Surveillance of LGV Chlamydia trachomatis types among men who have sex with men (MSM)

衣原体是由沙眼衣原体（CT）引起的一种常见的性传播感染（STI）。据估计，全世界每年有5000万衣原体新病例，如果不加以治疗，可导致严重并发症，如妇女盆腔炎和不孕症以及男子附睾炎。在过去的十年里，澳大利亚衣原体的诊断急剧增加，与此同时，据报道性风险行为（伴侣数量增加和/或无保护的性行为）激增，特别是在男男性行为（MSM）中。此外，目前在整个西欧爆发了一种侵入性CT菌株，引起性病性淋巴肉芽肿（LGV），目前在美国也报告了病例。LGV可导致严重的肛门生殖器溃疡，从而增加艾滋病毒、丙型肝炎和其他性传播感染的传播。随着国际旅行的增加，在澳大利亚，特别是在男男性行为者中，LGV爆发的可能性增加了。最近，在悉尼和墨尔本性健康中心就诊的男同性恋者中发现了LGV的孤立病例，这表明LGV可能已经在传播。由于我们对澳大利亚流行的CT类型知之甚少，因此很难评估LGV爆发的负担。由于不断增加的CT感染和可能增加的艾滋病毒传播风险，特别是LGV毒株，监测澳大利亚的CT基因型，特别是在男同性恋者中，是很重要的。本研究的目的是通过观察其基因组成来对我们人群中的CT菌株进行分类。来自墨尔本和悉尼的CT阳性标本将用于确定流通中的CT类型，并评估是否存在LGV类型。从这项研究中获得的知识将是新颖和宝贵的，并可大大有助于制定更好的疾病预防和干预战略，包括设计疫苗。

Chlamydia is a common sexually transmitted infection (STI) caused by the bacterium, Chlamydia trachomatis (CT). Annually, 50 million new cases of chlamydia are estimated to occur worldwide which if untreated, can lead to serious complications such as pelvic inflammatory disease and infertility in women and epididymitis in men. Over the past decade, there has been a sharp increase in diagnoses of chlamydia in Australia, coinciding with a reported upsurge in sexual risk behaviour (increased partner numbers and-or practices of unprotected sex), particularly among men who have sex with men (MSM). In addition, there are current outbreaks of an invasive CT strain, causing lymphogranuloma venereum (LGV), throughout Western Europe, with cases now reported in the USA. LGV can lead to severe anogenital ulcers, which can increase transmission of HIV, hepatitis C, and other STIs. With growing international travel, the likelihood of LGV outbreaks in Australia, particularly in MSM, is increased. Recently, isolated cases of LGV have been noted in MSM attending Sydney and Melbourne Sexual Health Centres, indicating LGV is possibly already in circulation. Since we know little about circulating CT types in Australia it would be difficult to assess the burden of an LGV outbreak. Due to increasing CT infections and likely risk of increased HIV transmission, particularly with LGV strains, surveillance of CT genotypes in Australia, especially in MSM, is important. The purpose of this study is to type CT strains in our population by looking at their genetic makeup. CT-positive specimens from Melbourne and Sydney will be used to identify CT types in circulation and to assess if LGV types are present. The knowledge obtained from this study will be novel and invaluable, and could contribute considerably to the development of improved disease prevention and intervention strategies, including the design of vaccines.