Kids Need 2 H1N1 Vaccine Shots, Study Shows

November 3, 2009

Children 9 years of age and younger have a much stronger immune response when they receive a second dose of 2009 H1N1 influenza vaccine, according to preliminary study results released by the NIH.

Children 9 years of age and younger have a much stronger immune response when they receive a second dose of 2009 H1N1 influenza vaccine, according to preliminary study results released by the NIH.

This study includes 583 children who are currently enrolled at centers throughout the United States. A second 15-mcg dose of vaccine elicited a robust immune response after 8 to 10 days in those aged 6 months through 9 years, a significant improvement over the immune responses in this age group following only a single dose.

These findings support the current recommendation of the Advisory Committee on Immunization Practices: To achieve an immune response likely to protect from illness, children 9 years of age and younger should receive two 15-mcg doses of 2009 H1N1 vaccine. The trial data also continue to support the recommendation that persons 10 years of age and older-including pregnant women-should receive only one 15-mcg dose of vaccine.