Abstract: The incidence of viral hepatitis A has decreased significantly in recent years in China due to the improvement of people's living standard and the promotion of vaccination for viral hepatitis A. However, outbreak of viral hepatitis A recently in California in the United States has reminded us the complexity and great challenges in the prevention of viral hepatitis A. The prevention of viral hepatitis A is still long-term existed, complex and arduous. This paper reviews the epidemic situation of viral hepatitis A in California within 1 year, analyzes its possible causes, and puts forward some measures of the prevention of viral hepatitis A, including the promotion of vaccination for viral hepatitis A, strengthening to the public health campaign, strengthening to tealth inspection and quarantine of food and strengthening to the study of epidemiology of viral hepatitis A. The vaccination for viral hepatitis A is the most economical and effective measures in the prevention of viral hepatitis A.

Key words: Viral hepatitis A, Epidemic, Prevention