Rauniyar Santosh Kumar, Munkhbat Enkhtuya, Ueda Peter, Yoneoka Daisuke, Shibuya Kenji, Nomura Shuhei
Department of Global Health Policy, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Clinical Epidemiology Division, Department of Medicine, Solna, Karolinska Institute, Stockholm, Sweden.
Heliyon. 2020 Sep 18;6(9):e04898. doi: 10.1016/j.heliyon.2020.e04898. eCollection 2020 Sep.
Routine vaccination at the recommended age is crucial to minimize the risk of acquiring vaccine preventable diseases. This study aimed to assess the proportion of children receiving routine immunization at the recommended age and determinants of timely (age-appropriate) vaccination in Mongolia.
A total of 879 eligible children aged 12-23 months were included in this study. We investigated age-appropriate administration of Bacillus Calmette-Guerin vaccine (BCG); hepatitis B vaccine (Hep B); oral polio vaccine (OPV); pentavalent vaccine; and measles, mumps, and rubella vaccine (MMR) using Kaplan-Meier method. Multilevel logistic regression with random intercept at cluster level was used to assess the determinants of age-appropriate vaccination.
Overall, the crude vaccination coverage for routine vaccinations were above 90% for all vaccines except MMR1 which was 86.0% (95% CI, 83.6-88.2). While the first dose of almost all the vaccines given at birth; BCG, Hep B, and OPV0, were administered in a timely manner, a substantial proportion of second and third doses of these vaccines were not given in a timely manner with age-appropriate vaccination coverage ranging from 35.9% (32.8-39.1%) for MMR1 to 67.7% (64.5-70.7%) for OPV1 respectively. Factors associated with age-appropriate administration of the investigated vaccines included socio-economic status of household, religion of household heads, area of residence, owning mobile phone, and season of childbirth. For instance, children belonging to households from richer wealth quintile had higher possibilities of getting age-appropriate OPV1-OPV3, PE1-PE3 and MMR1 vaccines compared to those from the poorest household wealth quintile.
Our findings suggest that the commonly used indicator 'crude vaccination coverage' could be supplemented by 'age-appropriate vaccination' to help to identify gaps in timely vaccinations and stimulate interventions in Mongolia. Factors such as household wealth quintile, place of residence and religion associated with timely vaccination in our study could be considered to promote effective intervention aiming to improve adequate vaccination coverage.
在推荐年龄进行常规疫苗接种对于将感染疫苗可预防疾病的风险降至最低至关重要。本研究旨在评估蒙古按推荐年龄接受常规免疫接种的儿童比例以及及时（适龄）接种疫苗的决定因素。
本研究共纳入879名年龄在12至23个月的符合条件的儿童。我们使用Kaplan-Meier方法调查卡介苗（BCG）、乙肝疫苗（Hep B）、口服脊髓灰质炎疫苗（OPV）、五价疫苗以及麻疹、腮腺炎和风疹疫苗（MMR）的适龄接种情况。采用在聚类水平具有随机截距的多水平逻辑回归来评估适龄接种疫苗的决定因素。
总体而言，除第一剂麻疹、腮腺炎和风疹疫苗（MMR1）接种率为86.0%（95%置信区间，83.6 - 88.2）外，所有疫苗的常规接种粗覆盖率均高于90%。虽然几乎所有在出生时接种的第一剂疫苗，即卡介苗、乙肝疫苗和OPV0，都能及时接种，但这些疫苗的第二剂和第三剂有很大一部分未及时接种，适龄接种覆盖率分别从MMR1的35.9%（32.8 - 39.1%）到OPV1的67.7%（64.5 - 70.7%）不等。与所调查疫苗的适龄接种相关的因素包括家庭社会经济地位、户主宗教信仰、居住地区、是否拥有手机以及分娩季节。例如，与最贫困家庭财富五分位数的儿童相比，来自较富裕财富五分位数家庭的儿童更有可能适龄接种OPV1 - OPV3、PE1 - PE3和MMR1疫苗。
我们的研究结果表明，常用指标“常规接种覆盖率”可以用“适龄接种率”来补充，以帮助识别及时接种疫苗方面的差距并推动蒙古的干预措施。在我们的研究中，与及时接种疫苗相关的家庭财富五分位数、居住地点和宗教信仰等因素可被考虑用于促进旨在提高充分接种覆盖率的有效干预措施。
