Table 3.

Mean pairwise genetic distances of Trinidad HIV-1 “signature” C2-V5 sequences by year

Year	Prevalent or incident	N	Pairwise distance	% Change
1990	P	4	7.17
1991	P	3	8.14	0.97
1993	I	5	8.11	−0.03
1994	I	6	9.6	1.49
1995	I	7	9.7	0.1
Totals		25	9.12	2.53 in 5 years (0.5% per year)

Samples containing the threonine deletion (N = 25) were used for this analysis, which calculates a summary measure per annum of inter-case sequence variability.