[Show abstract][Hide abstract] ABSTRACT: The potential for implementation of HIV vaccine trials in hard-to-reach female sex workers in an inner city area of Barcelona, Spain was assessed via a study of HIV risk, willingness to participate and the success of retention strategies. In 130 women, serological HIV status, behavioral risk exposures and willingness to participate in future HIV vaccine trials were recorded every six months using a confidential questionnaire. An enhanced retention (ER) strategy was compared with a control retention (CR) strategy comprising the recording of data on appointment cards. HIV seroincidence and retention rates were estimated. Retention rates after 6 and 12 mo of follow-up in the ER group were 76% and 69% respectively compared with 16% and 13% in the CR group. Among the ER group 97% were willing to participate in HIV vaccine trials at baseline and, after 12 mo of follow-up. Willingness was significantly associated with higher HIV risk exposure, and higher education level. Successfully retaining these cohorts over time in settings with a high HIV seroincidence rate is an ongoing challenge that will need to be addressed to ensure participation in future trials. Furthermore, as we have demonstrated, the fact that retaining hard-to-reach populations is difficult should not exclude this target population for HIV vaccine and prevention trials.
Full-text · Article · Jan 2013 · Human Vaccines & Immunotherapeutics
[Show abstract][Hide abstract] ABSTRACT: Being able to recruit high-risk volunteers who are also willing to consider future participation in vaccine trials are critical features of vaccine preparedness studies. We described data from two cohorts of injection- and non-injection drug users in Barcelona, Spain [Red Cross centre] and in San Francisco, USA, [UFO-VAX study] at high risk of HIV/HCV infection to assess behaviour risk exposure and willingness to participate in future preventive HIV vaccine trials. We successfully identified drug-using populations that would be eligible for future HIV vaccine efficacy trials, based on reported levels of risk during screening and high levels of willingness to participate. In both groups, Red Cross and UFO-VAX respectively, HCV infection was highly prevalent at baseline (41% and 34%), HIV baseline seroprevalence was 4.2% and 1.5%, and high levels of willingness were seen (83% and 78%).
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to assess HIV risk and willingness to participate in HIV vaccine trials in three high risk populations
in Spain. Eight hundred and forty-four participants, comprising female sex workers, injection and non-injection drug users
(IDUs and NIDUs, respectively), and men who have sex with men were tested for HIV and surveyed for risk and willingness to
participate in future preventive HIV vaccine trials. HIV seroprevalence was 3.8% (95%CI: 2–11). HIV infection was associated
with transgender identification, IDU in the past year, and sex with an IDU or other drug-using partner. The majority (82%)
expressed their willingness to participate in HIV vaccine trials. Substantial sexual and parenteral risk in all groups and
concomitant willingness to participate in vaccine trials was found, particularly among women and IDUs. Additional longitudinal
cohort studies in Spain are needed to plan future vaccine efficacy trials.
KeywordsHIV-Female sex workers-Men who have sex with men-Injection drug users-Vaccine preparedness studies
Full-text · Article · Jun 2010 · AIDS and Behavior