Extensive Studies of Legionella Strains Isolated from the Environmental Objects during Preparation and Holding of Mass Events in the Russian Federation in 2013-2014

Abstract

Objective of the work was to conduct an extended study of Legionella strains isolated from epidemiologically significant environmental objects during the preparation and conduct of mass events in the territory of the Russian Federation in 2013-2014 . Materials and methods. Studied were 53 strains of Legionella pneumophila, isolated from epidemiologically significant objects during the preparation and conduct of a number of mass events (ME): XXVII World Summer Universiade, XXII Olympic Winter Games and XI Paralympic Winter Games, Sochi; Summer Health Promotion Campaign in 2014, Republic of Crimea; IV Caspian Summit, Astrakhan, 2014. Strains were analyzed using multilocus sequencing, time-of-flight mass spectrometry (MALDI-ToF-MS) and atomic force microscopy. Legionella strains were typed by multilocus sequencing in accordance with the algorithm of the European Legionellosis Research Group “Sequence-Based Typing protocol for epidemiological typing of L. pneumophila". Results and discussion. Strains of L. pneumophila, legionellosis agent, were isolated in the territory of the Republic of Crimea, Moscow, Kazan, Sochi, Astrakhan and characterized. According to the results of slide agglutination, 17 L. pneumophila strains were assigned to 1 serogroup , 37 - to 2-14 serogroups. Based on the data obtained by multilocus sequencing, in accordance with the algorithm of the European Working Group on Legionellosis Surveillance, allelic profiles of all the studied L. pneumophila strains were identified; their belonging to 7 sequence types was established. Using the method of time-of-flight mass spectrometry, legionella strains were characterized, their protein profiles were studied, and a database was formed. Using the method of scanning probe microscopy, information was obtained on the morphology of the cells of 18 legionella strains and the features of their surface structures. Using the methods of multilocus sequencing, time-of-flight mass spectrometry, and atomic force microscopy, molecular-genetic, proteomic, and morphometric features of Legionellosis pathogen strains that circulate in epidemiologically significant sites in the Russian Federation were determined.

Keywords

• legionellosis
• mass events
• <i>legionella pneumophila</i>
• monitoring
• bacteriological method
• multilocus sequencing
• time-of-flight mass spectrometry
• atomic force microscopy