Rapid molecular epidemiology of human immunodeficiency virus transmission.

Close sequence homology between strains of HIV-1 have been used to corroborate cases of epidemiologically identified transmission. As an alternative to extensive DNA sequence analysis, genetic relateness between pairs of HIV quasispecies was estimated using the reduced electrophoretic mobilities of HIV-1 envelope DNA heteroduplexes through polyacrylamide gels. All six infections acquired in a dental practice in the late 1980s and four of six infections acquired through blood product transfusions and sexual contact in 1984-1985 could be rapidly identified. A rising level of genetic diversity within HIV-1 subtype B facilitated the detection of later transmission events. Transmission linkages could be detected up to 4 years following infection. The simple and rapid technique of DNA heteroduplex tracking can therefore assist epidemiological investigations of HIV transmission and potentially of other genetically variable infectious agents.