The results of a MenACWY-CRM vaccine extension study have been published in Elsevier, with Dr. Shane Christensen involved as a co-author. Enrollment included children 7-10 and 11-15 years of age, who received the vaccine in the original study five years earlier, and vaccine-naive children of the same age. About half of the originally vaccinated children retained protective antibodies for serogroups C, W and Y five years later. Less protection was found for serogroup A. With a positive booster response and no safety concerns, five years may be an appropriate time period between first vaccine and booster.
