A group of children under 3 years of age received an incorrect dosage of H1N1 vaccine on the evening of Monday, November 9. This only affected children under 3 years of age on Monday night. There have been no reports of significant adverse effects from the dosage and we don't anticipate any adverse effects. While the amount of dosage this group received was not the recommended dose for this age group, it was the same dosage used in studies sponsored by the National Institutes of Health for the age group. It is important to remember that the H1N1 vaccine is a low dose vaccine as compared to seasonal flu vaccines that children receive every year. The larger dose that was given on Nov. 9 still contains fewer antigens than a seasonal flu vaccine. If you have any questions or concerns, please call us at (651) 439-1234 and speak with one of our pediatric nurses.