Considerations for selecting a rapid diagnostic test (RDT) product include:

• plasmodium species to be detected (Plasmodium falciparum only and/or non-falciparum species) and target antigens;
• diagnostic performance assessed during the laboratory evaluation component of the WHO Prequalification process (panel detection score, false positive rate and invalid rate);
• shelf life and temperature stability in intended conditions of storage and use;
• ease of use, including test format and blood transfer device options;
• requirement for post-treatment testing of patients;
• cost (including transport, training and quality control).

For procurement, WHO recommends that all RDTs be WHO-prequalified. A full list can be found on the WHO prequalification page related to Prequalified In Vitro Diagnostic products. All products that are WHO-prequalified meet the required minimum performance criteria and are considered acceptable for procurement and to diagnose clinical malaria. Products which exceed these minimum performance criteria are not expected to have any significant clinical benefit  over those that just meet these criteria.  All WHO prequalified malaria RDTs have a public report available that summarizes the assessment carried out, as well as any inspection of the manufacturing site(s) that manufacture that product.

In the case that no appropriate WHO-prequalified test is available (or there is very limited choice) to meet procurement needs, i.e. settings with a high prevalence (≥5%) of pfhrp2/3 gene deletions causing negative HRP2-RDT results, all procured RDTs should meet the following minimum requirements:

• i) ISO 13485 certified, 
• ii) Product is in the WHO prequalification pipeline and has passed the laboratory evaluation achieving: 
• at least a 75% "panel detection score" for low parasite density samples (200 p/µL) from the product testing evaluation panel for the detection of  P. falciparum (HRP2 expressing and nonHRP2 expressing panels) and, if applicable for P. vivax;
• a false positive rate of less than 10%; and
• fewer than 5% invalid tests.

NB. The panel detection score (PDS) is not the same as "sensitivity" which is measured in a real population where there is a variable mix of high and low density infections. The PDS at 200p/µL rather reflects how the test can be expected to perform when challenged at the lower limits of clinically significant parasitemia.

It is recommended that RDTs with high thermal stability be selected for use in areas with very high ambient temperature, ideally 40–45 °C.

Special considerations for case management in areas with high prevalence of pfhrp2/3 gene deletions

In areas where ≥5% of P. falciparum cases are missed due to negative RDTs resulting from pfhrp2/3 deletions, WHO recommends a shift away from exclusive HRP2-based RDTs. However, alternatives are limited. Therefore, currently WHO accepts procurement of non WHO-prequalified for detection of P. falciparum that are pan-LDH-only RDTs or combination of HRP2 and pf-LDH  and to detect and discriminate falciparum from P. vivax or non-Pf infections combination RDTs targeting Pf-pLDH antigens with pan-LDH or pv-LDH +/-HRP2, if the following conditions are met:

• valid ISO 13485:2003, submission of application for WHO prequalification, and
• acceptable diagnostic performance against both HRP2 expressing and HRP2 non-expressing at 200p/µL (pfhrp2/3 single or double deletions) based on the most recent WHO laboratory assessment, performed at the United States Centers for Disease Control and Prevention.

Data on performance against non-HRP2 expressing parasite panels is currently limited and varies depending on single or double deletions of pfhrp2 and pfhrp3 due to the cross reactivity of HRP3 with HRP2 test lines. Efforts are underway to expand this panels in terms of their number and diversity and in the meantime using current knowledge to inform procurement and predict RDT performance in the field requires a detailed understanding of the local epidemiology and should be done in consultation with experts. 

The table below summarizes the alternative testing options for areas were ≥5% of P. falciparum cases are missed by HRP2-RDTs due to pfhrp2/3 deletions. 

List of currently eligible products

WHO-prequalified

There are currently no WHO -prequalified products meeting requirements.

Non WHO-prequalified tests meeting critical criteria ^a

^a Valid ISO 13485:2003, submission of application for WHO prequalification, and acceptable diagnostic performance against both HRP2 expressing and HRP2 non-expressing at 200p/µL (pfhrp2/3 single or double deletions) based on the most recent WHO laboratory assessment, performed at the United States Centers for Disease Control and Prevention.

Additional stepwise procurement considerations for malaria RDTs 

Step 1 – Estimating needs

Estimate the number of malaria cases and RDT requirements for back-up stocks at different levels of the supply chain. Estimate the order size and frequency of deliveries to maintain adequate stocks to meet requirements, avoiding stock-outs and over-stocking (with risk of unused, expired RDTs).
Responsible entity: National malaria control programme, quantification and forecasting team, laboratory department, procurement department

Step 2 – Budgeting and budget component

Consider all budget requirements to obtain quality-assured RDTs, including operating expenses (distribution, supply management, information and communication, training, supervision, quality assurance, quality control, monitoring and reporting) and not merely the cost of procuring the RDTs.
Responsible entity: National malaria control programme

Step 3 – Defining technical specifications

Provide comprehensive, detailed specifications for the selected product, so that the manufacturer receives a clear indication of all RDT requirements for the clinical user.
Responsible entity: National malaria control programme

Step 4 – Procurement method and tender documents

Assemble tender specifications and technical, commercial and quality evaluation tender criteria documentation from the preceding steps, conforming with the administrative and financial requirements of the agency funding the procurement of RDTs (as appropriate), and publish the tender according to the procurement method selected.
Responsible entity: Procurement unit team members, with input on technical and quality aspects from national malaria control programme

Step 5 – Inviting tenders

Invite requests for proposals from manufacturers that have been independently assessed as having the competence and the capacity to meet the procurement requirements. The independent assessment should include verification of WHO prequalification listing (or alignment with diagnostic performance requirements in exceptional cases); real-time temperature stability data on the product; long-term viability of manufacturer (to ensure continuity of supply); availability of product support; agreement for replacement of products which fail agreed quality control procedures; and box sizes appropriate to the rate of use of tests in the intended area to minimize storage time in poor conditions and limit the need to split boxes.
Responsible entity: Procurement management unit in consultation with regulatory authority

Step 6 – Evaluating bids and awarding contracts

Thoroughly check the specifications of the product offered against the requirements submitted in the tender documents. Then, check the supplier criteria and documentation in the product dossier. Contracts may be awarded to suppliers that meet the criteria, with clear indications of terms and conditions for deliveries and liability.
Responsible entity: Procurement management unit and national malaria control programme

Step 7 – Quality assurance in procurement

Ensure the quality of the procurement programme, including appropriate quality control, such as lot testing, through WHO-recognized laboratories.
Responsible entity: Procurement management unit

Step 8 – Quality control by lot testing

As the performance of individual products is likely to vary between lots over time, WHO recommends that all RDT production lots be checked, either before or, ideally, after shipment, and in response to concerns/complaints post-deployment, at a lot-testing centre that collaborates with the WHO, as part of good procurement practice. Currently WHO support this service free of charge at the Research Institute for Tropical Medicine in the Philippines. Full information on WHO-recommended procedures for RDT lot testing are available on the WHO website as well as compiled results of lots evaluated for the period 2007–2020.

Historically, WHO has commissioned independent, external quality laboratory assessments of the National Institute of Malaria Research (NIMR), New Delhi, India and the ANDI Centre of Excellence for Malaria Diagnosis, University of Lagos, Nigeria and these laboratories have been found to be compliant with WHO malaria RDT lot testing standard operating procedures. These laboratories conduct lot verification for RDT batches imported into their respective countries and should be contacted for information regarding their ongoing compliance with WHO procedures and availability of lot testing services (India: shbira@gmail.com; Nigeria: andimalariacentre@unilag.edu.ng).

In 2018, the WHO-FIND RDT Evaluation Programme Steering Committee concluded that  the HRP2 or pLDH recombinant antigen panels developed by FIND and commercial partners could not be reliably used for malaria RDT lot testing purposes as some critical knowledge gaps on the panel characteristics remain. Also, data analysis showed that the lot testing procedure based on recombinant panels is not fully equivalent to the current one based on clinical samples.
Responsible entity: Procurement management unit, quality assurance officer

Step 9 – Transport, port clearance and receipt

Air or sea port clearance has many potential pitfalls and possible delays; careful planning is needed to avoid exposure of RDTs to high temperatures, with concerted preparation for handling at receipt, storage and distribution. Verification of the delivered product at receipt is recommended.
Responsible entity: Procurement management unit, supply chain manager

Step 10 – Monitoring

Supplier performance should be assessed in relation to the responsibilities in supply, which should be described in detail in the tender documents and contracts so that the relationship between the supplier and the manufacturer and their liabilities are clear. Regular system audits and open communication channels are particularly important in this respect.
Responsible entity: Procurement management unit and national malaria control programme

Step 11 – Continuous improvement

Effective use of a comprehensive quality management system for information on deficiencies of any kind can result in steady, continuous improvement.
Responsible entity: Procurement management unit and national malaria control programme