Vaccination against hepatitis A in children aged 12 to 24 months [corrected].
BACKGROUND
Current hepatitis A vaccines are either licensed for children >2 years of age, as in the U.S. or Chile, or >1 year of age, as in Europe and other parts of the world. Recent recommendations for immunization against hepatitis A have included routine vaccination of children in areas or regions of higher endemicity. However, data on hepatitis A vaccination in toddlers aged between 1 and 2 years are scarce.


METHODS
This open clinical study investigated the reactogenicity and immunogenicity of two doses (0, 6-month schedule) of an inactivated hepatitis A vaccine (Havrix pediatric, Glaxco SmithKline Biologicals, Rixensart, Belgium) in 120 seronegative children aged 12-24 months.


RESULTS
Pain at the injection site and irritability were the most frequently reported local and general symptoms, respectively. No serious adverse events related to the study vaccine were reported. One month after the first dose, all but one subject had antibodies against hepatitis A with a GMT of 159 mIU/mL. After the booster dose, all had antibodies with a GMT of 2,939 mIU/mL.


CONCLUSIONS
Our data show that the inactivated hepatitis A vaccine was well tolerated by these toddlers and that the vaccine elicits a good immune response.
Abarca
K
K
Centro de Investigación Médica, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile. katia@med.puc.cl
Ibañez
I
I
Flores
J
J
Vial
P A
PA
Safary
A
A
Potín
M
M
D002675:Child, Preschool; D004890:Erythema / Q000209:etiology; D005260:Female; D005334:Fever / Q000209:etiology; D006506:Hepatitis A / Q000517:prevention & control*; D035922:Hepatitis A Antibodies; D022362:Hepatitis A Vaccines / Q000009:adverse effects / Q000276:immunology*; D006508:Hepatitis Antibodies / Q000096:biosynthesis* / Q000097:blood; D006801:Humans; D007117:Immunization, Secondary; D007223:Infant; D008297:Male; D010146:Pain / Q000209:etiology; D015164:Vaccines, Inactivated / Q000009:adverse effects / Q000276:immunology
D035922:Hepatitis A Antibodies; D022362:Hepatitis A Vaccines; D006508:Hepatitis Antibodies; D015164:Vaccines, Inactivated