Assessing the factors affecting routine childhood immunization among caregivers of children under five years in Southwestern Nigeria: a cross-sectional study

Childhood immunization coverage remains a significant public health challenge, particularly in low- and middle-income countries. This study assessed caregivers’ knowledge, perceptions, and the factors influencing the immunization status of children under five years of age following the STROBE guidelines. We conducted a facility-based cross-sectional study among caregivers of children under five years old from August to October 2024. We selected 522 caregivers through convenience sampling from five primary health centers in Ogun State. Data were collected using a semi-structured, interviewer-administered, validated (Cronbach’s alpha, 0.911) questionnaire. We performed descriptive statistics, Chi-square tests, and binomial logistic regression using R software, with statistical significance set at p < 0.05. Among the 522 caregivers surveyed, 96.4% were female, with a mean (SD) age of 29.86 ± 5.93 years. Most were married (95.6%) and had one or two children under five. Additionally, 89.9% of caregivers demonstrated good knowledge, and 96% held positive perceptions of immunization. Caregivers aged 35 to 44 years were twice as likely to have a positive perception of childhood immunization (OR = 2.156, 95% CI [1.19, 3.89], p = 0.011) compared to those aged 17 to 24. Compared to unemployed caregivers, those formally employed were six times more likely to have a positive perception (OR = 6.316, 95% CI [2.16–18.41], p = 0.001). Caregivers with positive perceptions of immunization were twice as likely to have their children immunized (OR = 2.07, 95% CI (1.21–3.52), p = 0.007) compared with those with negative perceptions. Factors influencing immunization uptake included long distances (75%), vaccine unavailability (60.3%), financial constraints (57.7%), and religious beliefs (52%). Healthcare providers were the primary source of information. The study revealed that caregivers have adequate knowledge and positive perceptions of childhood immunization. Age and employment were significantly associated with caregivers’ perceptions. Caregivers with positive perceptions are likely to have their children immunized. The study highlighted various factors affecting childhood immunization, including service delivery barriers such as vaccine unavailability, cultural beliefs, and practices. Hence, culturally specific educational interventions are needed to correct vaccine misconceptions. Government subsidies for immunization services and products could enhance access and increase immunization rates.