Article

Long-term persistence of transmitted HIV drug resistance in male genital tract secretions: implications for secondary transmission.

University of California, San Diego, La Jolla, CA 92093-0679, USA.
The Journal of Infectious Diseases (impact factor: 6.41). 09/2007; 196(3):356-60. DOI:10.1086/519164 pp.356-60
Source: PubMed

ABSTRACT Transmitted drug-resistant HIV slowly reverts in the blood to drug-sensitive virus. The environment of the male genital tract (MGT) may result in even slower rates of reversion to drug susceptibility.
We measured the decay of resistance in longitudinally collected blood and semen samples from 5 individuals newly infected with HIV containing resistance mutations to nonnucleoside reverse-transcriptase inhibitors (NNRTIs). We also investigated the sexual transmission of HIV to and from these participants.
In 3 of the 5 individuals, NNRTI resistance persisted in blood and semen throughout follow-up (mean, 296 days after the estimated day of infection [EDI]). In the other 2 individuals, NNRTI resistance persisted in blood and semen for 871 and 1179 days after the EDI; however, even after NNRTI resistance had fully reverted in blood, it remained readily detectable in semen. Two transmission groups were identified among these participants--one as the recipient partner and the other as the source partner.
Transmitted drug-resistant HIV, which persists in blood for years, may revert to wild type even more slowly in the MGT. This prolonged persistence in the MGT may contribute to the high prevalence rates of transmitted drug resistance.

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Keywords

5 individuals
 
drug resistance
 
drug susceptibility
 
drug-sensitive virus
 
estimated day
 
infection [EDI]
 
MGT
 
NNRTI resistance
 
nonnucleoside reverse-transcriptase inhibitors
 
participants
 
prolonged persistence
 
recipient partner
 
resistance mutations
 
reversion
 
semen samples
 
sexual transmission
 
slower rates
 
source partner
 
transmission groups
 
Transmitted drug-resistant HIV