SoGAT XVII, Paris, Paris 2004

1. SoGAT XVII, Paris, Paris 2004 B19 Overview of Testing for Blood Banks W. Kurt Roth Red Cross Blood Transfusion Service Baden-Württemberg – Hessen, Institute Frankfurt am Main

2. Parvovirus B19-PCR: Testing Strategy • Quantitative real-time TaqMan PCR • Internal control sequence • 3 external quantitative standards: 106, 105, 104 IU/ml on each plate • External standards are spiked in negative plasma • Routine donor screening on pools of 96 • Testing in parallel with HCV, HIV, HBV, HAV • Testing for all blood components incl. red cells and platelets • No exclusive and no delayed testing for source plasma • 95% detection limit: 103 IU / ml • Decision level  105 IU / ml

6. Parvo B19 Positives per Month Positives 105 (n)

7. B19 positives in March - April 2004 March April * Indicates at least 1 donation/pool

8. Parvovirus B19-PCR: Decision Making • B19 positive Pools  105 IU / ml: • Positive donation identified • Positive donation destroyed • No donor deferral • No donor information or counseling • Reentry after donor tests PCR-negative (detection limit < 100 IU/ml) • B19 „weak“ positive Pools < 105IU / ml: • Positive donation not identified • All donations released (weak positive for blood bank software) • No labelling of product as B19 weak positive • Parvo B19-negative and weak positive (> 103 ; < 105 IU / ml) components for all patients at no specific risk • standard quality

9. Indications for B19-negative components • Parvo B19-negative (< 103 IU / ml) components upon specific written request; individual label: „Parvovirus B19 not detectable“ • Patients with BMT, SCT • B19 antibody-negative pregant women in the 1.and 2. trimenon • HIV patients • Additional risk groups e.g. • transient aplastic crisis • pure red cell aplasia

10. The Netherlands approach: Cellular components • B19 virus safe cellular products to risk groups only: • Pregnant women • Patients with congenital or acquired haemolytic anemia who have no antibodies • Patients with cellular immunodeficiency who have no antibodies • Safe products are: • IgG antibodies against B19 in two separate blood samples, one taken at least six months after the other. • To be introduced in 1st of July 2004 • To be introduced for quarantine plasma in April 2005

11. The Netherlands Approach: Plasma Products • All products derived from pooled plasma: • Highly infectd donations should be identified and removed before the individual sampkles are pooled. • For final pools the maximum permissible limit is 104 genome copies of B19 per millilitre. • NAT for pools of 480 (10 x 48) • one central facility ín Amsterdam. • minipool NAT for HCV and HIV: pools of 48 at 4 test centers.

12. The future approach? • B19 PCR and Ab testing on all donations • Release PCR-only negatives and PCR negatives/Ab positives • PCR negative/Ab positive products for patients at risk and source plasma • Discontinue PCR and Ab testing for repeat PCR-negatives/Ab positives • Continue PCR and Ab testing for first-time donors, antibody negative and PCR positive donors.

13. Parvo-B19 Seroconversion Medac IgM and IgG ELISA; Mikrogen IgG/IgM recomBlot