2014/LSIF/PD/025 Malaysia s Approach to Testing Strategies

Transcription

1 2014/LSIF/PD/025 Malaysia s Approach to Testing Strategies Submitted by: Malaysia Policy Dialogue and Workshop on Attaining a Safe and Sustainable Blood Supply Chain Manila, Philippines 30 September 1 October 2014

2 APEC POLICY DIALOGUE AND WORKSHOP ON ATTAINING A SAFE AND SUSTAINABLE BLOOD SUPPLY CHAIN Asian Institute of Management Conference Center Manila, Philippines 30 September 1 October 2014 Malaysia s approach to testing strategies Dr Yasmin Ayob

3 Content Background Malaysia approach System, policy and programme Ensuring Effectiveness standardisation, guidelines, monitoring National screening strategy The role of the reference laboratory Blood Screening Algorithm & Blood Release Conclusion

4 Background Population 30 million Annual Blood Collection approximately 750,000 units Mainly whole blood collection with some apheresis 450 ml per unit Prevalence of HBV is high in general population Prevalence of HBV in donor population per 1000 donation (HIV= 0.2; HCV = 0.8) HBV vaccination programme for neonates started in 1980s

5 Malaysia approach Establishment of systems to ensure that all donated blood is screened for transfusion-transmissible infections National policy on blood screening defines national requirements for the screening of all donations for transfusion-transmissible infections. National programme for blood screening which sets out the strategy for screening, with algorithms and defines actual tests to be used in each screening facility

6 National Policy National policy on blood screening, incorporated into the national blood policy, All donations should be screened for evidence of infection prior to the release of blood and blood components for clinical or manufacturing use. Screening of all blood donations is mandatory for HIV Hepatitis B Hepatitis C Syphilis (Treponema pallidum)

7 TTI Screening : Ensuring Effectiveness Blood screening is consolidated in strategically located facilities at 17 regional levels to achieve uniformity of standards, increased safety and economies of scale Criteria for setting up Transfusion Microbiology Lab There is a national system for the evaluation, selection and validation of all assays used for blood screening. National procurement policy and supply system to ensure the quality of test kits, and continuity reagents and other consumables Quality systems is in place for all elements of the blood screening programme, including standards, training, documentation and assessment (audit & NEQAP)

8 Distribution of Blood Screening Centres in Malaysia Reference Laboratory

9 National screening strategy provides an overall decision-making process on how tests are to be used and interpreted defines the outcomes of screening with regard to whether a blood unit will be released or discarded. defines in general terms how screening is to be performed and provide specific guidelines Transfusion Practice Guidelines for Clinical & Laboratory Personnel 4 th Edition)

10 National screening strategy Marker(s) to be screened for each infection HIV Ab/Ag, HCV Ab/Ag, HBsAg, Syphilis Ab, Assay(s) to be used for each marker EIA in 16 centres & Chemiluminescence in the reference lab Nucleic Acid Amplification Testing (NAT) Interpretation of the results of screening tests, including: o The definition of initially reactive and non-reactive blood donations o the decision points for the release of non-reactive units

11 National screening strategy Initially reactive tests must be repeated ; Initially reactive donations are discarded even if nonreactive on repeat testing Procedures for the quarantine and release or discard of blood and blood components Confirmatory testing are performed to distinguish between true reactivity and non-specific reactivity for donor management Subsequent actions Donors whose blood tests are repeat reactive, but are not confirmed positive: i.e. donors are notified and counselled concerning possible non-specific or biologically false reactive results. All confirmed positive donors are counselled & referred to Infectious Disease clinics

12 National screening strategy Standardised Screening Algorithm sequence of steps in the blood screening process to be followed in each of the screening centres to determine the suitability of each unit of donated blood and its components for clinical or manufacturing use. It specifies the actual tests to be used and, based on each test result, directs the user to the next step. Donor look-back and recipient follow-up Safe disposal of reactive and positive units.

13 The role of the reference laboratory TTI Reference lab in NBC KL Evaluation and selection of assay systems and equipment Confirmatory testing on screened reactive donations for blood donor management HCV & HIV (HBV done at the screening centre) Organization of external quality assessment schemes. Carries out surveillance for other markers in the donor population Provide training

14 Blood Screening Algorithm & Blood Release Production Unit (PU) TTI screening Laboratory Quarantine all blood bags Test Pilot Tubes Retrieve all blood bags that correspond with initial reactive pilot tubes Release Initial Result to PU Send initial reactive blood bags to screening lab for sample verification testing Repeat screening of samples from blood bag & corresponding pilot tubes of all initial reactive samples

15 Blood Screening Algorithm & Blood Release Production & Fractionation Unit TTI screening Laboratory Test sample from blood bags & pilot tubes Result is repeatedly reactive Discrepant results Remove all RR bags + components, label as Biohazard; send all to screening lab for confirmation/disposal Receipt of official result Final labels on all negatives- SCREENED ; Release to inventory Release of official result to PU Quarantine blood collected from the same site on the sane date, Carry out investigation

16 Investigation of discrepant results Recheck sample ID of implicated pilot tube & blood bag Check blood group of implicated samples Rerun screening tests on blood bags of the same blood group from implicated batch Release final results obtained from blood bag samples Recall all donors with same blood group if problem is not resolved

17 Nucleic Acid Testing Pilot study done 2005 NAT only positive = 1 in 1,800 Estimated cost of preventing 1 transmission was RM56,250 (16,000 USD) Implemented in 2007 Current NAT only positive = 1in 6,000

18 NBC KL s ID-NAT Test Algorithm Ultrio Initial reactive Ultrio repeat 1 Ultrio repeat 2 Ultrio repeat 3 When Ultrio is reactive Perform triplicate Ultrio on Pilot Tube and dhxv tests on plasma bag Confirm by follow up and alternate NAT Perform anti-hbc, and anti-hbs titer to discriminate between WP and OBI Abd Hamid ISBT Congress KL 2013

19 NBC KL s ID-NAT Screening Algorithm in SeroNEGATIVE Donations ID-NAT IR seronegative Confirmation testing on plasma bag sample 3x Ultrio and 3x dhxv assays Alternate NAT 3x Ultrio on 1 tube NRR RR Potential NAT yield Additional HBV serologic markers (anti-hbc, anti-hbs, Anti-HBe, HBeAg) False Positive Discard all blood product; no recall; eligible for future donation Recall for confirmation of seroconversion or OBI Abd Hamid ISBT Congress KL 2013

20 Conclusions Transfusion is an irreversible event which carries potential benefits as well as risks to the already critical patients. TTI is still a major risk even with testing Establishment of systems is important to ensure that all donated blood is screened for transfusion-transmissible infections - core component of every national blood programme. Policy, algorithm, process & procedure has an impact in reducing TTI A strict vigilance on TTI monitoring system, surveillance, - decision making, interventions National screening algorithms and guidelines help to ensure consistency in screening tests and decisions regarding the release of screened blood and blood components, the discard of unsuitable units and the management of blood donors with confirmed positive screening results.

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