Table 1. Summary of patient characteristics.

Patient code	CD4 cell count (cells/μl)*	Plasma HIV-1 RNA level (copies/ml)*	Documented PHI	Fiebig stage*	BED ODn*	Days last neg.-first pos.**	Estimated “true” time of infection (TI)	TI method	No. of samples	Days between TI and first sequence	Years between TI and last sequence
p1	537	<500	No	VI	0.419	310	7/9/1996	BED + Fiebig VI	12	122	8.2
p2	1185	31100	No	V	0.171	397	7/28/2002	Fiebig V	6	74	5.5
p3	694	17300	No	VI	0.898	575	9/3/1999	BED	10	146	8.4
p4	1064	6780	No	V	0.170	620	10/2/2000	Fiebig V	8	93	8.4
p5	521	<50	No	VI	0.153	196	12/10/2002	BED + Fiebig VI	7	134	5.9
p6	480	6800	Yes	IV	0.290	45	9/25/2002	PHI	7	62	7.0
p7	496	497	No	VI	nd	190	6/18/1990	Midpoint	10***	2248	15.9
p8	460	2900	No	V	0.158	299	4/19/1998	Fiebig V	7	87	6.0
p9	720	2300	No	VI	0.277	614	11/24/1996	BED + Fiebig VI	8	106	8.1
p10	420	594000	Yes	II	0.101	16	5/19/1990	PHI	9	33	6.2
p11	850	12700	No	VI	1.222	642	9/22/2000	BED	7	208	5.6

Table notes: PHI, primary HIV-1 infection; BED ODn, normalized optical density level in the BED serological assay; TI, estimated “true” date of infection;

*Results at baseline;

**Days between last negative and first positive HIV-1 test;

*** Sequencing of earlier time points failed due to low virus levels.