The Prevalence of Complete, Timely and Delayed Primary Childhood Vaccination in Malaysia: Insights from the 2022 National Maternal and Child Health Survey

An effective primary childhood vaccination programme ensures high vaccine coverage, with vaccinations administered within the recommended timeframe. However, there is a lack of information on the timeliness of these vaccinations. This study aimed to assess the completeness and timeliness of primary childhood vaccinations in Malaysia. Data from a nationwide cross-sectional survey were analysed. Complete vaccination refers to children who received all primary vaccines regardless of the recommended timeframe. Timely vaccination is defined as vaccines administered within the recommended timeframe, while delayed vaccination refers to those given after this period. Immunisation records were verified by trained nurses. A total of 3,523 children aged 12 to 23 months participated in this survey. The prevalence of overall vaccination coverage was 87.1% (95% CI: 84.9, 89.1). Within this cohort, the prevalence of timely vaccination was 51.2% (95% CI: 47.2, 55.2), while the prevalence of delayed vaccination was 35.6% (95% CI: 31.7, 39.7). The prevalence of delayed vaccination particularly evident in the second dose of pneumococcal and measles-mumps-rubella vaccines at 15.0% (95% CI: 12.8, 17.5) and 11.2% (95% CI: 8.1, 15.3), respectively. Urban-rural disparities were evident, with urban areas demonstrating higher delayed vaccination prevalence (39.0%) than rural areas (27.6%). Johor, Selangor, and Kuala Lumpur & Putrajaya had the highest overall delayed vaccination prevalence (45.5%, 43.0%, and 42.5%, respectively). Malaysia demonstrates commendable overall vaccination coverage at 87.1%; however, the timeliness of vaccination remains a concern, with only 51.2% of children receiving vaccinations within the recommended timeframe. Significant disparities exist between urban and rural areas as well as among states in delayed vaccination rates, likely attributed to the presence of urban poor populations who are less exposed to the importance of vaccination and higher levels of vaccine hesitancy among urban parents. This highlights the need for public health interventions to focus on children in urban areas to improve timely vaccination rates and maximise the effectiveness of immunisation programs.