BACKGROUND:
Routine infant hepatitis B vaccine (HBV) immunization has been recommended since 1991. To accelerate the uptake of this recommendation California added school entry requirements for HBV at kindergarten entry in 1997 and for 7th grade entry in 1999.

OBJECTIVE:
1. Assess HBV coverage for children aged 3-17 years in San Diego County.
2. Interpret differences in HBV coverage rates in relation to school entry requirements.
3. Suggest strategies to improve HBV coverage for teenagers and young adults.

METHOD:
The County of San Diego Immunization Program conducted a random digit dialing telephone survey in 2003 that included 1,455 children between 3-17 years of age. HBV immunization status was assessed as well as responses to KAB questions. Fifty-one percent of the children had data from vaccination records, and 49% from parents’ recall.

RESULT:
Using parent reports from vaccination records, all children born after 1994 (1994-2000) had coverage rates above 94% for HBV#3. Children born in 1991, 1992, and 1993 had HBV #3 coverage levels of 74%, 81%, and 88% respectively, while children born from 1987-1990 (thus directly affected by the 7th grade law) had coverage levels of 85-96%. The two oldest cohorts (1985, 1986) had coverage levels of 56% and 69%.

CONCLUSION:
The decline in HBV coverage in the 1991 to 1993 birth cohorts may be from children who entered school before implementation of the hepatitis B kindergarten/first grade law and who have not yet been affected by the 7th grade law. Based on these findings, it is recommended that the 7th grade school requirement remain in effect and be enforced by schools during the 2004-05 and 2005-06 school years.

LEARNING OBJECTIVES:
· Describe the long-term effectiveness of school entry laws on Hepatitis B vaccination level on adolescents and teenagers.
· Identify follow-up school record assessment strategies to assure long-term success of entry requirements.