Systematic review of orogenital HIV-1 transmission probabilities
File(s)
Author(s)
Baggaley, RF
White, RG
Boily, M-C
Type
Journal Article
Abstract
Background The objective was to assess the risk of HIV transmission from orogenital intercourse (OI).
Methods Systematic review of the literature on HIV-1 infectiousness through OI conducted according to MOOSE guidelines for reviews of observational studies. The PubMed database and bibliographies of relevant articles were searched to July 2007.
Results Of the titles, 56 214 were searched from which 10 potentially appropriate studies were identified; two additional studies were identified through bibliographies and one through discussion with experts. There were 10 included studies, providing estimates of transmission probabilities per-partner (n = 5), incidence per-partner (n = 3), per-study participant (n = 3, following initially seronegative individuals whose partners are of unknown serostatus) and per-act (n = 3). Only four of 10 studies reported non-zero estimates: two per-partner estimates (20%, 95% CI: 6–51, n = 10 and a model-based estimate, 1%, range 0.85–2.3%), one per-study participant estimate (0.37%, 95% CI: 0.10–1.34%) and one per-act estimate (0.04%, 95% CI: 0.01–0.17%). Upper bounds for the 95% CI for zero estimates tended to be relatively large due to the small study sample sizes: 9.0, 12.1 and 2.8% for per-partner; 4.7, 9.6 and 1.8 per 100 person-years for incidence per-partner; 4.4% per-study participant and 0.45 and 0.02% for per-act. Given the small number of studies, a meta-analysis was not considered appropriate.
Conclusions There are currently insufficient data to estimate precisely the risk from OI exposure. The low risk of transmission evident from identified studies means that more and larger studies would be required to provide sufficient evidence to derive more precise estimates.
Methods Systematic review of the literature on HIV-1 infectiousness through OI conducted according to MOOSE guidelines for reviews of observational studies. The PubMed database and bibliographies of relevant articles were searched to July 2007.
Results Of the titles, 56 214 were searched from which 10 potentially appropriate studies were identified; two additional studies were identified through bibliographies and one through discussion with experts. There were 10 included studies, providing estimates of transmission probabilities per-partner (n = 5), incidence per-partner (n = 3), per-study participant (n = 3, following initially seronegative individuals whose partners are of unknown serostatus) and per-act (n = 3). Only four of 10 studies reported non-zero estimates: two per-partner estimates (20%, 95% CI: 6–51, n = 10 and a model-based estimate, 1%, range 0.85–2.3%), one per-study participant estimate (0.37%, 95% CI: 0.10–1.34%) and one per-act estimate (0.04%, 95% CI: 0.01–0.17%). Upper bounds for the 95% CI for zero estimates tended to be relatively large due to the small study sample sizes: 9.0, 12.1 and 2.8% for per-partner; 4.7, 9.6 and 1.8 per 100 person-years for incidence per-partner; 4.4% per-study participant and 0.45 and 0.02% for per-act. Given the small number of studies, a meta-analysis was not considered appropriate.
Conclusions There are currently insufficient data to estimate precisely the risk from OI exposure. The low risk of transmission evident from identified studies means that more and larger studies would be required to provide sufficient evidence to derive more precise estimates.
Date Issued
2008-07-29
Date Acceptance
2008-06-23
Citation
International Journal of Epidemiology, 2008, 37 (6), pp.1255-1265
ISSN
1464-3685
Publisher
Oxford University Press
Start Page
1255
End Page
1265
Journal / Book Title
International Journal of Epidemiology
Volume
37
Issue
6
Copyright Statement
© The Author 2008. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited.
License URL
Subjects
Science & Technology
Life Sciences & Biomedicine
Public, Environmental & Occupational Health
PUBLIC, ENVIRONMENTAL & OCCUPATIONAL HEALTH, SCI
HUMAN-IMMUNODEFICIENCY-VIRUS
ORAL SEX
HOMOSEXUAL MEN
LESBIAN SEX
RISK
INFECTION
SEROCONVERSION
EPIDEMIOLOGY
POPULATION
PARTNERS
Female
HIV Infections
HIV-1
Humans
Male
Probability
Sexual Behavior
Unsafe Sex
Epidemiology
0104 Statistics
1117 Public Health And Health Services
Publication Status
Published