ABSTRACT. Objective. To determine hepatitis A vaccination coverage and factors associated with not receiving hepatitis A vaccine among children.Methods. A random cluster sample survey was conducted of parents of children who attended kindergarten in Butte County, California, in 2000. Because of a history of recurrent epidemics, an aggressive hepatitis A vaccination program was ongoing during the time this study was conducted. Receipt of 1 or 2 doses of hepatitis A vaccine was studied.Results. Of 896 surveys sent, 648 (72%) were completed. The vaccination coverage for at least 1 dose of hepatitis A vaccine was 398 (62%) and for 2 doses was 272 (42%). Factors associated with not receiving the vaccine included lack of provider recommendation (vs having recommendation; odds ratio [OR]: 7.8; 95% confidence interval [CI]: 4.9 -12.2), not having heard of the vaccine (OR: 2.4; 95% CI: 1.2-4.9), and parent's not perceiving child is likely to get hepatitis A (vs perceiving child might get disease; OR: 2.1; CI: 1.6 -2.9).Conclusions. Vaccination coverage among kindergartners did not reach high levels (ie, >90%), despite aggressive vaccination efforts in this community. Lack of provider recommendation and lack of parental awareness of hepatitis A vaccine were the 2 most significant factors associated with failure to receive vaccine. These findings will facilitate the development of vaccination strategies for communities in which hepatitis A vaccination is recommended. unpublished data, 2002). Because of clinically unrecognized or asymptomatic infections, especially among children, the number of infections may be up to 10 times higher. 1 Because children account for at least one third of cases and also are a potential source of infection for others, routine vaccination of children is likely to be an effective way to reduce hepatitis A incidence. 2 In October 1999, the Advisory Committee on Immunization Practices (ACIP) updated recommendations for hepatitis A vaccination to include routine vaccination of children age Ն2 years in states, counties, and communities with hepatitis A incidence rates that were at least twice the 1987-1997 national average (Ն20 cases per 100 000 population). 2 Over time, this strategy has the potential to substantially lower disease incidence and possibly eliminate indigenous transmission of hepatitis A virus. 3 Butte County is located in the Sacramento Valley of northern California and had an estimated population in 2000 of 207 000. The county has had recurrent outbreaks since hepatitis A became reportable in 1966 and meets the ACIP's criteria for routine childhood hepatitis A vaccination. 4 During 1987-1997, the average annual hepatitis A incidence rate was 45.3 per 100 000 (CDC, unpublished data, 2001).From January 1995 through December 2000, a demonstration project was implemented in Butte County to assess the impact of routine vaccination of children on disease incidence over time. Hepatitis A vaccine was made widely available free of charge to children aged 2 to 12 years in 1995 and to succes...