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Background The emergence and spread of Plasmodium falciparum parasites that lack HRP2/3 proteins and the resulting decreased utility of HRP2-based malaria rapid diagnostic tests (RDTs) prompted the World Health Organization and other global health stakeholders to prioritize the discovery of novel diagnostic biomarkers for malaria. Methods To address this pressing need, we adopted a dual, systematic approach by conducting a systematic review of the literature for publications on diagnostic biomarkers for uncomplicated malaria and a systematic in silico analysis of P. falciparum proteomics data for Plasmodium proteins with favorable diagnostic features. Results Our complementary analyses led us to 2 novel malaria diagnostic biomarkers compatible for use in an RDT format: glyceraldehyde 3-phosphate dehydrogenase and dihydrofolate reductase-thymidylate synthase. Conclusions Overall, our results pave the way for the development of next-generation malaria RDTs based on new antigens by identifying 2 lead candidates with favorable diagnostic features and partially de-risked product development prospects. [ABSTRACT FROM AUTHOR]

Background: Microscopic examination is commonly used for malaria diagnosis in the field. However, the lack of well-trained microscopists in malaria-endemic areas impacted the most by the disease is a severe problem. Besides, the examination process is time-consuming and prone to human error. Automated diagnostic systems based on machine learning offer great potential to overcome these problems. This study aims to evaluate Malaria Screener, a smartphone-based application for malaria diagnosis., Methods: A total of 190 patients were recruited at two sites in rural areas near Khartoum, Sudan. The Malaria Screener mobile application was deployed to screen Giemsa-stained blood smears. Both expert microscopy and nested PCR were performed to use as reference standards. First, Malaria Screener was evaluated using the two reference standards. Then, during post-study experiments, the evaluation was repeated for a newly developed algorithm, PlasmodiumVF-Net., Results: Malaria Screener reached 74.1% (95% CI 63.5-83.0) accuracy in detecting Plasmodium falciparum malaria using expert microscopy as the reference after a threshold calibration. It reached 71.8% (95% CI 61.0-81.0) accuracy when compared with PCR. The achieved accuracies meet the WHO Level 3 requirement for parasite detection. The processing time for each smear varies from 5 to 15 min, depending on the concentration of white blood cells (WBCs). In the post-study experiment, Malaria Screener reached 91.8% (95% CI 83.8-96.6) accuracy when patient-level results were calculated with a different method. This accuracy meets the WHO Level 1 requirement for parasite detection. In addition, PlasmodiumVF-Net, a newly developed algorithm, reached 83.1% (95% CI 77.0-88.1) accuracy when compared with expert microscopy and 81.0% (95% CI 74.6-86.3) accuracy when compared with PCR, reaching the WHO Level 2 requirement for detecting both Plasmodium falciparum and Plasmodium vivax malaria, without using the testing sites data for training or calibration. Results reported for both Malaria Screener and PlasmodiumVF-Net used thick smears for diagnosis. In this paper, both systems were not assessed in species identification and parasite counting, which are still under development., Conclusion: Malaria Screener showed the potential to be deployed in resource-limited areas to facilitate routine malaria screening. It is the first smartphone-based system for malaria diagnosis evaluated on the patient-level in a natural field environment. Thus, the results in the field reported here can serve as a reference for future studies., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background: One of the malaria vulnerable groups is people living with HIV. This study investigated knowledge, attitude and practices (KAP) towards malaria in people living with HIV attending anti-retroviral therapy (ART) clinics in rural and urban Ghana., Methods: In this descriptive cross-sectional study patients attending the ART clinics in Atibie (rural area) and Accra (urban area) were interviewed on their knowledge, attitude and practices regarding malaria. Finger-prick capillary blood was tested for Plasmodium spp. with rapid diagnostic tests. Multivariate regression analysis was used to determine the influence of KAP on malaria prevalence., Results: Parasitemia was generally more frequent among HIV positive individuals in the rural area (29/116; 25%) in the rural area than in the urban area (35/350; 10%). Inaccurate knowledge of cause of malaria and prevention methods were associated with increased odds of malaria parasitemia; [OR = 1.51 (CI: 1.29-5.12); p < .05] and [OR = 2.59 (CI: 2.53-4.75); p < .05], respectively. There were disparities in socio-economic factors. For instance, low level of education was higher in the rural area (45/116; 38.8%) compared to the urban area (121/350; 34.6%)., Conclusions: Malaria control efforts may yield further results when the knowledge and socio-economic gap between rural and urban areas is closed., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objectives: This observational study recorded the malaria and sickle cell disease (SCD) profile of people living with HIV/AIDS (PLHA) and determined whether prophylactic co-trimoxazole (CTX) and the haemoglobin S (Hb S) allele influenced malaria episodes., Methods: Sickling status, malaria episodes, and HIV type, as well as other data, were extracted retrospectively from the clinical records of 1001 patients attending the antiretroviral therapy clinic at Ridge Regional Hospital in Accra, Ghana between 2010 and 2015. Finger-prick capillary blood of returning patients (n=501) was tested for the haemoglobin (Hb) level and malaria, after information on malaria prevention methods was obtained through the administration of a questionnaire., Results: The use of insecticide-treated mosquito nets was low (22.8%). CTX prophylaxis showed no significant influence on the overall number of malaria episodes from 2010 to 2015; however, it did show a statistically significant relationship (p=0.026) with the time elapsed since the last malaria episode. Even though 19% of participants possessed Hb S, it had no influence on malaria episodes., Conclusions: Hb S did not influence malaria in PLHA. Further studies in Hb SS and Hb SC are needed, as there are suggestions of increased frequency and severity of malaria. The impact of CTX prophylaxis on this cohort will be insightful., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)