Table 1.

Frequency of amplification of HIV-1 pol from plasma or DBSs stored at −20°C for 6 months or at 4°C for 12 months

Specimen ID	Plasma VL (log10 copies/mL)	CD4 cells/mm3	Plasmaa	DBS (−20°C, 6 months, ViroSeq assay)b	DBS (4°C, 12 months, ViroSeq assay)	DBS (4°C, 12 months, in-house assay)
1	676 694	32	+	+	+	+
2	266 612	195	+	+	+	+
3	214 330	195	+	+	+	+
4	191 674	48	+	+	+	+
5	170 289	663	+	+	+	+
6	90 758	324	+	+	+	+
7	63 261	169	+	+	+	+
8	51 598	324	+	+	+	+
9	52 342	457	+	+	+	+
10	49 805	450	+	+	+	+
11	37 010	152	+	+	+	+
13	30 267	525	+	+	+	+
14	28 742	378	+	+	+	+
16	23 352	221	+	+	+	+
17	23 321	168	+	+	+	+
18	21 896	391	+	+	+	+
19	17 563	289	+	+	+	+
20	16 359	609	+	+	n.s	+
21	14 622	483	+	+	+	+
22	13 952	396	+	+	+	+
23	13 407	224	+	+	+	+
24	12 452	374	+	+	−	+
25	12 307	465	+	+	+	+
26	12 264	1320	+	+	+	+
27	11 999	81	+	+	−	+
28	11 663	336	+	+	n.s	+
29	10 998	442	+	+	n.s.	−
30	9955	342	+	+	−	+
31	8316	288	+	+	−	+
32	4717		+	+	−	+
33	4349	990	+	+	−	+
34	4213	1080	+	+	−	+
36	3880	434	+	+	n.s.	+
37	3455	468	+	+	−	+
38	2240	154	+	+	+	+
39	1929	416	+	+	−	+
42	1254	858	+	+	−	n.s.
44	1045	360	+	+	−	+
45	929	63	+	+	n.s.	+
46	518	240	+	+	−	+

n.s., HIV-1 RT and protease were amplified but failed to generate full-length sequences.

^aPlasma genotypes were generated using the Viroseq assay except for 1, 3, 18, 32, 33, 39 and 42 (TrueGene assay).

^bAmplification from these DBSs stored at −20°C has been reported elsewhere.⁶