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 ≥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.
From the *Infectious Diseases Program, Hospital de Niños “Dr. Ricardo Gutiérrez,” Buenos Aires, Argentina; †Laboratory of Virology, Hospital de Niños “Dr. Ricardo Gutiérrez,” Buenos Aires, Argentina; and ‡Sanofi Pasteur, Buenos Aires, Argentina.
Accepted for publication January 13, 2010.
Reprints: Eduardo L. López, MD, Guido 2676, Piso 10, 1425 Buenos Aires, Argentina. E-mail: firstname.lastname@example.org.