Sheila F O'Brien1, Qi-Long Yi2, Wenli Fan3, Vito Scalia3, Mindy Goldman4, Margaret A Fearon5. 1. Canadian Blood Services, Canada; Dept. of Epidemiology & Community Medicine, University of Ottawa, Canada. Electronic address: sheila.obrien@blood.ca. 2. Canadian Blood Services, Canada; Dept. of Epidemiology & Community Medicine, University of Ottawa, Canada. 3. Canadian Blood Services, Canada. 4. Canadian Blood Services, Canada; Dept. of Pathology & Laboratory Medicine, University of Ottawa, Canada. 5. Canadian Blood Services, Canada; Dept. of Medical Microbiology, University of Toronto, Canada.
Abstract
BACKGROUND: Residual risk is estimated as the product of the incidence and the infectious window period, the time during which a blood donation could be infectious but the assay may not detect it. In 2011 nucleic acid multiplex testing (MPX) was implemented in 6 unit minipools (previously 24 unit minipools). MPX also included hepatitis B (HBV) NAT for the first time (complementing HBsAg screening) in addition to HIV-1 and hepatitis C (HCV) as before. We aimed to estimate window period risk-day equivalents for MPX, and the residual risk of viral infections in blood donations updated to reflect current incidence and testing. METHODS: Transmissible disease conversions of repeat donations to Canadian Blood Services within the three-year period 2012-2014 divided by person-years estimated incidence for HIV, HCV and HBV (adjusted for transient viremia). Window period risk-day equivalents for MPX were estimated using a published method. Residual risk was the product of incidence and window period risk-day equivalents. 95% confidence intervals were estimated using Monte Carlo simulation of the window period risk-day equivalents and the incidence density 95% confidence intervals. RESULTS: The incidence rate per 100,000 person years for HIV was 0.28, HCV 1.0 and HBV 0.26. The residual risk of HIV was 1 per 21.4 million donations, HCV 1 per 12.6 million donations and HBV 1 per 7.5 million donations. CONCLUSION: The residual risk of infection is very low, similar to 2006-2009. The safety benefit of further shortening of the infectious window period is below the threshold to quantify.
BACKGROUND: Residual risk is estimated as the product of the incidence and the infectious window period, the time during which a blood donation could be infectious but the assay may not detect it. In 2011 nucleic acid multiplex testing (MPX) was implemented in 6 unit minipools (previously 24 unit minipools). MPX also included hepatitis B (HBV) NAT for the first time (complementing HBsAg screening) in addition to HIV-1 and hepatitis C (HCV) as before. We aimed to estimate window period risk-day equivalents for MPX, and the residual risk of viral infections in blood donations updated to reflect current incidence and testing. METHODS: Transmissible disease conversions of repeat donations to Canadian Blood Services within the three-year period 2012-2014 divided by person-years estimated incidence for HIV, HCV and HBV (adjusted for transient viremia). Window period risk-day equivalents for MPX were estimated using a published method. Residual risk was the product of incidence and window period risk-day equivalents. 95% confidence intervals were estimated using Monte Carlo simulation of the window period risk-day equivalents and the incidence density 95% confidence intervals. RESULTS: The incidence rate per 100,000 person years for HIV was 0.28, HCV 1.0 and HBV 0.26. The residual risk of HIV was 1 per 21.4 million donations, HCV 1 per 12.6 million donations and HBV 1 per 7.5 million donations. CONCLUSION: The residual risk of infection is very low, similar to 2006-2009. The safety benefit of further shortening of the infectious window period is below the threshold to quantify.
Authors: Sheila de Oliveira Garcia Mateos; Liliana Preiss; Thelma T Gonçalez; Claudia Di Lorenzo Oliveira; Eduard Grebe; Clara Di Germanio; Mars Stone; Luiz Amorim Filho; Anna Bárbara Carneiro Proietti; Andre Rolim Belisario; Cesar de Almeida-Neto; Alfredo Mendrone-Junior; Paula Loureiro; Michael P Busch; Brian Custer; Ester Cerdeira Sabino Journal: Vox Sang Date: 2020-09-30 Impact factor: 2.144
Authors: Ruchika Goel; Molly R Petersen; Eshan U Patel; Zoe Packman; Evan M Bloch; Eric A Gehrie; Parvez M Lokhandwala; Paul M Ness; Beth Shaz; Louis M Katz; Steven M Frank; Aaron A R Tobian Journal: Transfusion Date: 2020-08-31 Impact factor: 3.157