Dear Dr. Frascino: I have a hypothetical question: If one Poz'r was to have unprotected sex with another (both long-term, say 15 years Poz) and BOTH are on the EXACT same HAART regimines (and monogamous), Say Combivir, Sustiva, and Viread, would this greatly reduce, if not eliminate the possibility or re-infection, be it the same strain or not? Are the risks of developing resistance lessened any or eliminated? Logic seems to dictate that if both are on the same meds and have and are responding effectively, then whatever strain one has, the other's system would be able to "cope" due to the same meds. Opinion? And thank you so much for taking the time to answer all of our queries! God bless you!

Hi,

Hypothetical questions are always difficult to answer, because they rarely take into account all the confounding variables. In the case you suggest, for instance, confounding variables could include compliance with medications, concurrent STDs or OIs, plasma viral load, genital secretions (semen, cervical secretions), genetic susceptibility to various viral strains or subtypes, monogamous partners who for whatever reason turn out not to be so monogamous, etc., etc., etc. Consequently even serosorting within the parameters you hypothesize cannot be relied on to eliminate the possibility of reinfection. What we do know is that pozzies who drive their plasma viral loads down to undetectable levels significantly decrease the risk of transmitting their infections to others.

Stay safe. Stay well.

Dr. Bob