HETEROSEXUAL HIV-1 TRANSMISSION AND VIRAL LOAD IN HEMOPHILIC PATIENTS

Only one fifth or fewer of the female sexual partners of HIV-l-infecte d men with hemophilia become infected. The risk factors associated wit h heterosexual transmission of HN-I are not well understood. To invest igate the hypothesis that HIV-1 viral load may be related to heterosex ual HIV-1 transmission, we measured HIV-1 RNA by polymerase chain reac tion (PCR) in frozen samples from 39 men with hemophilia and HIV-1 inf ection obtained between 20 and 62 months after HIV-1 seroconversion? d uring at least a 6-month relationship with a female sexual partner. Th e median time from the hemophilic viral load determination to the esti mated date of transmission to the female partner was 9 months (range, 4-41 months). The proportion of HIV-positive hemophilic men with >100, 000 HN RNA copies/ml was significantly higher in transmitters (TR) (3 of 5 [60%]), than in nontransmitters (NTR) (3 of 34 [9%]; p = 0.027). There were no differences between TR and NTR in age at seroconversion (32.4 years each), in time from seroconversion to AIDS (67 versus 79 m onths), in mean CD4 number (245/mu l versus 260/mu l); nor in the prop ortion who developed AIDS (4 of 5 [80%] versus 24 of 34 [71%]), These findings appear to suggest that high HIV viral load in HIV-infected he mophilic men increases the risk of HIV transmission to heterosexual pa rtners. Viral load determinations may be helpful in counseling hemophi lic couples regarding transmission to female partners.