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Azizi H, Majdzadeh R, Ahmadi A, Raeisi A, Nazemipour M, Mansournia MA, Schapira A. Development and validation of an online tool for assessment of health care providers' management of suspected malaria in an area, where transmission has been interrupted. Malar J 2022; 21:304. [PMID: 36303211 DOI: 10.1186/s12936-022-04308-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Accepted: 09/30/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The alertness and practice of health care providers (HCPs) in the correct management of suspected malaria (CMSM) (vigilance) is a central component of malaria surveillance following elimination, and it must be established before malaria elimination certification can be granted. This study was designed to develop and validate a rapid tool, Simulated Malaria Online Tool (SMOT), to evaluate HCPs' practice in relation to the CMSM. METHODS The study was conducted in East Azerbaijan Province, Islamic Republic of Iran, where no malaria transmission has been reported since 2005. An online tool presenting a suspected malaria case for detection of HCPs' failures in recognition, diagnosis, treatment and reporting was developed based on literature review and expert opinion. A total of 360 HCPs were allocated to two groups. In one group their performance was tested by simulated patient (SP) methodology as gold standard, and one month later by the online tool to allow assessment of its sensitivity. In the other group, they were tested only by the online tool to allow assessment of any possible bias incurred by the exposure to SPs before the tool. RESULTS The sensitivity of the tool was (98.7%; CI 93.6-99.3). The overall agreement and kappa statistics were 96.6% and 85.6%, respectively. In the group tested by both methods, the failure proportion by SP was 86.1% (CI 80.1-90.8) and by tool 87.2% (CI 81.4-91.7). In the other group, the tool found 85.6% (CI 79.5-90.3) failures. There were no significant differences in detecting failures within or between the groups. CONCLUSION The SMOT tool not only showed high validity for detecting HCPs' failures in relation to CMSM, but it had high rates of agreement with the real-world situation, where malaria transmission has been interrupted. The tool can be used by program managers to evaluate HCPs' performance and identify sub-groups, whose malaria vigilance should be strengthened. It could also contribute to the evidence base for certification of malaria elimination, and to strengthening prevention of re-establishment of malaria transmission.
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Affiliation(s)
- Hosein Azizi
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.,Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Majdzadeh
- School of Health and Social Care, University of Essex, Colchester, UK.,School of Public Health, Knowledge Utilization Research Center, and Community Based Participatory Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Ayat Ahmadi
- Knowledge Utilization Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Raeisi
- National Programme Manager for Malaria Elimination, Department of Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Nazemipour
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Ali Mansournia
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
| | - Allan Schapira
- Bicol University College of Medicine, Legazpi City, Philippines
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2
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Mathews ES, Jezewski AJ, Odom John AR. Protein Prenylation and Hsp40 in Thermotolerance of Plasmodium falciparum Malaria Parasites. mBio 2021; 12:e0076021. [PMID: 34182772 PMCID: PMC8262983 DOI: 10.1128/mbio.00760-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 06/01/2021] [Indexed: 12/31/2022] Open
Abstract
During its complex life cycle, the malaria parasite survives dramatic environmental stresses, including large temperature shifts. Protein prenylation is required during asexual replication of Plasmodium falciparum, and the canonical heat shock protein 40 protein (HSP40; PF3D7_1437900) is posttranslationally modified with a 15-carbon farnesyl isoprenyl group. In other organisms, farnesylation of Hsp40 orthologs controls their localization and function in resisting environmental stress. In this work, we find that plastidial isopentenyl pyrophosphate (IPP) synthesis and protein farnesylation are required for malaria parasite survival after cold and heat shock. Furthermore, loss of HSP40 farnesylation alters its membrane attachment and interaction with proteins in essential pathways in the parasite. Together, this work reveals that farnesylation is essential for parasite survival during temperature stress. Farnesylation of HSP40 may promote thermotolerance by guiding distinct chaperone-client protein interactions.
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Affiliation(s)
- Emily S. Mathews
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Andrew J. Jezewski
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Audrey R. Odom John
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
- Division of Infectious Disease, Department of Pediatrics, Children’s Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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3
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Thwing J, Camara A, Candrinho B, Zulliger R, Colborn J, Painter J, Plucinski MM. A Robust Estimator of Malaria Incidence from Routine Health Facility Data. Am J Trop Med Hyg 2020; 102:811-820. [PMID: 31833469 DOI: 10.4269/ajtmh.19-0600] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Routine incident malaria case data have become a pillar of malaria surveillance in sub-Saharan Africa. These data provide granular, timely information to track malaria burden. However, incidence data are sensitive to changes in care seeking rates, rates of testing of suspect cases, and reporting completeness. Based on a set of assumptions, we derived a simple algebraic formula to convert crude incidence rates to a corrected estimation of incidence, adjusting for biases in variable and suboptimal rates of care seeking, testing of suspect cases, and reporting completeness. We applied the correction to routine incidence data from Guinea and Mozambique, and aggregate data for sub-Saharan African countries from the World Malaria Report. We calculated continent-wide needs for malaria tests and treatments, assuming universal testing but current care seeking rates. Countries in southern and eastern Africa reporting recent increases in malaria incidence generally had lower overall corrected incidence than countries in Central and West Africa. Under current care seeking rates, the unmet need for malaria tests was estimated to be 160 million (M) (interquartile range [IQR]: 139-188) and for malaria treatments to be 37 M (IQR: 29-51). Maps of corrected incidence were more consistent with maps of community survey prevalence than was crude incidence in Guinea and Mozambique. Crude malaria incidence rates need to be interpreted in the context of suboptimal testing and care seeking rates, which vary over space and time. Adjusting for these factors can provide insight into the spatiotemporal trends of malaria burden.
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Affiliation(s)
- Julie Thwing
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Alioune Camara
- National Malaria Control Program, Ministry of Health, Conakry, Guinea
| | - Baltazar Candrinho
- National Malaria Control Program, Ministry of Health, Maputo, Mozambique
| | - Rose Zulliger
- U.S. President's Malaria Initiative, Centers for Disease Control and Prevention, Maputo, Mozambique.,Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - James Colborn
- Clinton Health Access Initiative, Maputo, Mozambique
| | - John Painter
- U.S. President's Malaria Initiative, Centers for Disease Control and Prevention, Atlanta, Georgia.,Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Mateusz M Plucinski
- U.S. President's Malaria Initiative, Centers for Disease Control and Prevention, Atlanta, Georgia.,Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
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4
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Hemben A, Ashley J, Tothill IE. An immunosensor for parasite lactate dehydrogenase detection as a malaria biomarker – Comparison with commercial test kit. Talanta 2018; 187:321-329. [DOI: 10.1016/j.talanta.2018.04.086] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/24/2018] [Accepted: 04/26/2018] [Indexed: 11/25/2022]
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5
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Plucinski MM, Guilavogui T, Camara A, Ndiop M, Cisse M, Painter J, Thwing J. How Far Are We from Reaching Universal Malaria Testing of All Fever Cases? Am J Trop Med Hyg 2018; 99:670-679. [PMID: 29943717 DOI: 10.4269/ajtmh.18-0312] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Universal malaria diagnostic testing of all fever cases is the first step in correct malaria case management. However, monitoring adherence to universal testing is complicated by unreliable recording and reporting of the true number of fever cases. We searched the literature to obtain gold-standard estimates for the proportion of patients attending outpatient clinics in sub-Saharan Africa with malarial and non-malarial febrile illness. To correct for differences in malaria transmission, we calculated the proportion of patients with fever after excluding confirmed malaria cases. Next, we analyzed routine data from Guinea and Senegal to calculate the proportion of outpatients tested after exclusion of confirmed malaria cases from the numerator and denominator. From 12 health facility surveys in sub-Saharan Africa with gold-standard fever screening, the median proportion of febrile illness among outpatients after exclusion of confirmed malaria fevers was 57% (range: 46-80%). Analysis of routine data after exclusion of confirmed malaria cases demonstrated much lower testing proportions of 23% (Guinea) and 13% (Senegal). There was substantial spatial and temporal heterogeneity in this testing proportion, and testing in Senegal was correlated with malaria season. Given the evidence from gold-standard surveys that at least 50% of non-malaria consultations in sub-Saharan Africa are for febrile illness, it appears that a substantial proportion of patients with fever are not tested for malaria in health facilities when considering routine data. Tracking the proportion of patients tested for malaria after exclusion of the confirmed malaria cases could allow programs to make inferences about malaria testing practices using routine data.
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Affiliation(s)
- Mateusz M Plucinski
- President's Malaria Initiative, Centers for Disease Control and Prevention, Atlanta, Georgia.,Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | | | - Alioune Camara
- National Malaria Control Program, Ministry of Health, Conakry, Guinea
| | - Médoune Ndiop
- National Malaria Control Program, Ministry of Health, Dakar, Senegal
| | - Moustapha Cisse
- National Malaria Control Program, Ministry of Health, Dakar, Senegal
| | - John Painter
- President's Malaria Initiative, Centers for Disease Control and Prevention, Atlanta, Georgia.,Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Julie Thwing
- Malaria Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
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6
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Development of an Immunosensor for PfHRP 2 as a Biomarker for Malaria Detection. BIOSENSORS-BASEL 2017; 7:bios7030028. [PMID: 28718841 PMCID: PMC5618034 DOI: 10.3390/bios7030028] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 07/10/2017] [Accepted: 07/12/2017] [Indexed: 11/17/2022]
Abstract
Plasmodium falciparum histidine-rich protein 2 (PfHRP 2) was selected in this work as the biomarker for the detection and diagnosis of malaria. An enzyme-linked immunosorbent assay (ELISA) was first developed to evaluate the immunoreagent’s suitability for the sensor’s development. A gold-based sensor with an integrated counter and an Ag/AgCl reference electrode was first selected and characterised and then used to develop the immunosensor for PfHRP 2, which enables a low cost, easy to use, and sensitive biosensor for malaria diagnosis. The sensor was applied to immobilise the anti-PfHRP 2 monoclonal antibody as the capture receptor. A sandwich ELISA assay format was constructed using horseradish peroxidase (HRP) as the enzyme label, and the electrochemical signal was generated using a 3, 3′, 5, 5′tetramethyl-benzidine dihydrochloride (TMB)/H2O2 system. The performance of the assay and the sensor were optimised and characterised, achieving a PfHRP 2 limit of detection (LOD) of 2.14 ng·mL−1 in buffer samples and 2.95 ng∙mL−1 in 100% spiked serum samples. The assay signal was then amplified using gold nanoparticles conjugated detection antibody-enzyme and a detection limit of 36 pg∙mL−1 was achieved in buffer samples and 40 pg∙mL−1 in serum samples. This sensor format is ideal for malaria detection and on-site analysis as a point-of-care device (POC) in resource-limited settings where the implementation of malaria diagnostics is essential in control and elimination efforts.
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7
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De Santis O, Kilowoko M, Kyungu E, Sangu W, Cherpillod P, Kaiser L, Genton B, D’Acremont V. Predictive value of clinical and laboratory features for the main febrile diseases in children living in Tanzania: A prospective observational study. PLoS One 2017; 12:e0173314. [PMID: 28464021 PMCID: PMC5413055 DOI: 10.1371/journal.pone.0173314] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 02/17/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND To construct evidence-based guidelines for management of febrile illness, it is essential to identify clinical predictors for the main causes of fever, either to diagnose the disease when no laboratory test is available or to better target testing when a test is available. The objective was to investigate clinical predictors of several diseases in a cohort of febrile children attending outpatient clinics in Tanzania, whose diagnoses have been established after extensive clinical and laboratory workup. METHOD From April to December 2008, 1005 consecutive children aged 2 months to 10 years with temperature ≥38°C attending two outpatient clinics in Dar es Salaam were included. Demographic characteristics, symptoms and signs, comorbidities, full blood count and liver enzyme level were investigated by bi- and multi-variate analyses (Chan, et al., 2008). To evaluate accuracy of combined predictors to construct algorithms, classification and regression tree (CART) analyses were also performed. RESULTS 62 variables were studied. Between 4 and 15 significant predictors to rule in (aLR+>1) or rule out (aLR+<1) the disease were found in the multivariate analysis for the 7 more frequent outcomes. For malaria, the strongest predictor was temperature ≥40°C (aLR+8.4, 95%CI 4.7-15), for typhoid abdominal tenderness (5.9,2.5-11), for urinary tract infection (UTI) age ≥3 years (0.20,0-0.50), for radiological pneumonia abnormal chest auscultation (4.3,2.8-6.1), for acute HHV6 infection dehydration (0.18,0-0.75), for bacterial disease (any type) chest indrawing (19,8.2-60) and for viral disease (any type) jaundice (0.28,0.16-0.41). Other clinically relevant and easy to assess predictors were also found: malaria could be ruled in by recent travel, typhoid by jaundice, radiological pneumonia by very fast breathing and UTI by fever duration of ≥4 days. The CART model for malaria included temperature, travel, jaundice and hepatomegaly (sensitivity 80%, specificity 64%); typhoid: age ≥2 years, jaundice, abdominal tenderness and adenopathy (46%,93%); UTI: age <2 years, temperature ≥40°C, low weight and pale nails (20%,96%); radiological pneumonia: very fast breathing, chest indrawing and leukocytosis (38%,97%); acute HHV6 infection: less than 2 years old, (no) dehydration, (no) jaundice and (no) rash (86%,51%); bacterial disease: chest indrawing, chronic condition, temperature ≥39.7°c and fever duration >3 days (45%,83%); viral disease: runny nose, cough and age <2 years (68%,76%). CONCLUSION A better understanding of the relative performance of these predictors might be of great help for clinicians to be able to better decide when to test, treat, refer or simply observe a sick child, in order to decrease morbidity and mortality, but also to avoid unnecessary antimicrobial prescription. These predictors have been used to construct a new algorithm for the management of childhood illnesses called ALMANACH.
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Affiliation(s)
- Olga De Santis
- Department of Ambulatory Care and Community Medicine, University of Lausanne, Lausanne, Switzerland
- University of Barcelona, Barcelona, Spain
| | - Mary Kilowoko
- Amana Hospital, Dar es Salaam, United Republic of Tanzania
| | - Esther Kyungu
- St-Francis Hospital, Ifakara, United Republic of Tanzania
| | - Willy Sangu
- Ilala Municipal Council, Dar es Salaam, United Republic of Tanzania
| | - Pascal Cherpillod
- Laboratory of Virology, Division of Infectious Diseases, University Hospital of Geneva, and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Laurent Kaiser
- Laboratory of Virology, Division of Infectious Diseases, University Hospital of Geneva, and Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Blaise Genton
- Department of Ambulatory Care and Community Medicine, University of Lausanne, Lausanne, Switzerland
- Infectious Diseases Service, Lausanne University Hospital, Lausanne, Switzerland
- Swiss Tropical and Public Health Institute, University of Basel, Basel, Switzerland
| | - Valérie D’Acremont
- Department of Ambulatory Care and Community Medicine, University of Lausanne, Lausanne, Switzerland
- Swiss Tropical and Public Health Institute, University of Basel, Basel, Switzerland
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8
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9
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Ghai RR, Thurber MI, El Bakry A, Chapman CA, Goldberg TL. Multi-method assessment of patients with febrile illness reveals over-diagnosis of malaria in rural Uganda. Malar J 2016; 15:460. [PMID: 27604542 PMCID: PMC5015337 DOI: 10.1186/s12936-016-1502-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 08/25/2016] [Indexed: 11/10/2022] Open
Abstract
Background Health clinics in rural Africa are typically resource-limited. As a result, many patients presenting with fever are treated with anti-malarial drugs based only on clinical presentation. This is a considerable issue in Uganda, where malaria is routinely over-diagnosed and over-treated, constituting a wastage of resources and an elevated risk of mortality in wrongly diagnosed patients. However, rapid diagnostic tests (RDTs) for malaria are increasingly being used in health facilities. Being fast, easy and inexpensive, RDTs offer the opportunity for feasible diagnostic capacity in resource-limited areas. This study evaluated the rate of malaria misdiagnosis and the accuracy of RDTs in rural Uganda, where presumptive diagnosis still predominates. Specifically, the diagnostic accuracy of “gold standard” methods, microscopy and PCR, were compared to the most feasible method, RDTs. Methods Patients presenting with fever at one of two health clinics in the Kabarole District of Uganda were enrolled in this study. Blood was collected by finger prick and used to administer RDTs, make blood smears for microscopy, and blot Whatman FTA cards for DNA extraction, polymerase chain reaction (PCR) amplification, and sequencing. The accuracy of RDTs and microscopy were assessed relative to PCR, considered the new standard of malaria diagnosis. Results A total of 78 patients were enrolled, and 31 were diagnosed with Plasmodium infection by at least one method. Comparing diagnostic pairs determined that RDTs and microscopy performed similarly, being 92.6 and 92.0 % sensitive and 95.5 and 94.4 % specific, respectively. Combining both methods resulted in a sensitivity of 96.0 % and specificity of 100 %. However, both RDTs and microscopy missed one case of non-falciparum malaria (Plasmodium malariae) that was identified and characterized by PCR and sequencing. In total, based on PCR, 62.0 % of patients would have been misdiagnosed with malaria if symptomatic diagnosis was used. Conclusions Results suggest that diagnosis of malaria based on symptoms alone appears to be highly inaccurate in this setting. Furthermore, RDTs were very effective at diagnosing malaria, performing as well or better than microscopy. However, only PCR and DNA sequencing detected non-P. falciparum species, which highlights an important limitation of this test and a treatment concern for non-falciparum malaria patients. Nevertheless, RDTs appear the only feasible method in rural or resource-limited areas, and therefore offer the best way forward in malaria management in endemic countries.
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Affiliation(s)
- Ria R Ghai
- Department of Environmental Sciences, Emory University, Atlanta, GA, 30322, USA. .,Department of Biology, McGill University, Montreal, QC, H3A 1B1, Canada.
| | - Mary I Thurber
- School of Veterinary Medicine, University of California Davis, 1 Shields Avenue, Davis, CA, 95616, USA
| | - Azza El Bakry
- JD Maclean Centre for Tropical Diseases, McGill University, Montreal General Hospital, Montreal, QC, H3G 1A4, Canada
| | - Colin A Chapman
- Department of Anthropology and McGill School of Environment, McGill University, Montreal, QC, H3A 2T7, Canada.,Makerere University Biological Field Station, PO Box 967, Kampala, Uganda.,Wildlife Conservation Society, 2300 Southern Boulevard, Bronx, NY, 10460, USA
| | - Tony L Goldberg
- Makerere University Biological Field Station, PO Box 967, Kampala, Uganda.,Department of Pathobiological Sciences and Global Health Institute, University of Wisconsin-Madison, Madison, WI, 53706, USA
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10
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Iroh Tam PY, Obaro SK, Storch G. Challenges in the Etiology and Diagnosis of Acute Febrile Illness in Children in Low- and Middle-Income Countries. J Pediatric Infect Dis Soc 2016; 5:190-205. [PMID: 27059657 PMCID: PMC7107506 DOI: 10.1093/jpids/piw016] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 03/04/2016] [Indexed: 01/01/2023]
Abstract
Acute febrile illness is a common cause of hospital admission, and its associated infectious causes contribute to substantial morbidity and death among children worldwide, especially in low- and middle-income countries. Declining transmission of malaria in many regions, combined with the increasing use of rapid diagnostic tests for malaria, has led to the increasing recognition of leptospirosis, rickettsioses, respiratory viruses, and arboviruses as etiologic agents of fevers. However, clinical discrimination between these etiologies can be difficult. Overtreatment with antimalarial drugs is common, even in the setting of a negative test result, as is overtreatment with empiric antibacterial drugs. Viral etiologies remain underrecognized and poorly investigated. More-sensitive diagnostics have led to additional dilemmas in discriminating whether a positive test result reflects a causative pathogen. Here, we review and summarize the current epidemiology and focus particularly on children and the challenges for future research.
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Affiliation(s)
- Pui-Ying Iroh Tam
- Department of Pediatrics
,
University of Minnesota Medical School
,
Minneapolis,Corresponding Author:
Pui-Ying Iroh Tam, MD, 3-210 MTRF, 2001 6th St. SE, Minneapolis, MN 55455. E-mail:
| | - Stephen K. Obaro
- Department of Pediatrics, University of Nebraska Medical Center, Omaha
| | - Gregory Storch
- Department of Pediatrics
,
Washington University School of Medicine
,
St Louis, Missouri
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11
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Zha Y, Zhou M, Hari A, Jacobsen B, Mitragotri N, Rivas B, Ventura OG, Boughton J, Fox JC. Ultrasound diagnosis of malaria: examination of the spleen, liver, and optic nerve sheath diameter. World J Emerg Med 2015; 6:10-5. [PMID: 25802560 PMCID: PMC4369524 DOI: 10.5847/wjem.j.1920-8642.2015.01.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 11/28/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Over 90% of all cases of malaria worldwide occur in Africa. Current methods of diagnosis are time and labor intensive, and could lead to delayed treatment. METHODS In this study we investigated the effectiveness of measurements of spleen, liver, and optic nerve sheath diameter (ONSD) in identifying patients with malaria or severe malaria through the use of hand-held ultrasound devices. We recruited 40 adult patients with malaria and 16 adult control subjects at two hospitals in Mwanza, Tanzania. Ultrasonographic diagnosis was compared with rapid antigen diagnostic test and peripheral blood smear as the gold standards. An receiver operating characteristic curve test was performed to determine the most optimal diagnostic threshold for malaria and severe malaria, using each of the measurements for liver size, spleen size, and ONSD. The thresholds were determined to be >12 cm for spleen length and >15.1 cm for liver length, whereas ONSD was not significant in this study. RESULTS The sensitivities for malaria diagnosis were 66.7% and 58.3% for liver and spleen length respectively, suggesting that these measurements may not be suitable for identifying patients with severe malaria. However, the high specificity of 90.9% for spleen length and the acceptable specificity of 75.0% for liver length suggest that these measurements can be used as a method to eliminate false-positive diagnoses (i.e. patients who do not have severe malaria but are classified as having it by a test with a high sensitivity), giving a high positive predictive value. CONCLUSIONS We report a high specificity for spleen size and a moderate specificity for liver size in the ultrasonographic diagnosis of severe malaria. Thus when paired with a highly sensitive method of malaria diagnosis, ultrasonographic measurement of spleen and liver size is promising as part of a diagnostic algorithm for malaria. It could be used to stratify risk in patients diagnosed with malaria and assist in their triage. If no sensitive tests are available, ultrasound might be useful to suggest malaria as a cause of a patient's constellation of clinical symptoms.
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Affiliation(s)
- Yuanting Zha
- Irvine School of Medicine, University of California, 1001 Health Sciences Road, 252 Irvine Hall, Irvine, CA 92697, USA
| | - Michelle Zhou
- Irvine School of Medicine, University of California, 1001 Health Sciences Road, 252 Irvine Hall, Irvine, CA 92697, USA
| | - Anjali Hari
- Irvine School of Medicine, University of California, 1001 Health Sciences Road, 252 Irvine Hall, Irvine, CA 92697, USA
| | - Bradley Jacobsen
- Irvine School of Medicine, University of California, 1001 Health Sciences Road, 252 Irvine Hall, Irvine, CA 92697, USA
| | - Neha Mitragotri
- Irvine School of Medicine, University of California, 1001 Health Sciences Road, 252 Irvine Hall, Irvine, CA 92697, USA
| | - Bianca Rivas
- Irvine School of Medicine, University of California, 1001 Health Sciences Road, 252 Irvine Hall, Irvine, CA 92697, USA
| | - Olga Gabriela Ventura
- Irvine School of Medicine, University of California, 1001 Health Sciences Road, 252 Irvine Hall, Irvine, CA 92697, USA
| | - Janice Boughton
- Gritman Medical Center, 700 S Main Street, Moscow, ID, 83843, USA
| | - John Christian Fox
- Irvine School of Medicine, University of California, 1001 Health Sciences Road, 252 Irvine Hall, Irvine, CA 92697, USA
- Department of Emergency Medicine, Irvine Medical Center, University of California, 101 The City Drive, Orange, CA, 92868, USA
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12
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Singh S, Madaki AJK, Jiya NM, Singh R, Thacher TD. Predictors of malaria in febrile children in Sokoto, Nigeria. Niger Med J 2014; 55:480-5. [PMID: 25538366 PMCID: PMC4262844 DOI: 10.4103/0300-1652.144701] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Background: Presumptive diagnosis of malaria is widespread, even where microscopy is available. As fever is very nonspecific, this often leads to over diagnosis, drug wastage and loss of opportunity to consider alternative causes of fever, hence the need to improve on the clinical diagnosis of malaria. Materials and Methods: In a prospective cross-sectional comparative study, we examined 45 potential predictors of uncomplicated malaria in 800 febrile children (0-12 years) in Sokoto, Nigeria. We developed a clinical algorithm for malaria diagnosis and compared it with a validated algorithm, Olaleye's model. Results: Malaria was confirmed in 445 (56%). In univariate analysis, 13 clinical variables were associated with malaria. In multivariate analysis, vomiting (odds ratio, OR 2.6), temperature ≥ 38.5°C (OR 2.2), myalgia (OR 1.8), weakness (OR 1.9), throat pain (OR 1.8) and absence of lung crepitations (OR 5.6) were independently associated with malaria. In children over age 3 years, any 3 predictors had a sensitivity of 82% and specificity of 47% for malaria. An Olaleye score ≥ 5 had a sensitivity of 62% and a specificity of 51%. Conclusion: In hyperendemic areas, the sensitivity of our algorithm may permit presumptive diagnosis of malaria in children. Algorithm positive cases can be presumptively treated, and negative cases can undergo parasitological testing to determine need for treatment.
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Affiliation(s)
- Sanjay Singh
- Department of Family Medicine, Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria
| | - Aboi J K Madaki
- Department of Family Medicine, Jos University Teaching Hospital, Jos, Nigeria
| | - Nma M Jiya
- Department of Paediatrics, Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria
| | - Rupashree Singh
- Department of Biological Sciences, Kebbi State University of Science and Technology, Aliero, Nigeria
| | - Tom D Thacher
- Department of Family Medicine, Mayo Clinic, Rochester, Minnesota, USA
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Kempinska-Podhorodecka A, Knap O, Drozd A, Kaczmarczyk M, Parafiniuk M, Parczewski M, Milkiewicz M. Analysis of the genetic variants of glucose-6-phosphate dehydrogenase in inhabitants of the 4th Nile cataract region in Sudan. Blood Cells Mol Dis 2012; 50:115-8. [PMID: 23146719 DOI: 10.1016/j.bcmd.2012.10.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 08/28/2012] [Accepted: 08/28/2012] [Indexed: 10/27/2022]
Abstract
Malaria is one of the most common diseases in the African population. Genetic variance in glucose dehydrogenase 6-phosphate (G6PD) in humans determines the response to malaria exposure. In this study, we aimed to analyze the frequency of two single-nucleotide polymorphisms (G202A and A376G) present in two local tribes of Sudanese Arabs from the region of the 4th Nile cataract in Sudan, the Shagia and Manasir. The polymorphisms in G6PD were analyzed in 217 individuals (126 representatives of the Shagia tribe and 91 of the Manasir tribe). Real-time PCR and RFLP-PCR were utilized to analyze significant differences in the prevalence of alleles and genotypes. The 202A G6P allele frequency was 0.7%, whereas the G202 variant was found in 93.3% of cases. The AA, GA, and GG genotype frequencies for the A376G G6PD codon among the Shagia were 88, 11.1, and 0.9%, respectively; this is similar to the distribution among Manasir tribe representatives (94.5, 3.3, and 2.2%, respectively; OR 3.44 [0.85-16.17], p=0.6). Notably, in north-eastern Sudan the G6PD B (202G/376A) compound genotype frequency was 90.3%, whereas the G6PD A variant (202G/376G) was found in 1.4% of that population. Identification of the G6PD A- variant (202A/376G) in the isolated Shagia tribe provides important information regarding the tribal ancestry. Taken together, the data presented in this study suggest that the Shagia tribe was still nomadic between 4000 and 12,000 years ago. Moreover, the lack of G6PD A- genotype among ethnically diverse Monasir tribesmen indicates a separation of the Shagia from the other tribes in the region of the 4th Nile cataract in Sudan.
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Vinnemeier CD, Schwarz NG, Sarpong N, Loag W, Acquah S, Nkrumah B, Huenger F, Adu-Sarkodie Y, May J. Predictive value of fever and palmar pallor for P. falciparum parasitaemia in children from an endemic area. PLoS One 2012; 7:e36678. [PMID: 22574213 PMCID: PMC3344934 DOI: 10.1371/journal.pone.0036678] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 04/05/2012] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Although the incidence of Plasmodium falciparum malaria in some parts of sub-Saharan Africa is reported to decline and other conditions, causing similar symptoms as clinical malaria are gaining in relevance, presumptive anti-malarial treatment is still common. This study traced for age-dependent signs and symptoms predictive for P. falciparum parasitaemia. METHODS In total, 5447 visits of 3641 patients between 2-60 months of age who attended an outpatient department (OPD) of a rural hospital in the Ashanti Region, Ghana, were analysed. All Children were examined by a paediatrician and a full blood count and thick smear were done. A Classification and Regression Tree (CART) model was used to generate a clinical decision tree to predict malarial parasitaemia a7nd predictive values of all symptoms were calculated. RESULTS Malarial parasitaemia was detected in children between 2-12 months and between 12-60 months of age with a prevalence of 13.8% and 30.6%, respectively. The CART-model revealed age-dependent differences in the ability of the variables to predict parasitaemia. While palmar pallor was the most important symptom in children between 2-12 months, a report of fever and an elevated body temperature of ≥37.5°C gained in relevance in children between 12-60 months. The variable palmar pallor was significantly (p<0.001) associated with lower haemoglobin levels in children of all ages. Compared to the Integrated Management of Childhood Illness (IMCI) algorithm the CART-model had much lower sensitivities, but higher specificities and positive predictive values for a malarial parasitaemia. CONCLUSIONS Use of age-derived algorithms increases the specificity of the prediction for P. falciparum parasitaemia. The predictive value of palmar pallor should be underlined in health worker training. Due to a lack of sensitivity neither the best algorithm nor palmar pallor as a single sign are eligible for decision-making and cannot replace presumptive treatment or laboratory diagnosis.
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Maguire JL, Kulik DM, Laupacis A, Kuppermann N, Uleryk EM, Parkin PC. Clinical prediction rules for children: a systematic review. Pediatrics 2011; 128:e666-77. [PMID: 21859912 DOI: 10.1542/peds.2011-0043] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
CONTEXT The degree to which clinical prediction rules (CPRs) for children meet published standards is unclear. OBJECTIVE To systematically review the quality, performance, and validation of published CPRs for children, compare them with adult CPRs, and suggest pediatric-specific changes to CPR methodology. METHODS Medline was searched from 1950 to 2011. Studies were selected if they included the development of a CPR involving children younger than 18 years. Two investigators assessed study quality, rule performance, and rule validation as methodologic standards. RESULTS Of 7298 titles and abstracts assessed, 137 eligible studies were identified. They describe the development of 101 CPRs addressing 36 pediatric conditions. Quality standards met in fewer than half of the studies were blind assessment of predictors (47%), reproducibility of predictors (18%), blind assessment of outcomes (42%), adequate follow-up of outcomes (36%), adequate power (43%), adequate reporting of results (49%), and 95% confidence intervals reported (36%). For rule performance, 48% had a sensitivity greater than 0.95, and 43% had a negative likelihood ratio less than 0.1. For rule validation, 76% had no validation, 17% had narrow validation, 8% had broad validation, and none had impact analysis performed. Compared with CPRs for adult health conditions, quality and rule validation seem to be lower. CONCLUSIONS Many CPRs have been derived for children, but few have been validated. Relative to adult CPRs, several quality indicators demonstrated weaknesses. Existing performance standards may prove elusive for CPRs that involve children. CPRs for children that are more assistive and less directive and include patients' values and preferences in decision-making may be helpful.
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Affiliation(s)
- Jonathon L Maguire
- Department of Pediatrics, Li Ka Shing Knowledge Institute, St Michael's Hospital, Toronto, Ontario, Canada.
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Elmardi KA, Noor AM, Githinji S, Abdelgadir TM, Malik EM, Snow RW. Self-reported fever, treatment actions and malaria infection prevalence in the northern states of Sudan. Malar J 2011; 10:128. [PMID: 21575152 PMCID: PMC3115918 DOI: 10.1186/1475-2875-10-128] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Accepted: 05/15/2011] [Indexed: 11/03/2022] Open
Abstract
Background The epidemiology of fevers and their management in areas of low malaria transmission in Africa is not well understood. The characteristics of fever, its treatment and association with infection prevalence from a national household sample survey in the northern states of Sudan, an area that represents historically low parasite prevalence, are examined in this study. Methods In October-November 2009, a cluster sample cross-sectional household malaria indicator survey was undertaken in the 15 northern states of the Sudan. Data on household assets and individual level information on age, sex, whether the individual had a fever in the last 14 days and on the day of survey, actions taken to treat the fever including diagnostic services and drugs used and their sources were collected. Consenting household members were asked to provide a finger-prick blood sample and examined for malaria parasitaemia using a rapid diagnostic test (RDT). All proportions and odds ratios were weighted and adjusted for clustering. Results Of 26,471 respondents 19% (n = 5,299) reported a history of fever within the last two weeks prior to the survey and 8% had fever on the day of the survey. Only 39% (n = 2,035) of individuals with fever in last two weeks took any action, of which 43% (n = 875) were treated with anti-malarials. About 44% (n = 382) of malaria treatments were done using the nationally recommended first-line therapy artesunate+sulphadoxine-pryrimethamine (AS+SP) and 13% (n = 122) with non-recommended chloroquine or SP. Importantly 33.9% (n = 296) of all malaria treatments included artemether monotherapy, which is internationally banned for the treatment of uncomplicated malaria. About 53% of fevers had some form of parasitological diagnosis before treatment. On the day of survey, 21,988 individuals provided a finger-prick blood sample and only 1.8% were found positive for Plasmodium falciparum. Infection prevalence was higher among individuals who had fever in the last two weeks (OR = 3.4; 95%CI = 2.6 - 4.4, p < 0.001) or reported fever on the day of survey (OR = 6.2; 95%CI = 4.4 - 8.7, p < 0.001) compared to those without a history of fever. Conclusion Across the northern states of the Sudan, the period prevalence of fever is low. The proportion of fevers that are likely to be malaria is very low. Consequently, parasitological diagnosis of all fevers before treatment is an appropriate strategy for malaria case-management. Improved regulation and supervision of health workers is required to increase the use of diagnostics and remove the practice of prescribing artemisinin monotherapy.
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Affiliation(s)
- Khalid A Elmardi
- National Malaria Control Programme, Federal Ministry of Health, PO Box 1204 Khartoum, Sudan
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D'Acremont V, Lengeler C, Genton B. Reduction in the proportion of fevers associated with Plasmodium falciparum parasitaemia in Africa: a systematic review. Malar J 2010; 9:240. [PMID: 20727214 PMCID: PMC2936918 DOI: 10.1186/1475-2875-9-240] [Citation(s) in RCA: 143] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2010] [Accepted: 08/22/2010] [Indexed: 11/16/2022] Open
Abstract
Background Malaria is almost invariably ranked as the leading cause of morbidity and mortality in Africa. There is growing evidence of a decline in malaria transmission, morbidity and mortality over the last decades, especially so in East Africa. However, there is still doubt whether this decline is reflected in a reduction of the proportion of malaria among fevers. The objective of this systematic review was to estimate the change in the Proportion of Fevers associated with Plasmodium falciparum parasitaemia (PFPf) over the past 20 years in sub-Saharan Africa. Methods Search strategy. In December 2009, publications from the National Library of Medicine database were searched using the combination of 16 MeSH terms. Selection criteria. Inclusion criteria: studies 1) conducted in sub-Saharan Africa, 2) patients presenting with a syndrome of 'presumptive malaria', 3) numerators (number of parasitologically confirmed cases) and denominators (total number of presumptive malaria cases) available, 4) good quality microscopy. Data collection and analysis. The following variables were extracted: parasite presence/absence, total number of patients, age group, year, season, country and setting, clinical inclusion criteria. To assess the dynamic of PFPf over time, the median PFPf was compared between studies published in the years ≤2000 and > 2000. Results 39 studies conducted between 1986 and 2007 in 16 different African countries were included in the final analysis. When comparing data up to year 2000 (24 studies) with those afterwards (15 studies), there was a clear reduction in the median PFPf from 44% (IQR 31-58%; range 7-81%) to 22% (IQR 13-33%; range 2-77%). This dramatic decline is likely to reflect a true change since stratified analyses including explanatory variables were performed and median PFPfs were always lower after 2000 compared to before. Conclusions There was a considerable reduction of the proportion of malaria among fevers over time in Africa. This decline provides evidence for the policy change from presumptive anti-malarial treatment of all children with fever to laboratory diagnosis and treatment upon result. This should insure appropriate care of non-malaria fevers and rationale use of anti-malarials.
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Okiro EA, Snow RW. The relationship between reported fever and Plasmodium falciparum infection in African children. Malar J 2010; 9:99. [PMID: 20398428 PMCID: PMC2867992 DOI: 10.1186/1475-2875-9-99] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Accepted: 04/19/2010] [Indexed: 11/15/2022] Open
Abstract
Background Fever has traditionally served as the entry point for presumptive treatment of malaria in African children. However, recent changes in the epidemiology of malaria across many places in Africa would suggest that the predictive accuracy of a fever history as a marker of disease has changed prompting calls for the change to diagnosis-based treatment strategies. Methods Using data from six national malaria indicator surveys undertaken between 2007 and 2009, the relationship between childhood (6-59 months) reported fever on the day of survey and the likelihood of coincidental Plasmodium falciparum infection recorded using a rapid diagnostic test was evaluated across a range of endemicities characteristic of Africa today. Results Of 16,903 children surveyed, 3% were febrile and infected, 9% were febrile without infection, 12% were infected but were not febrile and 76% were uninfected and not febrile. Children with fever on the day of the survey had a 1.98 times greater chance of being infected with P. falciparum compared to children without a history of fever on the day of the survey after adjusting for age and location (OR 1.98; 95% CI 1.74-2.34). There was a strong linear relationship between the percentage of febrile children with infection and infection prevalence (R2 = 0.9147). The prevalence of infection in reported fevers was consistently greater than would be expected solely by chance and this increased with increasing transmission intensity. The data suggest that in areas where community-based infection prevalence in childhood is above 34-37%, 50% or more of fevers are likely to be associated with infection. Conclusion The potential benefits of diagnosis will depend on the prevalence of infection among children who report fever. The study has demonstrated a predictable relationship between parasite prevalence in the community and risks of infection among febrile children suggesting that current maps of parasite prevalence could be used to guide diagnostic strategies in Africa.
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Affiliation(s)
- Emelda A Okiro
- Malaria Public Health & Epidemiology Group, Centre for Geographic Medicine Research - Coast, Kenya Medical Research Institute/Wellcome Trust Research Programme, PO Box 43640, 00100 GPO, Nairobi, Kenya.
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Long EG. Requirements for diagnosis of malaria at different levels of the laboratory network in Africa. Am J Clin Pathol 2009; 131:858-60. [PMID: 19461094 DOI: 10.1309/ajcpvx71bxwovwby] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The rapid increase of resistance to cheap, reliable antimalarials, the increasing cost of effective drugs, and the low specificity of clinical diagnosis has increased the need for more reliable diagnostic methods for malaria. The most commonly used and most reliable remains microscopic examination of stained blood smears, but this technique requires skilled personnel, precision instruments, and ideally a source of electricity. Microscopy has the advantage of enabling the examiner to identify the species, stage, and density of an infection. An alternative to microscopy is the rapid diagnostic test (RDT), which uses a labeled monoclonal antibody to detect circulating parasitic antigens. This test is most commonly used to detect Plasmodium falciparum infections and is available in a plastic cassette format. Both microscopy and RDTs should be available at all levels of laboratory service in endemic areas, but in peripheral laboratories with minimally trained staff, the RDT may be a more practical diagnostic method.
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Affiliation(s)
- Earl G. Long
- Malaria Branch, Division of Parasitic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA
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Msellem MI, Mårtensson A, Rotllant G, Bhattarai A, Strömberg J, Kahigwa E, Garcia M, Petzold M, Olumese P, Ali A, Björkman A. Influence of rapid malaria diagnostic tests on treatment and health outcome in fever patients, Zanzibar: a crossover validation study. PLoS Med 2009; 6:e1000070. [PMID: 19399156 PMCID: PMC2667629 DOI: 10.1371/journal.pmed.1000070] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Accepted: 03/20/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The use of rapid diagnostic tests (RDTs) for Plasmodium falciparum malaria is being suggested to improve diagnostic efficiency in peripheral health care settings in Africa. Such improved diagnostics are critical to minimize overuse and thereby delay development of resistance to artemisinin-based combination therapies (ACTs). Our objective was to study the influence of RDT-aided malaria diagnosis on drug prescriptions, health outcomes, and costs in primary health care settings. METHODS AND FINDINGS We conducted a cross-over validation clinical trial in four primary health care units in Zanzibar. Patients of all ages with reported fever in the previous 48 hours were eligible and allocated alternate weeks to RDT-aided malaria diagnosis or symptom-based clinical diagnosis (CD) alone. Follow-up was 14 days. ACT was to be prescribed to patients diagnosed with malaria in both groups. Statistical analyses with multilevel modelling were performed. A total of 1,887 patients were enrolled February through August 2005. RDT was associated with lower prescription rates of antimalarial treatment than CD alone, 361/1005 (36%) compared with 752/882 (85%) (odds ratio [OR] 0.04, 95% confidence interval [CI] 0.03-0.05, p<0.001). Prescriptions of antibiotics were higher after RDT than CD alone, i.e., 372/1005 (37%) and 235/882 (27%) (OR 1.8, 95%CI 1.5-2.2, p<0.001), respectively. Reattendance due to perceived unsuccessful clinical cure was lower after RDT 25/1005 (2.5%), than CD alone 43/882 (4.9%) (OR 0.5, 95% CI 0.3-0.9, p = 0.005). Total average cost per patient was similar: USD 2.47 and 2.37 after RDT and CD alone, respectively. CONCLUSIONS RDTs resulted in improved adequate treatment and health outcomes without increased cost per patient. RDTs may represent a tool for improved management of patients with fever in peripheral health care settings. TRIAL REGISTRATION (Clinicaltrials.gov) NCT00549003.
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Affiliation(s)
- Mwinyi I. Msellem
- Malaria Control Programme, Ministry of Health and Social Welfare, Zanzibar, Tanzania
- Infectious Diseases Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Andreas Mårtensson
- Infectious Diseases Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
- Division of International Health, Department of Public Health Sciences, Karolinska Institutet, Stockholm
| | | | - Achuyt Bhattarai
- Infectious Diseases Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Johan Strömberg
- Infectious Diseases Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Elizeus Kahigwa
- World Health Organization (WHO) Country Office, Dar es Salaam, Tanzania
| | | | - Max Petzold
- Nordic School of Public Health, Gothenburg, Sweden
| | | | - Abdullah Ali
- Malaria Control Programme, Ministry of Health and Social Welfare, Zanzibar, Tanzania
| | - Anders Björkman
- Infectious Diseases Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
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Nankabirwa J, Zurovac D, Njogu JN, Rwakimari JB, Counihan H, Snow RW, Tibenderana JK. Malaria misdiagnosis in Uganda--implications for policy change. Malar J 2009; 8:66. [PMID: 19371426 PMCID: PMC2671516 DOI: 10.1186/1475-2875-8-66] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Accepted: 04/16/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In Uganda, like in many other countries traditionally viewed as harbouring very high malaria transmission, the norm has been to recommend that febrile episodes are diagnosed as malaria. In this study, the policy implications of such recommendations are revisited. METHODS A cross-sectional survey was undertaken at outpatient departments of all health facilities in four Ugandan districts. The routine diagnostic practices were assessed for all patients during exit interviews and a research slide was obtained for later reading. Primary outcome measures were the accuracy of national recommendations and routine malaria diagnosis in comparison with the study definition of malaria (any parasitaemia on expert slide examination in patient with fever) stratified by age and intensity of malaria transmission. Secondary outcome measures were the use, interpretation and accuracy of routine malaria microscopy. RESULTS 1,763 consultations undertaken by 233 health workers at 188 facilities were evaluated. The prevalence of malaria was 24.2% and ranged between 13.9% in patients >or=5 years in medium-to-high transmission areas to 50.5% for children <5 years in very high transmission areas. Overall, the sensitivity and negative predictive value (NPV) of routine malaria diagnosis were high (89.7% and 91.6% respectively) while the specificity and positive predictive value (PPV) were low (35.6% and 30.8% respectively). However, malaria was under-diagnosed in 39.9% of children less than five years of age in the very high transmission area. At 48 facilities with functional microscopy, the use of malaria slide examination was low (34.5%) without significant differences between age groups, or between patients for whom microscopy is recommended or not. 96.2% of patients with a routine positive slide result were treated for malaria but also 47.6% with a negative result. CONCLUSION Current recommendations and associated clinical practices result in massive malaria over-diagnosis across all age groups and transmission areas in Uganda. Yet, under-diagnosis is also common in children <5 years. The potential benefits of malaria microscopy are not realized. To address malaria misdiagnosis, Uganda's policy shift from presumptive to parasitological diagnosis should encompass introduction of malaria rapid diagnostic tests and substantial strengthening of malaria microscopy.
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Affiliation(s)
- Joan Nankabirwa
- Malaria Consortium, Africa Regional Office, Kampala, Uganda.
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Perkins MD, Bell DR. Working without a blindfold: the critical role of diagnostics in malaria control. Malar J 2008; 7 Suppl 1:S5. [PMID: 19091039 PMCID: PMC2604880 DOI: 10.1186/1475-2875-7-s1-s5] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Diagnostic testing for malaria has for many years been eschewed, lest it be an obstacle to the delivery of rapid, life-saving treatment. The approach of treating malaria without confirmatory testing has been reinforced by the availability of inexpensive treatment with few side effects, by the great difficulty of establishing quality-assured microscopy in rural and resource-poor settings, and by the preeminence of malaria as a cause of important fever in endemic regions. Within the last decade, all three of these factors have changed. More expensive artemisinin combination therapy (ACT) has been widely introduced, simple immunochromatographic tests for malaria have been developed that can be used as an alternative to microscopy by village health workers, and recognition of the health cost of mismanaging non-malarial fever is growing. In most of the world a small fraction of fever is due to malaria, and reflex treatment with ACT does not make medical or economic sense. Global malaria control efforts have been energized by the availability of new sources of funding, and by the rapid reduction in malaria prevalence in a number of settings where bed nets, indoor residual spraying with insecticides, and ACT have been systematically deployed. This momentum has been captured by a new call for malaria elimination. Without wide implementation of accurate and discriminating diagnostic testing, and reporting of results, most fever will be inappropriately managed, millions of doses of ACT will be wasted, and malaria control programmes will be blindfolded to the impact of their efforts.
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Affiliation(s)
- Mark D Perkins
- Foundation for Innovative New Diagnostics (FIND), Geneva, Switzerland.
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Ngasala B, Mubi M, Warsame M, Petzold MG, Massele AY, Gustafsson LL, Tomson G, Premji Z, Bjorkman A. Impact of training in clinical and microscopy diagnosis of childhood malaria on antimalarial drug prescription and health outcome at primary health care level in Tanzania: a randomized controlled trial. Malar J 2008; 7:199. [PMID: 18831737 PMCID: PMC2566575 DOI: 10.1186/1475-2875-7-199] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Accepted: 10/02/2008] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Prescribing antimalarial medicines based on parasite confirmed diagnosis of malaria is critical to rational drug use and optimal outcome of febrile illness. The impact of microscopy-based versus clinical-based diagnosis of childhood malaria was assessed at primary health care (PHC) facilities using a cluster randomized controlled training intervention trial. METHODS Sixteen PHC facilities in rural Tanzania were randomly allocated to training of health staff in clinical algorithm plus microscopy (Arm-I, n = 5) or clinical algorithm only (Arm-II, n = 5) or no training (Arm-III, n = 6). Febrile under-five children presenting at these facilities were assessed, treated and scheduled for follow up visit after 7 days. Blood smears on day 0 were only done in Arm-I but on Day 7 in all arms. Primary outcome was antimalarial drug prescription. Other outcomes included antibiotic prescription and health outcome. Multilevel regression models were applied with PHC as level of clustering to compare outcomes in the three study arms. RESULTS A total of 973, 1,058 and 1,100 children were enrolled in arms I, II and III, respectively, during the study period. Antimalarial prescriptions were significantly reduced in Arm-I (61.3%) compared to Arms-II (95.3%) and III (99.5%) (both P < 0.001), whereas antibiotic prescriptions did not vary significantly between the arms (49.9%, 54.8% and 34.2%, respectively). In Arm-I, 99.1% of children with positive blood smear readings received antimalarial prescriptions and so did 11.3% of children with negative readings. Those with positive readings were less likely to be prescribed antibiotics than those with negative (relative risk = 0.66, 95% confidence interval: 0.55, 0.72). On day 7 follow-up, more children reported symptoms in Arm-I compared to Arm-III, but fewer children had malaria parasitaemia (p = 0.049). The overall sensitivity of microscopy reading at PHC compared to reference level was 74.5% and the specificity was 59.0% but both varied widely between PHCs. CONCLUSION Microscopy based diagnosis of malaria at PHC facilities reduces prescription of antimalarial drugs, and appears to improve appropriate management of non-malaria fevers, but major variation in accuracy of the microscopy readings was found. Lack of qualified laboratory technicians at PHC facilities and the relatively short training period may have contributed to the shortcomings. TRIAL REGISTRATION This study is registered at Clinicaltrials.gov with the identifier NCT00687895.
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Affiliation(s)
- Billy Ngasala
- Infectious Diseases Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
- Department of Parasitology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Marycelina Mubi
- Infectious Diseases Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
- Department of Parasitology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Marian Warsame
- Division of International Health, Karolinska Institutet, Stockholm, Sweden
- Currently at Global Malaria Programme, World Health Organization, Geneva, Switzerland
| | - Max G Petzold
- Division of International Health, Karolinska Institutet, Stockholm, Sweden
- The Nordic school of Public Health, Gothenburg, Sweden
| | - Amos Y Massele
- Department of Pharmacology, Muhimbili University College of Health Sciences, Dar es Salaam, Tanzania
| | - Lars L Gustafsson
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska Institute, Stockholm, Sweden
| | - Goran Tomson
- Division of International Health, Karolinska Institutet, Stockholm, Sweden
| | - Zul Premji
- Department of Parasitology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Anders Bjorkman
- Infectious Diseases Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden
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Koram KA, Molyneux ME. When Is “Malaria” Malaria? The Different Burdens of Malaria Infection, Malaria Disease, and Malaria-Like Illnesses. Am J Trop Med Hyg 2007. [DOI: 10.4269/ajtmh.77.6.suppl.1] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- K. A. Koram
- Department of Epidemiology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Lego; Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine, University of Malawi; School of Tropical Medicine, University of Liverpool, United Kingdom
| | - M. E. Molyneux
- Department of Epidemiology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Lego; Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine, University of Malawi; School of Tropical Medicine, University of Liverpool, United Kingdom
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Gerstl S, Cohuet S, Edoh K, Brasher C, Lesage A, Guthmann JP, Checchi F. Community coverage of an antimalarial combination of artesunate and amodiaquine in Makamba Province, Burundi, nine months after its introduction. Malar J 2007; 6:94. [PMID: 17640357 PMCID: PMC1948001 DOI: 10.1186/1475-2875-6-94] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Accepted: 07/18/2007] [Indexed: 11/23/2022] Open
Abstract
Background In 2003, artesunate-amodiaquine (AS+AQ) was introduced as the new first-line treatment for uncomplicated malaria in Burundi. After confirmed diagnosis, treatment was delivered at subsidized prices in public health centres. Nine months after its implementation a study was carried out to assess whether children below five years of age with uncomplicated malaria were actually receiving AS+AQ. Methods A community-based study was conducted in Makamba province. Randomly selected households containing one or more children under five with reported fever onset within fourteen days before the study date were eligible. Case-management information was collected based on caregiver recall. A case definition of symptomatic malaria from observations of children presenting a confirmed malaria episode on the day of the survey was developed. Based on this definition, those children who had probable malaria among those with fever onset in the 14 days prior to the study were identified retrospectively. Treatment coverage with AS+AQ was then estimated among these probable malaria cases. Results Out of 195 children with fever on the day of the study, 92 were confirmed as true malaria cases and 103 tested negative. The combination of 'loss of appetite', 'sweating', 'shivering' and 'intermittent fever' yielded the highest possible positive predictive value, and was chosen as the case definition of malaria. Out of 526 children who had had fever 14 days prior to the survey, 165 (31.4%) were defined as probable malaria cases using this definition. Among them, 20 (14.1%) had been treated with AS+AQ, 10 with quinine (5%), 68 (41%) received non-malaria treatments, and 67 got traditional treatment or nothing (39.9%). Most people sought treatment from public health centres (23/99) followed by private clinics (15/99, 14.1%). The median price paid for AS+AQ was 0.5 US$. Conclusion AS+AQ was the most common treatment for patients with probable malaria at public health centres, but coverage was low due to low health centre utilisation and apparently inappropriate prescribing. In addition, AS+AQ was given to patients at a price ten times higher than the subsidized price. The availability and proper use of ACTs should be monitored and maximized after their introduction in order to have a significant impact on the burden of malaria.
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Affiliation(s)
| | | | - Kodjo Edoh
- Médecins sans Frontières-France, Paris, France
| | | | | | | | - Francesco Checchi
- Epicentre, Paris, France
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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Larson BA, Amin AA, Noor AM, Zurovac D, Snow RW. The cost of uncomplicated childhood fevers to Kenyan households: implications for reaching international access targets. BMC Public Health 2006; 6:314. [PMID: 17196105 PMCID: PMC1770919 DOI: 10.1186/1471-2458-6-314] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Accepted: 12/29/2006] [Indexed: 12/02/2022] Open
Abstract
Background Fever is the clinical hallmark of malaria disease. The Roll Back Malaria (RBM) movement promotes prompt, effective treatment of childhood fevers as a key component to achieving its optimistic mortality reduction goals by 2010. A neglected concern is how communities will access these new medicines promptly and the costs to poor households when they are located in rural areas distant to health services. Methods We assemble data developed between 2001 and 2002 in Kenya to describe treatment choices made by rural households to treat a child's fever and the related costs to households. Using a cost-of-illness approach, we estimate the expected cost of a childhood fever to Kenyan households in 2002. We develop two scenarios to explore how expected costs to households would change if more children were treated at a health care facility with an effective antimalarial within 48 hours of fever onset. Results 30% of uncomplicated fevers were managed at home with modern medicines, 38% were taken to a health care facility (HCF), and 32% were managed at home without the use of modern medicines. Direct household cash expenditures were estimated at $0.44 per fever, while the total expected cost to households (cash and time) of an uncomplicated childhood fever is estimated to be $1.91. An estimated mean of 1.42 days of caretaker time devoted to each fever accounts for the majority of household costs of managing fevers. The aggregate cost to Kenyan households of managing uncomplicated childhood fevers was at least $96 million in 2002, equivalent to 1.00% of the Kenyan GDP. Fewer than 8% of all fevers were treated with an antimalarial drug within 24 hours of fever onset, while 17.5% were treated within 48 hours at a HCF. To achieve an increase from 17.5% to 33% of fevers treated with an antimalarial drug within 48 hours at a HCF (Scenario 1), children already being taken to a HCF would need to be taken earlier. Under this scenario, direct cash expenditures would not change, and total household costs would fall slightly to $1.86 because caretakers also save time with prompt treatment if the child has malaria. Conclusion The management of uncomplicated childhood fevers imposes substantial costs on Kenyan households. Achieving substantial improvements in the numbers of fevers treated within 48 hours at a HCF with an effective antimalarial drug (Scenario 1) will not impose additional costs on households. Achieving additional improvements in fevers treated promptly at a HCF (Scenario 2) will impose additional costs on some households roughly equal to average cash expenses for transportation to a HCF. Additional financing mechanisms that further reduce the costs of accessing care at a HCF and/or that make artemisinin-based combination therapies (ACTs) accessible for home management need to be developed and evaluated as a top priority.
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Affiliation(s)
- Bruce A Larson
- Center for International Health and Development, Boston University, 85 East Concord Street, 5th Floor, Boston, MA 02118, USA
- Centre for Clinical Research, Kenya Medical Research Institute, PO Box 20778, Nairobi 00202, Kenya
- Department of Agricultural and Resource Economics, Unit 4021, University of Connecticut, Storrs, CT 06269, USA
- Malaria Public Health & Epidemiology Group, Centre for Geographic Medicine Research-Coast, Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, 00100 GPO, Nairobi, Kenya
| | - Abdinasir A Amin
- Malaria Public Health & Epidemiology Group, Centre for Geographic Medicine Research-Coast, Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, 00100 GPO, Nairobi, Kenya
| | - Abdisalan M Noor
- Malaria Public Health & Epidemiology Group, Centre for Geographic Medicine Research-Coast, Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, 00100 GPO, Nairobi, Kenya
| | - Dejan Zurovac
- Malaria Public Health & Epidemiology Group, Centre for Geographic Medicine Research-Coast, Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, 00100 GPO, Nairobi, Kenya
- Centre for Tropical Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, UK
| | - Robert W Snow
- Malaria Public Health & Epidemiology Group, Centre for Geographic Medicine Research-Coast, Kenya Medical Research Institute/Wellcome Trust Research Programme, P.O. Box 43640, 00100 GPO, Nairobi, Kenya
- Centre for Tropical Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, UK
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Zurovac D, Rowe AK. Quality of treatment for febrile illness among children at outpatient facilities in sub-Saharan Africa. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2006; 100:283-96. [PMID: 16762109 DOI: 10.1179/136485906x105633] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
For the prompt and effective management of malaria cases (a key strategy for reducing the enormous burden of the disease), healthworkers must prescribe antimalarial drugs according to evidence-based guidelines. In sub-Saharan Africa, the guidelines for use in outpatient settings generally recommend that febrile illness in children should be suspected to be malaria and be treated with an antimalarial drug. The quality of treatment offered to febrile children at outpatient facilities in this region has now been investigated in a literature review. The results of five methodologically comparable studies were also used to explore the determinants of malaria-treatment practices. The quality of treatment prescribed to febrile children was found to have been generally sub-optimal, with low levels of adherence to national guidelines, the frequent selection of non-recommended antimalarials, and the use of incorrect dosages. Several factors might be to responsible for these shortcomings. Although interventions such as the Integrated Management of Childhood Illness (IMCI) strategy can lead to improvements, a better understanding of the practices of the healthworkers responsible for treating febrile children will be needed before treatment is made much better. The failure to provide treatment of good quality will become an increasingly important problem as antimalarial policies involving drugs with more complex dosing regimens, such as artemisinin-based combination therapies (ACT), are implemented. If the malaria burden in Africa is to be greatly reduced, the deployment of ACT must be accompanied by interventions to ensure the correct treatment of children at the point of care. Some interventions, such as IMCI, can improve the treatment of not only malaria but also other potentially life-threatening illnesses.
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Affiliation(s)
- D Zurovac
- Malaria Public Health and Epidemiology Group, Centre for Geographic Medicine, Kenya Medical Research Institute/Wellcome Trust Research Laboratories, P.O. Box 43640, 00100 GPO, Nairobi, Kenya.
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Filmer D. Fever and its treatment among the more and less poor in sub-Saharan Africa. Health Policy Plan 2005; 20:337-46. [PMID: 16155065 DOI: 10.1093/heapol/czi043] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This paper uses individual and household level data to explore empirically the associations between household wealth and the incidence and treatment of fever, as an indicator of malaria, among children in sub-Saharan Africa. The data used are from Demographic and Health Surveys collected in the 1990s from 22 countries where malaria is prevalent. The results suggest that the incidence of fever and its treatment are related to poverty in sub-Saharan Africa. Incidence is typically lower at the very top of the wealth distribution. The relationship, however, is not strong, especially after controlling for potentially confounding factors. Treatment patterns are strongly related to poverty as wealthier households are more likely to seek care or advice. While it is perhaps unsurprising that treatment from private sources increases with household wealth, government services--despite their public nature--are typically also used more by wealthier households. While general results hold for many of the countries, there is sufficient variation across countries that any policy seeking to reform the health sector in order to better cater to the poor needs to be informed by country-specific work.
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Affiliation(s)
- Deon Filmer
- Development Research Group, The World Bank, 1818 H Street NW, Washington, DC 20433, USA.
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Mwangi TW, Mohammed M, Dayo H, Snow RW, Marsh K. Clinical algorithms for malaria diagnosis lack utility among people of different age groups. Trop Med Int Health 2005; 10:530-6. [PMID: 15941415 PMCID: PMC3521057 DOI: 10.1111/j.1365-3156.2005.01439.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We conducted a study to determine whether clinical algorithms would be useful in malaria diagnosis among people living in an area of moderate malaria transmission within Kilifi District in Kenya. A total of 1602 people of all age groups participated. We took smears and recorded clinical signs and symptoms (prompted or spontaneous) of all those presenting to the study clinic with a history of fever. A malaria case was defined as a person presenting to the clinic with a history of fever and concurrent parasitaemia. A set of clinical signs and symptoms (algorithms) with the highest sensitivity and specificity for diagnosing a malaria case was selected for the age groups =5 years, 6-14 years and >/=15 years. These age-optimized derived algorithms were able to identify about 66% of the cases among those <15 years of age but only 23% of cases among adults. Were these algorithms to be used as a basis for a decision on treatment among those presenting to the clinic, 16% of children =5 years, 44% of those 6-14 years of age and 66% of the adults who had a history of fever and parasitaemia >/=5000 parasites/microl of blood would be sent home without treatment. Clinical algorithms therefore appear to have little utility in malaria diagnosis, performing even worse in the older age groups, where avoiding unnecessary use of anti-malarials would make more drugs available to the really needy population of children under 5 years of age.
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Affiliation(s)
- Tabitha W Mwangi
- Kenya Medical Research Institute, CGMRC/Wellcome Trust Collaborative Program, Kilifi, Kenya.
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Gay-Andrieu F, Adehossi E, Lacroix V, Gagara M, Ibrahim ML, Kourna H, Boureima H. Epidemiological, clinical and biological features of malaria among children in Niamey, Niger. Malar J 2005; 4:10. [PMID: 15703076 PMCID: PMC549526 DOI: 10.1186/1475-2875-4-10] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2004] [Accepted: 02/09/2005] [Indexed: 12/02/2022] Open
Abstract
Background Malaria takes a heavy toll in Niger, one of the world's poorest countries. Previous evaluations conducted in the context of the strategy for the Integrated Management of Childhood Illness, showed that 84% of severe malaria cases and 64 % of ordinary cases are not correctly managed. The aim of this survey was to describe epidemiological, clinical and biological features of malaria among <5 year-old children in the paediatric department of the National Hospital of Niamey, Niger's main referral hospital. Methods The study was performed in 2003 during the rainy season from July 25th to October 25th. Microscopic diagnosis of malaria, complete blood cell counts and measurement of glycaemia were performed in compliance with the routine procedure of the laboratory. Epidemiological data was collected through interviews with mothers. Results 256 children aged 3–60 months were included in the study. Anthropometrics and epidemiological data were typical of a very underprivileged population: 58% of the children were suffering from malnutrition and all were from poor families. Diagnosis of malaria was confirmed by microscopy in 52% of the cases. Clinical symptoms upon admission were non-specific, but there was a significant combination between a positive thick blood smear and neurological symptoms, and between a positive thick blood smear and splenomegaly. Thrombopaenia was also statistically more frequent among confirmed cases of malaria. The prevalence of severe malaria was 86%, including cases of severe anaemia among < 2 year-old children and neurological forms after 2 years of age. Overall mortality was 20% among confirmed cases and 21% among severe cases. Conclusions The study confirmed that malaria was a major burden for the National Hospital of Niamey. Children hospitalized for malaria had an underprivileged background. Two distinctive features were the prevalence of severe malaria and a high mortality rate. Medical and non-medical underlying factors which may explain such a situation are discussed.
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Affiliation(s)
| | - Eric Adehossi
- Department of Internal Medicine, B3, National Hospital of Niamey, Niamey, Niger
| | - Véronique Lacroix
- Clinique Gamkalley, Niamey, Niger
- Université Victor Segalen, Bordeaux 2, Bordeaux, France
| | - Moussa Gagara
- Department of Internal Medicine, B3, National Hospital of Niamey, Niamey, Niger
| | | | - Hama Kourna
- Department of Paediatrics B, National Hospital of Niamey, Niamey, Niger
| | - Hamadou Boureima
- Department of Paediatrics A, National Hospital of Niamey, Niamey, Niger
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Erhart A, Thang ND, Bien TH, Tung NM, Hung NQ, Hung LX, Tuy TQ, Speybroeck N, Cong LD, Coosemans M, D'Alessandro U. Malaria epidemiology in a rural area of the Mekong Delta: a prospective community-based study. Trop Med Int Health 2004; 9:1081-90. [PMID: 15482400 DOI: 10.1111/j.1365-3156.2004.01310.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Over the past 10 years, the Mekong Delta region in Vietnam has experienced fast socio-economic development with subsequent changes in malaria vectors ecology. We conducted a 2-year prospective community-based study in a coastal rural area in the southern Mekong Delta to re-assess the malaria epidemiological situation and the dynamics of transmission. The incidence rate of clinical malaria, established on 558 individuals followed for 23 months by active case detection and biannual cross-sectional surveys, was 2.6/100 person-years. Over the 2-year study period, the parasite rate and malaria seroprevalence (Plasmodium falciparum and P. vivax) decreased significantly from 2.4% to almost 0%. Passive case detection (PCD) of clinical cases and serological follow-up of newborns carried out in a larger population confirmed the low and decreasing trend of malaria transmission. The majority of fever cases were seen in the private sector and most were unnecessarily treated with antimalarials. Training and involvement of the private sector in detection of malaria cases would greatly improve the quality of health care and health information system.
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Affiliation(s)
- A Erhart
- Institute of Tropical Medicine Prince Leopold, Antwerp, Belgium.
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Winstanley P, Ward S, Snow R, Breckenridge A. Therapy of falciparum malaria in sub-saharan Africa: from molecule to policy. Clin Microbiol Rev 2004; 17:612-37, table of contents. [PMID: 15258096 PMCID: PMC452542 DOI: 10.1128/cmr.17.3.612-637.2004] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The burden of falciparum malaria remains as great as ever, and, as has probably always been the case, it is carried mainly by tropical Africa. Of the various means available for the control of malaria, the use of effective drugs remains the most important and is likely to remain so for a considerable time to come. Unfortunately, the extensive development of resistance by the parasite threatens the utility of most of the affordable classes of drug: the development of novel antimalarials has never been more urgently needed. Any attempt to understand the vast complexities of falciparum malaria in Africa requires an ability to think "from molecule to policy." In consequence, the review ambitiously tries to examine the current pharmacopeia, the process by which new drugs are developed and the ways in which drugs are actually used, in both the formal and informal health sectors. The informal sector is particularly important in Africa, where around half of all antimalarial treatments are bought from informal outlets and taken at home without supervision by health care professionals: the potential impact of adherence on clinical outcome is discussed. Given that the full costs are carried by the patient in a large proportion of cases, the importance of drug affordability is explored. The review also discusses the splicing of new drugs into national policy. The various parameters that feed into deliberations on changes in drug policy are discussed.
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Affiliation(s)
- Peter Winstanley
- Department of Pharmacology & Therapeutics, University of Liverpool, Liverpool L69 3GE, United Kingdom.
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Källander K, Nsungwa-Sabiiti J, Peterson S. Symptom overlap for malaria and pneumonia--policy implications for home management strategies. Acta Trop 2004; 90:211-4. [PMID: 15177148 DOI: 10.1016/j.actatropica.2003.11.013] [Citation(s) in RCA: 170] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2003] [Revised: 11/18/2003] [Accepted: 11/21/2003] [Indexed: 11/30/2022]
Abstract
Malaria and pneumonia are the leading causes of child death in Sub-Saharan Africa (SSA). Integrated management of childhood illness (IMCI) at health facilities is presumptive: fever for malaria, and cough/difficult breathing with fast breathing for pneumonia. Of 3671 Ugandan under-fives at 14 health centres, 30% had symptoms compatible both with malaria and pneumonia, necessitating dual treatment. Of 2944 "malaria" cases, 37% also had "pneumonia". The Global Fund and Roll Back Malaria are now supporting home management of malaria strategies across SSA. To adequately treat the sick child, these community strategies need to address the malaria-pneumonia symptom overlap and manage both conditions.
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Affiliation(s)
- Karin Källander
- Karolinska Institutet, Division of International Health (IHCAR), Stockholm 17176, Sweden.
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Hongoro C, McPake B. Hospital costs of high-burden diseases: malaria and pulmonary tuberculosis in a high HIV prevalence context in Zimbabwe. Trop Med Int Health 2003; 8:242-50. [PMID: 12631315 DOI: 10.1046/j.1365-3156.2003.01014.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This paper explores the measurement of hospital costs and efficiency in a context where data is scarce, incomplete or of poor quality. It argues that there is scope for using tracers to examine and compare hospital cost structures and relative efficiency in such contexts. Two high-burden diseases, malaria and pulmonary tuberculosis, are used as tracers to calculate the average costs of inpatient care at selected tertiary hospitals. This study shows that it is feasible to prospectively collect cost data for specific diseases and explore in detail both patient cost distribution and susceptible areas for efficiency improvement. The present study found that the critical source of efficiency variation in public hospitals in Zimbabwe lies in the way hospital beds are used.
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Affiliation(s)
- Charles Hongoro
- Department of Public Health and Policy, London School of Hygiene and Tropical Medicine, UK.
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Guerin PJ, Olliaro P, Nosten F, Druilhe P, Laxminarayan R, Binka F, Kilama WL, Ford N, White NJ. Malaria: current status of control, diagnosis, treatment, and a proposed agenda for research and development. THE LANCET. INFECTIOUS DISEASES 2002; 2:564-73. [PMID: 12206972 DOI: 10.1016/s1473-3099(02)00372-9] [Citation(s) in RCA: 214] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Rolling back malaria is possible. Tools are available but they are not used. Several countries deploy, as their national malaria control treatment policy, drugs that are no longer effective. New and innovative methods of vector control, diagnosis, and treatment should be developed, and work towards development of new drugs and a vaccine should receive much greater support. But the pressing need, in the face of increasing global mortality and general lack of progress in malaria control, is research into the best methods of deploying and using existing approaches, particularly insecticide-treated mosquito nets, rapid methods of diagnosis, and artemisinin-based combination treatments. Evidence on these approaches should provide national governments and international donors with the cost-benefit information that would justify much-needed increases in global support for appropriate and effective malaria control.
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Abstract
Several attempts have been made to identify symptoms and signs based algorithms for diagnosing malaria. In this paper, we review the results of published studies and assess the risks and benefits of this approach in different epidemiological settings. Although in areas with a low prevalence the risk of failure to treat malaria resulting from the use of algorithms was low, the reduction in the wastage of drugs was trivial. The odds of wastage of drugs increased by 1.49 (95% confidence limit 1.45-1.51) for each 10% decrease in the prevalence of malaria. In highly endemic areas the algorithms had a high risk of failure to treat malaria. The odds of failure to treat increased by 1.57 (95% confidence limit 1.50-1.65) for each 10% increase in the prevalence. Furthermore, the best clinical algorithms for diagnosing malaria were site-specific. We conclude that the accuracy of clinical algorithms for diagnosing malaria is not sufficient to determine whether antimalarial drugs should be given to children presenting with febrile illness. In highly endemic areas where laboratory support is not available, the policy of offering antimalarial drugs to all children presenting with a febrile illness recommended by the integrated child management initiative is appropriate.
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Affiliation(s)
- Daniel Chandramohan
- Department of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
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Akpede GO, Akenzua GI. Management of children with prolonged fever of unknown origin and difficulties in the management of fever of unknown origin in children in developing countries. Paediatr Drugs 2001; 3:247-62. [PMID: 11354697 DOI: 10.2165/00128072-200103040-00002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
This is Part II of a 2-part paper on fever of unknown origin (FUO) in children. It examines the aetiology and management of prolonged FUO in children and the difficulties in the management of FUO in children in developing countries. Part I of this paper discussed acute FUO in children and was published in the March 2001 issue of Paediatric Drugs. Prolonged FUO is documented fever of more than 7 to 10 days which has no apparent source and no apparent diagnosis after 1 week of clinical investigations. About 34% of cases of prolonged FUO are caused by infections, with bacterial meningitis and urinary tract infection accounting for about 6.5 and 11.4%, respectively, of cases attributable to infections. Chronic infections, particularly tuberculosis and 'old' disorders such as Kawasaki disease, cat-scratch disease and Epstein-Barr virus infection presenting with 'new' manifestations, collagen-vascular diseases and neoplastic disorders are the other issues of major concern in prolonged FUO. Overall, however, there is a trend towards an increased number of undiagnosed cases. This is due to advancements in diagnostic techniques, such that illnesses which were previously common among the causes of prolonged FUO are now diagnosed earlier, before the presentation becomes that of prolonged FUO. Clinical examination supplemented with laboratory tests to screen for serious bacterial infections should be the mainstay of initial evaluation of children with prolonged FUO. Use of scanning techniques (such as computerised tomography and ultrasound) as additional supplements to this clinical examination may allow for the earlier diagnosis of causes of prolonged FUO in children such as 'occult' abdominal tumours. A common error in management of children with prolonged FUO is the failure to perform a complete history and physical examination; repeated clinical examination and continued observation are of paramount importance in the diagnosis of difficult cases. Major difficulties in the management of FUO in children in developing countries include constraints in the availability and reliability of laboratory tests, cost, misuse of antibiotics and difficulties encountered in the diagnosis of malaria and typhoid fever. Malaria and typhoid fever are major aetiological considerations in both acute and prolonged FUO in children in developing countries. The newer quinolones may hold great promise for the treatment of serious bacterial infections, including meningitis, which are associated with prolonged FUO in developing countries.
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Affiliation(s)
- G O Akpede
- Department of Paediatrics, College of Medicine, Ambrose Alli University, Ekpoma, Nigeria.
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Chandramohan D, Carneiro I, Kavishwar A, Brugha R, Desai V, Greenwood B. A clinical algorithm for the diagnosis of malaria: results of an evaluation in an area of low endemicity. Trop Med Int Health 2001; 6:505-10. [PMID: 11469942 DOI: 10.1046/j.1365-3156.2001.00739.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We conducted a study of 1945 children and 2885 adults who presented with fever to a hospital outpatients clinic in an urban area of India order to develop and evaluate a clinical algorithm for the diagnosis of malaria. Only 139 (7%) children and 349 (12%) adults had microscopically confirmed malaria. None of the symptoms or signs elicited from the respondents were good predictors of clinical malaria. Simple scores were derived through combining clinical features which were associated with slide positivity or were judged by clinicians to be important. The best-performing algorithms were a score of 4 clinical features in children (sensitivity 60.0% and specificity 61.2%) and a score of 5 in adults (sensitivity 54.6% and specificity 57.5%). The clinical features differed and algorithm performances were poorer than in previous studies in highly endemic areas. The conclusion is that malaria diagnosis in areas of low endemicity requires microscopy to be accurate.
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Affiliation(s)
- D Chandramohan
- London School of Hygiene and Tropical Medicine, London, UK.
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Magnussen P, Ndawi B, Sheshe AK, Byskov J, Mbwana K. Malaria diagnosis and treatment administered by teachers in primary schools in Tanzania. Trop Med Int Health 2001; 6:273-9. [PMID: 11348518 DOI: 10.1046/j.1365-3156.2001.00720.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A school health programme in Mwera Division, Pangani District included treatment of malaria attacks occurring in children during school time. A combination of symptoms (headache, muscle/joint pains, feeling feverish) and oral temperature > or = 37.5 degrees C was used for the diagnosis of malaria. Chloroquine (25 mg/kg given over 3 days) was used for treatment. Malariometric surveys on children aged 7-15 years (mean 10 years) were conducted once a year (1995-1997). Plasmodium falciparum accounted for 100% of infections and the parasite prevalence varied between 32.7 and 35.3% from 1995 to 1997. The number of malaria cases (cases/1000 registered school children) diagnosed and treated by school teachers was 159 (67) in 1995, 324 (124) in 1996, 348 (128) in 1997 and 339 (108) in 1998. Children in grades 1-4 (age 7-13) accounted for 64.6% of cases. Symptoms and oral temperature were recorded for 1258 children. Of those, 992 (78.9%) complained of fever and at least one other symptom when presenting to teachers, 98 (7.8%) had fever as their only complaint and 168 (13.5%) presented without a perception of fever, but with other symptoms. Of these children, 36 (21.4%) had a temperature > or =37.5 degrees C. The sensitivity of "feeling feverish" was 96.5% with a specificity of 54.5%. The positive predictive value of feeling feverish was 89.9% and the negative predictive value 78.6%. Blood slides were prepared from 55.3 and 37.2% of children diagnosed by teachers during 1995 and 1996, respectively, and 71.4% were found positive. Among children who fulfilled the algorithm criteria 75.0% had a positive blood slide. With little training and regular supervision it was feasible for school teachers to make a presumptive diagnosis of malaria. We conclude that teachers can play a major role in school health programmes and are willing to be involved in health matters as long as they are supported by health and educational authorities.
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Affiliation(s)
- P Magnussen
- Danish Bilharziasis Laboratory, Jaegersborg Allé 1 D, 2920 Charlottenlund, Denmark.
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Bojang KA, Obaro S, Morison LA, Greenwood BM. A prospective evaluation of a clinical algorithm for the diagnosis of malaria in Gambian children. Trop Med Int Health 2000; 5:231-6. [PMID: 10810013 DOI: 10.1046/j.1365-3156.2000.00538.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Diagnosis of clinical malaria remains difficult, especially in areas where a high proportion of the asymptomatic population have parasitaemia, for the symptoms and signs of malaria overlap with those of other common childhood diseases, such as acute lower respiratory tract infections. However, a study of symptoms and signs in a group of children who presented to Farafenni Health Centre, The Gambia with a history of recent fever identified a group of signs and symptoms which were strong predictors of malaria as opposed to other febrile illnesses. Using these predictors, an algorithm was developed which could be used by fieldworkers and which had a similar sensitivity and specificity for the diagnosis of malaria as that of an experienced paediatrician working without laboratory support. This algorithm has been validated prospectively on 518 children who presented to the Medical Research Council clinic at Basse, The Gambia with fever or a history of recent fever during a 10-month period. A fieldworker obtained a detailed history from the parent or guardian of each child and performed a clinical examination which included measurement of axillary temperature and respiratory rate. Packed cell volume was measured and a thick smear was examined for malaria parasites. A malaria score, based on the presence or absence of malaria-related signs and symptoms, was determined for 382 children who were seen at the clinic during the high transmission season. Using the cut-off score which was optimal during the previous retrospective study, a sensitivity of 70% and a specificity of 77% for a diagnosis of malaria was obtained. The optimal cut-off score for the Basse population was a score of 7; this gave a sensitivity of 88% and a specificity of 62%, figures comparable to those obtained by an experienced paediatrician without laboratory support.
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Affiliation(s)
- K A Bojang
- Medical Research Council Laboratories, Fajara, The Gambia
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Muhe L, Oljira B, Degefu H, Enquesellassie F, Weber MW. Clinical algorithm for malaria during low and high transmission seasons. Arch Dis Child 1999; 81:216-20. [PMID: 10451393 PMCID: PMC1718069 DOI: 10.1136/adc.81.3.216] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To assess the proportion of children with febrile disease who suffer from malaria and to identify clinical signs and symptoms that predict malaria during low and high transmission seasons. STUDY DESIGN 2490 children aged 2 to 59 months presenting to a health centre in rural Ethiopia with fever had their history documented and the following investigations: clinical examination, diagnosis, haemoglobin measurement, and a blood smear for malaria parasites. Clinical findings were related to the presence of malaria parasitaemia. RESULTS Malaria contributed to 5.9% of all febrile cases from January to April and to 30.3% during the rest of the year. Prediction of malaria was improved by simple combinations of a few signs and symptoms. Fever with a history of previous malarial attack or absence of cough or a finding of pallor gave a sensitivity of 83% in the high risk season and 75% in the low risk season, with corresponding specificities of 51% and 60%; fever with a previous malaria attack or pallor or splenomegaly had sensitivities of 80% and 69% and specificities of 65% and 81% in high and low risk settings, respectively. CONCLUSION Better clinical definitions are possible for low malaria settings when microscopic examination cannot be done. Health workers should be trained to detect pallor and splenomegaly because these two signs improve the specificity for malaria.
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Affiliation(s)
- L Muhe
- Department of Paediatrics and Child Health, PO Box 1768, Addis Ababa University, Addis Ababa, Ethiopia
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Kilian AH, Kabagambe G, Byamukama W, Langi P, Weis P, von Sonnenburg F. Application of the ParaSight-F dipstick test for malaria diagnosis in a district control program. Acta Trop 1999; 72:281-93. [PMID: 10232784 DOI: 10.1016/s0001-706x(99)00003-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A rapid test for the diagnosis of Plasmodium falciparum infections based on the detection of histidine-rich-protein II, the ParaSight-F test, was evaluated after introduction in a district malaria control program in Uganda. Suspected treatment failures, pregnant women and infants with clinical malaria and general fever cases were tested at health facilities in malaria hypo-, meso- and holoendemic areas. A total of 1326 tests were carried out by health unit staff, cross read by experienced laboratory staff and results compared with thick film microscopy as the standard. Rater agreement in reading the dipstick result between health unit staff and laboratory staff was high, kappa index 0.94 (0.88-0.99). Sensitivity was 99.6% (99.0-100) for parasite densities above 500/microl, 98.6% (97.7-99.6) for densities above 50/microl and 22.2% (8.6-42.3) for densities below 10/microl. With the applied testing strategies no differences were found between endemicity levels or patient categories. Specificity was 86.2% (83.3-88.8) overall, but significantly higher in general fever cases (92.7%) compared to the other patient groups (84.3%, P=0.009). At the given prevalences positive predictive values (ppv) were above 80% and negative predictive values (npv) above 90% in all cases except in pregnant women (ppv: 77.8%). We conclude that in certain situations this test is an alternative to microscopy to improve diagnostic facilities for case management in malaria control programs in endemic African countries.
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Affiliation(s)
- A H Kilian
- GTZ, Basic Health Services Western Uganda, Fort Portal.
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Olaleye BO, Williams LA, D'Alessandro U, Weber MM, Mulholland K, Okorie C, Langerock P, Bennett S, Greenwood BM. Clinical predictors of malaria in Gambian children with fever or a history of fever. Trans R Soc Trop Med Hyg 1998; 92:300-4. [PMID: 9861403 DOI: 10.1016/s0035-9203(98)91021-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Diagnosis of malaria in children is difficult without laboratory support because the symptoms and signs of malaria overlap with those of other febrile illnesses such as pneumonia. Nevertheless, in many parts of Africa diagnosis of malaria must be made without laboratory investigation. Therefore, a scoring system has been developed to assist peripheral health care workers in making this diagnosis. Four hundred and seven Gambian children aged 6 months to 9 years who presented to a rural clinic with fever or a recent history of fever were investigated. A diagnosis of malaria was made in 159 children who had a fever of 38 degrees C or more and malaria parasitaemia of 5000 parasites/microL or more. Symptoms and signs in children with malaria were compared with those in children with other febrile illnesses to identify features which predicted malaria. Symptoms and signs were incorporated into various logistic regression models to test which were best independent predictors of malaria and these regression models were used to construct simple scoring systems which predicted malaria. A nine terms model predicted clinical malaria with a sensitivity of 89% and a specificity of 61%, values comparable to those obtained by an experienced paediatrician without laboratory support. The ability of peripheral health care workers to diagnose malaria using this approach is now being investigated in a prospective study.
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Affiliation(s)
- B O Olaleye
- MRC Laboratories, Fajara, Banjul, The Gambia
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Luxemburger C, Nosten F, Kyle DE, Kiricharoen L, Chongsuphajaisiddhi T, White NJ. Clinical features cannot predict a diagnosis of malaria or differentiate the infecting species in children living in an area of low transmission. Trans R Soc Trop Med Hyg 1998; 92:45-9. [PMID: 9692150 DOI: 10.1016/s0035-9203(98)90950-6] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The differentiation of malaria from other causes of fever in the absence of microscopy is notoriously difficult. Clinical predictors of malaria have been studied in an area of low and unstable transmission on the western border of Thailand. In 1527 children aged 2-15 years who were followed prospectively for 7 months, 82% (1254) had at least one febrile episode. Malaria caused 24% (301) of the first febrile episodes (Plasmodium falciparum 128, P. vivax 151, P. malariae 1, mixed infections with P. falciparum and P. vivax 21). Each malaria case was matched with the next child of similar age presenting to the dispensary with another cause of fever. Clinical symptoms or signs associated with a final diagnosis of malaria were: confirmed fever (> or = 38 degrees C) (odds ratio [OR] 1.6, 95% confidence interval [95% CI] 1.4-1.9), headache (OR 1.5, 95% CI 1.3-1.9), muscle and/or joint pain (OR 2.0, 95% CI 1.6-2.8), nausea (OR 1.7, 95% CI 1.4-2.3), clinical anaemia (OR 1.4, 95% CI 1.3-3.3), palpable spleen (OR 1.3, 95% CI 1.1-1.7), palpable liver (OR 1.4, 95% CI 1.1-2.1), absence of cough (OR 1.6, 95% CI 1.4-2.0), and absence of diarrhoea (OR 1.5, 95% CI 1.2-2.4). None of these signs alone or in combination proved a good predictor of malaria. The best diagnostic algorithms (history of fever and headache without cough, and history of fever with an oral temperature > or = 38 degrees C [sensitivity 51% for both, specificity 72 and 71%, respectively]) would result in prescription of antimalarial drugs in 28-29% of the non-malaria febrile episodes, and only 49% of the true malaria cases. Thus half of the potentially life-threatening P. falciparum infections would not be treated. Although multivariate analysis identified vomiting, confirmed fever, splenomegaly and hepatomegaly as independent risk factors for a diagnosis of falciparum malaria, use of these signs to differentiate falciparum from vivax malaria, and thus to determine antimalarial treatment, was insufficiently sensitive or specific. Malaria diagnosis should be confirmed by microscopical examination of a blood slide or the use of specific dipstick tests in areas of low transmission where highly drug-resistant P. falciparum coexists with P. vivax.
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Compiled by Editors. Trop Doct 1998. [DOI: 10.1177/004947559802800114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Campbell H, Gove S. Integrated management of childhood infections and malnutrition: a global initiative. Arch Dis Child 1996; 75:468-71. [PMID: 9014596 PMCID: PMC1511817 DOI: 10.1136/adc.75.6.468] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- H Campbell
- Department of Public Health Medicine, University of Edinburgh Medeical School
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