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Ask the Experts


My new girlfriend just recently found out she is HIV positive. She is on medication and wants to have sex but does not want to use protection. She claims that she recently had a test run and it came back undetectable for HIV. What are the possible risks to me?

Answered by: Robert Remien

Generally speaking, the lower someone’s “viral load” (i.e., the amount of virus present in their blood), the less likely they are to transmit the virus to another person. However, “undetectable” viral load only means that the amount of virus is below the ability of the test to detect; there is always still some virus present and viral replication is always occurring.

Further, viral load levels can fluctuate due to many factors, such as the presence of another type of infection or a lapse in treatment. And while infection from a woman to a man through vaginal intercourse is not the most efficient mode of transmission, transmission risk can be higher due to other factors, such as if the man is uncircumcised or if the woman is menstruating.

This is a decision that you and your girlfriend will need to make (ideally in consultation with your physician) about how much risk you are comfortable with regarding HIV, as well as other sexually transmitted infections. Trust and communication are also important in gauging any type of risk within a couple, particularly a new couple.