English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Despite advances in treatment and diagnosis, malaria continues to cause a significant number of deaths, particularly in African children.1 Optimized diagnostic and follow-up testing is required for appropriate treatment and eventual eradication of malarial disease in sub-Saharan Africa. Microscopy is compared to rapid diagnostic testing (RDT) for use in a low-resource setting. introduction Malaria is a curable disease caused by the infection of red blood cells with the parasite Plasmodium, a protozoan transmitted between carriers via bites from infected Anopheles mosquitos. According to the World Health Organization (WHO), malaria is responsible for between 473 000 and 789 000 deaths worldwide per year.1 Most deaths occur in children living in Africa, though elderly individuals, immunocompromised pregnant women and previously unexposed travellers are also at increased risk of experiencing severe disease in endemic areas.1,2 Chronic infection with the parasite results in partial immunity; individuals infected for the first time are the most vulnerable to complications of the disease, whereas those with chronic infections often become asymptomatic carriers.1 Malarial illness typically presents with fever, chills and vomiting, making its differential diagnosis difficult , and may result in severe complications or death if left untreated.2 Common complications observed in children include anemia, metabolic acidosis and cerebral malaria, whereas adults with severe disease are more likely to develop multi-organ failure.1 Childhood infection with malarial parasites has also been associated with increased prevalence of chronic anemia and status epilepticus in Africa.3,4 Thus, access to accurate and reliable diagnostic technology could help to reduce the burden of malaria-associated deaths and complications.1-4 Further, lack of accessibility and incorrect use of diagnostic technology has resulted in overprescription of antimalarial drugs.2 Widespread use of artemisinin monotherapy, rather then the gold standard artemisinin combination therapy (ACT), and discontinuation of antimalarial drugs based on symptom resolution rather then clearance of infection have contributed to the development of artemisinin-resistant strains in some geographical areas.5 The widespread dissemination of resistant strains could be devastating as methods of identifying and treating drug-resistant malarial strains have not yet been developed.5 Improved accessibility to accurate malaria diagnosis in sub-Saharan Africa is necessary for elimination of malaria as it ensures that individuals presenting with fever are treated appropriately, thus reducing overprescription and transmission to more vulnerable populations. Though several tests exist for the diagnosis of malaria, there are many challenges to implementing them in sub-Saharan Africa. Previous efforts to eliminate malaria in this setting have failed despite the availability of diagnostic testing. Possible barriers to implementation may include poor infrastructure maintenance, lack of trained microscopy personnel, expiration or degradation of testing materials caused by heat and humidity, high financial costs and lack of quality control measures. In order to increase accessibility to testing in this setting, tests need to be sensitive and specific, but also easy to use, able to provide results rapidly and tolerant of poor storage conditions. This article will discuss the benefits and drawbacks of two commonly used technologies: microscopy and rapid diagnostic testing (RDT). microscopy Microscopy with Giemsa staining is considered the gold standard for diagnosis of malaria.6 Several different methods of microscopy are currently available. Thick blood smear microscopy examines a larger volume of blood and is thus useful for determining whether the parasite is present.6 Thin blood smear microscopy is less sensitive because a smaller volume of blood is used, but is more effective at determining parasite species: as such, it gives valuable information about a patient’s risk for complications and the appropriate course of action.6 Microscopy performed in a clinical setting with skilled personnel is the most sensitive form of testing available for malaria diagnosis; detection of parasitemia can occur at concentrations of 4 to 20 parasites per μL.6 However, this level of sensitivity is achievable only by experienced microscopists with adequate supplies and training.7,8 Field studies in Africa have demonstrated that parasitemia levels as high as 50 to 100 parasites per μL may be required for detection of malaria in local laboratory settings.7,8 Several studies conducted in febrile patients diagnosed with malaria have found poor agreement between regular microscopy and research microscopy and suggest that antimalarial overprescription rates may approach 50% in some areas.9 Sensitivity and specificity of regular microscopy was also found to vary considerably among different facilities, suggesting that the efficacy of microscopy is dependent upon the expertise of the microscopist.9,10 Several studies have been conducted in an African setting comparing routine microscopy to research microscopy. Results suggest that routine microscopy performs poorly in low-resource settings, with one trial finding that positive tests were confirmed by research microscopy only 43% of the time and the other, a study conducted in Dar es Salaam, finding only a 47% specificity for routine microscopy.2,10 It is therefore not surprising that a survey conduct-

A comparison of the efficacy of microscopy versus rapid diagnostic testing in sub-Saharan Africa