Will sexual risk behaviour increase after being vaccinated for AIDS?

The question of whether people will engage in greater levels of HIV-associated risk behaviour after receiving an AIDS vaccine has not been sufficiently investigated. Three objectives were: (1) assess the likelihood that people will engage in greater levels of HIV-risk behaviour after receiving an AIDS vaccine; (2) determine the association of increases with vaccination intent; and (3) identify differences between people who would and would not increase their HIV-risk behaviour after vaccination. A cross-sectional survey was conducted of 278 adults from three populations: gay men, African-American women, and persons who used illicit drugs. Nearly one-quarter of the sample indicated a likelihood that their HIV-risk behaviour would increase after vaccination. This increase was positively associated (r = 0.24) with increased intent to be vaccinated. Previous worry about having HIV (adjusted odds ratio [AOR] = 3.4, P = 0.004), being 32 years of age or older (AOR = 2.9, P = 0.0007), and having less than a high school education (AOR = 2.3, P = 0.027) were each associated with a post-vaccination increase in HIV risk. With the seemingly real potential for increased HIV-risk behaviours after being vaccinated against AIDS, intervention studies are warranted to identify strategies with potential to minimize this phenomenon.