The purpose of this study is to compare the effects of (a) immunization setting and (b) outreach worker support on young injection drug users' (IDU) adherence to a multiple dose immunization schedule with a combined hepatitis A virus (HAV) inactivated and hepatitis B virus (HBV) recombinant vaccine.
This is a research trial consisting of a cross-sectional screening study and a prospective cohort study (randomized, 2x2 factorial design). The primary aim of the study is to evaluate the effects of immunization setting and outreach worker support on young IDU's adherence to a multiple dose immunization schedule with a combined HAV and HBV vaccine. Secondarily, the study will 1) explore the feasibility of a remote immunization network and web-based vaccine registry to improve immunization coverage of transient young IDU, 2) examine the effect of hepatitis C virus (HCV) infection in vaccine effectiveness, and 3) assess behavior change and vaccine attitudes in young IDU participating in a preventive vaccine trial. Subjects in the screening study complete an interview, receive counseling and testing for HIV, HAV, HBV and HCV, and return in one week for test results and risk reduction counseling. Subjects eligible for the cohort study receive their first immunizations at enrollment and then are randomized to receive subsequent vaccines at either a set of syringe exchange programs (SEP) or at a public health adult immunization clinic (AIC). Subjects also are randomized to receive vaccine reminders from an outreach worker or no outreach worker support. Each subject receives a total of 4 immunizations over 6 months. Follow up visits include interviews, counseling, and viral testing. Study participation is for 12 months.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
NONE
Enrollment
546
Each subject will receive a total of 4 immunizations over 6 months on a 0-1-2-6 month schedule. At the initial visit, subjects\>18 years of age will receive the Twinrix vaccine and subjects\<18 years of age will receive the Engerix-B vaccine. Cohort subjects\>18 years found to have HAV antibody at screening will receive Engerix-B for their remaining 3 immunizations. All subjects will receive: an immunization record with the first vaccine dose entered and the dates the next doses are due; helpful hints for remembering vaccine appointments; and written instructions on where and how to get immunized outside of SF.
Outreach worker vaccine adherence support: Half of cohort subjects will be assigned to outreach worker vaccine adherence support and will meet with their outreach workers from Haight Ashbury Youth Outreach Team (HAYOT) and Glide Health Services on the day of vaccine cohort study enrollment. Intensive vaccination tracking and in-person outreach support will begin one week before the second and third vaccine doses are due, and again two weeks before the fourth dose is due.
University of California San Francisco Medical Cen
San Francisco, California, United States
Vaccine Series Completion
The primary outcome was the completion of the four-dose vaccine series in a 12 month period.
Time frame: 12 months
Hepatitis B Surface Antibody Seroconversion After 3 Vaccine Doses
To examine the effect of hepatitis C virus (HCV) infection on vaccine effectiveness, we compared anti-HBs (antibody to the hepatitis B surface antigen) seroconversion after three vaccine doses between anti-HCV (antibody to the hepatitis C virus) positive and anti-HCV negative participants.
Time frame: 12 months
Viral Transmission Risk Behavior Association With Travel
In a cross-sectional analysis of 355 subjects enrolled between 2004 and 2006, we estimate the associations between travel in the 3 months prior to baseline and behaviors occurring in the 30 days prior to baseline, such as drug and alcohol and sexual behaviors, that may facilitate the spread of viral infections.
Time frame: Baseline
HIV Vaccine Trial Willingness
We assessed knowledge about vaccine trials and willingness to participate in preventive HIV vaccine trials by asking the question: "How willing would you be to join a study of a vaccine to prevent HIV infection, if the study were to start tomorrow?". Willingness was measured on a 4-point response scale, ranging from 1 (Definitely not willing) to 4 (Definitely willing).
Time frame: Baseline
HIV Vaccine Trial Knowledge
Participants were asked if they agreed or disagreed with or were unsure of each of eight statements about HIV vaccine trial concepts from the HIV Network for Prevention Trials (HIVNET). 1. Preventive HIV vaccine studies enroll people who are HIV-positive and HIV-negative. 2. Some participants in HIV vaccine studies will get a real vaccine, and some will get a placebo (an inactive substance). 3. Only vaccines known to be at least 50% effective at preventing HIV are tested in HIV vaccine studies. 4. Once a large scale HIV vaccine study begins, we can be sure the vaccine is completely safe. 5. Participants are told whether they got the HIV vaccine or the placebo at the end of HIV vaccine studies. 6. HIV vaccines will never affect a person's HIV test results. 7. An HIV vaccine can infect a person with HIV disease. 8. People in vaccine studies know whether or not they got the placebo because only the vaccines cause side effects.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
The Adult Immunization Clinic (AIC) is a public low-cost vaccine clinic located centrally at 101 Grove Street in the lobby of the San Francisco Department of Public Health (SFDPH). The clinic is open from Monday-Friday 9 a.m. to 4 p.m. Nurses at the AIC will be available 40 hours/week to administer free immunizations to study subjects.
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6. Research nurses will provide 16 hours/week of vaccine administration services at SEPs well attended by young IDU. The San Francisco Needle Exchange (SFNE) serves primarily youth and young adults on Mondays, Wednesdays, and Fridays from 5-7 p.m. in an indoor location in the Haight-Ashbury district. A study nurse will be at SFNE for a total of 6 hours per week. HIV Prevention Project (HPP) sites also operate for 2 hrs each (Tues, Thu, Fri, Sat). Medical services are provided either in a clinic setting at indoor sites (6th Street) or at outdoor sites (Hemlock Alley, Duboce). A study nurse will attend each of these 5 weekly sites for a total of 10 hours/week.
Time frame: Baseline