"Test and treat" or presumptive treatment for malaria in high transmission situations? A reflection on the latest WHO guidelines

Abstract

Recent WHO guidelines recommend a universal "test and treat" strategy for malaria, mainly by use of rapid diagnostic test (RDT) in all areas. The evidence for this approach is questioned here as there is a risk of over-reliance on parasitological diagnosis in high transmission situations, which still exist. In such areas, when a patient has fever or other malaria symptoms, the presence of Plasmodium spp neither reliably confirms malaria as the cause of the fever, nor excludes the possibility of other diseases. This is because the patient may be an asymptomatic carrier of malaria parasites and suffer from another disease.To allow clinicians to perform their work adequately, local epidemiologic data are necessary. One size does not fit all. If parasite prevalence in the population is low, a diagnostic test is relevant; if the prevalence is high, the test does not provide information of any clinical usefulness, as happens with any test in medicine when the prevalence of the tested characteristic is high in the healthy population. It should also be remembered that, if in some cases anti-malarials are prescribed to parasite-negative patients, this will not increase selection pressure for drug resistance, because the parasite is not there.In high transmission situations at least, other diagnoses should be sought in all patients, irrespective of the presence of malaria parasites. For this, clinical skills (but not necessarily physicians) are irreplaceable, in order to differentiate malaria from other causes of acute fever, such as benign viral infection or potentially dangerous conditions, which can all be present with the parasite co-existing only as a "commensal" or silent undesirable guest.

Shifting from Presumptive to Test-Based Management of Malaria - Technical Basis and Implications for Malaria Control in Ghana

“…[33][34][35] However, the decision to shift from presumptive to test-based approach in managing malaria has occasioned considerable debate. 6,[36][37][38] Those who favoured the shift to test-based management of malaria argued that the factors that justified the presumptive approach were no longer valid. Malaria transmission, originally high, has been declining and affordable antimalarials were no longer effective and had been replaced with the more expensive artemisinin-based combination therapy (ACT).…”

“…They further believed that there was insufficient evidence on the safety of restricting ACT to test-positive cases and that a policy of test-based management of malaria would not necessarily lead to improvement in the management of non-malarial febrile illnesses. 38,39 In evaluating the appropriateness of implementing the shift to test-based management of malaria in Ghana, it is important to assess whether local and sub-regional evidence, supports the decline of malaria and whether the available RDTs are accurate and reliable.…”

Enfoque clínico del síndrome febril agudo en Colombia

“…A pesar del intento de la OMS por generar algoritmos diagnósticos y terapéuticos en la enfermedad febril aguda, todavía existe mucha confusión acerca del enfoque y manejo del paciente con fiebre sin foco aparente en el servicio de urgencias y, más aún, en su seguimiento hospitalario e incluso ambulatorio [1][2][3] .…”

Sensitivity and Specificity of Clear View Malaria Dual Rapid Test® among Children Attending Hospital in Sengerema District, North-Western Tanzania

“…For parasitological diagnosis, currently the WHO recommends the use of microscopy and/or rapid diagnostic tests (RDTs) for all patients with suspected malaria before initiation of treatment [1][2][3][4]. However, these recommendations have invited vigorous debate [3,5].…”