Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2014 Jun 19;28(10):1509-19.
doi: 10.1097/QAD.0000000000000298.

Estimating per-act HIV transmission risk: a systematic review

Pragna Patel  1 , Craig B Borkowf, John T Brooks, Arielle Lasry, Amy Lansky, Jonathan Mermin
Affiliations

Estimating per-act HIV transmission risk: a systematic review

Pragna Patel et al. AIDS. .

Abstract

Background: Effective HIV prevention programs rely on accurate estimates of the per-act risk of HIV acquisition from sexual and parenteral exposures. We updated the previous risk estimates of HIV acquisition from parenteral, vertical, and sexual exposures, and assessed the modifying effects of factors including condom use, male circumcision, and antiretroviral therapy.

Methods: We conducted literature searches to identify new studies reporting data regarding per-act HIV transmission risk and modifying factors. Of the 7339 abstracts potentially related to per-act HIV transmission risk, three meta-analyses provided pooled per-act transmission risk probabilities and two studies provided data on modifying factors. Of the 8119 abstracts related to modifying factors, 15 relevant articles, including three meta-analyses, were included. We used fixed-effects inverse-variance models on the logarithmic scale to obtain updated estimates of certain transmission risks using data from primary studies, and employed Poisson regression to calculate relative risks with exact 95% confidence intervals for certain modifying factors.

Results: Risk of HIV transmission was greatest for blood transfusion, followed by vertical exposure, sexual exposures, and other parenteral exposures. Sexual exposure risks ranged from low for oral sex to 138 infections per 10,000 exposures for receptive anal intercourse. Estimated risks of HIV acquisition from sexual exposure were attenuated by 99.2% with the dual use of condoms and antiretroviral treatment of the HIV-infected partner.

Conclusion: The risk of HIV acquisition varied widely, and the estimates for receptive anal intercourse increased compared with previous estimates. The risk associated with sexual intercourse was reduced most substantially by the combined use of condoms and antiretroviral treatment of HIV-infected partners.

PubMed Disclaimer

Conflict of interest statement

Conflicts of interest

There are no conflicts of interest.

Figures

Fig. 1
Fig. 1
(a) Selection of studies regarding per-act HIV-1 transmission probabilities. (b) Selection of studies regarding factors that modify HIV transmission risk.
Fig. 2
Fig. 2
Per-act HIV-1 transmission risk of anal and vaginal intercourse and the modifying effects of antiretroviral treatment for the HIV-infected partner and condom use on the per-act HIV transmission risk estimates.
See this image and copyright information in PMC

References

    1. CDC. Antiretroviral postexposure prophylaxis after sexual, injection-drug use, or other nonoccupational exposure to HIV in the United States: recommendations from the U.S. Department of Health and Human Services. Morb Mortal Wkly Rep. 2005;54(RR–2):1–20. - PubMed
    1. Varghese B, Maher JE, Peterman TA, Branson BM, Steketee RW. Reducing the risk of sexual HIV transmission: quantifying the per-act risk for HIV on the basis of choice of partner, sex act, and condom use. Sex Transm Dis. 2002;29:38–43. - PubMed
    1. Leynaert B, Downs AM, De Vincenzi I European Study Group on Heterosexual Transmission of HIV. Heterosexual transmission of HIV: variability of infectivity throughout the course of infection. Am J Epidemiol. 1998;148:88–96. - PubMed
    1. European Study Group on Heterosexual Transmission of HIV. Comparison of female to male and male to female transmission of HIV in 563 stable couples. Br Med J. 1992;304:809–813. - PMC - PubMed
    1. Baggaley RF, Boily MC, White RG, Alary M. Risk of HIV-1 transmission for parental exposure and blood transfusion: a systematic review and meta-analysis. AIDS. 2006;20:805–812. - PubMed

Publication types