Servicio Microbiología Clínica y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain.
Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.
Sci Rep. 2019 Mar 18;9(1):4687. doi: 10.1038/s41598-019-40525-6.
Transmission of Beijing Mycobacterium tuberculosis can be investigated based on genotypic analysis of clinical isolates. A Beijing strain began to spread on Gran Canaria Island, Spain, at the end of the last century. In 1996, only 3 years after its importation to the island, its frequency had increased to 27.1% of all the isolates. The strain was tracked during the following years, and the most recent data obtained corresponded to 2007-8, when its presence continued to be alarming (21%). In the current study, we updated data on the distribution of this strain 20 years (2013-2014) after it was first detected on the island and extended the analysis for the first time to all the mycobacteriology laboratories covering the population of the Canary Island archipelago. Rapid updating was enabled by means of 2 different strain-specific PCRs: one targeting a peculiar feature of the strain, which was identified based on an IS6110 copy mapping in the Rv2180c gene, and a newly defined strain-specific single nucleotide polymorphism, which was identified by whole-genome sequencing. The results showed that the strain has remained highly prevalent (20.90% of all isolates), has spread throughout the neighbouring islands, and has also reached high representativeness in them (11-32%).
根据临床分离株的基因型分析可以研究北京分枝杆菌的传播。上世纪末，西班牙大加那利岛开始出现北京菌株。1996 年，该菌株传入该岛仅 3 年后，其频率已上升至所有分离株的 27.1%。随后的几年中对该菌株进行了追踪，最新数据可追溯到 2007-2008 年，当时其存在仍然令人担忧（21%）。在本研究中，我们在该菌株首次在岛上发现 20 年后（2013-2014 年）更新了有关其分布的数据，并首次将分析扩展到涵盖加那利群岛人口的所有分枝杆菌学实验室。通过使用 2 种不同的菌株特异性 PCR 实现了快速更新：一种针对该菌株的一个特殊特征，该特征是基于 Rv2180c 基因中 IS6110 拷贝映射鉴定的；另一种是新定义的菌株特异性单核苷酸多态性，是通过全基因组测序鉴定的。结果表明，该菌株仍然高度流行（所有分离株的 20.90%），已蔓延到邻近岛屿，并且在这些岛屿上也具有很高的代表性（11-32%）。
