Streptococcus mutans and Dental Caries in Native American Children

描述（由申请人提供）：龋齿是儿童期最普遍的慢性疾病。幼儿龋齿（ECC）是一种特别严重的龋齿形式，影响6岁以下的婴儿、幼儿和学龄前儿童。在美国普通人群中，2-5岁儿童的ECC患病率为2- 5%（NHANES III）。最近，1999-2002年的NHANES数据发现，幼儿龋齿的患病率从1988-94年期间增加，2- 5岁儿童的龋齿患病率从24%增加到28%（Beltran-Aguilar等人，2005）。与以前的调查一样，1999-2002年全国健康和营养状况调查数据显示，龋齿患病率和严重程度因种族/民族和贫困状况而存在巨大差异。然而，在美洲印第安人和阿拉斯加原住民（AI/AN）儿童中，疾病负担要高得多，79%的2-5岁AI/AN儿童患有ECC（IHS，2001年）。这种差异的原因尚不清楚，部分原因是尚未对这一高危人群中ECC的病因进行全面研究。在充分了解该病的病因之前，制定有效的预防战略的希望不大。本研究的总体目标是确定AI/AN婴幼儿ECC的风险因素，并确定变形链球菌（SM）单独或与环境和行为因素结合是否会增加美国土著儿童的龋齿风险。具体目标是：1）确定变形链球菌在美洲土著儿童中传播的时间性和保真度，2）表征变形链球菌特异性克隆的毒力决定子的表达，3）确定美洲土著受试者的牙菌斑样品中总可培养植物群、总变形链球菌和总酸性植物群随时间的组成，4）确定36个月内美国土著儿童ECC的发病率，5）确定美国土著婴儿和幼儿获得有毒SM克隆和ECC的饮食和营养风险因素。我们将与阿伯丁地区部落主席卫生委员会密切合作，与南达科他州松岭的奥格拉拉苏族部落社区合作，在分娩后1个月内招募200名土著母亲/儿童。有关潜在风险因素和龋齿状况的信息将每4个月收集一次，直到孩子36个月。作为我们培训AI/AN研究人员的努力的一部分，我们将聘请当地的项目协调员和牙科医生。我们相信，这种评估特定SM克隆的垂直传播，使用DNA指纹图谱的方法将提供有价值的信息，这些致龋细菌在这些美洲土著儿童的收购。

DESCRIPTION (provided by applicant): Dental caries is the single most prevalent chronic disease of childhood. Early childhood caries (ECC), a particularly severe form of caries, affects infants, toddlers and preschool children younger than 6 years. Among the general U.S. population, the prevalence of ECC is 25% among children 2-5 years (NHANES III). More recently, NHANES data from 1999-2002 found that the prevalence of caries in young children had increased from the 1988-94 time period, from 24% to 28% in 2- to 5-year-old children (Beltran-Aguilar, et al, 2005). As in the previous surveys, the 1999-2002 NHANES data revealed demonstrated profound disparities in Dental caries prevalence and severity based on race/ethnicity and poverty status. Among American Indian and Alaska Native (AI/AN) children, however, the disease burden is much higher, with 79% of 2-5 year old AI/AN children having ECC (IHS, 2001). The reason for this disparity is not understood, partially because a comprehensive study on the etiology of ECC in this high-risk population has not been undertaken. Until the etiology of the disease is fully understood, there is little hope of developing effective preventive strategies. The overall goal of this study is to identify risk factors for ECC among AI/AN infants and toddlers and to determine if Streptococcus mutans (SM) alone, or in combination with environmental and behavioral factors, increases risk of caries in Native American children. The Specific Aims are: 1) To determine the temporality and fidelity of transmission of Streptococcus mutans in Native American children, 2) To characterize expression of virulence determinants of specific clones of Streptococcus mutans, 3) To determine the composition of total cultivable flora, total Streptococcus mutans and total acid flora in plaque samples of Native American subjects over time, 4) To determine the incidence of ECC in Native American children through age 36 months, and 5) To identify dietary and nutritional risk factors for acquisition of virulent SM clones and ECC in Native American infants and toddlers. Working closely with the Health Board of the Aberdeen Area Tribal Chairman, we will work with the Oglala Sioux tribal community at Pine Ridge, South Dakota from which we will recruit 200 Native mother/child dyads within 1 month of delivery. Information on potential risk factors and caries status will be collected every 4 months until the child is 36 months. As part of our effort to train AI/AN researchers, we will hire a local program coordinator and Dental hygienists. We believe that this assessment of vertical transmission of specific SM clones using DNA fingerprinting approaches will provide valuable information on the acquisition of these cariogenic bacteria in these Native American children.