Résumé
Variation in HIV-1 genomic RNA was studied in seroconversion samples from mother–child pairs from a Rwandan cohort. The mothers (n= 8) were heterosexually infected and their children (n= 6) were vertically infected by breast milk. Five of the children seroconverted within the same 3-month period as did their mothers. Highly homogeneous subtype A V3 and p17gagsequence populations were observed in three mother–child pairs, one of the two nontransmitting mothers, and one child (mean nucleotide distances 0 to 0.9%). Heterogeneous populations of subtype A V3 and p17gagsequences were found in one mother and a mother–child pair (1.4 to 2.8% for V3, 1.0 to 1.9% for p17). The second nontransmitting mother was infected with a heterogeneous AV1-V3/Cp17-p24recombinant virus population (3.8% for V3, 2.4% for p17). Finally, in one woman subtype C V3 sequences were observed, in addition to highly homogeneous subtype A V3 and p17gagsequence populations, also found in the child. Coexistence of subtype AV1-V3and CV1-V3envsequences in the mother was confirmed in a follow-up sample. Thegaggene of both the maternal and the child's virus population represented an A/C recombinant sequence (Ap17/Cp24). An infection with subtype CV1-V3/p17-p24was found upon testing of three additional participants of the mother–child cohort, indicating that subtype C is present in Rwanda. In conclusion, heterogeneity, coinfection, and intersubtype recombinants are not uncommon in primary HIV-1 infections in Rwanda.