Meningococcal conjugate vaccine uptake, measured by Michigan's immunization registry

To describe the uptake of meningococcal conjugate vaccine (MCV4) in Michigan adolescents following its approval in January 2005, and compare it to the use of meningococcal polysaccharide vaccine (MPSV4) in 2004.

All available records of meningococcal immunizations given between February 1986 and March 2006 were obtained from the Michigan Childhood Immunization Registry (MCIR), which is used by about 95% of Michigan immunization providers. During late 2005 and early 2006, these records were analyzed by immunization type, administration date, recipient age, and health care provider type (public or private).

The MCIR contained 63,253 meningococcal immunizations. A total of 15.2% were given in 2004, 68.8% in 2005, and 10.8% in 2006. In those years, most immunizations occurred in June, July, and August. In 2005, 85.2% were MCV4. In 2004, 17 to 18-year olds received nearly all meningococcal immunizations; in 2005, 11 to 16-year olds received 58.0% of them. Estimates of immunization coverage were 4.0% for 11 to 12-year olds, 3.4% for 13 to 16-year olds, 5.9% for 17 to 19-year olds, and 19% for freshmen entering college.

Compared to 2004, in 2005 there was a large increase in the number of doses administered, with more MCV4 than MPSV4. Patterns of immunization were consistent with the Advisory Committee on Immunization Practices (ACIP) recommendations. Coverage of Michigan adolescents is low, but increased in 2005 compared with 2004.