First transmission of human immunodeficiency virus Type 1 by a cellular blood product after mandatory nucleic acid screening in Germany

BACKGROUND: In February 2007, a 63‐year‐old man underwent surgery. Retrospective testing with nucleic acid testing (NAT) showed that the patient was human immunodeficiency virus Type 1 (HIV‐1) positive 10 days after transfusion. The transfusion‐transmitted infection had been identified by a donor‐related lookback started in April 2007 after anti‐HIV seroconversion. METHODS: Sequence analysis was performed in the gag‐pol region as well as in the V3 loop env region. Archived plasma from the transmitting donation was investigated for the individual‐donation NAT with the Roche COBAS AmpliPrep/COBAS TaqMan HIV‐1 test (Roche CAP/CTM HIV‐1 test) and for HIV antigen/antibody combination testing (Abbott Architect). Additional testing was done on the donor's follow‐up sample and on the recipient's sample. RESULTS: The Roche CAP/CTM HIV‐1 test failed to detect viral RNA by minipool NAT in the index donation (April 2007) as well as in the donation that caused the infection (January 2007). Phylogenetic analysis showed a very high genetic similarity among viral sequences from both donor and recipient, proving the HIV‐1 transmission by sequence data. CONCLUSION: This case represents the first documented HIV‐1 transmission by transfusion of red blood cells after mandatory introduction of HIV‐1 NAT for blood screening in Germany. Low viral load and mismatches in the primer/probe region might explain the detection failure of the NAT screening assay. A certain risk remains that new virus variants contain mutations at positions critical for amplification or detection of viral genomes. An option to reduce the risk of a detection failure by NAT is the simultaneous use of several conserved regions as amplification targets.