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20 th International AIDS Conference | 24 July 2014 1 |1 | Protecting the quality of HIV testing in the new HIV testing environment 20 th International AIDS Conference 24 July 2014, Melbourne Anita Sands Prequalification Team – Diagnostics Department of Essential Medicines & Health Products 20 th International AIDS Conference 24 July 2014, Melbourne Anita Sands Prequalification Team – Diagnostics Department of Essential Medicines & Health Products
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20 th International AIDS Conference | 24 July 2014 2 |2 | Background Quality of all HIV testing is a priority –Incorrect HIV testing results will occur without a framework to guide quality of testing 3 C's to the 5 C's –Consent –Confidentiality –Counselling –Correct test results –Connection/linkage to prevention, care and treatment
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20 th International AIDS Conference | 24 July 2014 3 |3 | Where to deliver HIV testing Universal access to HTC Community based HTC Home-based Quality standards for all HTC settings Facility based HTC Outreach (key pop) Events Workplace Schools PITC Clinical settings PITC Clinical settings Other facilities e.g. stand-alone VCT
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20 th International AIDS Conference | 24 July 2014 4 |4 | Framework for quality of HIV testing Selection of testing strategy List of prequalified diagnostics National testing and QA policies Validation of testing algorithm(s) Procurement of diagnostics Post-market surveillance National regulatory framework for diagnostics Training Quality assurance Supported by Guided by
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20 th International AIDS Conference | 24 July 2014 5 |5 | WHO Prequalification of Diagnostics Pre-submission form Dossier review Site inspection Laboratory evaluation Dossier incomplete Prequalification decision Dossier complete Dossier screening Priority product Yes No
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20 th International AIDS Conference | 24 July 2014 6 |6 | Framework for quality of HIV testing Selection of testing strategy List of prequalified diagnostics National testing and QA policies Validation of testing algorithm(s) Procurement of diagnostics Post-market surveillance National regulatory framework for diagnostics Training Quality assurance Supported by Guided by
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20 th International AIDS Conference | 24 July 2014 7 |7 | Testing strategy for diagnosis: high prevalence >5% Result: A1- Report: HIV negative Result: A1- A2- Report: HIV negative Result: A1+ A2- Result: A1+ A2- A3+ Report: HIV inconclusive Result: A1+ A2- A3- Report: HIV negative Conduct A2 Result: A1+ A2+ Report: HIV positive Conduct A1 Result: A1+ Conduct A3 Result: A1+ A2- Repeat A1 and A2 Source: HIV Assays Report 17 http://apps.who.int/iris/bitstream/10665/93679/1/97 89241506472_eng.pdf
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20 th International AIDS Conference | 24 July 2014 8 |8 | Testing strategy for diagnosis: low prevalence <5% Result: A1- Report: HIV negative Result: A1+ A2 - Report: HIV negative Result: A1- A2 - Report: HIV negative Result: A1+ A2 + Result: A1+ Result: A1+ A2 - Repeat A1 and A2 Result: A1+ A2+ A3+ Report: HIV positive Result: A1+ A2+ A3- Report: HIV inconclusive Conduct A2 Conduct A3 Conduct A1 Source: HIV Assays Report 17 http://apps.who.int/iris/bitstream/10665/93679/1/97 89241506472_eng.pdf
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20 th International AIDS Conference | 24 July 2014 9 |9 | Framework for quality of HIV testing Selection of testing strategy List of prequalified diagnostics National testing and QA policies Validation of testing algorithm(s) Procurement of diagnostics Post-market surveillance National regulatory framework for diagnostics Training Quality assurance Supported by Guided by
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20 th International AIDS Conference | 24 July 2014 10 | Validation of testing algorithms How to chose the assays to be used as Assay 1, Assay 2, and Assay 3? Assay 1 = most sensitive –Assay 2 and Assay 3 = most specific –Poor choice of Assay 2 and 3 may lead to high rates of misclassification Defined national testing algorithms –With back-up options in case of stock-outs or product failures
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20 th International AIDS Conference | 24 July 2014 11 | (Un) clear test instructions Example of HIV diagnostic rapid test procedure: 1.Using one of the disposable pipettes supplied, fill with specimen. 2.Holding the pipette over the specimen well, add two drops of specimen (approx. 50μl). 3.Add 2 drops of buffer (approx. 60μl) to specimen well. 4.Allow 5 – 20 minutes from the time of buffer addition for the reaction to occur. For strongly positive results, the test line may become visible earlier. It is advisable to wait the full 20 minutes for negative results.
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20 th International AIDS Conference | 24 July 2014 12 | Critical parts of test procedure Volume of specimen –Too little = reduced sensitivity Volume of buffer –Too much = test may overflow –Too little = specimen will not flow through the device Reading time –Too soon = high background –Too late = reduced specificity
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20 th International AIDS Conference | 24 July 2014 13 | WHO post-market surveillance WHO is developing guidance for both reactive and proactive elements of post-market activities End-users, manufacturers, NRAs all have a role WHO prequalified product Reactive PMS Field Safety Notice Complaints Lot verification testing Proactive PMS Field Safety Corrective Action
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20 th International AIDS Conference | 24 July 2014 14 | Framework for quality of HIV testing Selection of testing strategy List of prequalified diagnostics National testing and QA policies Validation of testing algorithm(s) Procurement of diagnostics Post-market surveillance National regulatory framework for diagnostics Training Quality assurance Supported by Guided by
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20 th International AIDS Conference | 24 July 2014 15 | Quality assurance Using ISO 15189 as the standard and CLSI GP26- A4 as guidance External quality assessment (EQA) –Verifies the proficiency of the testing process Quality Control (QC) –Verifies the test is working correctly Process Control Quality Control & Specimen Management Purchasing & Inventory Assessment Occurrence Management Information Management Process Improvement Customer Service Facilities & Safety Organization Personnel Equipment Documents & Records
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20 th International AIDS Conference | 24 July 2014 16 | Assuring quality of community-based HTC Keep the service delivery model simple Community workers (operators) must be trained and proficient in specimen collection, test procedure, reading of results, and interpreting results Support from the laboratory is crucial Ensure linkage to treatment and care –For additional testing to confirm the diagnosis, and preferably at a site that performs treatment assessment i.e. CD4 count for ART initiation
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20 th International AIDS Conference | 24 July 2014 17 | Framework for quality of HIV testing Selection of testing strategy List of prequalified diagnostics National testing and QA policies Validation of testing algorithm(s) Procurement of diagnostics Post-market surveillance National regulatory framework for diagnostics Training Quality assurance Supported by Guided by
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20 th International AIDS Conference | 24 July 2014 18 | Training and proficiency Competency-based training Proof of proficiency with panel of HIV + and HIV - specimens –Proficiency for the entire testing algorithm, not just test procedure Simple SOPs –Easy to read job aids
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20 th International AIDS Conference | 24 July 2014 19 | WHO normative guidance WHO service delivery approaches to HTC: a strategic policy framework –http://apps.who.int/iris/bitstrea m/10665/75206/1/978924159 3877_eng.pdf WHO handbook for improving HIV testing and counselling services –http://www.who.int/hiv/pub/vct/ 9789241500463/en/index.html
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20 th International AIDS Conference | 24 July 2014 20 | WHO/CDC training package Training package –Participants manual –Trainers guides –Visual aids Requires local adaptation http://www.who.int/diagnostics_laboratory/documents/guidance/hivrttraining_overview/en/index.html Undergoing revision
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