Dows Institute for Dental Research, University of Iowa, College of Dentistry, Iowa City, IA, USA.
Preventive and Community Dentistry, University of Iowa, College of Dentistry, Iowa City, IA, USA.
J Oral Microbiol. 2015 Apr 1;7:27182. doi: 10.3402/jom.v7.27182. eCollection 2015.
Severe-early childhood caries (S-ECC) is one of the most common infectious diseases in children and is prevalent in lower socio-economic populations. American Indian children suffer from the highest levels of S-ECC in the United States. Members of the mutans streptococci, Streptococcus mutans, in particular, are key etiologic agents in the development of caries. Children typically acquire S. mutans from their mothers and early acquisition is often associated with higher levels of tooth decay.
We have conducted a 5-year birth cohort study with a Northern Plains Tribe to determine the temporality and fidelity of S. mutans transmission from mother to child in addition to the genotypic diversity of S. mutans in this community. Plaque samples were collected from 239 mother/child dyads at regular intervals from birth to 36 months and S. mutans were isolated and genotyped by arbitrarily primed-polymerase chain reaction (AP-PCR).
Here we present preliminary findings from a subset of the cohort. The focus for this paper is on initial acquisition events in the children. We identified 17 unique genotypes in 711 S. mutans isolates in our subset of 40 children, 40 mothers and 14 primary caregivers. Twelve of these genotypes were identified in more than one individual. S. mutans colonization occurred by 16 months in 57.5% of the children and early colonization was associated with higher decayed, missing and filled surface (DMFS) scores (p=0.0007). Children colonized by S. mutans shared a common genotype with their mothers 47.8% of the time. While multiple genotypes were common in adults, only 10% of children harbored multiple genotypes.
These children acquire S. mutans at an earlier age than the originally described 'window of infectivity' and often, but not exclusively, from their mothers. Early acquisition is associated with both the caries status of the children and the mothers.
严重婴幼儿龋（S-ECC）是儿童中最常见的传染病之一，在社会经济地位较低的人群中较为普遍。美国印第安儿童患有 S-ECC 的比例位居全美最高。变形链球菌是变异链球菌的一种，是导致龋齿的主要病因。儿童通常从母亲那里获得 S. mutans，早期获得通常与更高的龋齿水平有关。
我们对一个北平原部落进行了为期 5 年的出生队列研究，以确定 S. mutans 从母亲到孩子的传播的时间顺序和保真度，以及该社区中 S. mutans 的基因型多样性。在出生至 36 个月的定期间隔内，从 239 对母婴对中采集牙菌斑样本，并通过任意引物聚合酶链反应（AP-PCR）分离和分型 S. mutans。
本研究报告了该队列的初步研究结果。本文的重点是儿童的初始获得事件。我们在我们的 40 名儿童、40 名母亲和 14 名主要照顾者的子集中的 711 株 S. mutans 分离株中鉴定出 17 种独特的基因型，其中 12 种基因型在一个以上个体中被鉴定出来。57.5%的儿童在 16 个月时发生 S. mutans 定植，早期定植与更高的龋失补牙面（DMFS）评分相关（p=0.0007）。47.8%的时间，被 S. mutans 定植的儿童与他们的母亲共享相同的基因型。虽然成年人中多种基因型很常见，但只有 10%的儿童携带多种基因型。
这些儿童获得 S. mutans 的年龄比最初描述的“感染窗口期”更早，而且通常但并非总是从母亲那里获得。早期获得与儿童和母亲的龋齿状况有关。
