Streptococcal pharyngitis in slum versus non-slum communities in Salvador Brazil

描述（由申请方提供）：链球菌性咽炎是风湿性心脏病（RHD）慢性疾病过程之前的急性疾病。最近的研究表明，热带环境中RHD的微生物学和流行病学特征与文献中描述的不同，这些文献主要基于温带社区的研究。这些差异是由于温带环境还是热带环境，还是由于所谓的热带地区贫民窟和非贫民窟的社区结构的性质，仍然不得而知。在巴西，风湿性心脏病似乎主要发生在居住在城市贫民窟的人群中。贫民窟的风湿性心脏病流行病学可能与文献中描述的非常不同。这可能是由于贫民窟的结构、社会或其他方面的原因。有效的预防策略取决于对人群中疾病动态的了解。因此，本项目旨在研究已知与这些社区RHD最终结果相关的早期事件。具体而言，该项目将比较同一城市中心贫民窟与非贫民窟的对比人群中链球菌性咽炎的流行病学和微生物学。具体目标：疾病预防控制中心健康世界中健康人的健康保护目标之一是预防传染病及其后果。本研究将通过以下研究帮助实现这一目标：1。对来自发展中国家（萨尔瓦多，巴西）相同城市环境中贫民窟和非贫民窟人群的咽炎（症状性）病例的A组链球菌分离株的多样性和克隆组成进行评估，并将这些分离株与来自发达国家（奥克兰，加利福尼亚州，美国）不相关地理环境的GAS人群结构进行比较;以及2.）在三个人群中对G群链球菌（GGS）和C群链球菌（GCS）在咽炎（症状性）病例中的相对患病率、比例和克隆组成进行评价：巴西萨尔瓦多的贫民窟和非贫民窟人群;以及美国加利福尼亚州奥克兰的儿科人群。研究设计和方法：将从巴西萨尔瓦多的两个诊所的5-14岁咽炎儿童中收集链球菌分离株。一个诊所为社会经济地位高的人口服务，另一个诊所为贫民窟人口服务。将对分离株进行基因分型，并采用emm分型和多位点序列分型（MLST）分析克隆多样性和血清组。结论：通过解决这些目标，这项研究将确定是否链球菌性咽炎在贫民窟人口的模式不同于医学文献中所描述的，也从同一个城市的社区，但不被视为贫民窟。过去的文献表明，菌株类型（基于M表面蛋白）对RHD的发展具有重要意义。我们在RHD高风险的贫民窟社区评估这一已知的风险因素是很重要的。

DESCRIPTION (provided by applicant): Streptococcal pharyngitis is the acute disease that precedes the chronic disease process of rheumatic heart disease (RHD). Recent studies have revealed that the microbiologic and epidemiologic features of RHD in tropical environments are distinct from those described in the literature, which are based mostly on studies from temperate zone communities. Whether these differences are due to temperate versus tropical environment, or the nature of community structures in the so-called tropical areas slum versus non- slum remains unknown. In Brazil, RHD appears to occur predominantly in populations that reside in urban slums (favelas). RHD epidemiology in slums may be very distinct from what is described in the literature. This may be due to structural, social or other aspects of slums. Effective prevention strategies depend on understanding the disease dynamics in a population. Therefore, this project seeks to study the early events that are known to be associated with the eventual outcome of RHD in these communities. Specifically, this project will compare the epidemiology and microbiology of streptococcal pharyngitis in contrasting populations- -slum versus non-slum--in the same urban center. Specific Aims: One aim of the CDC Health Protection Goal of Healthy People in a Healthy World is to prevent infectious diseases and their consequences. This study will help achieve this objective with the following studies: 1.) An assessment of the diversity and clonal composition of Group A Streptococcus isolates from pharyngitis (symptomatic) cases from favela and non-favela populations in the same urban setting in a developing country (Salvador, Brazil), and a comparison of these isolates with the population structure of GAS from an unrelated geographic setting in a developed country (Oakland, CA, USA); and 2.) An evaluation of the relative prevalence, proportion, and clonal composition of Group G Streptococcus (GGS) and Group C Streptococcus (GCS) from pharyngitis (symptomatic) cases in three populations: favela and non-favela populations in Salvador, Brazil; and a pediatric population in Oakland, CA, USA. Research Design and Methods: Streptococcal isolates will be collected from children aged 5-14 who present with pharyngitis to two clinics in Salvador, Brazil. One clinic serves a population with high socioeconomic status, and the other clinic serves a favela population. Isolates will be genotyped and analyzed for clonal diversity and serogroup with emm-typing, as well as multilocus sequence typing (MLST). Conclusion: By addressing these aims, this study will determine whether streptococcal pharyngitis in a slum population has patterns distinct from that described in the medical literature; and also from communities in the same city but which are not considered slums. Past literature has demonstrated that strain type (based on M surface protein) has important implications for development of RHD. It is important that we assess this known risk factor in a slum community at high risk for RHD.