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Background Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common enzyme deficiency, prevalent in many malaria-endemic countries. G6PD-deficient individuals are susceptible to hemolysis during oxidative stress, which can occur from exposure to certain medications, including 8-aminoquinolines used to treat Plasmodium vivax malaria. Accordingly, access to point-of-care (POC) G6PD testing in Brazil is critical for safe treatment of P. vivax malaria. Methodology/Principal findings This study evaluated the performance of the semi-quantitative, POC STANDARD G6PD Test (SD Biosensor, Republic of Korea). Participants were recruited at clinics and through an enriched sample in Manaus and Porto Velho, Brazil. G6PD and hemoglobin measurements were obtained from capillary samples at the POC using the STANDARD and HemoCue 201+ (HemoCue AB, Sweden) tests. A thick blood slide was prepared for malaria microscopy. At the laboratories, the STANDARD and HemoCue tests were repeated on venous samples and a quantitative spectrophotometric G6PD reference assay was performed (Pointe Scientific, Canton, MI). G6PD was also assessed by fluorescent spot test. In Manaus, a complete blood count was performed. Samples were analyzed from 1,736 participants. In comparison to spectrophotometry, the STANDARD G6PD Test performed equivalently in determining G6PD status in venous and capillary specimens under varied operating temperatures. Using the manufacturer-recommended reference value thresholds, the test’s sensitivity at the, Author summary G6PD deficiency affects an estimated 500 million people worldwide and is prevalent in many malaria-endemic settings. People with G6PD deficiency are at risk of hemolysis when exposed to certain medications, including 8-aminoquinoline drugs used to treat Plasmodium vivax malaria. Increased access to testing for G6PD deficiency at or near the point of care is critical for expanding the safe treatment of P. vivax malaria. In this study, we aimed to evaluate the performance of a point-of-care, semi-quantitative test for G6PD deficiency, the STANDARD G6PD Test, in a malaria-endemic setting in Brazil. The test was evaluated on both capillary and venous blood samples across a broad range of operating temperatures. The findings show that the STANDARD G6PD Test performed equivalently to the reference test in its ability to diagnose G6PD deficiency at the point of care. The STANDARD G6PD Test is a promising tool to aid in detecting G6PD deficiency at the point of care in Brazil.

BackgroundGlobal progress in reducing malaria has stalled since 2015. Analysis of the situation is particularly needed in Nigeria, the country with by far the largest share of the burden, where approximately a quarter of all cases in the world are estimated to occur.MethodsWe analysed data from three nationwide surveys (Malaria Indicator Surveys in 2010 and 2015, and a National Demographic and Health Survey in 2018), with malaria parasite prevalence in children under five years of age determined by sampling from all 36 states of Nigeria, and blood slide microscopy performed in the same accredited laboratory for all samples. Changes over time were evaluated by calculating prevalence ratio (PR) values with 95% confidence intervals (CI) for each state, together with Mantel-Haenszel adjusted prevalence ratios (PRadj) for each of the six major geopolitical zones of the country.ResultsBetween 2010 and 2018 there were significant reductions in parasite prevalence in 25 states, but not in the remaining 11 states. Prevalence decreased most in southern zones of the country (South West PRadj = 0.53; South East PRadj = 0.59; South South PRadj = 0.51) and the North Central zone (PRadj = 0.36). Changes in the north were less marked, but were significant and indicated overall reductions by more than 20% (North West PRadj = 0.74; North East PRadj = 0.76). Changes in the south occurred mostly between 2010 and 2015, whereas those in the north were more gradual and most continued after 2015. Recent changes were not correlated with survey-reported variation in use of preventive measures.ConclusionReductions in malaria infection in children under five have occurred in most individual states in Nigeria since 2010, but substantial geographical variation in the timing and extent indicate challenges to be overcome to enable global malaria reduction.

Acute leukemia is a cancer-related to a bone marrow abnormality. It is more common in children and young adults. This type of leukemia generates unusual cell growth in a short period, requiring a quick start of treatment. Acute Lymphoid Leukemia (ALL) and Acute Myeloid Leukemia (AML) are the main responsible for deaths caused by this cancer. The classification of these two leukemia types on blood slide images is a vital process of and automatic system that can assist doctors in the selection of appropriate treatment. This work presents a convolutional neural networks (CNNs) architecture capable of differentiating blood slides with ALL, AML and Healthy Blood Slides (HBS). The experiments were performed using 16 datasets with 2,415 images, and the accuracy of 97.18% and a precision of 97.23% were achieved. The proposed model results were compared with the results obtained by the state of the art methods, including also based on CNNs.

In the medical field, the analysis of the blood sample of the patient is a critical task. Abnormalities in blood cells are accountable for various health issues. Red blood cells (RBCs) are one of the major components of blood. Classifying the RBC can allow us to diagnose different diseases. The traditional time consuming technique of visualizing RBC manually under the microscope is a tedious task and may lead to wrong interpretation because of the human error. The various health conditions can change the shape, texture, and size of normal RBCs. The proposed method has involved the use of image processing to classify the RBCs with the help of Convolution Neural Networks (CNN). The algorithm can extract the feature of each segmented cell image and classify it in various types as Microcytes, Elliptocytes, Stomatocytes, Macrocytes, Teardrop RBCs, Codocytes, Spherocytes, Sickel cell RBCs and Howell jolly RBCs. Classification is done with respect to the size, shape, and appearance of RBCs. The experiment was conducted on the blood slide collected from the hospital and RBC images were extracted from those blood slide images. The obtained results compared with reports obtained by the pathology lab and realized 98.5% accuracy. The developed system provides accurate and fast results due to which it may save the life of patients.

Cytological examination of peripheral white blood cells inhomogeneously distributed on a blood smear is currently limited by the low abundance and random sampling of the target cells. To address the challenges, we present a new approach to prepare and analyze concentrated blood smears by rapidly enriching white blood cells up to 32-fold with 92% recovery on average at a high throughput (1 mL/min) using a deterministic migration-based separator and by systematically analyzing a large number of the cells distributed over a blood slide using a microfabricated grid film. We anticipate that our approach will improve the clinical utility of blood smear tests, while offering the capability to detect rare cell populations.

IntroductionGlobal progress in reducing malaria has stalled since 2015. Analysis of the situation is particularly needed in Nigeria, the country with by far the largest share of the burden, where approximately a quarter of all cases in the world are estimated to occur.MethodsWe analysed data from three nationwide surveys (Malaria Indicator Surveys in 2010 and 2015 and a National Demographic and Health Survey in 2018), with malaria parasite prevalence in children under 5 years of age determined by sampling from all 36 states of Nigeria, and blood slide microscopy performed in the same accredited laboratory for all samples. Changes over time were evaluated by calculating prevalence ratio (PR) values with 95% CIs for each state, together with Mantel-Haenszel-adjusted PRs (PRadj) for each of the six major geopolitical zones of the country.ResultsBetween 2010 and 2018, there were significant reductions in parasite prevalence in 25 states, but not in the remaining 11 states. Prevalence decreased most in southern zones of the country (South West PRadj=0.53; South East PRadj=0.59; South South PRadj=0.51) and the North Central zone (PRadj=0.36). Changes in the north were less marked, but were significant and indicated overall reductions by more than 20% (North-West PRadj=0.74; North East PRadj=0.70). Changes in the south occurred mostly between 2010 and 2015, whereas those in the north were more gradual and most continued after 2015. Recent changes were not correlated with survey-reported variation in use of preventive measures.ConclusionReductions in malaria infection in children under 5 have occurred in most individual states in Nigeria since 2010, but substantial geographical variation in the timing and extent indicate challenges to be overcome to enable global malaria reduction.

The association between teething and fever has attracted considerable interest because studies have reported controversial results. These discordant results have posed a challenge in the management of fever occurring during teething. The objective of this paper is to supplement previous studies which showed association between teeth eruption and fever and highlight mismanagement of teething induced fever. A 9-month old baby girl presented with fever during teeth eruption. Despite of no malaria parasites seen on blood slide and lack of features and laboratory investigations suggestive of urinary tract infection or bacteremia, the child was treated with antimalarial drugs and prescribed antibiotics. This case study demonstrates that unrecognized teething induced fever leads to unnecessary use of anti-malarial drugs and antibiotics. We recommend paediatricians to consider teething as one of the causes of fever among children.

To assess the validity of clinical criteria, we investigated 2096 outpatients diagnosed as malaria cases by nurses at a rural health subcentre in a highly endemic area of Papua New Guinea. 73% of the children10 years old had a positive blood slide for any species of Plasmodium and 32% hador = 10,000 P. falciparum parasites per microL. For adults the frequencies were 51% and 9%, respectively. Stepwise logistic regression identified spleen size, no cough, temperature, no chest indrawing, and normal stools as significant predictors for a positive blood slide in children; no cough and normal stools predicted a positive blood slide in adults. Fever, no cough, vomiting, and enlarged spleen were significant predictors for a P. falciparum parasitaemiaor = 10,000/microL in children; in adults the only predictor was vomiting. In children the association of no cough and enlarged spleen had the best predictive value for a positive blood slide, and a temperatureor = 38 degrees C had the best predictive value for a P. falciparum parasitaemiaor = 10,000 microL. In adults, no major symptom had a good predictive value for a positive blood slide but vomiting had the best predictive value for a P. falciparum parasitaemiaor = 10,000/microL. When microscopy is not available, these findings can help in areas of high endemicity to determine which patients with a history of fever are most likely to have malaria and, more importantly, for which patients another diagnosis should be strongly considered.

I study how the misallocation of new technology to individuals, who have low ex post returns to its use, affects learning and adoption behaviour. I focus on anti-malarial treatment, which is frequently over-prescribed in many low-income country contexts where diagnostic tests are inaccessible. I show that misdiagnosis reduces average therapeutic effectiveness, because only a fraction of adopters actually have malaria, and slows the rate of social learning due to increased noise. I use data on adoption choices, the timing and duration of fever episodes, and individual blood slide confirmations of malarial status from a pilot study for a new malaria therapy in Tanzania to show that individuals whose reference groups experienced fewer misdiagnoses exhibited stronger learning effects and were more likely to adopt.

Background: Malaria is a leading cause of morbidity in Ethiopia. However, its transmission varies in both space and time, and large areas of the country are hypoendemic and epidemic-prone. The Ethiopia National Malaria Indicator Survey 2007 is a cross-sectional, nationally-representative household survey. The objective of the analyses presented here were to use the survey's data to identify factors associated with anemia presence in children under 6 years of age (U6); specifically, investigate the association between malaria and anemia; and discuss using anemia as a malaria proxy biomarker in the Ethiopian hypo-endemic transmission setting. Methods: The survey sampled 4185 households in 347 enumeration areas ≤2500 m above sea level. Primary outcome was increasing anemia severity in sampled children: no anemia (Hb: ≥11g/dl); mild anemia (Hb: ≥8g/dl and

In this work an image processing system was developed to identify malaria parasites in thin blood smears and to classify them into one of the four different species of malaria. Many techniques were implemented in the preprocessing stage to enhance the images. In the first part of the system morphological processing is applied to extract the Red Blood Cells (RBC) from blood images. The developed algorithm picks the suspicious regions and detects the parasites in the images including the overlapped cells. Accordingly, the RBCs are classified into infected and non-infected cells and the number of RBCs in each image is calculated. The second part of the system uses the Normalized Cross-Correlation function to classify the parasite into one of the four species namely, Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale. Compared to manual results, the system achieved 95 % accuracy for detection and counting of RBCs and 100% for detection and classifying the parasite into one of its four types.

OBJECTIVE In Africa antimalarials are often prescribed when malaria is unlikely, a problem that is becoming critical as more expensive antimalarials replace established drugs. However, little is known about what drives the overuse of antimalarials. We conducted this study to explore to what extent current prescribing behaviour in hospitals is driven by patient demand. METHODS Consultations were observed followed by exit interviews with patients or caretakers. Five district hospitals where microscopy was routinely available were selected in areas of low (n = 3) and high (n = 2) malaria transmission in north-eastern Tanzania. All outpatient consultations during the study period were observed (n = 669). Those sent for a malaria blood slide or treated with antimalarials presumptively were interviewed (n = 326). At the end of the study, clinicians were interviewed for their opinions on the use of antimalarials. Findings Patients were not observed to demand antimalarials from clinicians, but occasionally asked for a malaria slide. Patient satisfaction on exit was similar between those prescribed antimalarials and those not prescribed antimalarials, but more patients or carers expressed satisfaction when the patient had been tested than when not. Clinicians rarely reported perceiving patient demand for antimalarials and asserted that such demand for medication would not affect their prescribing behaviour. CONCLUSIONS Patient demand was not found to be driving the over-prescription of antimalarials found in the hospitals in our setting. To the contrary, the involvement of patients may provide an opportunity to improve prescribing practice if their expectations for testing and treatment in line with test results can be effectively communicated to clinicians.

Background: Malaria diagnosis continues to be the foremost among the challenge in malaria control strategies in Sub-Saharan countries including Tanzania. The World Health Organization changed malaria treatment Guidelines in 2010 to restrict the use of antimalarial drugs to parasitologically confirmed malaria cases in response to the overuse of antimalarial drugs. Malaria rapid diagnostic tests (mRDTs) are presented as a mean to implement the new guidelines for malaria parasitologically confirmed cases prior to initiating antimalarial drug therapy for mRDT positive patients. Methods: A hospital-based cross-sectional study among patients with fever and malaria-like symptoms was done between May and June, 2014 in Korogwe district hospital in a convenient manner. Data were cleaned and analysed in Epi-Info version 3.5.4 computer software, Chi-square test was used to compare proportions between two groups with P-value set at 0.05. Results: Results revealed that sensitivity, specificity, positive predictive value and negative predictive value of mRDT at 95% CI was 97.6%, 97.4%, 91.0% and 99.3% respectively. All patients with positive mRDT were treated with antimalarial drugs, while patients with negative mRDT results were treated with either antimalarial (P-value = 0.001) or antibiotics (P-value = 0.005) at 95% CI. The results of patients with negative mRDT results were less likely to be further investigated at 95% CI (P-value = 1.000). Conclusion: The mRDT had good sensitivity and specificity if compared with blood slide microscopy. Clinicians adhered to the 2010 World Health Organization guidelines adopted by the National Malaria Control Programme for patients with positive mRDT result; however, they did not adhere to malaria diagnosis and management guidelines in case of negative mRDT results.

Millions of white blood cells are manually classified in laboratories using microscopes, a painstaking and subjective task. A trained medical technician takes about 15min to evaluate and count 100 cells for each blood slide, a time consuming and susceptible to error procedure. Leukocyte shape is usually insufficient to differentiate even among normal types since it varies widely. The current paper addresses the pattern recognition problem of blood image analysis and how textural information can improve differentiation among leukocytes. Cooccurrence probabilities can be used as a measure of gray scale image texture, a statistical method for characterizing the spatial organization of the gray-tones. We calculate five textural attributes based on gray level cooccurrence matrices (GLCM) as energy, entropy, inertia and local homogeneity, testing these features in leukocyte recognition. Several parameters must be estimated for obtaining GLCM, therefore we implement datamining algorithms for estimating suitable scales. Feature selection methods are also applied to define the most discriminative attributes for describing the cellular patterns. Experimental results show that texture parameters are essential to differentiate among the five types of normal leukocytes and chronic lymphocytic leukemia, evidencing the importance of biological aspects regarded by hematologists as nuclear chromatin and cytoplasmical granularity.

To examine the role of disgust in blood-injection fear and faintness, 79 individuals high and low in disgust and distressed either more by blood or injections were exposed to both a blood slide and a needle slide. Self-reported faintness and systolic and diastolic blood pressure were measured. High disgust individuals reported more faintness to both slides, but those who were more distressed by blood reported more faintness to the blood slide and those who were more distressed by needles reported more fear to the needle slide. Both systolic and diastolic blood pressure assessments manifested a diphasic response. The diphasic response pattern was most evident among the high disgust subjects, who were more distressed by blood than injections. Results are discussed in terms of the relevance of disgust in the etiology of fear and faintness in blood-injury phobia.

Some Ministries of Health in Africa plan to make blood slide microscopy available in peripheral health centers to improve malaria diagnosis over the current practice, which relies solely on clinical findings. To assess whether microscopy improves the management of febrile persons in health centers, we prospectively reviewed medical records of all outpatients visiting six health centers with laboratories in Zambia during a 2-3-day period. Staff interviews and a blinded review of a series of blood slides from each facility by two expert microscopists were also conducted. Of 1,442 outpatients, 655 (45%) reported fevers or had a temperature > or = 37.5 degrees C. Blood slide microscopy was ordered in 28-93% of patients with fever (mean = 46%). Eighty-eight (35%) patients without parasitemia were prescribed an antimalarial drug. Antimalarial drugs were prescribed with equal frequency to those who were referred for a blood slide (56%) and those not referred (58%). The sensitivity of microscopy was 88% and the specificity was 91%. Use of malaria microscopy varied widely, indicating that clinicians are not using standard criteria for ordering this test. Although diagnosis by microscopy was generally accurate, it appeared to have had little impact on the treatment of persons with fever. Guidelines for using blood slide microscopy are needed and prescription of antimalarial drugs should be discouraged when slide results are negative.

Objective: To determine if use of basic laboratory tests improves diagnosis and treatment outcomes in outpatients attending rural primary health care facilities. Setting: Six rural health centres in Kenya. Design: Cross-sectional study to observe change in diagnosis and treatment made by clinical officers after laboratory testing in outpatients attending six rural health centres in Kenya. Subject: The diagnosis and treatment of 1134 patients attending outpatient services in six rural health centres were compared before and after basic laboratory testing. Essential clinical diagnostic equipment and laboratory tests were established at each health centre. Clinical officers and laboratory technicians received on-site refresher training in good diagnostic practices and laboratory procedures before the study began. Results: Laboratory tests were ordered on 704 (62.1%) patients. Diagnosis and treatment were changed in 45% of tested patients who returned with laboratory results (21% of all patients attending the clinics). 166 (23.5%) patients did not return to the clinician for a final diagnosis and management decision after laboratory testing. Blood slide examination for malaria parasites, wet preparations, urine microscopy and stool microscopy resulted in most changes to diagnosis. There was no significant change in drug costs after laboratory testing. The greatest changes in numbers of recorded diseases following laboratory testing was for intestinal worms (53%) and malaria (21%). Conclusion: Effective use of basic laboratory tests at primary health care level significantly improves diagnosis and patient treatment. Use of laboratory testing can be readily incorporated into routine clinical practice. On-site refresher training is an effective means of improving the quality of patient care and communication between clinical and laboratory staff.

The mathematical morphology technique, granulometry, is used to create the pattern spectrum of a malarial blood slide image. From this, the red blood cell size can be evaluated, making subsequent processing scale-invariant.

There is always a need for the development of systems to provide assistance to physicians and to relieve the physician of drudgery or repetitive work. So, more systems for automatic processing of medical images are being developed. In case of malaria diagnosis, the usual method of estimating the parasitaemia is to take number of slides and examine them manually through a microscope and count parasitaemia which is not only a time consuming task and but also prone to human error. This paper discuss the development of a system to automatically digitise the malaria infected blood slides and process them to produce information such as parasitaemia, infected and total red blood cell count as required by the physicians and the field workers. The methodology for the blood slide image processing is developed using mathematical morphology. Because of its basis on analysis of shape and size and it is well suited for this application. This paper presents various steps involved and procedures evolved for the task of developing such a system. (6 pages)

This paper presents the personal experiences of Tabitha Mwangi a Kenyan woman who was infected with malaria. It was noted that the initial symptoms she felt were a feeling of chilliness and vomiting. Examination of blood caused excitement in the laboratory due to the number of parasites found. Results revealed that she was positive of malarial infection. Unfortunately Mwangi was infected again while working in a malaria research institute. After hundreds of blood slide examinations she was diagnosed to have malaria and was prescribed to take fansidar (sulfadoxine and pyrimethamine) and paracetamol. Symptoms experienced include profuse sweating dizziness throbbing headache and high fever. Her condition was alleviated after days of medication.

Determination of the percentage of cells in clumps on a stained smear of human peripheral blood porvided a useful, accurate technique for measuring cell adhesiveness. Smears of human peripheral blood drawn with EDTA were prepared on a blood slide centrifuge, stained, and examined under a light microscope. Statistical analysis showed that the method resulted in a Poisson distribution of particles on the slide, where a particle was considered to be a simple cell, or two or more cells which appeared to be touching, Analysis of the distributions of erythrocytes and leukocytes showed that clumps were formed before the cells were deposited on the slide. When adhesiveness of erythrocytes or leukocytes was increased by incubation with antiserum to the corresponding cell type, the percentage of that cell type in clumps increased proportionately, Preliminary results using the method showed that normal human donors had similar to 1% of their erythrocytes and 1- 5% of their leukocytes in clumps. In chronic myelocytic leukemia, as many as 60% of the leukocytes were in clumps.

3,373 children in the age group of 0 to 14 years were examined for malaria. Out of this 489 (14.4%) children had malarial parasite in their blood. Of these positive cases, 90.59% had plasmodium falciparum infection. The A.P.I. was found to be 21.59 per thousand, whereas the Infant Parasite Rate was 6.80%. As malaria due toP. falciparum is quite fatal, steps to eradicate this disease is discussed.

In the autumn of 1913 Major Kenrick, I. M. S., kindly sent me, from Pachmari, Central Provinces, India, a blood slide from a native child, containing numerous malaria parasites. On examining these, which I at first took to be malignant tertian parasites, the suspicion arose in my mind that there was something peculiar about their appearance. I happened just previously to have been studying a blood slide from Rhodesia, containing very numerous malignant tertian parasites. The peculiarity of the Indian parasite, as far as I could at first define it, was that it was an irregular parasite as compared with the regular, almost monotonous, contour of the “rings” of the malignant tertian parasite ( Plasmodium falciparum ). I proceeded then to study the Indian parasite more carefully; and, after-daily observations for many weeks of it, and of control malignant tertian parasites from various sources, I came definitely to the conclusion that it was unlike any malignant tertian parasite that I had ever seen or that I could find figured in the text-books or journals. I also considered carefully the possibility of its being the simple tertian parasite, but to this point I shall return later. During this study, in order to fix my impressions, I drew 150 consecutive parasites from the Indian slide and the Rhodesian slide respectively, as the former appeared in the field of view of an ocular so restricted by placing a diaphragm in it that only half a dozen red cells were visible in the field at a time, thus effectively preventing any selection on my part. I reproduce as pen-and-ink drawings 35 of each series taken at random, as they show very well in a general way the different aspect of the two parasites. For the same purpose I also drew a number of young simple tertian parasites. I now proceed to define as far as possible in detail the peculiarities of this parasite.

Summary We describe a 32-year-old Bangladeshi male presenting with severe malaria caused by a mono-infection with Plasmodium malariae. Rosetting of infected and uninfected erythrocytes, a putative virulence factor in falciparum malaria, was observed in the blood slide. Severe disease caused by P. malariae is extremely rare. The patient made a rapid recovery with intravenous quinine treatment.

Manual skills are all those skills which involve use of the hands. For example, giving an injection, palpating an abdomen, focusing a microscope, measuring blood pressure (BP), preparing a blood slide, etc., are all manual skills.