Adherence to pneumococcal conjugate vaccination schedule and uptake rate as compared to the established diphtheria-tetanus-acellular pertussis vaccination in Cyprus

Abstract

Background: Pneumococcus is a common cause of invasive and non-invasive infections in children. In areas with high vaccination coverage, universal infant vaccination with conjugated pneumococcal vaccine (PCV) has significantly decreased the incidence of vaccine type nasopharyngeal carriage and invasive pneumococcal disease. The aim of this study is to examine immunization coverage rate and timely administration of the recently introduced PCV and compare to the established diphtheria-tetanus-acellular pertussis vaccine (DTaP) with similar schedule.

Methods: A stratified random sample of healthy infants and children 6-36 months of age were recruited. Demographic data were collected from parents. Among enrolled children, immunization status for DTaP and PCV was noted from the child's health booklet.

Results: Of 1105 children enrolled in the study, 586 (53%) were vaccinated in the private sector and the rest in the public sector. A significant higher proportion of children vaccinated at the private sector were fully vaccinated for PCV (71% versus 58%, p < 0.05) while no difference in the DTaP coverage was observed. Conversely, the compliance to the recommended vaccination schedule was much higher in the public sector for the first and second dose of PCV and second dose of DTaP. The overall, timely administration was higher for the DTaP vaccine when compared to PCV (p < 0.05). Moreover, adherence to the program was higher for the firstborn child of the family while significant differences were observed between different geographic regions. Interestingly, co-administration of DTaP and PCV was observed in only 2% of the children.

Conclusion: In children residing in Cyprus, vaccination coverage and adherence to PCV vaccination schedule are significantly lower compared to the established DTaP vaccine. There is an urgent need for increasing the overall vaccination coverage as well as improving the adherence to vaccination schedule. Possible interventions are proposed.

Keywords: Adherence; Immunization coverage; Pneumococcal conjugate vaccine; Timely administration.