Appropriate use

Best practices for introducing and using rapid diagnostic tests

In order for rapid diagnostic tests (RDTs) to be utilized effectively, resources must be applied to ensure the quality of each test from the time it is manufactured until it is used. It is important to establish an implementation plan which is overseen by a national regulatory body with sufficient authority to ensure that all aspects of the plan are carried out.

There are a number of comprehensive handbooks published by the World Health Organization (WHO) that describe how to roll-out specific RDT programs (please see “more information” at the bottom of this page). Here we provide an overview of the key elements of RDT implementation plans.

Program coordination

Careful planning and coordination are critical to the successful implementation of an RDT program. Program coordinators should be put in place to ensure all aspects of the program are successfully fulfilled. Before establishing the program, the role RDTs will play in diagnosis and case management should be clearly identified and a plan for implementation should be established. Key elements of an implementation plan are: procurement guidelines, health worker training and monitoring, “cool chain” for transport and storage, quality assurance (QA) testing, and clear guidelines of how tests should be used in the clinical setting.

Additionally, adequate supplies of RDT and treatment should be made available to ensure an effective intervention. Accordingly, sufficient budget allocations must be made to each of these activities.

Procurement

There are many companies to choose from when considering RDT. Before procuring large quantities of test kits, it is wise to acquire and test three or four different test kits. Key information to help compare kits is as follows:

  • Product performance (sensitivity, specificity, etc.).
  • Ease of use.
  • Product cost.
  • Evidence of sound product performance in the field.
  • Availability of sample products for pre-purchase assessment.
  • Temperature stability data: Real-time stability for the product and accelerated stability for the purchased lot.
  • Availability of technical support.
  • Terms of replacement for products which fail initial QA tests.
  • Long-term viability of the manufacturer and adequate manufacturing capacity (to ensure continuous supply).
  • Packaging appropriate to the rate of use of tests. Seek to minimize storage in poor conditions and limit need to split boxes for in-country distribution.
  • Evidence of good manufacturing practice (CE Mark or International Organization for Standardization [ISO] certification).

Storage and distribution

High temperature and humidity have been identified as key contributors to a decline in sensitivity of RDTs over time. RDTs are packaged to minimize exposure to humidity and it is important to ensure that the packaging is not damaged during transport and storage. Most manufacturers recommend storage between 2°C and 30°C. The development of a “cool chain” capable of maintaining temperatures within this range during transport and storage is critical to protect RDTs.

The following recommendations were published in the WHO publication, The Use of Malaria Rapid Diagnostic Tests and represent a good framework:

Shipping from manufacturers

  • Before shipping: The manufacturer contacts consignees with details of airway bill numbers, airline carrier, flight number, numbers of containers, expected arrival time. These details should be sent by email and followed up by fax.
  • The shipper (air carrier) is notified of temperature storage requirements by the manufacturer in writing and by clear markings on cartons and related documents. (Stowage of the shipment close to the skin of some aircraft may result in freezing.)
  • The manufacturer initiates shipment only when the consignee confirms the shipping notification is received.
  • Consignees then arrange to have customs agents or other personnel on site to receive materials. Shipments are moved immediately to moderate temperature storage (less than 30°C if possible). Avoid leaving materials on airport tarmacs, in customs sheds, or in vehicles.

Ground transportation

  • Ground transportation during any stage of delivery is carried out without delay and with attention to ambient temperature while the vehicle is moving and if parked. Avoid leaving RDTs in vehicles parked in the sun.

Storage

  • Storage at central and final field facilities should be within the manufacturer's specifications (usually ≤30°C).
  • Maximize the time RDTs are stored in centralized, controlled conditions; minimize uncontrolled storage in remote areas. Smaller box sizes may help achieve this.
  • Select a cool peripheral storage location; thatch roofing may be cooler than iron, maximize shade, consider evaporative cooling cabinets.

Quality assurance (QA) monitoring

It is imperative to monitor any diagnostic testing system to ensure accuracy and identify opportunities for improvement. QA monitoring extends from the choice of manufacturer all the way to the use of the test by the end user. QA monitoring activities should include:

  • Ensuring good manufacturing practice by vendors
  • Lot testing of purchased tests
  • Testing the stability of tests under normal storage conditions for your program
  • Monitoring storage and transport systems
  • Implementing sound training and certification systems for those performing tests
  • Monitoring test performance in field settings

Strong QA monitoring requires sponsorship and support from the highest levels of the diagnostic testing program and sufficient resources to carry out the necessary activities.

The specifics of QA monitoring vary from test to test. WHO has published comprehensive manuals for implementing RDT programs that cover QA monitoring (see “more information” below).

Training

Training of key staff is critical to successful implementation of an RDT program. Comprehensive training manuals and job aids are available for the use of specific RDTs such as malaria and HIV (see “more information” below). These manuals focus on training for staff at the village or clinic level and focus on how to take a finger-prick blood sample, perform an RDT, and read results. Materials can be adapted to suit the needs of training programs for specific countries.

Links to more information