Molecular evidence for transmission of viruses: hepatitis B and C viruses and human immunodeficiency virus

Securing molecular evidence for transmission of RNA viruses is critically d ependent on the time elapsed after infection. To establish HCV transmission by blood transfusions from specific donors, we deduced the sequence of ami no acids 329 to 410 of HCV in 30 transfusion recipients and 120 of their bl ood donors. Phylogenetic analyses of hypervariable region 1 (HVR1) and geno typing furnished proof of transmission. Linear regression analysis showed n o differences between HVR1 sequences from the recipient and the implicated donor up to 7.9 weeks post-transfusion, but donor and recipient sequences d iverged subsequently (r = 0.690). The choice of viral genomic region is als o important. We compared four genomic regions in HIV-1 encoding variable re gions V1, V2 and V3 in the env gene and p2 in the gag gene in documented ca ses of mother-to-infant HIV-1 transmission. The less variable regions of V3 and p2 provided positive evidence for virus transmission, in contrast to r esults obtained on highly variable regions V1 and V2 ( p < 0.05). Intrafami lial transmission of hepatitis B virus, a DNA virus, could be demonstrated on the molecular level by sequencing of a 100-nucleotide region of the vira l genomes from 96 Chinese children and their parents. In 28 of the 30 mothe rs and 6 of 8 fathers, sequences were identical to those of their offspring ( p < 0.00005). (C) 2001 Elsevier Science B.V. All rights reserved.