Streptococcus mutans and Dental Caries in Native American Children

描述(申请人提供)：龋齿是最常见的儿童慢性病。幼儿龋病(ECC)是一种特别严重的龋病，影响婴幼儿和6岁以下的学龄前儿童。在美国普通人群中，2-5岁儿童中ECC的患病率为25%(NHANES III)。最近，NHANES 1999-2002年的数据发现，幼儿的龋齿患病率从1988-94年间的24%上升到2-5岁儿童的28%(Beltran-Aguar等人，2005年)。与前几次调查一样，1999-2002年的NHANES数据显示，根据种族/族裔和贫困状况，龋齿患病率和严重程度存在严重差异。然而，在美洲印第安人和阿拉斯加土著(AI/AN)儿童中，疾病负担要高得多，2-5岁的AI/AN儿童中有79%患有ECC(IHS，2001)。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的ECC病因学进行全面研究。在完全了解这种疾病的病因之前，制定有效的预防策略的希望微乎其微。这项研究的总体目标是确定AI/AN婴儿和蹒跚学步的儿童患ECC的危险因素，并确定变形链球菌(SM)是否单独或与环境和行为因素一起增加美洲原住民儿童的龋病风险。其具体目标是：1)确定变形链球菌在美洲原住民儿童中传播的暂时性和保真性，2)确定变形链球菌特定克隆的毒力决定因素的表达，3)确定美洲原住民受试者菌斑样本中总可培养菌群、总变形链球菌和总酸性菌群随时间的变化，4)确定36个月龄美洲原住民儿童ECC的发生率，以及5)确定饮食和营养危险因素，以获得毒力SM克隆和美洲原住民婴幼儿的ECC。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Pine Ridge的Oglala Sioux部落社区合作，在分娩后1个月内从那里招募200名土著母婴。关于潜在危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个月大。作为我们培训AI/AN研究人员的努力的一部分，我们将聘请一名当地项目协调员和牙科卫生员。我们相信，使用DNA指纹方法对特定SM克隆垂直传播的评估将为这些美洲原住民儿童获得这些致龋菌提供有价值的信息。

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.