The Health Burden of A Recently Discovered Borrelia Spirochete

描述（由申请人提供）：我们发现了一种新的螺旋体伯氏疏螺旋体，它在实验室小鼠中引起持续感染，并广泛分布于美国莱姆病的蜱媒伊蚊种群中。初步的遗传和抗原分析表明，该生物是一个密切相关的回归热螺旋体群的成员，最初在日本被描述为宫本氏疏螺旋体。最近的调查提供了令人信服的证据，证明这种螺旋体在俄罗斯引起人类疾病，那里感染宫本氏杆菌的伊蚊蜱的百分比与美国东北部相似。其中一些患者经历了长期的复发性疾病。关于这种新型螺旋体的遗传和抗原特征的基本信息缺乏，诊断工具尚未开发用于临床。虽然目前只有少数人感染宫宫氏杆菌的病例被确认，但我们怀疑在其广泛的地理分布范围内可能存在其他病例，特别是在莱姆病高地方性的美国东北部。因此，我们建议研究宫本氏疏螺旋体与其他伯氏疏螺旋体的抗原关系，以建立更好的诊断方法，并比较东北地区宫本氏疏螺旋体与伯氏疏螺旋体感染的频率和临床表现。由于在莱姆病流行地区，人类接触可能感染宫本氏杆菌的蜱叮咬的程度很高，而且无法用用于诊断莱姆病的相同实验室程序检测感染，因此迫切需要这些信息。由于宫本氏贝氏菌属于螺旋体的回归热组，并引起具有回归热症状的持续性疾病，因此一些归因于莱姆病并被指定为“慢性莱姆病”的疾病的长期发作可能是由于宫本氏贝氏菌感染。

DESCRIPTION (provided by applicant): We have found a new Borrelia spirochete that causes persistent infection in laboratory mice and is widely distributed in field populations of Ixodes tick vectors of Lyme disease throughout the United States. Preliminary genetic and antigen analysis indicates that this organism is a member of a closely related group of relapsing fever spirochetes and was originally described as Borrelia miyamotoi in Japan. Recent investigations provide convincing evidence that this spirochete causes human disease in Russia where the percentages of B. miyamotoi-infected Ixodes ticks are similar to those in the northeastern United States. Some of these patients experienced prolonged, relapsing illness. Basic information is lacking regarding genetic and antigenic characteristics of this novel spirochete and diagnostic tools are not yet developed for clinical use. Although only a few human cases of infection with B. miyamotoi are currently recognized, we suspect that cases may exist elsewhere within its broad geographic distribution and particularly in the northeastern United States where Lyme disease is hyperendemic. Accordingly, we propose to investigate the antigenic relationship between B. miyamotoi and other Borrelia species in order to develop improved diagnostic methods and to compare the frequency and clinical manifestations of B. miyamotoi infection with those of Borrelia burgdorferi in the Northeast. Such information is urgently needed because of the high level of human exposure to bites from ticks potentially infected with B. miyamotoi in Lyme endemic regions and because infection cannot be detected with the same laboratory procedures used to diagnose Lyme disease. Because B. miyamotoi belongs to the relapsing fever group of spirochetes and causes persistent illness with relapsing fever symptoms, it is possible that some prolonged episodes of illness attributed to Lyme disease and designated as "chronic Lyme disease" are due to B. miyamotoi infection. PUBLIC HEALTH RELEVANCE: A new form of I scapularis-borne Borrelia spirochete (B. miyamotoi) is widely distributed in field populations of ticks in the United States but basic information is lacking regarding its antigenic characteristics, diagnostic tools are not yet well developed, and it is unclear whether cases exist beyond Russia where the first few human cases have been described. We propose to investigate the antigenic relationship between this spirochete and other Borrelia species in order to develop improved diagnostic methods, and to compare the seroprevalence and clinical manifestations of B. miyamotoi infection with those of Borrelia burgdorferi. Such information is urgently needed because the organism is found in the same vector tick and mouse reservoir of Borrelia burgdorferi in Lyme endemic regions of the United States and because it is possible that some prolonged episodes of illness attributed to Lyme disease may actually be due to infection with this B. miyamotoi organism.