The purpose of this study is to summarize the occurrence of incident serious medically attended events and events of interest up to 1 year following MenACWY-CRM vaccination administered as part of routine clinical care. This US FDA post-marketing commitment study is an open-label, descriptive, epidemiological safety surveillance study of MenACWY-CRM vaccine in subjects 2 to 10 years of age within a large US Healthcare Maintenance Organization. The 26 events of interest are events commonly evaluated in vaccine safety studies and include certain neurological, immunological, vascular, musculoskeletal and hematologic disorders. All events are collected retrospectively.

This is an observational study, vaccines administration and data that is collected is only as part of routine clinical care. Vaccinated subjects are not actively recruited.

Events of Interest: Diabetes Mellitus, Rheumatoid arthritis, Idiopathic Thrombocytopenic Purpura, Iridocyclitis, Acute glomerulonephritis, Nephrotic syndrome, Grave's disease, Autoimmune hemolytic anemia, Myasthenia Gravis, New onset asthma, Allergic urticaria, Anaphylaxis, Meningococcal Disease, Intentional Injury

Inclusion Criteria:

• Registered with the HMO for at least 6 months prior to vaccination.
• Between the ages of 2 and 10 years (inclusive - i.e. has not reached their 11th birthday) at the time of the vaccination.
• Received any MenACWY-CRM vaccination during the vaccination period at the participating centers.

Exclusion Criteria:

• None

The study population is selected from the Health Maintenance Organization population of the Kaiser Permanente Southern California (KPSC) HMO in Pasadena, CA, USA.