Long-term immunity after two doses of inactivated hepatitis A vaccine, in Argentinean children.

We examined long-term anti-hepatitis A virus antibody persistence in Argentinean children 10 years after the initial study in which they received 2 doses of inactivated hepatitis A vaccine (Avaxim 80U). Of the 111 children, 48 from the initial trial were enrolled. Of 48, 47 (97.9%) participants had serum anti-hepatitis A virus antibody titers > or =20 mIU/mL, with the geometric mean concentration of 390.91 (+/-370.14) mIU/mL; (95% confidence interval, 282.2-499.5 mIU/mL), range, 36 to 1860.