The purpose of the study is to see which of the three current provincial Meningococcal C Conjugate vaccine schedules in Canada provide the longest lasting protection against Meningococcal C disease and to see if a booster vaccination is needed.

In 2002-2005, Canada introduced universal MenC programmes consisting of 1,2 or 3 infant doses. Most are one (12 mth) dose. High rates of serogroupC disease in 2000 and 2001 prompted some provinces to launch universal MenC vaccination programmes in 2002. The goal was to provide protection in infancy and early childhood (the time of most risk) with the hope that the protection would extend throughout adolescence (the second highest risk). It is unclear if early multi-dosing or 1 dose programmes would offer better protection (lack of data). Each province in Canada has chosen different Meningococcal C Conjugate vaccine provision schedules for the primary vaccinations.

This study will look at short term protection after the differing provincial series of vaccinations has been given and compare those who do not get primary vaccination under 1 year of age (NS) with two schedules of primary immunization (BC at 2 and 4 mths and Alberta at 2 months). A blood sample will be collected at 12-13 mths for this comparison. A booster vaccination of the current provincial Men C vaccine will be provided at 12 months. Another blood sample will be collected 1 mth later to look at the difference in responses between the groups (different provincial primary vaccination schedule). 2 years and 4 years later (at age 3 and age 5), another blood sample will be collected to look at the difference in long term protection of the groups where the primary schedule was different.

Inclusion Criteria:

• 12-13 mths of age
• over 34 weeks gestation
• healthy children
• having had all vaccinations of Meningococcal C vaccine per the recommended schedule for their respective province within a month of the recommended age - documented.
• Communication in English

Exclusion Criteria:

• No contraindication to receiving 12 mth dose of MenC vaccine
• No other MenC vaccine or MenC disease