Costa Francine S, Silva Larissa A N, Cata-Preta Bianca O, Santos Thiago M, Ferreira Leonardo Z, Mengistu Tewodaj, Hogan Daniel R, Barros Aluisio J D, Victora Cesar G
International Center for Equity in Health, Federal University of Pelotas, Pelotas, Brazil.
Postgraduate Program in Epidemiology, Federal University of Pelotas, Pelotas, Brazil.
EClinicalMedicine. 2024 Mar 16;71:102547. doi: 10.1016/j.eclinm.2024.102547. eCollection 2024 May.
Identification of unvaccinated children is important for preventing deaths due to infections. Number of siblings and birth order have been postulated as risk factors for zero-dose prevalence.
We analysed nationally representative cross-sectional surveys from 85 low and middle-income countries (2010-2020) with information on immunisation status of children aged 12-35 months. Zero-dose prevalence was defined as the failure to receive any doses of DPT (diphtheria-pertussis-tetanus) vaccine. We examined associations with birth order and the number of siblings, adjusting for child's sex, maternal age and education, household wealth quintiles and place of residence. Poisson regression was used to calculate zero-dose prevalence ratios.
We studied 375,548 children, of whom 13.7% (n = 51,450) were classified as zero-dose. Prevalence increased monotonically with birth order and with the number of siblings, with prevalence increasing from 11.0% for firstborn children to 17.1% for birth order 5 or higher, and from 10.5% for children with no siblings to 17.2% for those with four or more siblings. Adjustment for confounders attenuated but did not eliminate these associations. The number of siblings remained as a strong risk factor when adjusted for confounders and birth order, but the reverse was not observed. Among children with the same number of siblings, there was no clear pattern in zero-dose prevalence by birth order; for instance, among children with two siblings, the prevalence was 13.0%, 14.7%, and 13.3% for firstborn, second, and third-born, respectively. Similar results were observed for girls and boys. 9513 families had two children aged 12-35 months. When the younger sibling was unvaccinated, 61.9% of the older siblings were also unvaccinated. On the other hand, when the younger sibling was vaccinated, only 5.9% of the older siblings were unvaccinated.
The number of siblings is a better predictor than birth order in identifying children to be targeted by immunization campaigns. Zero-dose children tend to be clustered within families.
Gavi, the Vaccine Alliance.
识别未接种疫苗的儿童对于预防感染导致的死亡至关重要。兄弟姐妹数量和出生顺序被假定为零剂次疫苗接种率的风险因素。
我们分析了来自85个低收入和中等收入国家（2010 - 2020年）具有全国代表性的横断面调查数据，这些数据包含12至35个月龄儿童的免疫接种状况信息。零剂次疫苗接种率定义为未接种任何剂量白喉 - 百日咳 - 破伤风（DPT）疫苗。我们研究了出生顺序和兄弟姐妹数量与零剂次疫苗接种率的关联，并对儿童性别、母亲年龄和教育程度、家庭财富五分位数以及居住地点进行了调整。采用泊松回归计算零剂次疫苗接种率比。
我们研究了375,548名儿童，其中13.7%（n = 51,450）被归类为零剂次接种。疫苗接种率随出生顺序和兄弟姐妹数量的增加而单调上升，头胎儿童的接种率为11.0%，出生顺序为5或更高的儿童接种率为17.1%；无兄弟姐妹的儿童接种率为10.5%，有四个或更多兄弟姐妹的儿童接种率为17.2%。对混杂因素进行调整后，这些关联有所减弱，但并未消除。在对混杂因素和出生顺序进行调整后，兄弟姐妹数量仍然是一个强烈的风险因素，但反之则未观察到。在兄弟姐妹数量相同的儿童中，按出生顺序划分的零剂次疫苗接种率没有明显模式；例如，在有两个兄弟姐妹的儿童中，头胎、二胎和三胎的接种率分别为13.0%、14.7%和13.3%。男孩和女孩的结果相似。9513个家庭有两个12至35个月龄的孩子。当弟弟妹妹未接种疫苗时，61.9%的哥哥姐姐也未接种。另一方面，当弟弟妹妹接种疫苗时，只有5.9%的哥哥姐姐未接种。
在确定免疫接种运动的目标儿童方面，兄弟姐妹数量比出生顺序是更好的预测指标。零剂次接种儿童往往在家庭中聚集。
疫苗免疫全球联盟（Gavi）。
