Table I.

Summary of the HIV serology and NAT results for the index donation and four subsequent follow-up samples from the case study donor. Results are included for testing at both the Australian Red Cross Blood Service (Blood Service) and the Victorian Infectious Diseases Reference Laboratory (VIDRL).

Date	Blood Service results				Victorian Infectious Diseases Reference Laboratory (VIDRL) results
	Serology		NAT		Murex 1.2 O HIV EIA	Western blot5	Abbott Real Time	Roche6
	Prism HIV O Plus s/co ratios1	Genscreen HIV Ultra s/co ratios2	Ultrio3	dHIV4
17/03/12 (index donation)	60.9 69.0, 67.2	7.5, 7.5	NR	NT	REA	p24++, gp160++	ND	NT
12/04/12	77.5 65.8, 65.5	11.7, 11.7	NR	NR	REA	p24++, gp 120+, gp160++	NT	ND
10/05/12	65.5 66.4, 66.7	13.0, 13.1	NT	REA	REA	p24++, gp 120+, gp160++	ND	NT
12/06/12	61.1 70.3, 65.3	13.2, 13.2	NR	NR	REA	p24++, gp 120+, gp160++	NT	ND7
21/06/12	70.3 83.3, 71.1	13.1, 12.2	NR	REA8	NT	NT	NT	ND9

¹s/co ratio: sample to cutoff ratio; s/co ratio ≥1.0 = REA; s/co ratios for initial test and duplicate repeat tests;

²s/co ratio: sample to cutoff ratio; s/co ratio ≥1.0 = REA; samples tested in duplicate;

³Ultrio: Procleix Ultrio multiplex assay;

⁴dHIV: Procleix HIV-1 discriminatory assay;

⁵MP Diagnostics HIV Blot 2.2;

⁶Roche Ampliprep/Taqman HIV-1 Test version 2.0;

⁷six of six replicates were non-reactive;

⁸two of 20 replicates were reactive;

⁹nine of nine replicates were non-reactive.

NAT: nucleic acid testing; HIV: human immunodeficiency virus; NR: non-reactive; NT: not tested; REA: reactive; ND: not detected.