Antiretrovirals to prevent HIV infection: Pre-and postexposure prophylaxis

Division of Infectious Disease, University of North Carolina at Chapel Hill, 130 Mason Farm Road, CB #7030, Chapel Hill, NC 27599, USA.
Current Infectious Disease Reports (Impact Factor: 1.68). 08/2008; 10(4):323-31. DOI: 10.1007/s11908-008-0052-5
Source: PubMed

ABSTRACT More than 3 million people are now receiving antiretroviral therapy (ART) worldwide. Currently, the indications for ART depend primarily on CD4 count, blood viral burden, and clinical signs and symptoms suggesting advanced HIV disease. However, interest is increasing in ART's preventive potential. Postexposure prophylaxis following both occupational and nonoccupational exposure to HIV is the standard-of-care in many settings. Observational and ecologic studies suggest that ART administered to HIV-infected people reduces transmission within serodiscordant couples. Pre-exposure prophylaxis to prevent HIV infection is a potentially safe and intermittent intervention for very high-risk people, and clinical trials to evaluate this preventive strategy are underway. The prevention benefits of ART may begin to affect the decision of when to start therapy and add a much-needed strategy to current HIV prevention efforts.

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Available from: Cynthia L Gay, Sep 28, 2015
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    • "HIV viral load is the key determinant of viral transmission, as demonstrated clearly in observational studies of sexual transmission among HIV-discordant couples; in those studies, no transmission was seen when the index case had a plasma viral load below 1,000 copies HIV ribonucleic acid (RNA)/mL [25,26]. By reducing plasma viral load to undetectable levels (<50 copies HIV RNA/mL), it is assumed that ART will also suppress viral burden in the genital tract to levels at which transmission is unlikely to occur [27,28], although genital shedding of HIV can sometimes occur even when plasma viraemia is suppressed [29]. While vertical HIV transmission occurs via a different route, proof of concept is provided by trials of PMTCT, which have demonstrated that HIV transmission from mother to child before, during, or after delivery is largely prevented by ART [10-12]. "
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