Presence of multiple HIV subtypes and a high frequency of subtype chimericviruses in heterosexually infected women

The HIV-1 subtype distribution was determined in 41 HIV-positive women (sim ilar to 8% of all HIV-infected women in Denmark) belonging to different ris k groups. HIV p17 gag and env gene subtypes were determined by DNA sequence analysis. Five different HIV subtypes were detected across all patients. M ost HIV-1-positive women of Danish origin carried subtype B viruses, and a minority had virus belonging to subtypes A or C. All injecting drug users ( IDUs) were infected with HIV subtype B viruses, whereas all non-B subtypes were present in cases linked to heterosexual transmission. In contrast, all women of African origin carried non-B HIV subtypes (subtypes A, C, D, or G ) regardless of transmission:mode. Of these women, 21% infected with non-B HIV subtypes appeared to be infected by subtype chimeric viruses and 7% wer e jointly infected with viruses belonging to two different subtypes (A and C). Data demonstrate a preferential representation of non-B HN subtypes in women infected through heterosexual contact, as well as a high degree of re combination between viruses derived from endemic areas in which several HIV subtypes predominate. Combined with the increased incidence of heterosexua l transmission of HIV, the results imply that an increased subtype diversit y can be anticipated in newly infected individuals.