PDF(Pubmed)
Abstract：
Cryptococcus neoformans and Cryptococcus gattii cause cryptococcosis, a systemic mycosis that infects a wide range of species. Recent molecular biological investigations have allowed for the genotyping of these species, providing more detailed information on their pathogenicity and infection routes. Koalas (Phascolarctos cinereus) are frequently colonized by Cryptococcus spp., but molecular epidemiological studies have yet to be conducted in Japan. Here, we conducted multi-locus sequence typing (MLST) analysis on Cryptococcus spp. colonization isolates obtained from all koalas kept in seven parks across Japan. Out of 46 koalas examined, 10 (22%) were positive for C. gattii and 3 (6.5%) were positive for C. neoformans. All C. gattii isolates belonged to molecular type VGI and were either sequence type (ST) 51 or a novel ST, and all C. neoformans isolates belonged to molecular type VNI and ST23. Despite the frequent movement of koalas between parks, the STs were relatively park-specific, suggesting that the floor of the rearing barns is a source of infection and may act as a reservoir. MLST analysis confirmed that C. gattii was transported, established, and spread by koalas in areas where C. gattii was not originally present. MLST analysis is considered useful in assessing the pathogenicity and tracing the transmission routes of Cryptococcus spp. carried by koalas.IMPORTANCEThis is the first study to conduct a multi-locus sequence typing analysis on Cryptococcus spp. carried by captive koalas in Japan. Cryptococcosis remains a globally high-fatality fungal infection in humans, and captive koalas are known to carry a high percentage of Cryptococcus spp. Through this research, the molecular types and transmission routes of Cryptococcus spp. carried by koalas have been elucidated, revealing the potential role of enclosure flooring as a reservoir. It has been confirmed that Cryptococcus gattii, which is not endemic in Japan, has become established through koalas and is spreading to new individuals in Japan. This study is believed to provide valuable insights into koala conservation and contribute to the One Health approach for Cryptococcosis, a zoonotic infection.
摘要：
新生隐球菌和gattii隐球菌引起隐球菌病，感染多种物种的全身性真菌病。最近的分子生物学研究允许对这些物种进行基因分型，提供有关其致病性和感染途径的更详细信息。考拉（Phascolarctoscinereus）经常被隐球菌属定殖。,但是分子流行病学研究尚未在日本进行。这里,我们对隐球菌进行了多位点序列分型（MLST）分析。从日本七个公园中保存的所有考拉获得的定殖分离株。在检查的46只考拉中，10例（22％）对C.gattii呈阳性，3例（6.5％）对新型C.所有C.gattii分离株都属于分子型VGI，并且是序列型（ST）51或新型ST，所有新生梭菌分离株都属于分子型VNI和ST23。尽管考拉经常在公园之间移动，STs是相对特定于公园的，这表明饲养谷仓的地板是感染源，可能充当水库。MLST分析证实了加蒂梭菌被运输，已建立,并由考拉在C.gattii最初不存在的地区传播。MLST分析被认为可用于评估致病性和追踪隐球菌属的传播途径。由考拉携带。重要意义这是对隐球菌属进行多位点序列分型分析的第一项研究。由日本的圈养考拉携带。隐球菌病仍然是全球高致死率的人类真菌感染，圈养的考拉被认为携带高比例的隐球菌属。通过这项研究,隐球菌属的分子类型和传播途径。考拉携带的考拉已经被阐明，揭示了围栏地板作为水库的潜在作用。已经证实加蒂隐球菌，这在日本不是地方病，已经通过考拉建立起来，并正在传播给日本的新个体。这项研究被认为为考拉保护提供了有价值的见解，并有助于隐球菌病的一种健康方法，人畜共患感染.
