Distribution of study participants (total and maternal nevirapine-stratified groups) according to cohorts previously described and maternal viral load (VL) and CD4 counts.

-: Not applicable (EU infants) and not determined (INF infants). *: Described in Kuhn et al. (2007). a:10 IPs (43%) + 13 IUs (56%) = 23 (known mode of transmission); 19 = unknown mode of transmission. b:16 IPs (69.6%) + 7 IUs (30.4%) = 23 (known mode of transmission); 1 = unknown mode of transmission. c:10 IPs (45.5%) + 12 IUs (54.6%) = 22 (known infection route); 19 = unknown infection route. d:16 IPs (69.6%) + 7 IUs (30.4%) = 23 (known infection route); 1 = unknown infection route.