Investigation of Occupational Exposure to and Infection by MRSA in Rural Iowa

描述（由申请人提供）：我致力于将我在基础微生物学和传染病研究方面的经验和背景与我在职业和环境卫生方面的培训结合起来，以便更好地了解工作场所接触传染性病原体与这些接触相关疾病的后续发展和/或传播之间的复杂关系。虽然我到目前为止在这里的经历使我处于成为一名独立调查员的绝佳位置，但我仍然需要在职业和农业健康方面接受额外的培训（正式课程和指导），这将是这个奖项所能提供的。这将有助于我实现近期的职业目标（将时间集中在这份申请中提出的研究上，并参加职业与环境健康方面的额外课程，以扩大我在这些领域的背景），以及我的长期目标，即成为该领域的领导者，并最终成为一名全职教授。职业与环境健康系由来自不同学科的19名初级教师组成。这些多元化的教职员工每年带来1400万美元的校外资金。资金来自广泛的联邦和州机构，以及私人基金会。主要资助者包括国家伤害预防和控制中心、国家职业安全与健康研究所、国家环境健康科学研究所和环境保护局。该司和选定的导师是农村卫生，包括农业卫生和医学研究的领导者。研究计划最近的一份报告记录了耐甲氧西林金黄色葡萄球菌（MRSA）的临床影响，表明MRSA在2005年在美国造成了超过94,000例侵袭性感染和超过18,000例死亡，使HIV黯然失色，成为主要的传染病杀手。2005年，这些感染中的大多数与接触医疗保健有关；然而，这种趋势正在改变。社区相关的MRSA菌株USA300最近在31.5%的侵袭性MRSA分离株中被发现来自美国大都市地区。随着MRSA流行病学的变化，出现了新的MRSA感染风险群体。最初，与医疗机构接触的个人是MRSA携带和感染的主要风险群体；然而，在过去的十年中，运动员、注射吸毒者和囚犯也出现了MRSA感染的风险群体。来自欧洲和加拿大的报告报告了另一个潜在的耐甲氧西林金黄色葡萄球菌风险群体：与牲畜和家禽接触的个人。由于我们小组的初步研究已经记录了美国猪中MRSA的存在，我们寻求扩大这项研究，并在职业接触牲畜和家禽的个体中更广泛地检查金黄色葡萄球菌的流行病学。我们的主要目标是确定金黄色葡萄球菌（包括MRSA）在爱荷华州牲畜和家禽农场的流行情况，从动物、人类工人和环境中取样。在这项研究中，我们将检查30个农场，包括有活猪、牛和家禽的农场。在我们的研究计划的第二部分，我们将检查金黄色葡萄球菌的传播由殖民地农民到密切的家庭接触者，以确定有机体的运动到个人缺乏职业接触。最后，我们将与在牲畜高度集中地区工作的农村医生合作，以检查职业接触者中金黄色葡萄球菌引起的症状性感染。我们的主要假设是，在牲畜和家禽附近工作的个人将面临职业暴露于金黄色葡萄球菌的风险，并且这种有机体将传播给与工人密切接触的配偶和其他家庭成员。我们进一步假设，与牲畜（特别是猪）接触的农民可能会被“猪相关”菌株（如ST398）定植，这些菌株也会在我们的农村医生发现的有症状的感染中发现。这项研究的发现将使我们能够计划干预措施，以减少职业暴露于这种生物体，并在未来的研究中实施这些干预措施。

DESCRIPTION (provided by applicant): I am committed to integrating my experience and background in basic microbiology and infectious disease research with my training in occupational and environmental health so as to better understand the complex relationships between exposure to infectious agents in the workplace and the subsequent development and/or spread of disease related to these exposures. While my experience here to date has put me in an excellent position to become an independent investigator, I still need additional training (formal coursework and mentoring) in occupational and agricultural health, which this Award would provide. This would assist me in meeting my immediate career goals (focusing time on the research proposed in this application, and taking additional coursework in Occupational and Environmental Health in order to broaden my background in these areas), as well as my long-term goals of gaining recognition as a leader in this field, and eventually becoming a full Professor with tenure. Environment The Department of Occupational and Environmental Health is comprised of 19 primary faculty from a wide variety of disciplines. This diverse group of faculty members brings in $14 million in extramural funding each year. Funding comes from a wide range of federal and state agencies, as well as from private foundations. Lead funders include the National Center for Injury Prevention and Control, National Institute for Occupational Safety and Health, the National Institute of Environmental Health Sciences, and the Environmental Protection Agency. The Department and selected mentors are leaders in the study of rural health, including agricultural health and medicine. Research Plan A recent report has documented the clinical impact of methicillin-resistant Staphylococcus aureus (MRSA), suggesting that MRSA caused over 94,000 invasive infections and more than 18,000 deaths in the United States in 2005, eclipsing HIV as a leading infectious disease killer. In 2005, the majority of these infections were associated with healthcare exposure; however, this trend is changing. Community-associated MRSA strain USA300 was recently found in 31.5% of invasive MRSA isolates collected from US metropolitan areas. As the epidemiology of MRSA has changed, new groups at risk of acquiring MRSA have emerged. Initially individuals with health care contact were the main risk group for MRSA carriage and infection; however, in the past decade, athletes, injection drug users, and prisoners have also emerged as groups at risk of MRSA infection. Reports from Europe and Canada have reported another potential MRSA risk group: individuals in contact with livestock and poultry. As pilot studies by our group have documented the presence of MRSA in US swine, we seek to expand upon this research and examine the epidemiology of Staphylococcus aureus more broadly in individuals with occupational exposure to livestock and poultry. Our primary objectives are to determine the prevalence of S. aureus (including MRSA) on Iowa livestock and poultry farms, sampling from animals, human workers, and the environment. We will examine 30 farms during this research, including farms with live swine, cattle, and poultry. In the second part of our research plan, we will examine transmission of S. aureus by colonized farmers to close family contacts, in order to determine movement of organisms to individuals lacking occupational exposure. Finally, we will partner with rural physicians working in areas of high livestock concentration, in order to examine symptomatic infections caused by S. aureus in individuals with occupational exposure. Our central hypothesis is that individuals working in close proximity to livestock and poultry will be at risk of occupational exposure to S. aureus, and that this organism will be transmitted to spouses and other family members in close contact to the worker. We further hypothesize that farmers in contact with livestock (and swine in particular) will be likely to be colonized with "swine-associated" strains (such as ST398), and that these strains will also be found in symptomatic infections identified by our rural physicians. Findings from this research will allow us to plan interventions to reduce occupational exposure to this organism, and implement such interventions in future studies. PUBLIC HEALTH RELEVANCE: Methicilin-resistant Staphylococcus aureus (MRSA) has been found in a high proportion of swine and swine workers in studies carried out in Europe and Canada. Recently, our group has identified MRSA in a small study of swine and farmers in Iowa and Illinois. We seek to determine how common MRSA colonization and infection are in Iowa livestock, and to determine if livestock exposure represents a new occupational risk factor for MRSA colonization and infection.