Associated Factors to Immunization Timeliness and Completion in Preterm and Low Birth Weight Infants at Essos Hospital Center Yaounde

Introduction: Vaccination is very often delayed in premature and low birth weight infants. However, timely vaccination is even more important in this population because of their increased susceptibility to infection. Objective: To assess immunization practice and factors associated with vaccine promptness and completeness in former preterm and low-birth-weight infants. Methods: We conducted a retrospective analytical cross-sectional study (January 2017 to February 2019). Main Measurement: Promptness and completeness at each contact, Statistical analysis was performed using R software version 3.6.2, logistic regression was used to estimate the Odds Ratio (OR) and their 95% Confidence Interval (CI). Results: We recruited 310 children aged 12 to 36 months born before 37 weeks with low birth weight, 163 (52.6%) of whom were female. Two hundred and fifty-three had received the vaccines at the indicated age, with promptness rate of 81.6%, and 97.7% had completed routine immunization at 9 months. The mean age at vaccination initiation was 6 days ± 11 and the mean weight at vaccination initiation was 2233 g ± 494. High prematurity and very low birth weight were associated with a high rate of vaccine delay: 61.5% [OR: 15.56;(CI: 3.22 - 118.52;p = 0.002)] and 66.7% [OR: 19.19;(CI: 4.67 - 92.52;p < 0.001)] respectively. Distance > 5 km with EHC [OR: 3.48;(CI: 1.68 - 7.47;p = 0.001)] was associated with poor vaccination. Women in common-law unions had the lowest vaccine readiness rate (60.6%), (OR: 3.36;CI: 1.006 - 10.70;p = 0.038). The frequency of occurrence of post immunization adverse events was 24.5%, with fever type in 94.7%. Conclusion: Almost all premature and/or low-birth-weight children hospitalized at Essos Hospital Center had completed routine immunization at 9 months, and the majority had received the vaccines in a timely manner. Similar study is needed in rural area.