WHO recommends prompt malaria diagnosis either by microscopy or rapid diagnostic tests (RDTs) for all patients with suspected malaria before they are given treatment. Early and accurate diagnosis is essential both for effective management of malaria and other febrile illnesses and for strong malaria surveillance.

To strengthen the capacities of national malaria programmes on the use of microscopy and RDTs, WHO has elaborated standard operating procedures, training and operational manuals as well as videos and photo libraries. WHO has also developed surveillance protocols, mapping tools and an international network of laboratories to support molecular studies and gene sequencing and replace HRP2-detecting RDTs in areas where gene deletion is affecting their reliability.

To promote quality assurance of malaria microscopy, WHO coordinates the external competence assessment of malaria microscopists (ECAMM), involving participants from 63 malaria endemic countries in the WHO Western Pacific, South-East Asia, African and Eastern Mediterranean regions.

In 2008, WHO and the Foundation for Innovative New Diagnostics (FIND) established an international quality assurance scheme in collaboration with the US Centers for Disease Prevention and Control to generate recommended criteria for selecting malaria RDTs. Since 2019, WHO prequalification of malaria RDTs is required for procurement by WHO and by several international agencies, based on laboratory performance, dossier review and inspection of the manufacturing facilities.