Retroviruses and reproduction revisited.

Thanks to effective anti-HIV medications, deaths from acquired immunodeficiency disease (AIDS) have plummeted, although the incidence of new HIV infections has decreased little, approximately 36,000 annually in the USA. The CDC estimates 1.1 million persons, mostly men, are living with HIV in the USA, with approximately 14% unaware they are infected. Since the global blood supply is essentially free of HIV today, infected semen is fueling the pandemic (88% of new infections in the USA), with needle sharing among IV drug abusers (7% of new US infections) and female to male transmission (5% of new infections) accounting for the balance. In spite of the importance to disease prevention and strategies for safe conception, semen transmission of HIV is not well understood. Because anti-HIV therapy does not eliminate HIV from semen, the Centers for Disease Control (CDC) for the past 25 years has espoused condom use as the safest approach to prevent HIV transmission, as well as other sexually transmitted diseases. A few months ago, however, an MMWR was circulated by the CDC that suggested condomless sex might be safe if the HIV-infected partner's medications achieved an undetectable viral load in his blood. This new opinion was based on reports by three teams of investigators cited in the MMWR: "All three studies observed no HIV transmission to the uninfected partner while the partner with HIV was virologically suppressed with ART." Unfortunately, this CDC statement does not fully describe the data presented in the studies, and abandoning condom use puts uninfected partners, including women seeking to conceive, at risk for infection by HIV and other STDs.