Vaccination Status in Children with Chronic Diseases: Are They Up-to-Date for Mandatory and Specific Vaccines?

The aim of this study is to investigate the immunization coverage for mandatory and specific vaccines in a group of children with chronic diseases.

Children with chronic diseases aged 6 months to 18 years who were followed up by outpatient subspecialty clinics of a tertiary hospital were enrolled. Children who were up-to-date and who were under-vaccinated were compared with respect to demographic characteristics, parental educational status, healthcare providers' attitudes toward vaccination, age at the time of diagnosis, and duration of follow-up.

A total of 366 patients with variable chronic diseases were enrolled. Of these, 84.7% were up-to-date for the mandatory vaccines. This rate was 99.5% for the primary series of diphtheria-tetanus-acellular pertussis and 98.9% for the first dose of measles-mumps-rubella vaccines. Vaccination coverage for specific vaccines was low (13.9% for influenza and 55% for conjugated pneumococcal vaccine). Being older at the time of diagnosis increased the likelihood of being up-to-date for mandatory vaccines by 1.1 times, while being followed up from multiple subspecialty outpatient clinics and attendance to private doctors' clinics for vaccination increased the likelihood of being up-to-date for specific vaccines by 19.1 and 6.4 times, respectively.

In this study, immunization coverage for mandatory vaccines was comparable to that of the general population. However, vaccination coverage was low for specific vaccines. Therefore, efforts of prioritization of pediatric immunizations and raising awareness among healthcare providers about the impact of medical recommendations for specific vaccines among children with chronic diseases can help to improve vaccination rates.