Tone Tønjum, Vinicius da Silva Franklin-Duarte, Johan Christian Berild, Konstantina Gartzonika, Eirini Christaki, Viktoria Eirini Mavromanolaki, Sofia Maraki, Anastasia Spiliopoulou, Nikolaos Giormezis, Gergana Lengerova, Yordan Kalchev, Ana Budimir, Branka Bedenić, Zana Rubic, Antonija Saskor, Karla Milanovic, Monica Licker, Corina Musuroi, Mateja Pirs, Ivana Velimirovic, Michael Berktold, Adriána Krajčíková, Anezka Gryndlerova, Pavel Drevinek, Miroslava Htoutou Sedláková, Milan Kolář, Monika Brzychczy-Wloch, Aldona Olechowska-Jarząb, Małgorzata Brauncajs, Filip Bielec, Dominika Seliga-Gąsior, Edyta Podsiadly, Kristian Riesbeck, Hanna-Sofia Andersson, Paulo Bastos, Truls Michael Leegaard, Asger Nellemann Rasmussen, Kristian Schønning, Stefan Glöckner, Jürgen Rödel, Sara Posadas-Cantera, Mohamed Tarek Badr, Tim Kintzinger, Frieder Schaumburg, Philipp Thelen, Axel Hamprecht, Anna Dudakova, Jonathan Jantsch, Katharina Hoffmann, Achim J Kaasch, Damien Jacot, Gilbert Greub, Jessica Landi, Simone Ambretti, Sara Comini, Sofia Chiatamone Ranieri, Enrica Serretiello, Gianluigi Franci, Teresa Fasciana, Rogier Schade, Erlangga Yusuf, Stefanie van Kleef-van Koeveringe, Sarah Vandamme, Alexia Verroken, Hector Rodriguez-Villalobos, Gregory Strubbe, Stien Vandendriessche, Pauline Rabeau, Stéphane Corvec, Damien Dubois, Pauline Floch, Delphine Chainier, Olivier Barraud, Assaf Mizrahi, Célia Bacho, Coralie Bouchiat, Tayssir Fatah, Hélène Marchandin, Vincent Jean-Pierre, Saied Ali, Sinead O'Donnell, Maeve Doyle, Zachary Ramsamaroo, Clarice Egan, Sinead McNicholas, Kristján Orri Helgason, Betigül Öngen, Bahar Akgün Karapınar, Özlem Oyardı, Burak Aksu, Javier Colomina-Rodriguez, Ignacio Torres, Raul Gilarranz Luengo, Maria Nieves Larrosa Escartín, Maria Belen Viñado Perez, Ana Verónica Halperin, Rafael Cantón, Miguel Seruca, Vasco Santos Mendes, Yuliya Volovetska, José Melo Cristino, Gabriele Bianco, Cristina Costa, Matteo Boattini
The epidemiology of Moraxella species from BCs in Europe showed age-group-specific differences in species distribution and generally favourable antimicrobial susceptibility patterns. Phylogenomic data corroborated recent taxonomic revisions, highlighting the need for improved diagnostics, harmonized nomenclature and sustained surveillance to inform management and stewardship of Moraxella bacteraemia.
INTRODUCTION: Moraxella species are fastidious Gram-negative bacteria capable of causing opportunistic infections, including bloodstream infections, especially in immunocompromised patients. Data on their epidemiology, antimicrobial susceptibility, and phylogenomics in Europe remains limited.
METHODS: We conducted a multicentre, retrospective, observational study across 56 European hospital centres between January 1st 2020 and December 31st 2024. All Moraxella species isolated from blood cultures (BCs) were included. Species distribution and antimicrobial susceptibility profiles were analysed. We also performed a phylogenomic analysis of Moraxella genomes deposited in GenBank.
RESULTS: A total of 709 Moraxella isolates were included. Moraxella osloensis (61.1%; n = 433/709) and Moraxella catarrhalis (20.4%; n = 145/709) were the most frequently identified species, followed by Moraxella nonliquefaciens (6.5%; n = 46/709) and Moraxella atlantae (4.8%; n = 34/709). Species distribution differed by age. M. catarrhalis was predominant in paediatric patients, whereas M. atlantae was more common in adults. Most isolates showed > 90% susceptibility to amoxicillin/clavulanate, cefotaxime, fluoroquinolones, and trimethoprim/sulfamethoxazole. Cefotaxime resistance in M. osloensis was more frequent in adults than in children (49% vs. 8%, p = 0.009). Phylogenomic analysis demonstrated the distinction of a core Moraxella group from the divergent Faucicola lineage, with M. osloensis and M. atlantae clustering within the latter.
CONCLUSIONS: The epidemiology of Moraxella species from BCs in Europe showed age-group-specific differences in species distribution and generally favourable antimicrobial susceptibility patterns. Phylogenomic data corroborated recent taxonomic revisions, highlighting the need for improved diagnostics, harmonized nomenclature and sustained surveillance to inform management and stewardship of Moraxella bacteraemia.