IPFA/PEI, Italy
NAT Screening of Blood Donations in NBC, TRCS 2000-2001 Clinical evaluation using COBAS AmpliiScreen HIV & HCV assays, (MP24) window period rate - 1 : 108,768 for HIV-1 and HCV 2002 Routine service for HIV/HCV (on request) 2006 100% of blood donations screened by Procleix HIV-1/HCV (IDT) June 2006: moved to Ultrio HIV-1/ HCV/ HBV (MP16) 2007 One year evaluation of NAT screening for HIV-1/HBV/HCV by Procleix Ultrio/Tigris system (IDT) vs cobas s 201/MPX v1 system (MP6) 2008-2013 cobas s 201 system and MPX v1 (MP6) 2014 Change to MPX v2 (MP6)
TTIs Screening Algorithm at TRC All blood donations initially tested by Abbott Architect i6000 for: - HBsAg, Anti-HCV, HIV Ab/Ag Combo & Syphilis Confirmatory test - HBsAg reactive Abbott HBsAg Neutralization test Only serology negative (HBsAg, Anti-HCV, HIV Ab/Ag ) samples tested by NAT - Samples tested in pools of 6 with Roche cobas MPX test v1 and MPX v2 on cobas s 201 platform
Prevalence of Serological and NAT Markers in Thai Blood Donations tested at NBC and RBCs in 2013 Test No. tested Syphilis HBsAg Anti-HCV HIV Ag/Ab Serology 1,813,821 3,811 (0.32%) 14,225 (1.2%) 4,100 (0.35%) 1,383 (0.12%) Test No. tested NAT yield HBV HCV HIV NAT 1,404,634 1 : 2800 486 7 16
NAT Tests: cobas MPX v1 and MPX v2 Donations tested in pools of 6 Donations in reactive pools tested individually to identify reactive donation MPX v1 Multiplex test for simultaneous detection of HBV DNA, HCV RNA, HIV-1 RNA and HIV-2 RNA Reactive donations tested with COBAS TaqMan (CAP/CTM)/ COBAS AmpliScreen tests for HBV, HCV and HIV-1 to identify viral target in reactive donation (VTR) MPX v2 Multiplex test for simultaneous detection of HBV DNA, HCV RNA, HIV-1 RNA and HIV-2 RNA and identification of HBV, HCV and HIV (viral target resolution testing not required)
Donor primary tubes (serology negative) Pool of 6 Flow Chart of NAT Testing of Blood Donations with the cobas TaqScreen MPX v1 NAT for HIV/HCV/HBV Initial reactive pool Test 6 samples from reactive pool using samples from primary tubes or archive plate Pool nonreactive Release all 6 donations All 6 samples non- reactive Reactive samples Repeat from plasma bags (duplicate) Non reactive One or both replicates reactive Viral Target Resolution *** with sample from bag HIV Reactive unit Discard blood unit Follow-up donor - full HBV serology profile and NAT Nonreactive unit Non- reactive unit Send to Siriraj Hospital for comfirmation (high speed centrifugation + COBAS AmpliScreen Test) Reactive unit Discard blood unit Follow up donor - full HBV serology profile and NAT HCV HBV
Serology and NAT Screening, MPX v1(2013) Parameters Results Serology No. of donations screened 640,137 No. of sero-positive donations 4,606 (0.72%) NAT screen No. of donations screened 595,059 No. of pools screened 99,180 No. of initially reactive pools 437 (0.44%) No. of pools that resolved to 1 or more reactive donations (repeat reactive) 248 (0.25%) No. of false reactive pools 189 (0.19%)
NAT-only Yield, MPX v1(2013) Parameters Results No. of reactive donations on pool resolution (RR) 248 No. of RR/ not confirmed (samples from plasma bags) donations 55 (22.2%)** No. of RR/ confirmed (samples from plasma bags) donations 193 (77.8%) No. of RR/confirmed, VTR-negative donations 35 (18.1%)** No. of RR/confirmed, VTR-positive donations 158 (81.9%) (5 HIV,2 HCV, 151 HBV) No. of RR/confirmed, HBV VTR-positive donors followed 41 out of 151 (27.2%)** ** Follow up donor full HBV serology profile & NAT
MPX v1: Follow-up Data from RR/Not Confirmed Donors 31 of 55 (56%) RR/ not confirmed donors were followed (follow-up samples from 1-13 months after index donation) All donors were negative for HBsAg and anti-hbc IgM ALT ranged from 7-44 IU/L, 5/30 (17%) >35 IU/L, 1 donor ALT = 226 IU/L Serology + NAT markers No. of donors HBV status All negative 1 False reactive Anti-HBc 2 Occult Anti-HBs 3 Occult Anti-HBc +anti-hbs 12 Occult Anti-HBc +anti-hbs + anti-hbe 8 Occult Anti-HBc + NAT 1 Occult Anti-HBs + NAT 1 Occult Anti-HBc +anti-hbs + NAT 1 Occult Anti-HBc +anti-hbs + anti-hbe + NAT 2 Occult
MPX v1: Follow-up Data from RR/Confirmed/VTR Negative Donors 21 of 35 (60%) RR/Confirmed/VTR Negative donors were followed (samples from 1-19 months after index donation) T ranged from 10-34 IU/L, 1 donor ALT = 43 IU/L ALT ranged from 10-34 IU/L (1 donor ALT = 43 IU/L, 1 donor = 61 IU/L ) Serology + NAT markers No. of donors HBV status NAT 1* Acute WP infection HBsAg + NAT 1* Acute WP infection Anti-HBc +anti-hbs 8 Occult Anti-HBc +anti-hbs + anti-hbe 4 Occult Anti-HBc + NAT 2 Occult Anti-HBc +anti-hbs +NAT 3 Occult Anti-HBc +anti-hbs + anti-hbe + NAT 2 Occult * 1 month follow-up sample
MPX v1: Follow-up Data from HBV Reactive Donors 41 of 151 HBV-reactive donors (27.2%) were followed NAT + full HBV serology profile were done on follow-up samples 12 breakthrough infections 2 unclassified 3 acute infections 24 occult HBV infections
MPX v1: HBV NAT and Serology Profile of Donor Follow-up Samples - Breakthrough HBV Infection? Donor no. Followup (months) ALT HBsAg Anti-HBs (miu/ml) Anti- HBc IgM Anti-HBc IgG Anti-HBe 8932 8 11 0.15 >1000 + + + - NAT (Ct) 0796 8 88 0.24 >1000 + + + 41.9 3855 2 16 0.21 >1000 + + + - 2694 4 19 0.13 >1000 + + + - 0486 3 20 0.16 >1000 + + + - 0483 4 13 0.19 >1000 + + + - 2977 4 12 0.21 >1000 + + + - 5063 4 64 0.18 852.4 + + + 42.3 0171 4 23 0.16 525.8 + + + - 0163 3 79 0.21 353.10 + + + 34.3 5028 3 29 0.17 189.0 + + - - 9111 3 49 0.14 55.65 + + + -
MPX v1: HBV NAT and Serology Profile of Donor Followup Samples - Unclassified? Donor no. Followup (months) ALT HBsAg Anti-HBs (miu/ml) Anti-HBc IgM Anti-HBc IgG Anti-HBe 6757 4 8 0.18 - + + + - NAT (Ct) 1655 2 23 0.18 - + + + 39.4
MPX v1: HBV NAT and Serology Profile of Donor Followup Samples - Acute HBV Infection? Donor no. Followup (months) ALT HBsAg Anti-HBs (miu/ml) Anti-HBc IgM Anti-HBc IgG Anti-HBe NAT (Ct) 2235 1 15 95.14 - - - - 24.0 1723 1 15 1834.98 - - - - 16.0 9207 6 6 98.08 - - + + 36.4
HBV NAT and Serology Profile of Donor Follow-up: Occult HBV Infection? Possible occult HBV infection: 24donors Follow-up sample from 1-13 months after index donation A ALT ranged from 8-72 IU/L, 6/25 (24%) >35 IU/L from 8-72 IU/L, 6/25 (24%) >35 Serology + NAT markers No. of donors HBV status Anti-HBc + anti-hbs 8 Occult Anti-HBc + anti-hbe 1 Occult Anti-HBc + anti-hbs + anti-hbe 5 Occult Anti-HBc + anti-hbs + NAT 2 Occult Anti-HBc + anti-hbe + NAT 5 Occult Anti-HBc +anti-hbs + anti-hbe + NAT 3 Occult
Donor primary tubes (serology negative) Pool of 6 Flow Chart of NAT Testing of Blood Donations with the cobas TaqScreen MPX v2 NAT for HIV/HCV/HBV Initial Reactive pool Test 6 samples from reactive pool using samples from archive plate Pool nonreactive Release all 6 donations All 6 samples non- reactive Reactive samples HIV/HBV/HCV Repeat from plasma bags (duplicate) Non reactive One or both replicate reactive Discard blood unit NAT on 5 replicates Follow-up donor by NAT NAT testing 5-10 replicates Discard blood unit Follow up donor - full HBV serology profile and NAT
MPX v2: NAT-only Yield Parameters Results No. of donations screened 189,087 No. of pools screened 31,517 No. of initially reactive pools 135 (0.42%) No. of pools that resolved to one or more reactive donations 48 (0.15%) No. of false reactive pools 87(0.28%) No. of RR/ confirmed (samples from plasma bags) donations 44 (91.7%) 2 HIV, 42 HBV No. of RR/ not confirmed (samples from plasma bags) donations 4 (8.3%)* *Since MPX v2 was a new test, all RR/not confirmed samples were retested (5-10 replicates)
MPX v2: HBV NAT and Serology Profile of 4 Repeat Reactive/Not Confirmed Donors Donor no. Replicate testing No. reactive/no. tested Sex Age Anti-HBs (>10 IU/L positive) Anti-HBc IgM Anti-HBc Anti-HBe ALT 0609 0/5 M 26 + (26.29) - + + 23 1227 2/10 M 59 - (5/16) - + - 11 1767 1/10 F 30 - (<2.0) - - - 9 9604 1/10 F 51 + (75.46) - + - 12
Conclusions Both MPXv1 & MPXv2 gave the same percentage of initially reactive pools (0.44% - 0.42%). MPX v1: Almost all follow up donors of RR/not confirmed and RR/ confirmed/vtr negative donations were occult HBV, although 2 of the later group were acute infections. Majority of confirmed HBV reactive donors also had occult HBV. Occult MPX v2: Majority of RR/not confirmed HBV donations had occult HBV with very low viral load. Study shows that majority of HBV infections in Thai blood donors tested by NAT had occult HBV. Some of them can be extremely difficult to detect. Testing of NAT RR sample with multiple replicate as well as full HBV serology profile are important to confirm HBV low viral load.
Question
Prevalence of serological markers(%) in blood donations tested at NBC and RBCs in 2013 1.60% 1.40% 1.20% 1.00% 0.80% 0.60% 0.40% 0.20% 0.00% Syphilis HBsAg Anti-HCV HIV Ag/Ab NBC 0.12% 0.34% 0.15% 0.01% Central R(RBC2,3,4) 0.36% 0.98% 0.14% 0.11% Northeast R(RBC 5,6,7) 0.35% 1.35% 0.59% 0.14% North R (RBC 8,9,10) 0.31% 1.51% 0.35% 0.10% South R (RBC 11,12, Phuket) 0.29% 0.78% 0.21% 0.13%
NAT yield rate tested at NBC & RBC in 2013 NAT center No. of samples tested Number of reactive samples (NAT yield) HIV HCV HBV No plasma sample to be confirmed/vtr NBC, TRCS 636,330 (NAT Yield) 5 (1:127,000) 2 (1:318,000) 163 (1:3,900) 0 Central & East R (RBC 2,3,4) 252,077 (NAT Yield) 4 (1:63,000) 3 (1:84,000) 90 (1:2,800) 47 Northeast R (RBC 5,6,7) 192,706 (NAT Yield) 3 (1:64,000) 1 (1: 192,000) 82 (1:2,400) 97 North R (RBC 8,9,10) 190,484 (NAT Yield) 2 (1:95,000) 1 (1:190,000) 113 (1:1,700) 51 South R (RBC11,12, Phuket) 133,037 (NAT Yield) 2 (1: 67,000) 0 38 (1: 3,500) 17 Overall NAT Yield 1,404,634 16 (1:88,000) 7 (1: 200,000) 486 (1: 2,900) 212