Display Settings:

Format

Send to:

Choose Destination
We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Am J Epidemiol. 1998 Jul 1;148(1):88-96.

Heterosexual transmission of human immunodeficiency virus: variability of infectivity throughout the course of infection. European Study Group on Heterosexual Transmission of HIV.

Author information

  • 1European Centre for the Epidemiological Monitoring of AIDS, Saint-Maurice, France.

Abstract

Although individuals infected with human immunodeficiency virus (HIV) seem to be more infectious in the late stages of HIV infection and possibly also during the seroconversion period, most estimates of per-sexual-contact infectivity have been obtained without allowing for variability over the course of infection. In this analysis, a probabilistic model was fitted to data from a European study carried out between 1987 and 1992 that involved 499 (359 males and 140 females) HIV-infected subjects (index cases) and their regular heterosexual partners. The model used allowed infectivity (the per-sexual-contact HIV transmission probability, mu) to vary through three stages: the first 3 months following infection, the subsequent asymptomatic period, and the advanced stage (HIV-related clinical symptoms or a CD4-positive T lymphocyte count less than 200/mm3). Male-to-female infectivity through penile-anal sex was found to be higher in both the early and advanced stages of infection (mu=0.183) than in the longer intermediate period (mu=0.014) (p < 0.03). Failure to demonstrate significant differences between stages for other types of contact (male-to-female penile-vaginal contacts: mu=0.0007; female-to-male transmission: mu=0.0005) may reflect insufficient power rather than a true lack of variability. Indeed, the results for penile-anal sex suggest that persons who are in the process of seroconverting may be much more infectious than asymptomatic infected persons, whatever the type of contact. Prevention education should stress the risk of HIV transmission from subjects who may be unaware of their infection.

PMID:
9663408
[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk