Timeliness and factors associated with childhood vaccinations among children aged 12 to 24 months in Hoima District, Uganda

Abstract

Introduction: Timely vaccination is important to ensure adequate immune response and protect children from common infectious diseases. In Uganda, less than half of children receive all vaccines within the recommended time ranges. Factors responsible for a child not getting vaccinated have been extensively studied in both developed and developing countries, but limited knowledge still exists about factors determining timely vaccinations. The aim of this study was to examine the timeliness of childhood vaccinations and to identify factors associated with receiving vaccines in timely manner among children aged 12 to 24 months in Hoima District, Uganda. Methods: This was a community-based cross-sectional study conducted among 660 eligible households with children aged 12 to 24 months in four divisions of Hoima Municipality. A two stage sampling technique was used for the selection of study participants using sampling proportionate to infant population size. The WHO 2005 cluster sampling methodology was used to identify households for inclusion in the study. One child was interviewed per household. Timeliness of vaccinations were assessed with Kaplan-Meier time-to-event analysis for each vaccine based on the following time ranges: BCG (Birth to 8 weeks), Polio 0 (Birth to 4 weeks), Polio 1 (4 weeks to 2 months), Polio 2 (8 weeks to 4 months), Polio 3 (12 weeks to 6 months), Penta-Heb-Hib 1 (4 weeks to 2 months). Penta-Heb-Hib 2 (8 weeks to 4 months), Penta-Heb-Hib 3 (12 weeks to 6 months) and measles vaccines (38 weeks to 12 months). Cox regression analysis was used to identify factors associated with timeliness of vaccination. Results: Overall, less than half of children in Hoima received all vaccines within the recommended time ranges (43.4%; 95% CI 39.4-47.4). Timely receipt of vaccines was lowest for measles (58.2%; 95%CI 54.2-62.2) and highest (93.4%; 95% CI 91.4-95.5) for BCG vaccine. Timely receipt of vaccinations was 2 times higher if the caretakers reported that they remembered immunization appointments (AHR 2.08; 95% CI 1.02-4.25), 1.4 times higher if the caretakers received vaccination services within 30 minutes from arrival (AHR 1.44; 95% CI 0.100-2.07) and the mother’s age group between 20-24 years (AHR 0.29; 95% CI 0.13-0.67) and 25+ years (AHR 0.31; 95% CI 0.14-0.71) were associated with decreasing timely vaccination compare to those less than 20 years. About 62% of the study respondents reported that long waiting times or queues would stop them from seeking immunization services. Conclusion: The prevalence of children who receive all vaccines within the recommended times ranges is still low in this study setting. Health education of caretakers on the importance of remembering immunization dates for the next vaccination dose is necessary to improve the proportion of those children who receive vaccinations in time. The long waiting times or queues in health facilities could arise from health worker being absent or reported work later time and having few health workers in facilities. Thus Hoima health authority should implements strategies to improve waiting time for vaccination services.