregnancy leads to placental malaria. The primary pathogenesis of the complex fetal implications in placental malaria is tissue hypoxia due to sequestrations of Plasmodium falciparum-infected erythrocytes in the placenta. However, the pathomechanism of placental Plasmodium vivax infection has not been thoroughly investigated. Hypoxia-inducible factor-1α (HIF-1α) is a key transcriptional mediator of the response to hypoxic conditions, which interacts with the change and imbalances of many chemical mediators, including angiogenic factors, leading to fetal growth abnormality. Methods This study was conducted cross-sectionally in Maumere, Sikka Regency, East Nusa Tenggara Province, previously known as one of the malaria endemic areas with a high incidence of low birth weight (LBW) cases. This study collected peripheral and umbilical blood samples and placental tissues from mothers who delivered their babies with LBW at the TC Hiller Regional Hospital. All of the blood samples were examined for parasites by microscopic and PCR techniques, while the plasma levels of VEGF, PlGF, VEGFR-1, VEGFR-2, and HIF-1α were determined using ELISA. The sequestration of infected erythrocytes and hemozoin was determined from placental histological slides, and the expression of placenta angiogenic factors was observed using the immunofluorescent technique. Results In this study, 33 cases had complete data to be analyzed. Of them, 19 samples were diagnosed as vivax malaria and none of falciparum malaria. There were significant differences in Δ 10th percentile growth curve of baby's body weights and also all angiogenic factors in placental tissues {VEGF, PlGF, and VEGFR-1, VEGFR-2, and HIF-1α} between those infected and not infected cases (p<0.05), but not for VEGF and VEGFR-2 in the plasma. Conclusion This study indicated that Plasmodium vivax sequestration may promote LBW through alterations and imbalances in angiogenic factors led by HIF-1α.
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Affiliation(s)
- Nugrahanti Prasetyorini
- Doctoral Program in Medical Science, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
- Malaria Research Group, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
- Department of Obstetrics & Gynecology, Faculty of Medicine Universitas Brawijaya/dr Saiful Anwar Hospital, Malang, Indonesia
| | - Nabila Erina Erwan
- Malaria Research Group, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
- Master Program in Biomedical Science, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Teguh Wahju Sardjono
- Malaria Research Group, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
- Department of Parasitology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Tatit Nurseta
- Department of Obstetrics & Gynecology, Faculty of Medicine Universitas Brawijaya/dr Saiful Anwar Hospital, Malang, Indonesia
| | - Rudi Priyo Utomo
- Department of Obstetrics & Gynecology, dr T.C. Hillers Regional Hospital, Maumere, Sikka Regency, NTT, Indonesia
| | - Rivo Yudhinata Brian Nugraha
- Malaria Research Group, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
- Department of Parasitology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Wike Astrid Cahayani
- Malaria Research Group, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
- Department of Anatomy and Histology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Ettie Rukmigarsari
- Mathematics Education Study Program, Faculty of Teacher Training and Education, University of Islam Malang, Malang, Indonesia
| | | | - Loeki Enggar Fitri
- Malaria Research Group, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
- Department of Parasitology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
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Tilahun A, Yimer M, Gelaye W, Tegegne B, Endalamaw D, Estifanos F, Abebaw A, Abere A. Comparison of malaria diagnostic methods for detection of asymptomatic Plasmodium infections among pregnant women in northwest Ethiopia. BMC Infect Dis 2024; 24:492. [PMID: 38745114 PMCID: PMC11092159 DOI: 10.1186/s12879-024-09369-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: 11/04/2023] [Accepted: 04/30/2024] [Indexed: 05/16/2024] Open
Abstract
BACKGROUND Malaria in pregnancy remains a major public health problem in the globe, especially in sub-Saharan Africa. In malaria endemic areas, most pregnant women remain asymptomatic, but malaria could still cause complications on the mother and her offspring; as well as serve as reservoirs to transmit infection. Despite these effects, no attention is given to the diagnosis of asymptomatic Plasmodium infections (APIs) using highly sensitive and specific laboratory diagnostic tools in Ethiopia. Therefore, the goal of this study was to compare the performance of Rapid Diagnostic Test (RDT), microscopy and real-time polymerase chain reaction (RT-PCR) to detect APIs among pregnant women. METHODS A health facility based cross -sectional study was conducted among pregnant women attending antenatal care at Fendeka town health facilities Jawi district, northwest Ethiopia from February to March, 2019. A total of 166 participants were enrolled by using convenient sampling technique. Socio-demographic features were collected using a semi structured questionnaire. Dried blood spot (DBS) samples were collected for molecular analysis. Asymptomatic Plasmodium infection on pregnant women was diagnosed using RDT, microscopy and RT-PCR. Descriptive statistics were used to determine the prevalence of APIs. Method comparison was performed, and Cohen's kappa coefficient (k) was used to determine the degree of agreement among the diagnostic methods. Parasite densities were also calculated. RESULTS The prevalence of API was 9.6%, 11.4% and 18.7% using RDT, microscopy and RT-PCR, respectively. The overall proportion of API was 19.3%. Sensitivity of the RDT was 83.3% as compared with microscopy. Rapid Diagnostic Test and microscopy also showed sensitivity of 50% and 60%, respectively, as compared with RT-PCR. The mean parasite density was 3213 parasites/µl for P falciparum and 1140 parasites/µl of blood for P. vivax. CONCLUSION Prevalence of API in the study area was high. Both RDT and microscopy had lower sensitivity when compared with RT-PCR. Therefore, routine laboratory diagnosis of API among pregnant women should be given attention and done with better sensitive and specific laboratory diagnostic tools.
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Affiliation(s)
- Adane Tilahun
- Department of Medical Laboratory Science, College of Medicine and Health sciences, Debre Markos University, Debre Markos, Ethiopia.
| | - Mulat Yimer
- Department of Medical Laboratory Sciences, School of Health Sciences, College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia
| | - Woynshet Gelaye
- Department of Medical Laboratory Sciences, School of Health Sciences, College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia
| | | | | | | | - Abtie Abebaw
- Department of Medical Laboratory Science, College of Medicine and Health sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Aberham Abere
- School of Biomedical and Laboratory Sciences, College of Medicine and Health sciences, University of Gondar, Gondar, Ethiopia
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Pickering PA, Harris I, Smith D, McCallum F, Kaminiel P, Auliff A, Cheng Q. Burden of Submicroscopic Plasmodium Infections and Detection of kelch13 Mutant Parasites in Military and Civilian Populations in Papua New Guinea. Am J Trop Med Hyg 2024; 110:639-647. [PMID: 38377613 PMCID: PMC10993850 DOI: 10.4269/ajtmh.23-0508] [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: 08/01/2023] [Accepted: 11/22/2023] [Indexed: 02/22/2024] Open
Abstract
Malaria remains a major public health problem in Papua New Guinea (PNG) and an important force health protection issue for both PNG and Australian Defence Forces. To investigate the malaria burden in the military and civilians residing on military bases, a cross-sectional survey was conducted in April 2019 at three military bases in Wewak, Manus Island, and Vanimo, PNG. A total of 1,041 participants were enrolled; 235 military personnel from three bases and 806 civilians from Wewak and Vanimo. Polymerase chain reaction (PCR) revealed an overall high prevalence of Plasmodium infection in both the military and civilians. Among the military, the infection prevalence was significantly higher in Wewak (35.5%) and Vanimo (33.3%) bases than on Manus Island (11.8%). Among civilians, children (<16 years old) had significantly higher odds of being PCR positive than adults (≥16 years old). At Wewak and Vanimo, Plasmodium vivax accounted for 85.4%, 78.2%, and 66.2% of infections in military, children, and adult populations. Overall, 87.3%, 41.3%, and 61.3% of Plasmodium infections in the military, children, and adults, respectively, were detected only by PCR, not by microscopy (submicroscopic [SM] infections). Children had a significantly lower proportion of SM infections than adults and Papua New Guinea Defence Force personnel. Infection status was not associated with hemoglobin levels in these populations at the time of the survey. Mutant kelch13 (C580Y) parasites were identified in 5/68 Plasmodium falciparum-infected individuals. The survey results indicate extensive malaria transmission on these bases, especially in Wewak and Vanimo. More intensified interventions are required to reduce malaria transmission on PNG military bases.
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Affiliation(s)
- Paul A. Pickering
- Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
| | - Ivor Harris
- Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
| | - David Smith
- Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
| | - Fiona McCallum
- Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
| | - Peter Kaminiel
- Papua New Guinea Defence Force Health Service, Port Moresby, Papua New Guinea
| | - Alyson Auliff
- Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
| | - Qin Cheng
- Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
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Dembélé P, Cissoko M, Diarra AZ, Doumbia L, Koné A, Magassa MH, Mehadji M, Thera MA, Ranque S. Evaluation of the Performance of Rapid Diagnostic Tests for Malaria Diagnosis and Mapping of Different Plasmodium Species in Mali. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2024; 21:228. [PMID: 38397717 PMCID: PMC10888130 DOI: 10.3390/ijerph21020228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 02/09/2024] [Accepted: 02/11/2024] [Indexed: 02/25/2024]
Abstract
BACKGROUND The first-line diagnosis of malaria in Mali is based on the use of rapid diagnostic tests (RDT) that detect the Histidin Rich Protein 2 (HRP2) antigen specific to Plasmodium falciparum. Our study, based on a real-time polymerase chain reaction (qPCR) gold standard, aimed to describe the distribution of the Plasmodium species in each administrative region of Mali and to assess the performance of RDTs. METHODS We randomly selected 150 malaria-negative and up to 30 malaria-positive RDTs in 41 sites distributed in 9 regions of Mali. DNA extracted from the RDT nitrocellulose strip was assayed with a pan-Plasmodium qPCR. Positive samples were then analyzed with P. falciparum-, P. malariae-, P. vivax-, or P. ovale-specific qPCRs. RESULTS Of the 1496 RDTs, 258 (18.6%) were positive for Plasmodium spp., of which 96.9% were P. falciparum. The P. vivax prevalence reached 21.1% in the north. RDT displayed acceptable diagnostic indices; the lower CI95% bounds of Youden indices were all ≥0.50, except in the north (Youden index 0.66 (95% CI [0.44-0.82]) and 0.63 (95% CI [0.33-0.83]. CONCLUSIONS Overall, RDT diagnostic indices are adequate for the biological diagnosis of malaria in Mali. We recommend the use of RDTs detecting P. vivax-specific antigens in the north.
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Affiliation(s)
- Pascal Dembélé
- Institut Hospitalo-Universitaire Méditerranée Infection (IHU), Aix Marseille Université, 13005 Marseille, France; (P.D.); (A.Z.D.); (L.D.); (M.M.)
- Aix-Marseille University, IRD, AP-HM, SSA, VITROME, 13005 Marseille, France
- Programme National de Lutte Contre le Paludisme (PNLP), Bamako BP 233, Mali; (M.C.); (M.H.M.)
| | - Mady Cissoko
- Programme National de Lutte Contre le Paludisme (PNLP), Bamako BP 233, Mali; (M.C.); (M.H.M.)
- Malaria Research and Training Center (MRTC), FMOS-FAPH, Mali-NIAID-ICER, Université des Sciences, des Techniques et des Technologies de Bamako, Bamako BP 1805, Mali;
| | - Adama Zan Diarra
- Institut Hospitalo-Universitaire Méditerranée Infection (IHU), Aix Marseille Université, 13005 Marseille, France; (P.D.); (A.Z.D.); (L.D.); (M.M.)
- Aix-Marseille University, IRD, AP-HM, SSA, VITROME, 13005 Marseille, France
| | - Lassana Doumbia
- Institut Hospitalo-Universitaire Méditerranée Infection (IHU), Aix Marseille Université, 13005 Marseille, France; (P.D.); (A.Z.D.); (L.D.); (M.M.)
- Laboratoire de Biologie Moléculaire Appliquée (LBMA), Université des Sciences, des Techniques et des Technologies de Bamako, Badalabougou, Bamako BP 423, Mali;
| | - Aïssata Koné
- Laboratoire de Biologie Moléculaire Appliquée (LBMA), Université des Sciences, des Techniques et des Technologies de Bamako, Badalabougou, Bamako BP 423, Mali;
| | - Mahamadou H. Magassa
- Programme National de Lutte Contre le Paludisme (PNLP), Bamako BP 233, Mali; (M.C.); (M.H.M.)
| | - Maissane Mehadji
- Institut Hospitalo-Universitaire Méditerranée Infection (IHU), Aix Marseille Université, 13005 Marseille, France; (P.D.); (A.Z.D.); (L.D.); (M.M.)
- Aix-Marseille University, IRD, AP-HM, SSA, VITROME, 13005 Marseille, France
| | - Mahamadou A. Thera
- Malaria Research and Training Center (MRTC), FMOS-FAPH, Mali-NIAID-ICER, Université des Sciences, des Techniques et des Technologies de Bamako, Bamako BP 1805, Mali;
| | - Stéphane Ranque
- Institut Hospitalo-Universitaire Méditerranée Infection (IHU), Aix Marseille Université, 13005 Marseille, France; (P.D.); (A.Z.D.); (L.D.); (M.M.)
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10
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Kumar A, Singh PP, Tyagi S, Hari Kishan Raju K, Sahu SS, Rahi M. Vivax malaria: a possible stumbling block for malaria elimination in India. Front Public Health 2024; 11:1228217. [PMID: 38259757 PMCID: PMC10801037 DOI: 10.3389/fpubh.2023.1228217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 12/20/2023] [Indexed: 01/24/2024] Open
Abstract
Plasmodium vivax is geographically the most widely dispersed human malaria parasite species. It has shown resilience and a great deal of adaptability. Genomic studies suggest that P. vivax originated from Asia or Africa and moved to the rest of the world. Although P. vivax is evolutionarily an older species than Plasmodium falciparum, its biology, transmission, pathology, and control still require better elucidation. P. vivax poses problems for malaria elimination because of the ability of a single primary infection to produce multiple relapses over months and years. P. vivax malaria elimination program needs early diagnosis, and prompt and complete radical treatment, which is challenging, to simultaneously exterminate the circulating parasites and dormant hypnozoites lodged in the hepatocytes of the host liver. As prompt surveillance and effective treatments are rolled out, preventing primaquine toxicity in the patients having glucose-6-phosphate dehydrogenase (G6PD) deficiency should be a priority for the vivax elimination program. This review sheds light on the burden of P. vivax, changing epidemiological patterns, the hurdles in elimination efforts, and the essential tools needed not just in India but globally. These tools encompass innovative treatments for eliminating dormant parasites, coping with evolving drug resistance, and the development of potential vaccines against the parasite.
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Affiliation(s)
- Ashwani Kumar
- ICMR - Vector Control Research Centre, Puducherry, India
| | | | - Suchi Tyagi
- ICMR - Vector Control Research Centre, Puducherry, India
| | | | | | - Manju Rahi
- ICMR - Vector Control Research Centre, Puducherry, India
- Indian Council of Medical Research, Hqrs New Delhi, India
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11
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Furtado R, Paul M, Zhang J, Sung J, Karell P, Kim RS, Caillat-Zucman S, Liang L, Felgner P, Bauleni A, Gama S, Buchwald A, Taylor T, Seydel K, Laufer M, Delahaye F, Daily JP, Lauvau G. Cytolytic circumsporozoite-specific memory CD4 + T cell clones are expanded during Plasmodium falciparum infection. Nat Commun 2023; 14:7726. [PMID: 38001069 PMCID: PMC10673885 DOI: 10.1038/s41467-023-43376-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 11/08/2023] [Indexed: 11/26/2023] Open
Abstract
Clinical immunity against Plasmodium falciparum infection develops in residents of malaria endemic regions, manifesting in reduced clinical symptoms during infection and in protection against severe disease but the mechanisms are not fully understood. Here, we compare the cellular and humoral immune response of clinically immune (0-1 episode over 18 months) and susceptible (at least 3 episodes) during a mild episode of Pf malaria infection in a malaria endemic region of Malawi, by analysing peripheral blood samples using high dimensional mass cytometry (CyTOF), spectral flow cytometry and single-cell transcriptomic analyses. In the clinically immune, we find increased proportions of circulating follicular helper T cells and classical monocytes, while the humoral immune response shows characteristic age-related differences in the protected. Presence of memory CD4+ T cell clones with a strong cytolytic ZEB2+ T helper 1 effector signature, sharing identical T cell receptor clonotypes and recognizing the Pf-derived circumsporozoite protein (CSP) antigen are found in the blood of the Pf-infected participants gaining protection. Moreover, in clinically protected participants, ZEB2+ memory CD4+ T cells express lower level of inhibitory and chemotactic receptors. We thus propose that clonally expanded ZEB2+ CSP-specific cytolytic memory CD4+ Th1 cells may contribute to clinical immunity against the sporozoite and liver-stage Pf malaria.
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Affiliation(s)
- Raquel Furtado
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
- RF: BioNTech US, 40 Erie Street, Cambridge, MA, 02139, USA
| | - Mahinder Paul
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
| | - Jinghang Zhang
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
| | - Joowhan Sung
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
- Division of Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Paul Karell
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
| | - Ryung S Kim
- Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
| | - Sophie Caillat-Zucman
- Université de Paris, AP-HP, Hôpital Saint-Louis, Laboratoire d'Immunologie et Histocompatiblité, INSERM UMR976, 75010, Paris, France
| | - Li Liang
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Philip Felgner
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Andy Bauleni
- Malaria Alert Centre, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Syze Gama
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Andrea Buchwald
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Terrie Taylor
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Blantyre, Malawi
- Department of Osteopathic Medical Specialties, Michigan State University, East Lansing, MI, 48824, USA
| | - Karl Seydel
- Blantyre Malaria Project, Kamuzu University of Health Sciences, Blantyre, Malawi
- Department of Osteopathic Medical Specialties, Michigan State University, East Lansing, MI, 48824, USA
| | - Miriam Laufer
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Fabien Delahaye
- Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
- FD: Precision Oncology, Sanofi, Vitry sur Seine, France
| | - Johanna P Daily
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, 10461, USA.
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, 10461, USA.
| | - Grégoire Lauvau
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, 10461, USA.
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12
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Agudelo Higuita NI, Franco-Paredes C, Henao-Martínez AF, Mendez Rojas B, Suarez JA, Naranjo L, Alger J. Migrants in transit across Central America and the potential spread of chloroquine resistant malaria-a call for action. LANCET REGIONAL HEALTH. AMERICAS 2023; 22:100505. [PMID: 37214770 PMCID: PMC10193226 DOI: 10.1016/j.lana.2023.100505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/03/2023] [Accepted: 04/24/2023] [Indexed: 05/24/2023]
Abstract
Human migration has shaped the distribution and patterns of infectious diseases transmission throughout history. Migration is one of the contributing factors that has played an important role in the dissemination of drug-resistant Plasmodium falciparum. Central America and Mexico are important transit points of an increasing migrant flow originating from countries where chloroquine-resistant P. falciparum and vivax are prevalent. Surveillance systems, as well as detection and diagnostic capacities in the Central American region, are limited. The additional challenges imposed by the increasingly mobile population in the region are creating the perfect scenario for the emergence or re-emergence of infectious diseases, such as the introduction of chloroquine-resistant malaria. The development and implementation of transborder, collaborative, and ethical migrant health initiatives in the region are urgently needed. The health of migrant people in transit during their migratory route is of our collective interest and responsibility; their exclusion from health programs based on their legal status contradicts international human rights treaties and is inconsistent with ethical global public health practice.
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Affiliation(s)
- Nelson Iván Agudelo Higuita
- Department of Medicine, Section of Infectious Diseases, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Instituto de Enfermedades Infecciosas y Parasitología Antonio Vidal, Tegucigalpa, Honduras
| | - Carlos Franco-Paredes
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
- Hospital Infantil de México, Federico Gómez, México City, Mexico
| | - Andrés F. Henao-Martínez
- Department of Medicine, Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | | | - José Antonio Suarez
- Facultad de Ciencias Médicas de la Salud. Universidad Internacional SEK. Quito, Ecuador
- Investigador II SNI Senacyt, Panamá City, Panama
| | - Laura Naranjo
- GlaxoSmithKline CARICAM Vaccines, Panama
- Investigador I SNI Senacyt, Panamá City, Panama
| | - Jackeline Alger
- Instituto de Enfermedades Infecciosas y Parasitología Antonio Vidal, Tegucigalpa, Honduras
- Departamento de Laboratorio Clínico, Hospital Escuela, Tegucigalpa, Honduras
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13
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Mazhari R, Takashima E, Longley RJ, Ruybal-Pesantez S, White MT, Kanoi BN, Nagaoka H, Kiniboro B, Siba P, Tsuboi T, Mueller I. Identification of novel Plasmodium vivax proteins associated with protection against clinical malaria. Front Cell Infect Microbiol 2023; 13:1076150. [PMID: 36761894 PMCID: PMC9905245 DOI: 10.3389/fcimb.2023.1076150] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 01/09/2023] [Indexed: 01/26/2023] Open
Abstract
As progress towards malaria elimination continues, the challenge posed by the parasite species Plasmodium vivax has become more evident. In many regions co-endemic for P. vivax and Plasmodium falciparum, as transmission has declined the proportion of cases due to P. vivax has increased. Novel tools that directly target P. vivax are thus warranted for accelerated elimination. There is currently no advanced vaccine for P. vivax and only a limited number of potential candidates in the pipeline. In this study we aimed to identify promising P. vivax proteins that could be used as part of a subunit vaccination approach. We screened 342 P. vivax protein constructs for their ability to induce IgG antibody responses associated with protection from clinical disease in a cohort of children from Papua New Guinea. This approach has previously been used to successfully identify novel candidates. We were able to confirm previous results from our laboratory identifying the proteins reticulocyte binding protein 2b and StAR-related lipid transfer protein, as well as at least four novel candidates with similar levels of predicted protective efficacy. Assessment of these P. vivax proteins in further studies to confirm their potential and identify functional mechanisms of protection against clinical disease are warranted.
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Affiliation(s)
- Ramin Mazhari
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Rhea J Longley
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Shazia Ruybal-Pesantez
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Michael T White
- Institut Pasteur, Université de Paris Cité, G5 Épidémiologie et Analyse des Maladies Infectieuses, Département de Santé Globale, Paris, France
| | - Bernard N Kanoi
- Centre for Research in Infectious Diseases, Directorate of Research and Innovation, Mount Kenya University, Thika, Kenya
| | - Hikaru Nagaoka
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Benson Kiniboro
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Peter Siba
- Vector Borne Disease Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Takafumi Tsuboi
- Division of Cell-Free Sciences, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
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Cardona-Arias JA, Higuita Gutiérrez LF, Carmona-Fonseca J. Diagnostic Accuracy of a Thick Blood Smear Compared to qPCR for Malaria Associated with Pregnancy in Colombia. Trop Med Infect Dis 2023; 8:tropicalmed8020119. [PMID: 36828535 PMCID: PMC9959527 DOI: 10.3390/tropicalmed8020119] [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: 12/13/2022] [Revised: 01/17/2023] [Accepted: 01/20/2023] [Indexed: 02/17/2023] Open
Abstract
This study aimed to evaluate the accuracy of the thick blood smear (TBS) versus quantitative polymerase chain reaction (qPCR) for the diagnosis of malaria associated with pregnancy (MAP) caused by P. falciparum or P. vivax in Colombia in its gestational malaria (GM), placental malaria (PM), and congenital malaria (CM) forms as well as to compare its accuracy in different subgroups of pregnant women according to the presence of fever, anemia and a history of malaria. This was a diagnostic evaluation of 829 pregnant women, 579 placentas, 381 umbilical cord samples, and 221 neonatal peripheral blood samples. Accuracy was evaluated based on the parameters of sensitivity, specificity, predictive values, likelihood ratios, and validity index, with their 95% confidence intervals. The frequency of GM was 36% (n = 297/829), PM 27% (n = 159/579), and CM 16.5% (n = 63/381) in umbilical cord samples and 2% (n = 5/221) in neonatal peripheral blood samples. For GM, the sensitivity was 55%, with higher rates in those infected with P. vivax (68%), with a history of malaria (69%), and with fever (96%). These three subgroups presented the best results in terms of the negative likelihood ratio and validity index. For PM, sensitivity was 8%; in subgroup analyses in terms of species, symptomatology (anemia and fever), and history of malaria, it was 1-18%, and the negative likelihood ratio was >0.80 in all subgroups. No false positives were recorded in any of the subgroups. The TBS did not detect any cases of CM. This study found the TBS yielded satisfactory results in terms of diagnosing GM for P. vivax, pregnant women with previous malaria and febrile. It also showed that the TBS is not useful for diagnosing PM and CM. It is necessary to conduct surveillance of MAP with molecular methods in in groups where TBS is deficient (asymptomatic GM, P. falciparum, and pregnant women without history of malaria) to optimize the timely treatment of PM and CM, avoid the deleterious effects of MAP and achieve the malaria elimination goals in Colombia.
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Affiliation(s)
| | - Luis Felipe Higuita Gutiérrez
- Escuela de Microbiología, Universidad de Antioquia, Medellín 050010, Colombia
- Facultad de Medicina, Universidad Cooperativa de Colombia, Medellín 050010, Colombia
| | - Jaime Carmona-Fonseca
- Grupo Salud y Comunidad César Uribe Piedrahíta, Facultad de Medicina, Universidad de Antioquia, Medellín 050010, Colombia
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15
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Balcha F, Menna T, Lombamo F. Prevalence of asymptomatic malaria and associated factors among pregnant women at Boset District in East Shoa Zone, Oromia Region, Ethiopia: a cross-sectional study. Malar J 2023; 22:28. [PMID: 36698185 PMCID: PMC9878930 DOI: 10.1186/s12936-023-04460-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 01/17/2023] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Malaria infection during pregnancy is a significant public health problem that puts pregnant women at risk. Interruption of transmission of asymptomatic malaria among a population remained a challenge and the host serves as a reservoir for the malaria parasite; and is also recognized as a major barrier to malaria elimination. This study aimed to assess the prevalence of asymptomatic malaria and associated factors among pregnant women in the Boset District, East Shoa Zone, Oromia, Ethiopia. METHODS A community-based cross-sectional study was conducted to assess the prevalence of asymptomatic malaria and associated factors in pregnant women from February to March 2022. Using multistage sample techniques, 328 asymptomatic pregnant women were enrolled. Data were collected using a structured questionnaire. A rapid test and Giemsa-stained blood smear microscopy were used to diagnose Plasmodium infections. Epi info version 7 was used to code, enter, and clean data before being uploaded to SPSS version 25.0 for analysis. Bivariable and multivariable binary logistic regression were employed to find the associated factors. Variables in the multivariable model with a p-value < 0.05 were considered significantly associated with asymptomatic malaria. RESULTS Of the total 328 pregnant women who participated in this study, 9(2.74%) and 10(3.05%) were confirmed to be infected with Plasmodium species by microscopy and rapid diagnostic tests, respectively. Asymptomatic malaria during pregnancy was found to be significantly associated with not using an insecticide-treated bed net [(P = 0.002, AOR: 9.61; 95% CI (2.22-41.53)], lack of consultation and health education about malaria prevention during Antenatal care attendance [(P = 0.04, AOR: 4.05; 95% CI (1.02, 16.05)], and living close stagnant water [(P = 0.02, AOR: 4.43; 95% CI (1.17,16.82)]. CONCLUSIONS The current study showed that asymptomatic malaria is prevalent in pregnant women. Not using insecticide-treated bed nets, inadequate health education during antenatal care, and living close to stagnant water are significantly associated with malaria infection. Thus, using insecticide-treated bed nets, health education, and avoiding stagnant water from residential areas could play significant roles in preventing asymptomatic malaria among pregnant women in the study area.
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Affiliation(s)
- Fufa Balcha
- School of Public Health, Adama Hospital Medical College, Adama, Ethiopia
| | - Takele Menna
- grid.460724.30000 0004 5373 1026School of Public Health, St Paul’s Hospital Millennium Medical College, Addis Ababa, Ethiopia
| | - Fantu Lombamo
- grid.460724.30000 0004 5373 1026School of Public Health, St Paul’s Hospital Millennium Medical College, Addis Ababa, Ethiopia
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16
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Host susceptibility genes of asymptomatic malaria from South Central Timor, Eastern Indonesia. Parasitol Res 2023; 122:61-75. [PMID: 36284023 DOI: 10.1007/s00436-022-07696-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 10/14/2022] [Indexed: 01/11/2023]
Abstract
Host genetic factors, such as the genes for various cytokines and adhesion molecules, play a significant role in determining susceptibility to malaria infection. Polymorphisms in host genes have been correlated with malaria infection in both African and Asian regions. The purpose of this study was to investigate the association between both cytokine and adhesion molecule genotypes with susceptibility to malaria infection in humans. Ten cytokine polymorphism loci (IL4 + 33, IL4-590, IL6-174, IL10-1082, IL10-1035, IL12p40, TNF-238, TNF-308, TNF-1031, and TNF-β) and three adhesion molecule polymorphism loci (CD36 exon 10, ICAM-1 Kilifi, and ICAM-1 exon 6) were genotyped using PCR-RFLP analysis. We conducted this study on 178 asymptomatic malaria subjects and 122 uninfected subjects. Results showed that certain CD36 exon 10 and IL10-3575 polymorphisms were associated with asymptomatic infection. The heterozygous (GT) and homozygous (GG) genotypes for CD36 exon 10 are associated with an increased risk of malaria infection. On the other hand, the homozygous genotype (AA) for IL10-3575 reduced the risk of asymptomatic malaria infection. No significant differences were found for the other polymorphisms studied. We also found that a polymorphism in CD36 exon 10 was strongly associated with asymptomatic malaria caused specifically by Plasmodium vivax. These findings suggest that the G allele of CD36 exon 10 is associated with an increased risk of asymptomatic malaria infection. On the other hand, the genotype AA for IL10-3575 was associated with a reduced risk of malaria infection.
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Shamseddin J, Ghanbarnejad A, Zakeri A, Abedi F, Khojasteh S, Turki H. Molecular Method Is Essential to Identify Asymptomatic Malaria Reservoirs: A Successful Experience in the Malaria Elimination Program in Iran. Diagnostics (Basel) 2022; 12:diagnostics12123025. [PMID: 36553032 PMCID: PMC9777330 DOI: 10.3390/diagnostics12123025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 11/26/2022] [Accepted: 11/28/2022] [Indexed: 12/12/2022] Open
Abstract
Background: The accurate diagnosis of malaria cases, especially asymptotic and low-parasitemia patients, using robust molecular methods (nested-PCR) have been emphasized. The goal of this study was to detect active cases of malaria in areas with a history of local malaria transmission focusing on the use of molecular tools to ensure that the malaria elimination program has been implemented successfully. Methods: In this cross-sectional study, 816 blood samples were taken from immigrants and local residents of malaria-endemic areas in Hormozgan province, Iran. In order to identify asymptomatic malaria parasite reservoirs, the samples were examined using microscopic, RDT, and nested-PCR techniques. Results: About twelve positive asymptomatic malaria cases were identified when the molecular method (nested-PCR) was used. The positivity rates among immigrants and local residents were 2.07% and 0.93%, respectively. No positive cases were detected using microscopic and RDT methods. Conclusions: The finding of the research emphasize that in addition to microscopy and RDTs methods, sensitive molecular tools as a standard and essential strategy are needed in the diagnosis and detection of asymptomatic parasite reservoir.
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Affiliation(s)
- Jebreil Shamseddin
- Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas 7916613885, Iran
- Infectious and Tropical Diseases Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas 7919693116, Iran
| | - Amin Ghanbarnejad
- Social Determinants in Health Promotion Research Center, Hormozgan Health Institute, Hormozgan, University of Medical Sciences, Bandar Abbas 7919916753, Iran
| | - Abdoljabbar Zakeri
- Infectious and Tropical Diseases Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas 7919693116, Iran
- Social Determinants in Health Promotion Research Center, Hormozgan Health Institute, Hormozgan, University of Medical Sciences, Bandar Abbas 7919916753, Iran
| | - Farshid Abedi
- Infectious Diseases Research Center, Birjand University of Medical Sciences, Birjand 9717853577, Iran
| | - Shaghayegh Khojasteh
- Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas 7916613885, Iran
- Infectious and Tropical Diseases Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas 7919693116, Iran
| | - Habibollah Turki
- Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas 7916613885, Iran
- Infectious and Tropical Diseases Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas 7919693116, Iran
- Correspondence:
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Assefa A, Mohammed H, Anand A, Abera A, Sime H, Minta AA, Tadesse M, Tadesse Y, Girma S, Bekele W, Etana K, Alemayehu BH, Teka H, Dilu D, Haile M, Solomon H, Moriarty LF, Zhou Z, Svigel SS, Ezema B, Tasew G, Woyessa A, Hwang J, Murphy M. Therapeutic efficacies of artemether-lumefantrine and dihydroartemisinin-piperaquine for the treatment of uncomplicated Plasmodium falciparum and chloroquine and dihydroartemisinin-piperaquine for uncomplicated Plasmodium vivax infection in Ethiopia. Malar J 2022; 21:359. [PMID: 36451216 PMCID: PMC9714156 DOI: 10.1186/s12936-022-04350-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 10/27/2022] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Routine monitoring of anti-malarial drugs is recommended for early detection of drug resistance and to inform national malaria treatment guidelines. In Ethiopia, the national treatment guidelines employ a species-specific approach. Artemether-lumefantrine (AL) and chloroquine (CQ) are the first-line schizonticidal treatments for Plasmodium falciparum and Plasmodium vivax, respectively. The National Malaria Control and Elimination Programme in Ethiopia is considering dihydroartemisinin-piperaquine (DHA/PPQ) as an alternative regimen for P. falciparum and P. vivax. METHODS The study assessed the clinical and parasitological efficacy of AL, CQ, and DHA/PPQ in four arms. Patients over 6 months and less than 18 years of age with uncomplicated malaria mono-infection were recruited and allocated to AL against P. falciparum and CQ against P. vivax. Patients 18 years or older with uncomplicated malaria mono-infection were recruited and randomized to AL or dihydroartemisinin-piperaquine (DHA/PPQ) against P. falciparum and CQ or DHA/PPQ for P. vivax. Patients were followed up for 28 (for CQ and AL) or 42 days (for DHA/PPQ) according to the WHO recommendations. Polymerase chain reaction (PCR)-corrected and uncorrected estimates were analysed by Kaplan Meier survival analysis and per protocol methods. RESULTS A total of 379 patients were enroled in four arms (n = 106, AL-P. falciparum; n = 75, DHA/PPQ- P. falciparum; n = 142, CQ-P. vivax; n = 56, DHA/PPQ-P. vivax). High PCR-corrected adequate clinical and parasitological response (ACPR) rates were observed at the primary end points of 28 days for AL and CQ and 42 days for DHA/PPQ. ACPR rates were 100% in AL-Pf (95% CI: 96-100), 98% in CQ-P. vivax (95% CI: 95-100) at 28 days, and 100% in the DHA/PPQ arms for both P. falciparum and P. vivax at 42 days. For secondary endpoints, by day three 99% of AL-P. falciparum patients (n = 101) cleared parasites and 100% were afebrile. For all other arms, 100% of patients cleared parasites and were afebrile by day three. No serious adverse events were reported. CONCLUSION This study demonstrated high therapeutic efficacy for the anti-malarial drugs currently used by the malaria control programme in Ethiopia and provides information on the efficacy of DHA/PPQ for the treatment of P. falciparum and P. vivax as an alternative option.
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Affiliation(s)
- Ashenafi Assefa
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia. .,Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Hussein Mohammed
- grid.452387.f0000 0001 0508 7211Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Anjoli Anand
- grid.416738.f0000 0001 2163 0069Epidemic Intelligence Service, U.S. Centers for Disease Control and Prevention, Atlanta, GA USA ,grid.416738.f0000 0001 2163 0069Malaria Branch, U.S. Centers for Disease Control and Prevention, Atlanta, GA USA
| | - Adugna Abera
- grid.452387.f0000 0001 0508 7211Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Heven Sime
- grid.452387.f0000 0001 0508 7211Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Anna A. Minta
- grid.416738.f0000 0001 2163 0069Epidemic Intelligence Service, U.S. Centers for Disease Control and Prevention, Atlanta, GA USA ,grid.416738.f0000 0001 2163 0069Malaria Branch, U.S. Centers for Disease Control and Prevention, Atlanta, GA USA
| | | | | | - Samuel Girma
- ICAP at Columbia University, Addis Ababa, Ethiopia ,U.S. President’s Malaria Initiative, USA Agency for International Development, Addis Ababa, Ethiopia
| | - Worku Bekele
- World Health Organization, Addis Ababa, Ethiopia
| | - Kebede Etana
- grid.414835.f0000 0004 0439 6364Ethiopian Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | - Hiwot Teka
- U.S. President’s Malaria Initiative, USA Agency for International Development, Addis Ababa, Ethiopia
| | - Dereje Dilu
- grid.414835.f0000 0004 0439 6364Ethiopian Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Mebrahtom Haile
- grid.414835.f0000 0004 0439 6364Ethiopian Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Hiwot Solomon
- grid.414835.f0000 0004 0439 6364Ethiopian Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Leah F. Moriarty
- grid.416738.f0000 0001 2163 0069U.S. President’s Malaria Initiative, Malaria Branch, US Centers for Disease Control and Prevention, Atlanta, GA USA
| | - Zhiyong Zhou
- grid.416738.f0000 0001 2163 0069Malaria Branch, U.S. Centers for Disease Control and Prevention, Atlanta, GA USA
| | - Samaly Souza Svigel
- grid.416738.f0000 0001 2163 0069Malaria Branch, U.S. Centers for Disease Control and Prevention, Atlanta, GA USA
| | - Bryan Ezema
- grid.416738.f0000 0001 2163 0069Malaria Branch, U.S. Centers for Disease Control and Prevention, Atlanta, GA USA
| | - Geremew Tasew
- grid.452387.f0000 0001 0508 7211Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Adugna Woyessa
- grid.452387.f0000 0001 0508 7211Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Jimee Hwang
- grid.416738.f0000 0001 2163 0069U.S. President’s Malaria Initiative, Malaria Branch, US Centers for Disease Control and Prevention, Atlanta, GA USA
| | - Matthew Murphy
- grid.416738.f0000 0001 2163 0069U.S. President’s Malaria Initiative, Malaria Branch, US Centers for Disease Control and Prevention, Atlanta, GA USA
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Nainggolan IRA, Syafutri RD, Sinambela MN, Devina C, Handayani, Hasibuan BS, Chuangchaiya S, Divis PCS, Idris ZM, Permatasari R, Lubis IND. The presence of Plasmodium malariae and Plasmodium knowlesi in near malaria elimination setting in western Indonesia. Malar J 2022; 21:316. [PMCID: PMC9636705 DOI: 10.1186/s12936-022-04335-y] [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: 06/21/2022] [Accepted: 10/18/2022] [Indexed: 11/06/2022] Open
Abstract
Background Indonesia is progressing towards malaria elimination. To achieve this goal, intervention measures must be addressed to cover all Plasmodium species. Comprehensive control measures and surveillance programmes must be intensified. This study aims to determine the prevalence of microscopic and submicroscopic malaria in Langkat district, North Sumatera Province, Indonesia. Methods A cross-sectional survey was conducted in six villages in Langkat district, North Sumatera Province in June 2019. Data were recorded using a standardized questionnaire. Finger pricked blood samples were obtained for malaria examination using rapid diagnostic test, thick and thin blood smears, and polymerase chain reaction. Results A total of 342 individuals were included in the study. Of them, one (0.3%) had a microscopic Plasmodium malariae infection, no positive RDT examination, and three (0.9%) were positive for P. malariae (n = 1) and Plasmodium knowlesi (n = 2). The distribution of bed net ownership was owned by 40% of the study participants. The participants had a house within a radius of 100–500 m from the forest (86.3%) and had the housing material of cement floor (56.1%), a tin roof (82.2%), wooden wall (35.7%), bamboo wall (28.1%), and brick wall (21.6%). Conclusion Malaria incidence has substantially decreased in Langkat, North Sumatera, Indonesia. However, submicroscopic infection remains in the population and may contribute to further transmission. Surveillance should include the detection of microscopic undetected parasites, to enable the achievement of malaria elimination.
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Affiliation(s)
| | - Rycha Dwi Syafutri
- grid.413127.20000 0001 0657 4011Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Monica Nadya Sinambela
- grid.413127.20000 0001 0657 4011Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Clara Devina
- grid.413127.20000 0001 0657 4011Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Handayani
- grid.413127.20000 0001 0657 4011Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Beby Syofiani Hasibuan
- grid.413127.20000 0001 0657 4011Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Sriwipa Chuangchaiya
- grid.9723.f0000 0001 0944 049XDepartment of Community Health, Faculty of Public Health, Kasetsart University, Chalermphrakiat Sakon Nakhon Province Campus, 47000 Sakon Nakhon, Thailand
| | - Paul C. S. Divis
- grid.412253.30000 0000 9534 9846Malaria Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak Malaysia
| | - Zulkarnain Md Idris
- grid.412113.40000 0004 1937 1557Department of Parasitology and Medical Entomology, Faculty of Medicine, Universiti Kebangsaan Malaysia, 56000 Cheras, Kuala Lumpur, Malaysia
| | - Ranti Permatasari
- grid.413127.20000 0001 0657 4011Department of Clinical Pathology, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
| | - Inke Nadia Diniyanti Lubis
- grid.413127.20000 0001 0657 4011Department of Paediatrics, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155 Indonesia
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Omondi CJ, Otambo WO, Odongo D, Ochwedo KO, Otieno A, Onyango SA, Orondo P, Ondeto BM, Lee MC, Zhong D, Kazura JW, Githeko AK, Yan G. Asymptomatic and submicroscopic Plasmodium infections in an area before and during integrated vector control in Homa Bay, western Kenya. Malar J 2022; 21:272. [PMID: 36153552 PMCID: PMC9509636 DOI: 10.1186/s12936-022-04288-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 09/08/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Long-lasting insecticidal nets (LLINs) have been the primary vector control strategy until indoor residual spraying (IRS) was added in Homa Bay and Migori Counties in western Kenya. The objective of this study was to evaluate the impact of LLINs integrated with IRS on the prevalence of asymptomatic and submicroscopic Plasmodium infections in Homa Bay County. METHODS A two-stage cluster sampling procedure was employed to enroll study participants aged ≥ 6 months old. Four consecutive community cross-sectional surveys for Plasmodium infection were conducted in residents of Homa Bay county, Kenya. Prior to the start of the study, all study households received LLINs, which were distributed between June 2017 and March 2018. The first (February 2018) and second (June 2018) surveys were conducted before and after the first round of IRS (Feb-Mar 2018), while the third (February 2019) and fourth (June 2019) surveys were conducted before and after the second application of IRS (February-March 2019). Finger-prick blood samples were obtained to prepare thick and thin smears for microscopic determination and qPCR diagnosis of Plasmodium genus. RESULTS Plasmodium spp. infection prevalence by microscopy was 18.5% (113/610) before IRS, 14.2% (105/737) and 3.3% (24/720) after the first round of IRS and 1.3% (11/849) after the second round of IRS (p < 0.0001). Submicroscopic (blood smear negative, qPCR positive) parasitaemia reduced from 18.9% (115/610) before IRS to 5.4% (46/849) after IRS (p < 0.0001). However, the proportion of PCR positive infections that were submicroscopic increased from 50.4% (115/228) to 80.7% (46/57) over the study period (p < 0.0001). Similarly, while the absolute number and proportions of microscopy positives which were asymptomatic decreased from 12% (73/610) to 1.2% (9/849) (p < 0.0001), the relative proportion increased. Geometric mean density of P. falciparum parasitaemia decreased over the 2-year study period (p < 0.0001). CONCLUSIONS These data suggest that two annual rounds of IRS integrated with LLINs significantly reduced the prevalence of Plasmodium parasitaemia, while the proportion of asymptomatic and submicroscopic infections increased. To reduce cryptic P. falciparum transmission and improve malaria control, strategies aimed at reducing the number of asymptomatic and submicroscopic infections should be considered.
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Affiliation(s)
- Collince J Omondi
- Department of Biology, Faculty of Science and Technology, University of Nairobi, Nairobi, Kenya.
- Sub-Saharan International Center of Excellence for Malaria Research, Homa Bay, Kenya.
| | - Wilfred O Otambo
- Sub-Saharan International Center of Excellence for Malaria Research, Homa Bay, Kenya
- Department of Zoology, Maseno University, Kisumu, Kenya
| | - David Odongo
- Department of Biology, Faculty of Science and Technology, University of Nairobi, Nairobi, Kenya
| | - Kevin O Ochwedo
- Department of Biology, Faculty of Science and Technology, University of Nairobi, Nairobi, Kenya
- Sub-Saharan International Center of Excellence for Malaria Research, Homa Bay, Kenya
| | - Antony Otieno
- Department of Biology, Faculty of Science and Technology, University of Nairobi, Nairobi, Kenya
| | - Shirley A Onyango
- Sub-Saharan International Center of Excellence for Malaria Research, Homa Bay, Kenya
- Department of Zoological Sciences, School of Science and Technology, Kenyatta University, Nairobi, Kenya
| | - Pauline Orondo
- Sub-Saharan International Center of Excellence for Malaria Research, Homa Bay, Kenya
| | - Benyl M Ondeto
- Department of Biology, Faculty of Science and Technology, University of Nairobi, Nairobi, Kenya
- Sub-Saharan International Center of Excellence for Malaria Research, Homa Bay, Kenya
| | - Ming-Chieh Lee
- Sub-Saharan International Center of Excellence for Malaria Research, Homa Bay, Kenya
- Program in Public Health, College of Health Sciences, University of California, Irvine, CA, 92697, USA
| | - Daibin Zhong
- Program in Public Health, College of Health Sciences, University of California, Irvine, CA, 92697, USA
| | - James W Kazura
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Andrew K Githeko
- Sub-Saharan International Center of Excellence for Malaria Research, Homa Bay, Kenya
- Climate and Human Health Research Unit, Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Guiyun Yan
- Program in Public Health, College of Health Sciences, University of California, Irvine, CA, 92697, USA
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Komaki-Yasuda K, Kutsuna S, Kawaguchi M, Kamei M, Uchihashi K, Nakamura K, Nakamoto T, Ohmagari N, Kano S. Clinical performance testing of the automated haematology analyzer XN-31 prototype using whole blood samples from patients with imported malaria in Japan. Malar J 2022; 21:229. [PMID: 35907857 PMCID: PMC9338637 DOI: 10.1186/s12936-022-04247-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Accepted: 07/20/2022] [Indexed: 11/10/2022] Open
Abstract
Background The automated haematology analyzer XN-31 prototype (XN-31p) is a new flow cytometry-based device developed to measure the number and the ratio of malaria-infected red blood cells (MI-RBC) with a complete blood count (CBC). The XN-31p can provide results in about one minute and also can simultaneously provide information on the malaria parasite (Plasmodium) species. In this study, clinical testing of the XN-31p was performed using blood samples from patients with imported malaria in Japan. Methods Blood samples were collected from 80 patients who visited the hospital of the National Center for Global Health and Medicine, Tokyo, Japan, for malaria diagnosis from January 2017 to January 2019. The test results by the XN-31p were compared with those by other standard methods, such as microscopic observation, rapid diagnostic tests and the nested PCR. Results Thirty-three patients were diagnosed by the nested PCR as being malaria positive (28 Plasmodium falciparum, 2 Plasmodium vivax, 1 Plasmodium knowlesi, 1 mixed infection of P. falciparum and Plasmodium malariae, and 1 mixed infection of P. falciparum and Plasmodium ovale), and the other 47 were negative. The XN-31p detected 32 patients as “MI-RBC positive”, which almost matched the results by the nested PCR and, in fact, completely matched with the microscopic observations. The ratio of RBCs infected with malaria parasites as determined by the XN-31p showed a high correlation coefficient of more than 0.99 with the parasitaemia counted under microscopic observation. The XN-31p can analyse the size and nucleic acid contents of each cell, and the results were visualized on a two-dimensional cytogram termed the “M scattergram”. Information on species and developmental stages of the parasites could also be predicted from the patterns visualized in the M scattergrams. The XN-31p showed a positive coincidence rate of 0.848 with the nested PCR in discriminating P. falciparum from the other species. Conclusions The XN-31p could rapidly provide instructive information on the ratio of MI-RBC and the infecting Plasmodium species. It was regarded to be of great help for the clinical diagnosis of malaria. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04247-x.
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Affiliation(s)
- Kanako Komaki-Yasuda
- Department of Tropical Medicine and Malaria, Research Institute, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan
| | - Satoshi Kutsuna
- Disease Control and Prevention Center of National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan
| | - Miki Kawaguchi
- Sysmex Corporation, 4-4-4 Takatsukadai, Nishi-ku, Kobe, 651-2271, Japan
| | - Mina Kamei
- Sysmex Corporation, 4-4-4 Takatsukadai, Nishi-ku, Kobe, 651-2271, Japan
| | - Kinya Uchihashi
- Sysmex Corporation, 4-4-4 Takatsukadai, Nishi-ku, Kobe, 651-2271, Japan
| | - Keiji Nakamura
- Disease Control and Prevention Center of National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan
| | - Takato Nakamoto
- Disease Control and Prevention Center of National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan
| | - Norio Ohmagari
- Disease Control and Prevention Center of National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan
| | - Shigeyuki Kano
- Department of Tropical Medicine and Malaria, Research Institute, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan.
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Cao Y, Lu G, Zhou H, Wang W, Liu Y, Yang M, Liang C, Zhu G, Cao J. Case-based malaria surveillance and response: implementation of 1-3-7 approach in Jiangsu Province, China. ADVANCES IN PARASITOLOGY 2022; 116:1-31. [PMID: 35752445 DOI: 10.1016/bs.apar.2022.04.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Following initiation of China's National Malaria Elimination Action Plan (NMEAP) in 2010, China's 1-3-7 surveillance and response approach was developed and rolled out in China to facilitate the malaria control programme and accelerate the progress of malaria elimination. Innovative strategies and interventions have been developed and implemented in Jiangsu Province to facilitate case-based malaria surveillance and response. A total of 9879 malaria cases were reported in Jiangsu Province from 2001 to 2020. Since 2012, no indigenous malaria cases have been reported in Jiangsu Province. However, in recent years, there has been a substantial increase of imported cases from abroad. To continue improving the malaria surveillance and response system, Jiangsu Province has conducted population-based health education to improve the healthcare seeking behaviour of malaria patients, strengthened the capacity of health facilities to improve the performance of malaria diagnosis and treatment, and strengthened health workforce capacity to improve the implementation of 1-3-7 approach. Continually improving surveillance and response system can play a critical role in the early detection and rapid response of individual malaria cases and prevent the re-establishment of malaria.
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Affiliation(s)
- Yuanyuan Cao
- Key Laboratory of National Health Commission (NHC) on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, PR China
| | - Guangyu Lu
- School of Public Health, Medical College of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, PR China
| | - Huayun Zhou
- Key Laboratory of National Health Commission (NHC) on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, PR China
| | - Weiming Wang
- Key Laboratory of National Health Commission (NHC) on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, PR China
| | - Yaobao Liu
- Key Laboratory of National Health Commission (NHC) on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, PR China
| | - Mengmeng Yang
- Key Laboratory of National Health Commission (NHC) on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, PR China
| | - Cheng Liang
- Key Laboratory of National Health Commission (NHC) on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, PR China
| | - Guoding Zhu
- Key Laboratory of National Health Commission (NHC) on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, PR China; Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, PR China.
| | - Jun Cao
- Key Laboratory of National Health Commission (NHC) on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, PR China; Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, PR China.
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Melese Y, Alemu M, Yimer M, Tegegne B, Tadele T. Asymptomatic Malaria in Households and Neighbors of Laboratory Confirmed Cases in Raya Kobo District, Northeast Ethiopia. Ethiop J Health Sci 2022; 32:623-630. [PMID: 35813680 PMCID: PMC9214748 DOI: 10.4314/ejhs.v32i3.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 02/13/2022] [Indexed: 11/17/2022] Open
Abstract
Background Malaria is the leading vector-borne parasitic disease that is causing high morbidity and mortality worldwide. So far huge efforts to control and eliminate malaria are hindered by the occurrence of asymptomatic carriers that are a potential source of infection. Yet, there is a scarcity of data nationally and in the current study area as well. Therefore, this study was aimed to assess the prevalence of asymptomatic malaria in Northeast Ethiopia. Methods A community-based cross-sectional study was conducted in 2019 involving a total of 270 study participants recruited via purposive non-probability sampling technique. A structured questionnaire was used to collect data on sociodemographic characteristics, individual and household factors related to asymptomatic malaria. Data were entered in Epi Data 3.1 version and analyzed by using SPSS version 20, and p< 0.05 was considered statistically significant. Results The overall prevalence of asymptomatic malaria was 7.0%, with 3.0%, 5.2%, and 12.0%, respectively by Rapid diagnostic tests (RDT), Microscopy and Polymerase chain reaction (PCR). The majority of infections (73.7%) were identified from index households. Previous malaria history (AOR: 4.030, 95% CI: 1.021-15.903), living with index cases (AOR: 3.880, 95% CI: 1.275-11.806) and family size > 6 members (AOR: 4.820, 95% CI: 1.260-18.437) were significant predictors of asymptomatic malaria. Conclusion Reactive case detection had identified considerably higher asymptomatic malaria cases in the community. Therefore, active case investigation should be established in the community by tracking the symptomatic cases at the health facilities.
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Affiliation(s)
| | - Megbaru Alemu
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Bahir Dar University, Ethiopia
| | - Mulat Yimer
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Bahir Dar University, Ethiopia
| | | | - Tigist Tadele
- Department of Biomedical Sciences, College of Medicine and Health Sciences, Bahir Dar University, Ethiopia
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Delineating charge and capacitance transduction in system-integrated graphene-based BioFETs used as aptasensors for malaria detection. Biosens Bioelectron 2022; 208:114219. [DOI: 10.1016/j.bios.2022.114219] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 03/22/2022] [Accepted: 03/23/2022] [Indexed: 12/19/2022]
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25
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Nega D, Abera A, Gidey B, Mekasha S, Abebe A, Dillu D, Mehari D, Assefa G, Hailu S, Haile M, Etana K, Solomon H, Tesfaye G, Nigatu D, Destaw Z, Tesfaye B, Serda B, Yeshiwondim A, Getachew A, Teka H, Nahusenay H, Abdelmenan S, Reda H, Bekele W, Zewdie A, Tollera G, Assefa A, Tasew G, Woyessa A, Abate E. Baseline malaria prevalence at the targeted pre-elimination districts in Ethiopia. BMC Public Health 2021; 21:1996. [PMID: 34732150 PMCID: PMC8567662 DOI: 10.1186/s12889-021-12036-5] [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: 01/28/2021] [Accepted: 10/18/2021] [Indexed: 12/05/2022] Open
Abstract
Background Encouraged by the previous success in malaria control and prevention strategies, the Ethiopian ministry of health launched malaria elimination with a stepwise approach by primarily targeting the low-transmission Districts and their adjacent areas/zones in order to shrink the country’s malaria map progressively. Hence, this community survey was conducted to establish baseline malaria information at the preliminary phase of elimination at targeted settings. Methods A community-based cross-sectional survey was conducted at 20 malaria-elimination targeted Districts selected from five Regional states and one city administration in Ethiopia. The GPS-enabled smartphones programmed with Open Data Kit were used to enumerate 9326 study households and collect data from 29,993 residents. CareStart™ Malaria PAN (pLDH) Rapid Diagnostic Tests (RDTs) were used for blood testing at the field level. Armpit digital thermometers were used to measure axillary temperature. Result Overall malaria prevalence by RDTs was 1.17% (339/28973). The prevalence at District levels ranged from 0.0 to 4.7%. The proportion of symptomatic cases (axillary temperature > 37.5oc) in the survey was 9.2% (2760/29993). Among the 2510 symptomatic individuals tested with RDTs, only 3.35% (84/2510) were malaria positive. The 75.2% (255/339) of all malaria positives were asymptomatic. Of the total asymptomatic malaria cases, 10.2% (26/255) were under-five children and 89.8% (229/255) were above 5 years of age. Conclusion The study shows a decrease in malaria prevalence compared to the reports of previous malaria indicator surveys in the country. The finding can be used as a baseline for measuring the achievement of ongoing malaria elimination efforts. Particularly, the high prevalence of asymptomatic individuals (0.88%) in these transmission settings indicates there may be sustaining hidden transmission. Therefore, active case detection with more sensitive diagnostic techniques is suggested to know more real magnitude of residual malaria in the elimination-targeted areas.
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Affiliation(s)
- Desalegn Nega
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia.
| | - Adugna Abera
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | | | - Sindew Mekasha
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Abnet Abebe
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Dereje Dillu
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Degu Mehari
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | - Samuel Hailu
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | - Kebede Etana
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | | | | | - Zelalem Destaw
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Berhane Tesfaye
- Malaria Control and Elimination Partnership in Africa (MACEPA) at PATH, Addis Ababa, Ethiopia
| | - Belendia Serda
- Malaria Control and Elimination Partnership in Africa (MACEPA) at PATH, Addis Ababa, Ethiopia
| | - Asnakew Yeshiwondim
- Malaria Control and Elimination Partnership in Africa (MACEPA) at PATH, Addis Ababa, Ethiopia
| | - Assefaw Getachew
- Malaria Control and Elimination Partnership in Africa (MACEPA) at PATH, Addis Ababa, Ethiopia
| | - Hiwot Teka
- President's Malaria Initiative (PMI), Addis Ababa, Ethiopia
| | | | | | - Hailemariam Reda
- Clinton Health Access Initiative, Inc. (CHAI), Addis Ababa, Ethiopia
| | - Worku Bekele
- World Health Organization (WHO), Addis Ababa, Ethiopia
| | - Ayele Zewdie
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
| | | | | | - Geremew Tasew
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Adugna Woyessa
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Ebba Abate
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
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Hayuma PM, Wang CW, Liheluka E, Baraka V, Madebe RA, Minja DTR, Misinzo G, Alifrangis M, Lusingu JPA. Prevalence of asymptomatic malaria, submicroscopic parasitaemia and anaemia in Korogwe District, north-eastern Tanzania. Malar J 2021; 20:424. [PMID: 34715886 PMCID: PMC8555315 DOI: 10.1186/s12936-021-03952-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 10/13/2021] [Indexed: 11/21/2022] Open
Abstract
Background Asymptomatic malaria infections largely remain undetected and act as a reservoir for continuous transmission. The study assessed the prevalence of submicroscopic asymptomatic malaria infections and anaemia in two rural low (300 m above sea level) and highland (700 m asl) settings of Korogwe District north-eastern Tanzania. Methods A cross-sectional malariometric survey involving individuals aged 0–19 years was conducted in June 2018 in the two rural villages. Venous blood was collected from eligible study participants for estimation of haemoglobin level, detection of malaria by rapid diagnostic test (RDT), quantification of malaria parasitaemia by microscopy, as well as dried blood spot (DBS) for determining submicroscopic infections by PCR targeting the small subunit of the ribosomal ribonucleic acid (ssrRNA) of human Plasmodium. Results Out of 565 individuals tested, 211 (37.3%) were malaria positive based on RDT, whereas only 81 (14.3%) were positive by microscopy. There was no significant difference in the prevalence between the highland and the lowland village, p = 0.19 and p = 0.78 microscopy and RDT, respectively. Three out of 206 (1.5%) RDT/microscopy negative samples were P. falciparum positive by PCR. Of the 211 RDT and 81 microscopy positive, 130 (61.6%) and 33 (40.7%), respectively, were defined as being asymptomatic. Of the 565 individuals, 135 (23.9%) were anaemic (haemoglobin < 11 g/dL) out of which 5.2% were severely anaemic. The risk of being anaemic was significantly higher among individuals with asymptomatic malaria as compared to those without malaria as confirmed by RDT (AOR = 2.06 (95% CI 1.32–3.20) while based on microscopic results there was no significant differences observed (AOR = 2.09, 95% CI 0.98–4.47). Age and altitude had no effect on the risk of anaemia even after adjusting for asymptomatic malaria. Conclusions Asymptomatic malaria is associated with an increased risk of having anaemia in the study communities. The findings highlight the need for targeted interventions focusing on asymptomatic infections which is an important risks factor for anaemia in the community and act as a source of continued transmission of malaria in the study area.
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Affiliation(s)
- Paul M Hayuma
- National Institute for Medical Research, Tanga Research Centre, P. O. Box 5004, Tanga, Tanzania. .,Department of Veterinary Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, P. O. Box 3019, Morogoro, Tanzania.
| | - Christian W Wang
- Department of Immunology and Microbiology, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - Edwin Liheluka
- National Institute for Medical Research, Tanga Research Centre, P. O. Box 5004, Tanga, Tanzania
| | - Vito Baraka
- National Institute for Medical Research, Tanga Research Centre, P. O. Box 5004, Tanga, Tanzania
| | - Rashid A Madebe
- National Institute for Medical Research, Tanga Research Centre, P. O. Box 5004, Tanga, Tanzania
| | - Daniel T R Minja
- National Institute for Medical Research, Tanga Research Centre, P. O. Box 5004, Tanga, Tanzania
| | - Gerald Misinzo
- Department of Veterinary Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, P. O. Box 3019, Morogoro, Tanzania.,SACIDS Africa Centre of Excellence for Infectious Diseases, SACIDS Foundation for One Health, Sokoine University of Agriculture, P. O. Box 3297, Morogoro, Tanzania
| | - Michael Alifrangis
- Department of Immunology and Microbiology, Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
| | - John P A Lusingu
- National Institute for Medical Research, Tanga Research Centre, P. O. Box 5004, Tanga, Tanzania
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Leonard CM, Assefa A, Sime H, Mohammed H, Kebede A, Solomon H, Drakeley C, Murphy M, Hwang J, Rogier E. Spatial distribution of Plasmodium falciparum and P. vivax in northern Ethiopia by microscopy, rapid diagnostic test, laboratory antibody and antigen data. J Infect Dis 2021; 225:881-890. [PMID: 34628501 DOI: 10.1093/infdis/jiab489] [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: 06/14/2021] [Accepted: 09/28/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Determining malaria transmission within regions of low, heterogenous prevalence is difficult. A variety of malaria tests exist and range from identification of diagnostic infection to testing for prior exposure. This study describes concordance of multiple malaria tests using data from a 2015 household survey conducted in Ethiopia. METHODS Blood samples (n= 2,279) from three regions in northern Ethiopia were assessed for Plasmodium falciparum and P. vivax by microscopy, rapid diagnostic test (RDT), multiplex antigen assay, and multiplex assay for IgG antibodies. Geospatial analysis was conducted with spatial scan statistics and kernel density estimation to identify hotspots of malaria by different test results. RESULTS Prevalence of malaria infection was low (1.4% by RDT, 1.0% by microscopy, and 1.8% by laboratory antigen assay). For P. falciparum, overlapping spatial clusters for all tests and an additional five unique IgG clusters were identified. For P. vivax, clusters identified for bead antigen assay, microscopy, and IgG with partial overlap. CONCLUSIONS Assessing the spatial distribution of malaria exposure using multiple metrics can improve the understanding of malaria transmission dynamics in a region. The relative abundance of antibody clusters indicates that in areas of low-transmission, IgG antibodies are a more useful marker to assess malaria exposure.
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Affiliation(s)
- Colleen M Leonard
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Ashenafi Assefa
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia.,Infectious Disease ecology and epidemiology lab, University of North Carolina at Chapel Hill, USA
| | - Heven Sime
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | | | - Amha Kebede
- African Society for Laboratory Medicine, Addis Ababa, Ethiopia
| | - Hiwot Solomon
- Ethiopian Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Chris Drakeley
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matt Murphy
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA.,U.S. President's Malaria Initiative, Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Jimee Hwang
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA.,U.S. President's Malaria Initiative, Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Eric Rogier
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, USA
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Alves JRS, de Araújo FF, Pires CV, Teixeira-Carvalho A, Lima BAS, Torres LM, Ntumngia FB, Adams JH, Kano FS, Carvalho LH. Multiplexed Microsphere-Based Flow Cytometric Assay to Assess Strain Transcending Antibodies to Plasmodium vivax Duffy Binding Protein II Reveals an Efficient Tool to Identify Binding-Inhibitory Antibody Responders. Front Immunol 2021; 12:704653. [PMID: 34675915 PMCID: PMC8523986 DOI: 10.3389/fimmu.2021.704653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 09/13/2021] [Indexed: 11/24/2022] Open
Abstract
Malaria remains a major public health problem worldwide, and Plasmodium vivax is the most widely distributed malaria parasite. Naturally acquired binding inhibitory antibodies (BIAbs) to region II of the Duffy binding protein (DBPII), a P. vivax ligand that is critical for reticulocyte invasion, are associated with a reduced risk of clinical malaria. Owing to methodological issues in evaluating antibodies that inhibit the DBPII-DARC interaction, a limited number of studies have investigated DBPII BIAbs in P. vivax-exposed populations. Based on the assumption that individuals with a consistent BIAb response are characterized by strain-transcending immune responses, we hypothesized that detecting broadly reactive DBPII antibodies would indicate the presence of BIAb response. By taking advantage of an engineered DBPII immunogen targeting conserved DBPII neutralizing epitopes (DEKnull-2), we standardized a multiplex flow cytometry-based serological assay to detect broadly neutralizing IgG antibodies. For this study, a standard in vitro cytoadherence assay with COS-7 cells expressing DBPII was used to test for DBPII BIAb response in long-term P. vivax-exposed Amazonian individuals. Taken together, the results demonstrate that this DBPII-based multiplex assay facilitates identifying DBPII BIAb carriers. Of relevance, the ability of the multiplex assay to identify BIAb responders was highly accurate when the positivity for all antigens was considered. In conclusion, the standardized DBPII-based flow cytometric assay confirmed that DBPII-BIAb activity was associated with the breadth rather than the magnitude of anti-DBPII antibodies. Altogether, our results suggest that multiplex detection of broadly DBPII-reactive antibodies facilitates preliminary screening of BIAb responders.
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Affiliation(s)
- Jéssica R. S. Alves
- Molecular Biology and Malaria Immunology, René Rachou Institute, Oswaldo Cruz Foundation (FIOCRUZ), Belo Horizonte, Brazil
| | - Fernanda F. de Araújo
- Integrated Research Group in Biomarkers, René Rachou Institute, Oswaldo Cruz Foundation (FIOCRUZ), Belo Horizonte, Brazil
| | - Camilla V. Pires
- Center for Global Health and Infectious Diseases Research, Department of Global Health, College of Public Health, University of South Florida, Tampa, FL, United States
| | - Andréa Teixeira-Carvalho
- Integrated Research Group in Biomarkers, René Rachou Institute, Oswaldo Cruz Foundation (FIOCRUZ), Belo Horizonte, Brazil
| | - Barbara A. S. Lima
- Molecular Biology and Malaria Immunology, René Rachou Institute, Oswaldo Cruz Foundation (FIOCRUZ), Belo Horizonte, Brazil
| | - Letícia M. Torres
- Molecular Biology and Malaria Immunology, René Rachou Institute, Oswaldo Cruz Foundation (FIOCRUZ), Belo Horizonte, Brazil
| | - Francis B. Ntumngia
- Center for Global Health and Infectious Diseases Research, Department of Global Health, College of Public Health, University of South Florida, Tampa, FL, United States
| | - John H. Adams
- Center for Global Health and Infectious Diseases Research, Department of Global Health, College of Public Health, University of South Florida, Tampa, FL, United States
| | - Flora S. Kano
- Molecular Biology and Malaria Immunology, René Rachou Institute, Oswaldo Cruz Foundation (FIOCRUZ), Belo Horizonte, Brazil
| | - Luzia H. Carvalho
- Molecular Biology and Malaria Immunology, René Rachou Institute, Oswaldo Cruz Foundation (FIOCRUZ), Belo Horizonte, Brazil
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Abstract
J. Kevin Baird and colleagues, examine and discuss the estimated global burden of vivax malaria and it's biological, clinical, and public health complexity.
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Affiliation(s)
- Katherine E. Battle
- Institute for Disease Modeling, Seattle, Washington, United States of America
| | - J. Kevin Baird
- Eijkman-Oxford Clinical Research Unit, Eijkman Institute of Molecular Biology, Jakarta, Indonesia
- Nuffield Department of Medicine, Centre for Tropical Medicine, University of Oxford, Oxford, United Kingdom
- * E-mail:
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30
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Subpatent Plasmodium with mutant pfmdr1, pfcrt, and pvmdr1 alleles from endemic provinces in Mindanao, the Philippines: implications for local malaria elimination. Int J Infect Dis 2021; 110:45-53. [PMID: 34157387 DOI: 10.1016/j.ijid.2021.06.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES This study was performed to identify and characterize circulating Plasmodium species in three provinces of Mindanao approaching malaria elimination. METHODS Rapid diagnostic tests (RDT), microscopic examination, and PCR were used to detect malaria parasites. PCR-positive isolates were genotyped for polymorphisms in loci of interest. RESULTS A total of 2639 participants were surveyed in Mindanao between 2010 and 2013. Malaria prevalence by PCR was 3.8% (95% confidence interval (CI): 2.7-5.2%) in Sarangani, 10% (95% CI: 7.7-12.7%) in South Cotabato, and 4.2% (95% CI: 3.2-5.6%) in Tawi-Tawi. P. falciparum and P. vivax were identified in all three provinces, and there was one case of P. malariae in South Cotabato. RDT was inferior to PCR for detecting asymptomatic P. falciparum and P. vivax. In Tawi-Tawi, microscopy failed to identify 46 PCR-positive malaria infections. The presence of pfcrt haplotypes CVMNK, CVIET, and SMNT (codons 72-76), pfmdr1 haplotype NFSND (codons 86, 184, 1034, 1042, 1246), and pvmdr1 haplotype NFL (codons 91, 976, 1076) was confirmed in Mindanao. CONCLUSIONS Asymptomatic Plasmodium infections persisted in local communities between 2010 and 2013. PCR successfully identified subpatent malaria infections, and can better characterize malaria epidemiology in communities seeking malaria control and elimination at the local level.
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Abdulraheem MA, Ernest M, Ugwuanyi I, Abkallo HM, Nishikawa S, Adeleke M, Orimadegun AE, Culleton R. High prevalence of Plasmodium malariae and Plasmodium ovale in co-infections with Plasmodium falciparum in asymptomatic malaria parasite carriers in southwestern Nigeria. Int J Parasitol 2021; 52:23-33. [PMID: 34390743 DOI: 10.1016/j.ijpara.2021.06.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 04/23/2021] [Accepted: 06/03/2021] [Indexed: 12/31/2022]
Abstract
Asymptomatic malaria parasite carriers do not seek anti-malarial treatment and may constitute a silent infectious reservoir. In order to assess the level of asymptomatic and symptomatic carriage amongst adolescents in a highly endemic area, and to identify the risk factors associated with such carriage, we conducted a cross-sectional survey of 1032 adolescents (ages 10-19 years) from eight schools located in Ibadan, southwestern Nigeria in 2016. Blood films and blood spot filter paper samples were prepared for microscopy and DNA analysis. The prevalence of asymptomatic malaria was determined using microscopy, rapid diagnostic tests and PCR for 658 randomly selected samples. Of these, we found that 80% of asymptomatic schoolchildren were positive for malaria parasites by PCR, compared with 47% and 9%, determined by rapid diagnostic tests and microscopy, respectively. Malaria parasite species typing was performed using PCR targeting the mitochondrial CoxIII gene, and revealed high rates of carriage of Plasmodium malariae (53%) and Plasmodium ovale (24%). Most asymptomatic infections were co-infections of two or more species (62%), with Plasmodium falciparum + P. malariae the most common (35%), followed by P. falciparum + P. malariae + P. ovale (21%) and P. falciparum + P. ovale (6%). Single infections of P. falciparum, P. malariae and P. ovale accounted for 24%, 10% and 4% of all asymptomatic infections, respectively. To compare the species composition of asymptomatic and symptomatic infections, further sample collection was carried out in 2017 at one of the previously sampled schools, and at a nearby hospital. Whilst the species composition of the asymptomatic infections was similar to that observed in 2016, the symptomatic infections were markedly different, with single infections of P. falciparum observed in 91% of patients, P. falciparum + P. malariae in 5% and P. falciparum + P. ovale in 4%.
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Affiliation(s)
- Muhydeen Abiodun Abdulraheem
- Malaria Unit, Department of Pathology, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Diana Princess of Wales Hospital, Grimsby, Northeast Lincolnshire, United Kingdom
| | - Medard Ernest
- Malaria Unit, Department of Pathology, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, United States
| | - Ifeoma Ugwuanyi
- Malaria Unit, Department of Pathology, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; University of New South Wales (UNSW), Sydney, Australia
| | - Hussein M Abkallo
- Malaria Unit, Department of Pathology, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi 00100 Kenya
| | - Saori Nishikawa
- Graduate School of Social and Cultural Science, Kumamoto University, Japan
| | | | | | - Richard Culleton
- Malaria Unit, Department of Pathology, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Department of Protozoology, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Division of Molecular Parasitology, Proteo-Science Centre, Ehime University, Shitsukawa, Toon, Ehime 791-0295, Japan.
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Prusty D, Gupta N, Upadhyay A, Dar A, Naik B, Kumar N, Prajapati VK. Asymptomatic malaria infection prevailing risks for human health and malaria elimination. INFECTION GENETICS AND EVOLUTION 2021; 93:104987. [PMID: 34216796 DOI: 10.1016/j.meegid.2021.104987] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 06/23/2021] [Accepted: 06/27/2021] [Indexed: 01/09/2023]
Abstract
There has been a consistent rise in malaria cases in the last few years. The existing malaria control measures are challenged by insecticide resistance in the mosquito vector, drug résistance in parasite populations, and asymptomatic malaria (ASM) in healthy individuals. The absence of apparent malaria symptoms and the presence of low parasitemia makes ASM a hidden reservoir for malaria transmission and an impediment in malaria elimination efforts. This review focuses on ASM in malaria-endemic countries and the past and present research trends from those geographical locations. The harmful impacts of asymptomatic malaria on human health and its contribution to disease transmission are highlighted. We discuss certain crucial genetic changes in the parasite and host immune response necessary for maintaining low parasitemia leading to long-term parasite survival in the host. Since the chronic health effects and the potential roles for disease transmission of ASM remain mostly unknown to significant populations, we offer proposals for developing general awareness. We also suggest advanced technology-based diagnostic methods, and treatment strategies to eliminate ASM.
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Affiliation(s)
- Dhaneswar Prusty
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India.
| | - Nidhi Gupta
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India
| | - Arun Upadhyay
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India
| | - Ashraf Dar
- Department of Biochemistry, University of Kashmir, Hazaratbal, Srinagar 190006, Jammu and Kashmir, India
| | - Biswajit Naik
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India
| | - Navin Kumar
- School of Biotechnology, Gautam Buddha University, Greater Noida, 201308, UP, India
| | - Vijay Kumar Prajapati
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India
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Russell TL, Grignard L, Apairamo A, Kama N, Bobogare A, Drakeley C, Burkot TR. Getting to zero: micro-foci of malaria in the Solomon Islands requires stratified control. Malar J 2021; 20:248. [PMID: 34090430 PMCID: PMC8180101 DOI: 10.1186/s12936-021-03779-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/22/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Solomon Islands has made significant progress in the control of malaria through vector control, access and use of improved diagnostics and therapeutic drugs. As transmission is reduced there is a need to understand variations in transmission risk at the provincial and village levels to stratify control methods. METHODS A cross-sectional survey of malaria in humans was conducted in the Solomon Islands during April 2018. Nineteen villages across 4 provinces were included. The presence of Plasmodium species parasites in blood samples was detected using PCR. RESULTS Blood samples were analysed from 1,914 participants. The prevalence of DNA of Plasmodium falciparum was 1.2 % (n = 23) and for Plasmodium vivax was 1.5 % (n = 28). 22 % (n = 5/23) of P. falciparum DNA positive participants were febrile and 17 % of P. vivax DNA positive participants (n = 5/28). The prevalence of both P. falciparum and P. vivax was extremely spatially heterogeneous. For P. falciparum, in particular, only 2 small foci of transmission were identified among 19 villages. Plasmodium falciparum infections were uniformly distributed across age groups. Insecticide-treated bed net use the night prior to the survey was reported by 63 % of participants and significantly differed by province. CONCLUSIONS Malaria transmission across the Solomon Islands has become increasingly fragmented, affecting fewer villages and provinces. The majority of infections were afebrile suggesting the need for strong active case detection with radical cure with primaquine for P. vivax. Village-level stratification of targeted interventions based on passive and active case detection data could support the progress towards a more cost-effective and successful elimination programme.
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Affiliation(s)
- Tanya L Russell
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia.
| | - Lynn Grignard
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Alan Apairamo
- National Vector Borne Disease Control Programme, Ministry of Health and Medical Services, Honiara, Solomon Islands
| | - Nathan Kama
- National Vector Borne Disease Control Programme, Ministry of Health and Medical Services, Honiara, Solomon Islands
| | - Albino Bobogare
- National Vector Borne Disease Control Programme, Ministry of Health and Medical Services, Honiara, Solomon Islands
| | - Chris Drakeley
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Thomas R Burkot
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia
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Shankar H, Singh MP, Phookan S, Singh K, Mishra N. Diagnostic performance of rapid diagnostic test, light microscopy and polymerase chain reaction during mass survey conducted in low and high malaria-endemic areas from two North-Eastern states of India. Parasitol Res 2021; 120:2251-2261. [PMID: 33772349 PMCID: PMC7997798 DOI: 10.1007/s00436-021-07125-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 03/15/2021] [Indexed: 11/25/2022]
Abstract
An early and accurate diagnosis followed by prompt treatment is pre-requisite for the management of any disease. Malaria diagnosis is routinely performed by microscopy and rapid diagnostic tests (RDTs) in the field settings; however, their performance may vary across regions, age and asymptomatic status. Owing to this, we assessed the diagnostic performance of conventional and advanced molecular tools for malaria detection in low and high malaria-endemic settings. We performed mass blood surveys in low and high endemic regions of two North-Eastern districts from the states of Assam and Meghalaya. A total of 3322 individuals were screened for malaria using RDT, microscopy and PCR and measures of diagnostic accuracy were estimated. Out of 3322 individuals, 649 (19.5%) were detected with malaria parasite. Asymptomatic were 86.4% (2872/3322), of which 19.4% (557/2872) had Plasmodium infection. The sensitivity and specificity of microscopy were 42.7% and 99.3%, and RDT showed 49.9% and 90.4%, respectively, considering PCR as standard. RDT (AUC: 0.65 vs 0.74; p = 0.001) and microscopy (AUC: 0.64 vs 0.76; p < 0.0001) performances were significantly lower in low compared to high endemic areas. True positive rate was lower in asymptomatics but true negative rate was found similar to symptomatic individuals. The conventional diagnostic tools (RDT and microscopy) had detected malaria in children with nearly twofold greater sensitivity than in the adults (p < 0.05). To conclude, asymptomatics, adults and low malaria-endemic regions require major attention due to mediocre performance of conventional diagnostic tools in malaria detection.
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Affiliation(s)
- Hari Shankar
- Parasite-Host Biology Group, ICMR-National Institute of Malaria Research, Sector-8, Dwarka, New Delhi, 110077, India
| | - Mrigendra Pal Singh
- Parasite-Host Biology Group, ICMR-National Institute of Malaria Research, Sector-8, Dwarka, New Delhi, 110077, India
| | - Sobhan Phookan
- ICMR-National Institute of Malaria Research Field Unit, Guwahati, Assam, 781022, India
| | - Kuldeep Singh
- ICMR-National Institute of Malaria Research Field Unit, Guwahati, Assam, 781022, India
| | - Neelima Mishra
- Parasite-Host Biology Group, ICMR-National Institute of Malaria Research, Sector-8, Dwarka, New Delhi, 110077, India.
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Auburn S, Cheng Q, Marfurt J, Price RN. The changing epidemiology of Plasmodium vivax: Insights from conventional and novel surveillance tools. PLoS Med 2021; 18:e1003560. [PMID: 33891580 PMCID: PMC8064506 DOI: 10.1371/journal.pmed.1003560] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Sarah Auburn and co-authors discuss the unique biology and epidemiology of P. vivax and current evidence on conventional and new approaches to surveillance.
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Affiliation(s)
- Sarah Auburn
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
| | - Qin Cheng
- Department of Drug Resistance and Diagnostics, Australian Defence Force Malaria and Infectious Disease Institute, Brisbane, Australia
- The Australian Defence Force Malaria and Infectious Disease Institute Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Jutta Marfurt
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | - Ric N. Price
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
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McCaffery JN, Singh B, Nace D, Moreno A, Udhayakumar V, Rogier E. Natural infections with different Plasmodium species induce antibodies reactive to a chimeric Plasmodium vivax recombinant protein. Malar J 2021; 20:86. [PMID: 33579292 PMCID: PMC7880512 DOI: 10.1186/s12936-021-03626-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/04/2021] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND As malaria incidence and transmission in a region decreases, it becomes increasingly difficult to identify areas of active transmission. Improved methods for identifying and monitoring foci of active malaria transmission are needed in areas of low parasite prevalence in order to achieve malaria elimination. Serological assays can provide population-level infection history to inform elimination campaigns. METHODS A bead-based multiplex antibody detection assay was used to evaluate a chimeric Plasmodium vivax MSP1 protein (PvRMC-MSP1), designed to be broadly immunogenic for use in vaccine studies, to act as a pan-malaria serological tool based on its ability to capture IgG in plasma samples obtained from naturally exposed individuals. Samples from 236 US travellers with PCR confirmed infection status from all four major Plasmodium species infecting humans, Plasmodium falciparum (n = 181), Plasmodium vivax (n = 38), Plasmodium malariae (n = 4), and Plasmodium ovale (n = 13) were tested for IgG capture using PvRMC-MSP1 as well as the four recombinant MSP1-19 kD isoforms representative of these Plasmodium species. RESULTS Regardless of infecting Plasmodium species, a large proportion of plasma samples from infected US travellers provided a high assay signal to the PvRMC-MSP1 chimeric protein, with 115 high responders out of 236 samples assessed (48.7%). When grouped by active infection, 38.7% P. falciparum-, 92.1% of P. vivax-, 75.0% P. malariae-, and 53.4% of P. ovale-infected individuals displayed high assay signals in response to PvRMC-MSP1. It was also determined that plasma from P. vivax-infected individuals produced increased assay signals in response to the PvRMC-MSP1 chimera as compared to the recombinant PvMSP1 for 89.5% (34 out of 38) of individuals. PvRMC-MSP1 also showed improved ability to capture IgG antibodies from P. falciparum-infected individuals when compared to the capture by recombinant PvMSP1, with high assay signals observed for 38.7% of P. falciparum-infected travellers in response to PvRMC-MSP1 IgG capture compared to just 1.1% who were high responders to capture by the recombinant PvMSP1 protein. CONCLUSIONS These results support further study of designed antigens as an approach for increasing sensitivity or broadening binding capacity to improve existing serological tools for determining population-level exposure to Plasmodium species. Including both broad-reacting and Plasmodium species-specific antigen-coated beads in an assay panel could provide a nuanced view of population-level exposure histories, an extensive IgG profile, and detailed seroestimates. A more sensitive serological tool for detection of P. vivax exposure would aid malaria elimination campaigns in co-endemic areas and regions where P. vivax is the dominant parasite.
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Affiliation(s)
- Jessica N McCaffery
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, 954 Gatewood Road, Atlanta, GA, 30329, USA
| | - Balwan Singh
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA
| | - Douglas Nace
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA
| | - Alberto Moreno
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, 954 Gatewood Road, Atlanta, GA, 30329, USA
- Division of Infectious Diseases, Department of Medicine, Emory University, 69 Jesse Hill, Jr. Drive, Atlanta, SEGA, 30303, USA
| | - Venkatachalam Udhayakumar
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA
| | - Eric Rogier
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA.
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De SL, Ntumngia FB, Nicholas J, Adams JH. Progress towards the development of a P. vivax vaccine. Expert Rev Vaccines 2021; 20:97-112. [PMID: 33481638 PMCID: PMC7994195 DOI: 10.1080/14760584.2021.1880898] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 01/21/2021] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Plasmodium vivax causes significant public health problems in endemic regions. A vaccine to prevent disease is critical, considering the rapid spread of drug-resistant parasite strains, and the development of hypnozoites in the liver with potential for relapse. A minimally effective vaccine should prevent disease and transmission while an ideal vaccine provides sterile immunity. AREAS COVERED Despite decades of research, the complex life cycle, technical challenges and a lack of funding have hampered progress of P. vivax vaccine development. Here, we review the progress of potential P. vivax vaccine candidates from different stages of the parasite life cycle. We also highlight the challenges and important strategies for rational vaccine design. These factors can significantly increase immune effector mechanisms and improve the protective efficacy of these candidates in clinical trials to generate sustained protection over longer periods of time. EXPERT OPINION A vaccine that presents functionally-conserved epitopes from multiple antigens from various stages of the parasite life cycle is key to induce broadly neutralizing strain-transcending protective immunity to effectively disrupt parasite development and transmission.
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Affiliation(s)
- Sai Lata De
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa – 33612, FL
| | - Francis B. Ntumngia
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa – 33612, FL
| | - Justin Nicholas
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa – 33612, FL
| | - John H. Adams
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa – 33612, FL
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Asali S, Raz A, Turki H, Mafakher L, Razmjou E, Solaymani-Mohammadi S. Restricted genetic heterogeneity of the Plasmodium vivax transmission-blocking vaccine (TBV) candidate Pvs48/45 in a low transmission setting: Implications for the Plasmodium vivax malaria vaccine development. INFECTION GENETICS AND EVOLUTION 2021; 89:104710. [PMID: 33421653 DOI: 10.1016/j.meegid.2021.104710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 12/28/2020] [Accepted: 01/04/2021] [Indexed: 12/14/2022]
Abstract
Plasmodium vivax is the most widespread malaria species parasitizing humans outside Africa, with approximately 100 million cases reported per year. Most human cases of P. vivax are asymptomatic with low parasitemia, making active case detection-based elimination programme challenging and less effective. Despite the widespread distribution of P. vivax, no effective vaccines are currently available. Transmission blocking vaccines have recently emerged as potential vaccine candidates to reduce transmission rates to below the essential levels required for the maintenance of the parasite life cycle. Here, we demonstrated that P. vivax was the predominant species found in a malaria-endemic area, although P. vivax/P. falciparum co-infections were also common. Through genomic sequence analysis and neighbor-joining algorithms, we demonstrated limited genetic heterogeneity in the P. vivax transmission-blocking vaccine candidate Pvs48/45 among clinical isolates of P. vivax. Restricted genetic polymorphism occurred at both nucleotide and amino acid levels. The most frequent mutation was A → G at nucleotide position 77 (46.7%), whereas the least frequent was C → T at nucleotide position 1230 (3.3%). The occurrence of single nucleotide polymorphisms (SNPs) distribution at 6/8 positions (75%) led to changes in amino acid sequences in the Pvs48/45 loci, whereas 2/8 (25%) of SNPs resulted in no amino acid sequence variations. Consistently, the nucleotide diversity in the Pvs48/45 locus among the P. vivax population studied was extremely low (π = 0.000525). Changes in amino acid sequences in the Pvs48/45 protein did not result in substantial conformational modifications in the tertiary structures of these proteins. Unveiling the population genetic structure and genetic heterogeneity of vaccine target antigens are necessary for rational design of transmission-blocking antibody vaccines and to monitor the vaccine efficacy in clinical trials in endemic areas for malaria.
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Affiliation(s)
- Soheila Asali
- Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Abbasali Raz
- Malaria and Vector Research Group, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Habibollah Turki
- Infectious and Tropical Diseases Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Ladan Mafakher
- Medicinal Plant Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Elham Razmjou
- Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Microbial Biotechnology Research Center (MBiRC), Iran University of Medical Sciences, Tehran, Iran.
| | - Shahram Solaymani-Mohammadi
- Laboratory of Mucosal Immunology, Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, United States.
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Na-Bangchang K, Martviset P, Kitvatanachai S, Tarasuk M, Muhamad P. Pretreatment gametocyte carriage in symptomatic patients with Plasmodium falciparum and Plasmodium vivax infections on the Thai-Myanmar border. J Vector Borne Dis 2021; 58:257-264. [DOI: 10.4103/0972-9062.316274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Bekoe ANA, Allotey EA, Akorsu EE, Abaka-Yawson A, Adusei S, Kpene GE, Kwadzokpui PK. Inter-rater Variability in Malaria Microscopy at the LEKMA Hospital, Ghana. J Parasitol Res 2020; 2020:8897337. [PMID: 33489321 PMCID: PMC7787828 DOI: 10.1155/2020/8897337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 11/09/2020] [Accepted: 11/26/2020] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Malaria remains a major cause of morbidity and mortality worldwide and particularly in sub-Saharan Africa where it is endemic. As such, it is important that a proper diagnosis is made before treatment is initiated. Malaria parasite count plays a key role in the diagnosis and management of malaria. Variations in ratings by laboratory personnel can impact negatively on the treatment regimen for malaria-infected patients. The study is thus aimed at evaluating and comparing the proficiency and parasitaemia counts by two different categories of laboratory staff at the LEKMA Hospital, Ghana. MATERIALS AND METHODS A total of 200 confirmed malaria-positive samples were used in the study. Six thick and thin films were prepared from each sample and uniquely labelled. Two of the six slides were given to two WHO-accredited malaria microscopists to examine and report their respective parasite count/μl (parasite count/WBC × 8000). These were used as the reference for the two categories of laboratory staffs: rater A being diploma holders (Technical Officers referred to as untrained rater) and rater B being degree holders (Medical Laboratory Scientist referred to as trained rater) at the LEKMA Hospital. RESULTS In comparison to the expected outcome, the parasite count by the rater group A (190 (151-239)]) and the rater group B (177 (140-224)) demonstrated significant positive correlation (r = 0.995, p < 0.0001 vs. r = 0.995, p < 0.0001, respectively) with the expected outcome in the cases of heavy parasitaemia. A statistically significant difference (p < 0.05) between counts by the different raters in low parasitemia was observed in this study. A persistent nosedive inter-rater agreement from k = 0.82 to k = 0.40 with increasing density cutoff was observed in this study. CONCLUSION The study observed that the degree of inter-rater agreement of parasite density count by various categories of laboratory personnel is almost perfect. However, the parasite count between raters varied significantly with very low levels of parasitemia but better correlated with heavy parasitemia.
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Affiliation(s)
- Andrew Nii Adzei Bekoe
- Department of Medical Laboratory Sciences, School of Allied Health Sciences, University of Health and Allied Sciences, Ho, Ghana
- Laboratory Department, Ledzokuku Krowor Municipal Assembly (LEKMA) Hospital, Accra, Ghana
| | - Emmanuel Alote Allotey
- Department of Medical Laboratory Sciences, School of Allied Health Sciences, University of Health and Allied Sciences, Ho, Ghana
| | - Elliot Elikplim Akorsu
- Department of Medical Laboratory Sciences, School of Allied Health Sciences, University of Health and Allied Sciences, Ho, Ghana
| | - Albert Abaka-Yawson
- Department of Medical Laboratory Sciences, School of Allied Health Sciences, University of Health and Allied Sciences, Ho, Ghana
| | - Samuel Adusei
- Department of Obstetrics and Gynaecology, University of Cape Town, Cape Town, South Africa
| | - Godsway Edem Kpene
- Department of Medical Laboratory Sciences, School of Allied Health Sciences, University of Health and Allied Sciences, Ho, Ghana
| | - Precious Kwablah Kwadzokpui
- Department of Medical Laboratory Sciences, School of Allied Health Sciences, University of Health and Allied Sciences, Ho, Ghana
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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 PMCID: PMC7646789 DOI: 10.4269/ajtmh.20-0485] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 06/26/2020] [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.
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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
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Ashley EA, Poespoprodjo JR. Treatment and prevention of malaria in children. THE LANCET CHILD & ADOLESCENT HEALTH 2020; 4:775-789. [PMID: 32946831 DOI: 10.1016/s2352-4642(20)30127-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 03/11/2020] [Accepted: 03/25/2020] [Indexed: 10/23/2022]
Abstract
Malaria disproportionately affects children younger than 5 years. Falciparum malaria is responsible for more than 200 000 child deaths per year in Africa and vivax malaria is well documented as a cause of severe anaemia and excess mortality in children in Asia and Oceania. For the treatment of malaria in children, paediatric dosing recommendations for several agents, including parenteral artesunate and dihydroartemisinin-piperaquine, have belatedly been shown to be suboptimal. Worsening antimalarial resistance in Plasmodium falciparum in the Greater Mekong Subregion threatens to undermine global efforts to control malaria. Triple antimalarial combination therapies are being evaluated to try to impede this threat. The RTS,S/AS01 vaccine gives partial protection against falciparum malaria and is being evaluated in large, pilot studies in Ghana, Malawi, and Kenya as a complementary tool to other preventive measures. Seasonal malaria chemoprevention in west Africa has resulted in declines in malaria incidence and deaths and there is interest in scaling up efforts by expanding the age range of eligible recipients. Preventing relapse in Plasmodium vivax infection with primaquine is challenging because treating children who have G6PD deficiency with primaquine can cause acute haemolytic anaemia. The safety of escalating dose regimens for primaquine is being studied to mitigate this risk.
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Affiliation(s)
- Elizabeth A Ashley
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Vientiane, Laos; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| | - Jeanne Rini Poespoprodjo
- Timika Research Facility, Papuan Health and Community Development Foundation, Timika, Indonesia; Department of Child Health, Faculty of Medicine, Public Health and Nursing, Gadjah Mada University, Yogyakarta, Indonesia
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Ortega MÁ, Guzmán Merino A, Fraile-Martínez O, Recio-Ruiz J, Pekarek L, G. Guijarro L, García-Honduvilla N, Álvarez-Mon M, Buján J, García-Gallego S. Dendrimers and Dendritic Materials: From Laboratory to Medical Practice in Infectious Diseases. Pharmaceutics 2020; 12:pharmaceutics12090874. [PMID: 32937793 PMCID: PMC7560085 DOI: 10.3390/pharmaceutics12090874] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 09/11/2020] [Accepted: 09/11/2020] [Indexed: 02/07/2023] Open
Abstract
Infectious diseases are one of the main global public health risks, predominantly caused by viruses, bacteria, fungi, and parasites. The control of infections is founded on three main pillars: prevention, treatment, and diagnosis. However, the appearance of microbial resistance has challenged traditional strategies and demands new approaches. Dendrimers are a type of polymeric nanoparticles whose nanometric size, multivalency, biocompatibility, and structural perfection offer boundless possibilities in multiple biomedical applications. This review provides the reader a general overview about the uses of dendrimers and dendritic materials in the treatment, prevention, and diagnosis of highly prevalent infectious diseases, and their advantages compared to traditional approaches. Examples of dendrimers as antimicrobial agents per se, as nanocarriers of antimicrobial drugs, as well as their uses in gene transfection, in vaccines or as contrast agents in imaging assays are presented. Despite the need to address some challenges in order to be used in the clinic, dendritic materials appear as an innovative tool with a brilliant future ahead in the clinical management of infectious diseases and many other health issues.
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Affiliation(s)
- Miguel Ángel Ortega
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcalá de Henares, Spain; (M.Á.O.); (A.G.M.); (O.F.-M.); (L.P.); (N.G.-H.); (M.Á.-M.); (J.B.)
- Institute Ramón y Cajal for Health Research (IRYCIS), 28034 Madrid, Spain
- Tumour Registry, Pathological Anatomy Service, University Hospital Príncipe de Asturias, 28805 Alcalá de Henares, Spain
- University Center for the Defense of Madrid (CUD-ACD), 28047 Madrid, Spain
| | - Alberto Guzmán Merino
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcalá de Henares, Spain; (M.Á.O.); (A.G.M.); (O.F.-M.); (L.P.); (N.G.-H.); (M.Á.-M.); (J.B.)
| | - Oscar Fraile-Martínez
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcalá de Henares, Spain; (M.Á.O.); (A.G.M.); (O.F.-M.); (L.P.); (N.G.-H.); (M.Á.-M.); (J.B.)
| | - Judith Recio-Ruiz
- Department of Organic and Inorganic Chemistry, Faculty of Sciences, and Research Institute in Chemistry “Andrés M. del Río” (IQAR), University of Alcalá, 28801 Alcalá de Henares, Spain;
| | - Leonel Pekarek
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcalá de Henares, Spain; (M.Á.O.); (A.G.M.); (O.F.-M.); (L.P.); (N.G.-H.); (M.Á.-M.); (J.B.)
| | - Luis G. Guijarro
- Department of Systems Biology, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcalá de Henares, Spain;
- Networking Research Centre on Hepatic and Digestive Diseases (CIBER-EHD), 28029 Madrid, Spain
| | - Natalio García-Honduvilla
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcalá de Henares, Spain; (M.Á.O.); (A.G.M.); (O.F.-M.); (L.P.); (N.G.-H.); (M.Á.-M.); (J.B.)
- Institute Ramón y Cajal for Health Research (IRYCIS), 28034 Madrid, Spain
- University Center for the Defense of Madrid (CUD-ACD), 28047 Madrid, Spain
| | - Melchor Álvarez-Mon
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcalá de Henares, Spain; (M.Á.O.); (A.G.M.); (O.F.-M.); (L.P.); (N.G.-H.); (M.Á.-M.); (J.B.)
- Institute Ramón y Cajal for Health Research (IRYCIS), 28034 Madrid, Spain
- University Center for the Defense of Madrid (CUD-ACD), 28047 Madrid, Spain
- Immune System Diseases-Rheumatology, Oncology and Medicine Service, University Hospital Príncipe de Asturias, 28805 Alcalá de Henares, Madrid, Spain
| | - Julia Buján
- Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, 28801 Alcalá de Henares, Spain; (M.Á.O.); (A.G.M.); (O.F.-M.); (L.P.); (N.G.-H.); (M.Á.-M.); (J.B.)
- Institute Ramón y Cajal for Health Research (IRYCIS), 28034 Madrid, Spain
- Tumour Registry, Pathological Anatomy Service, University Hospital Príncipe de Asturias, 28805 Alcalá de Henares, Spain
- University Center for the Defense of Madrid (CUD-ACD), 28047 Madrid, Spain
| | - Sandra García-Gallego
- Institute Ramón y Cajal for Health Research (IRYCIS), 28034 Madrid, Spain
- Department of Organic and Inorganic Chemistry, Faculty of Sciences, and Research Institute in Chemistry “Andrés M. del Río” (IQAR), University of Alcalá, 28801 Alcalá de Henares, Spain;
- Correspondence:
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Wardhani P, Butarbutar TV, Adiatmaja CO, Betaubun AM, Hamidah N, Aryati. Performance comparison of two malaria rapid diagnostic test with real time polymerase chain reaction and gold standard of microscopy detection method. Infect Dis Rep 2020; 12:8731. [PMID: 32874462 PMCID: PMC7447940 DOI: 10.4081/idr.2020.8731] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 07/01/2020] [Indexed: 11/23/2022] Open
Abstract
Background The diagnostic test for malaria is mostly based on Rapid Diagnostic Test (RDT) and detection by microscopy. Polymerase Chain Reaction (PCR) is also a sensitive detection method that can be considered as a diagnostic tool. The outcome of malaria microscopy detection depends on the examiner's ability and experience. Some RDT has been distributed in Indonesia, which needs to be evaluated for their results. Objective This study aimed to compare the performance of RightSign RDT and ScreenPlus RDT for detection of Plasmodium in human blood. We used specific real-time polymerase chain reaction abTESTMMalaria qPCRII) and gold standard of microscopy detection method to measure diagnostic efficiency. Methods Blood specimens were evaluated using RightSign RDT, ScreenPlus RDT, Microscopy detection, and RT-PCR as the protocol described. The differences on specificity (Sp), sensitivity (Sn), positive predictive value (PPV), and negative predictive value (NPV) were analyzed using McNemar and Kruskal Wallis analysis. Results A total of 105 subjects were recruited. Based on microscopy test, RightSign RDT had sensitivity, Specificity, PPV, NPV, 100%, 98%, 98.2%, 100%, respectively. ScreenPlus showed 100% sensitivity, 98% specificity, 98.2% PPV, 100% NPV. The sensitivity of both RDTs became lower (75%) and the specificity higher (100 %) when using real-time PCR. Both RDTs showed a 100% agreement. RTPCR detected higher mix infection when compared to microscopy and RDTs. Conclusion RightSign and ScreenPlus RDT have excellent performance when using microscopy detection as a gold standard. Real-time PCR method can be considered as a confirmation tool for malaria diagnosis.
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Affiliation(s)
- Puspa Wardhani
- Clinical Pathology Department.,Dr. Soetomo General Academic Hospital, Surabaya, Indonesia
| | - Trieva Verawaty Butarbutar
- Clinical Pathology Specialist Study Programme, Clinical Pathology Department.,Dr. Soetomo General Academic Hospital, Surabaya, Indonesia
| | - Christophorus Oetama Adiatmaja
- Clinical Pathology Specialist Study Programme, Clinical Pathology Department.,Dr. Soetomo General Academic Hospital, Surabaya, Indonesia
| | - Amarensi Milka Betaubun
- Clinical Pathology Subspecialist Study Programme, Clinical Pathology Department, Faculty of Medicine.,Dr. Soetomo General Academic Hospital, Surabaya, Indonesia
| | - Nur Hamidah
- Science and Technology Faculty, C Campus, Universitas Airlangga
| | - Aryati
- Clinical Pathology Department.,Dr. Soetomo General Academic Hospital, Surabaya, Indonesia
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The Importance of an Active Case Detection (ACD) Programme for Malaria among Migrants from Malaria Endemic Countries: The Greek Experience in a Receptive and Vulnerable Area. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17114080. [PMID: 32521653 PMCID: PMC7312366 DOI: 10.3390/ijerph17114080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/26/2020] [Accepted: 06/04/2020] [Indexed: 11/23/2022]
Abstract
Greece has been malaria-free since 1974. In October 2011, following an outbreak of 36 locally acquired malaria (LAM) cases in Evrotas Municipality, a Pro-Active Case Detection (PACD) program for malaria was implemented among migrants from malaria-endemic countries, to support early diagnosis and treatment of cases. We evaluated the PACD program for the years 2012–2017 using indicators such as the number of locally acquired cases, the detection rate/sensitivity and the timeliness of diagnosis and treatment. We visited each migrant home every 7–15 days to screen migrants for malaria symptoms, performing Rapid Diagnostic Tests (RDTs) and blood smears on symptomatic patients. We estimated: (i) the number of malaria cases detected by the PACD, divided by the total number of reported malaria cases during the same period among the same population; (ii) the time between onset of symptoms, diagnosis and initiation of treatment. The total number of migrants who were screened for malaria symptoms for the years 2012–2017 was 5057 with 84,169 fever screenings conducted, while 2288 RDTs and 1736 blood smears were performed. During the same period, 53 imported P. vivax malaria cases were detected, while incidence of malaria among migrants was estimated at 1.8% annually. Ten and one LAM cases were also reported in 2012 and 2015, respectively. Sensitivity of PACD ranged from 86% to 100%; median timeliness between onset of symptoms and diagnosis decreased from 72 h in 2012 to 12 h in 2017 (83% decrease), while timeliness between diagnosis and treatment initiation was 0 h. The implementation of PACD could be considered an effective prevention and response tool against malaria re-introduction.
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Ayala MJC, Villela DAM. Early transmission of sensitive strain slows down emergence of drug resistance in Plasmodium vivax. PLoS Comput Biol 2020; 16:e1007945. [PMID: 32555701 PMCID: PMC7363008 DOI: 10.1371/journal.pcbi.1007945] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 06/29/2020] [Accepted: 05/13/2020] [Indexed: 11/19/2022] Open
Abstract
The spread of drug resistance of Plasmodium falciparum and Plasmodium vivax parasites is a challenge towards malaria elimination. P. falciparum has shown an early and severe drug resistance in comparison to P. vivax in various countries. In fact, P. vivax differs in its life cycle and treatment in various factors: development and duration of sexual parasite forms differ, symptoms severity are unequal, relapses present only in P. vivax cases and the Artemisinin-based combination therapy (ACT) is only mandatory in P. falciparum cases. We compared the spread of drug resistance for both species through two compartmental models using ordinary differential equations. The model structure describes how sensitive and resistant parasite strains infect a human population treated with antimalarials. We found that an early transmission,i.e., before treatment and low effectiveness of drug coverage, supports the prevalence of sensitive parasites delaying the emergence of resistant P. vivax. These results imply that earlier attention of both symptomatic cases and reservoirs of P. vivax are essential in controlling transmission but also accelerate the spread of drug resistance.
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Affiliation(s)
- Mario J. C. Ayala
- Programa de Computação Científica, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Daniel A. M. Villela
- Programa de Computação Científica, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
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Longley RJ, White MT, Takashima E, Brewster J, Morita M, Harbers M, Obadia T, Robinson LJ, Matsuura F, Liu ZSJ, Li-Wai-Suen CSN, Tham WH, Healer J, Huon C, Chitnis CE, Nguitragool W, Monteiro W, Proietti C, Doolan DL, Siqueira AM, Ding XC, Gonzalez IJ, Kazura J, Lacerda M, Sattabongkot J, Tsuboi T, Mueller I. Development and validation of serological markers for detecting recent Plasmodium vivax infection. Nat Med 2020; 26:741-749. [DOI: 10.1038/s41591-020-0841-4] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 03/18/2020] [Indexed: 11/09/2022]
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Mosnier E, Roux E, Cropet C, Lazrek Y, Moriceau O, Gaillet M, Mathieu L, Nacher M, Demar M, Odonne G, Douine M, Michaud C, Pelleau S, Djossou F, Musset L. Prevalence of Plasmodium spp. in the Amazonian Border Context (French Guiana-Brazil): Associated Factors and Spatial Distribution. Am J Trop Med Hyg 2020; 102:130-141. [PMID: 31769403 PMCID: PMC6947805 DOI: 10.4269/ajtmh.19-0378] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
To implement future malaria elimination strategies in French Guiana, a characterization of the infectious reservoir is recommended. A cross-sectional survey was conducted between October and December 2017 in the French Guianese municipality of St Georges de l'Oyapock, located along the Brazilian border. The prevalence of Plasmodium spp. was determined using a rapid diagnostic test (RDT) and a polymerase chain reaction (PCR). Demographic, house locations, medical history, and biological data were analyzed. Factors associated with Plasmodium spp. carriage were analyzed using logistic regression, and the carriage localization was investigated through spatial cluster analysis. Of the 1,501 samples analyzed with PCR, positive results totaled 90 and 10 for Plasmodium vivax and Plasmodium falciparum, respectively. The general PCR prevalence was 6.6% [5.3-7.9], among which 74% were asymptomatic. Only 13/1,549 were positive by RDT. In multivariate analysis, participants older than 15 years, living in a remote neighborhood, with a prior history of malaria, anemia, and thrombocytopenia were associated with an increased odds of Plasmodium spp. carriage. High-risk clusters of P. vivax carriage were detected in the most remote neighborhoods on the village outskirts and two small foci in the village center. We also detected a hot spot for both P. vivax and P. falciparum symptomatic carriers in the northwestern part of the village. The present study confirms a wide-scale presence of asymptomatic P. falciparum and P. vivax carriers in this area. Although they were more often located in remote areas, their geographic distribution was spatially heterogeneous and complex.
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Affiliation(s)
- Emilie Mosnier
- Ecosystèmes Amazoniens et Pathologie Tropicale, EA3593, Université de Guyane, Cayenne, France.,Pôle des Centres Délocalisés de Prévention et de Soins, Centre Hospitalier Andrée Rosemon, Cayenne, France
| | - Emmanuel Roux
- LIS, ICICT, Fiocruz, Rio de Janeiro, Brazil.,ESPACE-DEV, IRD, Université de Montpellier, Université de La Réunion, Université de Guyane, Université des Antilles, Montpellier, France
| | - Claire Cropet
- Centre d'Investigation Clinique Antilles Guyane-Inserm 1424, Cayenne, France
| | - Yassamine Lazrek
- Laboratoire de Parasitologie, Centre National de Référence du Paludisme, Pôle Zones Endémiques, WHO Collaborating Center for Surveillance of Antimalarial Drug Resistance, Institut Pasteur de la Guyane, Cayenne, France
| | - Olivier Moriceau
- Laboratoire de Parasitologie, Centre National de Référence du Paludisme, Pôle Zones Endémiques, WHO Collaborating Center for Surveillance of Antimalarial Drug Resistance, Institut Pasteur de la Guyane, Cayenne, France
| | - Mélanie Gaillet
- Pôle des Centres Délocalisés de Prévention et de Soins, Centre Hospitalier Andrée Rosemon, Cayenne, France
| | - Luana Mathieu
- Laboratoire de Parasitologie, Centre National de Référence du Paludisme, Pôle Zones Endémiques, WHO Collaborating Center for Surveillance of Antimalarial Drug Resistance, Institut Pasteur de la Guyane, Cayenne, France
| | - Mathieu Nacher
- Centre d'Investigation Clinique Antilles Guyane-Inserm 1424, Cayenne, France
| | - Magalie Demar
- Laboratoire de Parasitologie et Mycologie, Centre Hospitalier Andrée Rosemon, Cayenne, France
| | - Guillaume Odonne
- UMSR Laboratoire Ecologie, Evolution, Interactions des Systèmes Amazoniens Laboratoire Ecologie, Evolution, Interactions des Systèmes Amazoniens (LEESIA), Centre National de la Recherche Scientifique (CNRS), Cayenne, France
| | - Maylis Douine
- Centre d'Investigation Clinique Antilles Guyane-Inserm 1424, Cayenne, France.,Ecosystèmes Amazoniens et Pathologie Tropicale, EA3593, Université de Guyane, Cayenne, France
| | - Céline Michaud
- Pôle des Centres Délocalisés de Prévention et de Soins, Centre Hospitalier Andrée Rosemon, Cayenne, France
| | - Stéphane Pelleau
- Laboratoire de Parasitologie, Centre National de Référence du Paludisme, Pôle Zones Endémiques, WHO Collaborating Center for Surveillance of Antimalarial Drug Resistance, Institut Pasteur de la Guyane, Cayenne, France
| | - Félix Djossou
- Unité de Maladies Infectieuses et Tropicales, Centre Hospitalier Andrée Rosemon, Cayenne, France
| | - Lise Musset
- Laboratoire de Parasitologie, Centre National de Référence du Paludisme, Pôle Zones Endémiques, WHO Collaborating Center for Surveillance of Antimalarial Drug Resistance, Institut Pasteur de la Guyane, Cayenne, France
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Tilahun A, Yimer M, Gelaye W, Tegegne B. Prevalence of asymptomatic Plasmodium species infection and associated factors among pregnant women attending antenatal care at Fendeka town health facilities, Jawi District, North west Ethiopia: A cross-sectional study. PLoS One 2020; 15:e0231477. [PMID: 32315341 PMCID: PMC7173768 DOI: 10.1371/journal.pone.0231477] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 03/24/2020] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Malaria in pregnancy remains a major public health problem especially in sub-Saharan Africa. In malaria endemic areas, majority of pregnant women may remain asymptomatic but still associated with complications on the mother and her foetus. They also serve as reservoirs and act as transmitters of infection. Despite these effects, the prevalence of asymptomatic Plasmodium species infections among pregnant women attending antenatal care has not been yet studied at the study area. Therefore, the aim of this study was to assess the prevalence of asymptomatic Plasmodium species infections among pregnant women attending antenatal care at Fendeka town health facilities. METHODS Health facility based cross -sectional study was conducted from February to March 2019. A total of 331 participants were enrolled by using convenient sampling technique. Socio-demographic and associated factors were collected by a face to face interview. All the 331 samples were tested using rapid diagnostic tests (RDTs) and microscopy. However, only 83 dried blood spot (DBS) samples out of 331 participants, were collected by using systematic random sampling technique for molecular analysis. Data was analysed using SPSS version 20. Descriptive statistics were used to determine the prevalence of asymptomatic Plasmodium species infections. Univariate logistic regression was employed to assess factors associated with asymptomatic Plasmodium species infection. Variables with P-value < 0.25 in the univariate logistic regression were selected for multivariate logistic regression analysis model. Odds ratios with 95% confidence intervals were calculated and P- values < 0.05 were considered as statistically significant. RESULTS Overall, 37 (11.2%) asymptomatic Plasmodium species infections were detected using: RDTs, microscopy and real-time PCR altogether. The asymptomatic Plasmodium species infection prevalence was 17 (5.1%), 30 (9.1%) and 15(18.1%) using RDTs, microscopy and real-time PCR, respectively. Asymptomatic Plasmodium species infections were more likely to occur in primigravida (AOR: 4.51, 95% CI: 1.27-16.03), secundigravida (AOR: 3.87, 95% CI: 1.16-12.93), rural inhabitants (AOR: 4.51, 95% CI: 1.72-11.84) and in participants who did not use indoor residual spray (IRS) for the last one year (AOR: 3.13, 95% CI: 1.47-6.66). CONCLUSIONS The prevalence of asymptomatic Plasmodium species infection was 11.2%. Pregnant women who reside in the rural area, primigravidae, secugravidae and those who did not utilize indoor residual spray for the last one year were at high risk of infection. Therefore, routine laboratory diagnosis of asymptomatic Plasmodium species infection among pregnant women should be adopted as a part of the antenatal care.
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Affiliation(s)
- Adane Tilahun
- Debre-Markos Referral Hospital, Medical Laboratory Service, Debre-Markos, Ethiopia
| | - Mulat Yimer
- Department of Medical Laboratory Sciences, School of Health Sciences, College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia
| | - Woynshet Gelaye
- Department of Medical Laboratory Sciences, School of Health Sciences, College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia
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Novel Insights into Plasmodium vivax Therapeutic Failure: CYP2D6 Activity and Time of Exposure to Malaria Modulate the Risk of Recurrence. Antimicrob Agents Chemother 2020; 64:AAC.02056-19. [PMID: 32122891 DOI: 10.1128/aac.02056-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 02/24/2020] [Indexed: 12/21/2022] Open
Abstract
Plasmodium vivax relapse is one of the major causes of sustained global malaria transmission. Primaquine (PQ) is the only commercial drug available to prevent relapses, and its efficacy is dependent on metabolic activation by cytochrome P450 2D6 (CYP2D6). Impaired CYP2D6 function, caused by allelic polymorphisms, leads to the therapeutic failure of PQ as a radical cure for P. vivax malaria. Here, we hypothesized that the host immune response to malaria parasites modulates susceptibility to P. vivax recurrences in association with CYP2D6 activity. We performed a 10-year retrospective study by genotyping CYP2D6 polymorphisms in 261 malaria-exposed individuals from the Brazilian Amazon. The immune responses against a panel of P. vivax blood-stage antigens were evaluated by serological assays. We confirmed our previous findings, which indicated an association between impaired CYP2D6 activity and a higher risk of multiple episodes of P. vivax recurrence (risk ratio, 1.75; 95% confidence interval [CI], 1.2 to 2.6; P = 0.0035). An important finding was a reduction of 3% in the risk of recurrence (risk ratio, 0.97; 95% CI, 0.96 to 0.98; P < 0.0001) per year of malaria exposure, which was observed for individuals with both reduced and normal CYP2D6 activity. Accordingly, subjects with long-term malaria exposure and persistent antibody responses to various antigens showed fewer episodes of malaria recurrence. Our findings have direct implications for malaria control, since it was shown that nonimmune individuals who do not respond adequately to treatment due to reduced CYP2D6 activity may present a significant challenge for sustainable progress toward P. vivax malaria elimination.
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