The Texas Child Care Immunization Assessment Survey March 7, 2007 National Immunization Conference Julie Townsend, MS

Immunization Requirements In Texas, children attending licensed child care facilities required to have age appropriate vaccination with most ACIP Recommended Vaccines Includes hepatitis A and pneumococcal vaccines No requirements for rotavirus or influenza In Texas, children enrolled in child care facilities (including registered child care homes), pre-kindergarten, or early childhood programs must have age-appropriate vaccination against diphtheria, pertussis, tetanus, polio, Haemophilus influenzae type b, measles, mumps, rubella, hepatitis B, varicella, hepatitis A, and pneumococcal disease. Requirements for hepatitis A and pneumococcal vaccines went into effect in September 1, 2005.

Age Appropriate Vaccination Age appropriate vaccination example: By 3 months, a child should have received 1 DTaP, 1 Hib, 1 polio, 1 hepB, and 1 PCV.

Child Care Facilities 8,788 licensed child care centers 7,513 registered child care homes Source: Texas Department of Family and Protective Services, Child Care Licensing Based on capacity size data, 90% of children at child care facilities go to licensed child care centers.

Background Prior to 2005, vaccination coverage levels calculated from child care audit data Collected for all age groups 25% of child care facilities audited every year Standardized form, but variability in data collection methods Resource intensive Prior to 2005, vaccination coverage levels among child care attendees were calculated from data collected during routine child care audits. Every year, 25% of child care facilities were audited by local health department staff. Immunization records of all child care attendees were reviewed. Although a standardized form was used, variability existed in data collection methods. Some auditors reported coverage levels from follow-up visits after educating child care staff to bring children up-to-date for their age. In the fall of 2005, the need arose for a new methodology to assess vaccination coverage among child care attendees 19 – 59 months of age.

Objective To develop a new survey methodology to assess vaccination coverage levels of child care attendees 19 – 59 months of age A methodology was developed that wouldn’t be so resource intensive and would provide better estimates of vaccination coverage among child care attendees 19 – 59 months of age.

Methods Referred to Immunization Program Operations Manual – Population Assessments Zell Manual, 1990 Stratified cluster sampling design Sampling Procedures for Conducting Immunization Assessments/Validation Surveys for School and Day Care Centers, Retrospective Surveys Using School Systems Databases and Guidelines for Public Health Immunization Clinic Audits for Immunization Project Areas, Appendix 2

Texas Stratified Sampling Design – strata consisting of 8 health service regions (1, 2&3, 4&5N, 6&5S, 7, 8, 9&10, 11)

Methods, Cont. Modified parameters for sample size and number of facilities selected (clusters) 80% coverage levels assumed ±3% margin of error “clustering coefficient” set at 2.5 n = 1,708 per strata (region) 100 child care facilities selected per strata (region)

Sampling Plan Probability proportional to size (pps) random sampling of facilities Size based on capacity, no enrollment data 100 facilities selected per region 20 child immunization records randomly selected (or total enumeration if < 20) Data files on child care facilities were obtained from the Texas Department of Family and Protective Services, Child Care Licensing. Sampling of child care facilities conducted using SAS. Only children 19 – 59 months of age on the survey date were eligible for inclusion in the survey.

Data Collection Lists of selected facilities and survey instructions mailed to the Health Service Regions (HSRs) and distributed to local health departments Data collection conducted primarily by child care audit staff DOB, all immunizations and dates, exemptions collected

Data Collection Software - CASA Although CASA was designed to assess provider immunization rates, we also use it as a data management tool to collect immunization data for our population assessments. However, all data analysis activities are conducted in SAS software.

Data Analysis Conducted using SAS and SUDAAN Weighted coverage level estimates for state, HSR Estimates by vaccine, 4:3:1, 4:3:1:3:3, 4:3:1:3:3:1, 4th DTaP by 19 months 4 DTaP, 3 polio, 1 MMR, 3-4 Hib*, 3 HepB, 1 varicella, 4 PCV*, 2 HepA (*age dependent) If a child started the series late, he or she may not require all doses of Hib and PCV.

Vaccination Coverage Levels Among Child Care Attendees, Texas 2005 Hib vaccination coverage is unusually low since data on this vaccine was not consistently collected in two regions. Varicella vaccination coverage is unadjusted for disease history. Only two vaccines have coverage of at least 95% (polio and MMR).

Select Results – Hib and PCV Coverage with 3 doses of Hib and 3 doses of pneumococcal vaccine, regardless of dosage intervals and timing, was higher than coverage levels in accordance with ACIP age appropriate vaccination and intervals. Some children starting these series on time were missing the booster dose.

Select Results – HepA Statewide, only about 25% of children aged 24 – 59 months in childcare completed the hepatitis A vaccine series. Nearly two thirds had received the 1st dose. In high disease incidence and U.S./Mexico border counties where vaccination was mandated for childcare attendance (40 counties), coverage was higher but less than expected.

Summary Vaccination coverage among child care attendees was slightly lower than expected Improvement needed for DTaP, Hib, PCV, and HepA Confusion over vaccine requirements and record keeping potential issues Sample size not met in most regions

Lessons Learned Be organized Staff trained on software Clear instructions and expectations

Feasibility Time-consuming Provides more accurate estimates of vaccination coverage levels Possible to do additional analyses looking at age appropriate vaccination, etc.

Julie.Townsend@dshs.state.tx.us (512) 458-7111 ext. 3949 Contact Information Julie.Townsend@dshs.state.tx.us (512) 458-7111 ext. 3949