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Updated: Mar 30, 2026

Sequencing of Bacterial Microflora in Peripheral Blood: our Experience with HIV-infected Patients
Published on: June 11, 2011
Transmission of human immunodeficiency virus Type-1 by fresh-frozen plasma treated with methylene blue and light
Manuel Álvarez1, Mar Luis-Hidalgo1, María Alma Bracho2
1Valencian Regional Blood Transfusion Center, Valencia, Spain.
Background:
The risk of transfusion-transmitted infection (TTI) has been minimized by introduction of nucleic acid testing (NAT) and pathogen inactivation (PI). This case report describes transmission of human immunodeficiency virus Type 1 (HIV-1) to two recipients despite these measures.
Study Design And Methods:
In March 2009 a possible TTI of HIV-1 was identified in a patient that had received pooled buffy coat platelet concentrate (BC-PLT) in November 2005. The subsequent lookback study found two more patients who had received methylene blue (MB)-treated fresh-frozen plasma (FFP) and red blood cells (RBCs) from the same donation. In November 2005 the donor had tested negative for both HIV antibodies and HIV-1 RNA by 44 minipool (44 MP) NAT. Repository samples of this donation and samples from the recipients were used for viral load (VL) and sequence analysis.
Results:
HIV-1 RNA was detectable by individual donation (ID)-NAT in the repository sample from the 2005 window period donation and a VL of 135 copies/mL was measured. HIV-1 infection was confirmed in both recipients of both BC-PLT (65 mL of plasma) and MB-FFP (261 mL of plasma), but not in the patient that had received 4-week-old RBCs (20 mL of plasma). The sequence analysis revealed a close phylogenetic relationship between the virus strains isolated from the donor and recipients, compatible with TTI.
Conclusions:
Approximately 17,600 and 4400 virions in the MB-FFP and BC-PLT were infectious, but 1350 virions in the RBCs were not. ID-NAT would have prevented this transmission, but the combination of MP-NAT and MB-PI did not.

