Fields Barry S, Benson Robert F, Besser Richard E
Respiratory Diseases Branch, Division of Bacterial and Mycotic Diseases, National Center for Infectious Disease, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
Clin Microbiol Rev. 2002 Jul;15(3):506-26. doi: 10.1128/CMR.15.3.506-526.2002.
There is still a low level of clinical awareness regarding Legionnaires' disease 25 years after it was first detected. The causative agents, legionellae, are freshwater bacteria with a fascinating ecology. These bacteria are intracellular pathogens of freshwater protozoa and utilize a similar mechanism to infect human phagocytic cells. There have been major advances in delineating the pathogenesis of legionellae through the identification of genes which allow the organism to bypass the endocytic pathways of both protozoan and human cells. Other bacteria that may share this novel infectious process are Coxiella burnetti and Brucella spp. More than 40 species and numerous serogroups of legionellae have been identified. Most diagnostic tests are directed at the species that causes most of the reported human cases of legionellosis, L. pneumophila serogroup 1. For this reason, information on the incidence of human respiratory disease attributable to other species and serogroups of legionellae is lacking. Improvements in diagnostic tests such as the urine antigen assay have inadvertently caused a decrease in the use of culture to detect infection, resulting in incomplete surveillance for legionellosis. Large, focal outbreaks of Legionnaires' disease continue to occur worldwide, and there is a critical need for surveillance for travel-related legionellosis in the United States. There is optimism that newly developed guidelines and water treatment practices can greatly reduce the incidence of this preventable illness.
军团病首次被发现25年后，临床对其的认知水平仍然较低。病原体嗜肺军团菌是具有迷人生态学特性的淡水细菌。这些细菌是淡水原生动物的细胞内病原体，并利用类似机制感染人类吞噬细胞。通过鉴定使该生物体能够绕过原生动物和人类细胞内吞途径的基因，在阐明嗜肺军团菌发病机制方面取得了重大进展。可能共享这种新型感染过程的其他细菌有伯氏考克斯体和布鲁氏菌属。已鉴定出40多个嗜肺军团菌物种和众多血清群。大多数诊断测试针对的是导致大多数已报告人类军团病病例的物种，即嗜肺军团菌血清1型。因此，缺乏关于其他嗜肺军团菌物种和血清群所致人类呼吸道疾病发病率的信息。尿液抗原检测等诊断测试的改进无意中导致用于检测感染的培养方法使用减少，从而导致军团病监测不全面。军团病的大型局部暴发在全球范围内仍时有发生，美国迫切需要对与旅行相关的军团病进行监测。人们乐观地认为，新制定的指南和水处理措施能够大幅降低这种可预防疾病的发病率。
