Immunization coverage and predictive factors for complete and age-appropriate vaccination among children of preschool age

Background and aims:To assess immunization coverage and identify factors influencing complete and age appropriate vaccination among children attending public nurseries in the municipal Athens area, following a full reimbursement policy (since 2008 for MCC, PCV7, varicella and hepatitis A vaccines).Methods:A cross-sectional study, using stratified sampling was performed during 2009-2011. Immunization history was obtained from vaccination booklets while demographic and socioeconomic characteristics along with parental attitudes towards immunization by telephone interviews. Percentages of vaccination were estimated by sample weighted proportions while associations between complete and age-appropriate vaccination and possible determinants by logistic regression analysis.Results:A total of 731 children (mean age: 46, median: 48, range: 10-65 months) were included (participation rate: 81.6%). Complete vaccination coverage was satisfactory overall, exceeding 90% for traditional antigens (DTP, polio, Hib, hepatitis B, 1st dose of MMR) but ranging between 61-92% for newly reimbursed vaccines. However, immunization was significantly delayed for new vaccines, as well as for hepatitis B (only 28% were vaccinated at 12 months of age), and 2nd dose of MMR (65% at 60 months of age). Child's increasing age as well as belonging to immigrant group were significantly associated with under- or delayed immunization status while use of multivalent vaccines had a positive impact on complete and age-appropriate immunization with most vaccines.Conclusions:Our results highlight the need to monitor uptake of new vaccines and reinforce appropriate administration of booster doses and hepatitis B vaccine. Immigration was identified as risk factor for suboptimal immunization with older vaccines, but with compliance in a controlled environment