Step 4.1 – Review forecasting, ordering and distribution procedures
Step 4.2 – Develop procedures to monitor reagent quality and shelf life
Step 4.1 – Review forecasting, ordering and distribution procedures
Uninterrupted availability of reagents and disposables at the testing site is essential to ensure that technical capacity is built in the early stages of implementation (avoiding long delays between training and availability of reagents and disposables), and to ensure consistent service during routine use. The following measures will be required to ensure uninterrupted supply of reagents and disposables:
- ensuring that qualified laboratory staff have input into defining the specifications for reagents, consumables and equipment; and streamlining of importation and in-country distribution procedures to ensure sufficient shelf life of reagents and consumables, once they reach testing sites;
- careful monitoring of consumption rates, tracking of reagent-specific shelf lives and forecasting to avoid expirations or stock-outs;
- careful planning to ensure that sites have received training and that equipment has been installed ahead of shipment of reagents;
- ongoing monitoring of all procurement and supply chain steps, to ensure that delays are minimized and that sites receive correct reagents as per the planned schedule; and
- regular reassessment of purchasing and distribution strategies, to ensure that they are responsive to needs and the current situation.
Step 4.2 – Develop procedures to monitor reagent quality and shelf life
The shelf life of reagents and their required storage conditions must be considered when designing a procurement and distribution system. Laboratory managers should routinely monitor reagent quality and shelf life to ensure that high-quality test results are generated. Also, the laboratory must establish SOPs for handling the reagents and chemicals used, to ensure both quality and safety. The shelf life of NGS reagents is normally short; hence, robust planning is required to avoid kits expiring, with resulting high costs for testing.
New-lot testing, also known as lot-to-lot verification, should be performed on new batches of reagents or test kits. Such testing usually involves testing a sample of the new materials and comparing the results to an existing lot of materials with known performance. Preferably, new-lot testing of commercially available test kits is performed at the central (e.g. NTRL) or regional level, thereby ensuring that kits with test failures are not distributed. At the testing site, new-lot testing is needed for reagents prepared at that site; it may also be needed to monitor conditions during transport and storage of test kits within the country. For QC, WHO recommends using positive and negative controls when testing new batches of reagents.