KEYWORDS:
monovalent, bivalent and vaccination acceptance

BACKGROUND:
During 2001, the Illinois Department of Public Health (IDPH) implemented six viral hepatitis integration projects (VHIPs), each offering hepatitis A and B vaccination services to at-risk clients: injectable drug users (IDUs) and men having sex with men (MSMs). Vaccination acceptance rates among eligible clients were low with monovalent vaccines: 46 percent of MSMs and 40 percent of IDUs accessed hepatitis B vaccination while 33 percent of MSMs and 20 percent of IDUs accessed hepatitis A vaccination. Bivalent vaccine (Twinrix®) was purchased to try to increase vaccination acceptance among members of these target populations.

OBJECTIVE(S):
Monitor and compare target population acceptance rates for hepatitis A and B vaccination with monovalent and bivalent products to identify most productive vaccine strategy for VHIP initiatives.

METHOD(S):
All six VHIPs will be provided supplies of bivalent vaccine to use with unvaccinated clients from the at-risk populations during 2002. Clients who began vaccination in 2001 will continue their series with monovalent products. Data on all VHIP clients accessing vaccination services are reported monthly on an Excel spreadsheet, which identifies product information and vaccination dates. Vaccination data is linked with data from the client-completed behavioral risk assessment survey. These data will be evaluated to compare the target populations’ acceptance rates with use of monovalent and bivalent products.

RESULT(S):
Comparative data will be available by the end of the first quarter 2002. It is expected that acceptance rates by both at-risk populations will increase with use of the bivalent vaccine.

CONCLUSIONS(S):
Data will be utilized to determine vaccine strategies best tolerated by clients eligible for VHIP services.

LEARNING OBJECTIVES:
Describe how the availability of bivalent vs. monovalent vaccines impact adult acceptance of hepatitis A and B vaccination.