Comparing Local and State Recommended Vaccination Coverage Levels Utilizing Data from an Elementary School District In 2010, Varicella Active Surveillance Project (VASP), Antelope Valley (AV), California (CA)

Background:  In light of the pertussis epidemic in CA, evaluating adherence to the Advisory Committee on Immunization Practices (ACIP) recommended vaccine schedule is important.  The ACIP recommends that children 4-6 years of age receive a second dose of varicella vaccine (2-VV) and a fifth dose of DTaP, (5-DTaP) unless the 4^th dose was given on/after the child’s 4^th birthday.  In CA, the 2^nd VV and 5^th DTaP doses are not kindergarten entry requirements.

Objectives: 

• Evaluate vaccination coverage for 2-VV and 5-DTaP doses using school entry vaccine data.
• Compare local vaccination coverage with states requiring 2-VV and 5-DTaP doses for “up-to-date” vaccination status for kindergarten entry.

Methods:  Vaccination history was obtained from kindergarteners within one public school district in AV, CA from mandatory health forms from the 2010-2011 school year.  Local coverage rates were compared to published coverage levels taken from 2009-2010 School Entry Immunization Assessment Report documenting completion of 2-VV and 5-DTap doses.  “Up-to-date” vaccination status is defined as having completed the 2-VV and 5-DTaP vaccination series.

Results:  Of 2,162 kindergarteners, 1,965 (90.7%) students had 5-DTaP and 1,899 (87.7%) had 2-VV doses; 1,756 (81.1%) had documented completion of both vaccine series. Eleven (0.05%) students had personal belief exemptions; for 10 (0.05%) students no vaccine information was available. States with kindergarten entry requirements reported a mean 92.3% coverage (range: 85.4-99.7%) for 2-VV, and a mean of 94.2% (range: 87.4-99.7%) for 5-DTaP.

Conclusions:  Coverage for 2-VV and 5-DTaP doses was lower in AV than the average coverage in states requiring these vaccines for school entry and “up-to-date” vaccination status.  AV coverage rates may not be generalizable to other schools.  Although school entry laws are important for ensuring high coverage, active surveillance in the AV may have contributed to the high coverage for 2-VV in the absence of school entry laws.