Determination of factors affecting the vaccination status of children aged 12-35 months in Lao People's Democratic Republic.

Vaccines are one of the most important achievements in public health, and a major contributor to this success is the Expanded Programme on Immunization. The utilisation of vaccination services and completion of the recommended schedule are determined by numerous factors. In Lao People's Democratic Republic (Lao PDR), the overall immunisation coverage has been improving. However, notwithstanding the improvement in immunisation coverage and the supplementary immunisation activities, there have been measles, diphtheria, and polio outbreaks in the country. The recent multicounty study of household health surveys revealed that the within-country economic-related inequality in the delivery of a vaccine was still high in Lao PDR. Our previous work evaluated the factors associated with vaccination status among the children aged 5-9 years old, which was older age group for this type of study. This study evaluated factors that affect vaccination status among children aged between 12 and 35 months. It is a nationwide population-based cross-sectional study that used data obtained through multistage cluster sampling. We found that the proportion of infants who were fully immunised was lower than the national target and that "maternal ethnicity" (odds ratio (OR) 0.34, 95% confidence interval [CI]: 0.20-0.60), "paternal education" (OR 1.87, 95% CI: 1.12-3.10), and "source of information about vaccination date by medical staff" (OR 1.65, 95% CI: 1.01-2.71) were significantly associated with the children's vaccination status. Numerous factors are associated with the completion of the recommended vaccine schedule, and some factors are location-specific. Identification of these factors should lead to actions for facilitating the optimal use of vaccination services by all the children in Lao PDR.