{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T21:40:04Z","timestamp":1790286004189,"version":"4.1.0"},"reference-count":59,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,10]],"date-time":"2024-09-10T00:00:00Z","timestamp":1725926400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Medical University-Sofia","award":["No. 180\/03.08.2023"],"award-info":[{"award-number":["No. 180\/03.08.2023"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Moraxella catarrhalis has been recognized as an important cause of upper respiratory tract and middle ear infections in children, as well as chronic obstructive pulmonary disease and chronic bronchitis in adults. We aim to study the clonal structure, antimicrobial resistance, and serotypes of M. catarrhalis strains recovered from patients of different ages. Nasopharyngeal swabs, middle ear fluid, and sputum samples were collected. In vitro susceptibility testing was performed according to EUCAST criteria. The monoclonal Ab hybridoma technique was used for serotyping. All strains were subjected to MLST. The studied population demonstrated susceptibility to all tested antimicrobials M. catarrhalis strains, with the majority being serotype A (90.4%), followed by B (6.8%), and C (2.7%). We observed a predominant clonal complex CC224 (21.9%) along with other clusters including CC141 (8.2%), CC184 (8.2%), CC449 (6.8%), CC390 (5.5%), and CC67 (2.7%). Two primary founders, namely, ST224 and ST141, were identified. The analyzed genetic lineages displayed diversity but revealed the predominance of two main clusters, CC224 and CC141, encompassing multidrug-resistant sequence types distributed in other regions. These data underscore the need for ongoing epidemiological monitoring of successfully circulating clones and the implementation of adequate antibiotic policies to limit or delay the spread of multidrug-resistant strains in our region.<\/jats:p>","DOI":"10.3390\/ijms25189769","type":"journal-article","created":{"date-parts":[[2024,9,10]],"date-time":"2024-09-10T03:16:51Z","timestamp":1725938211000},"page":"9769","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Phylogenetic Lineages and Diseases Associated with Moraxella catarrhalis Isolates Recovered from Bulgarian Patients"],"prefix":"10.3390","volume":"25","author":[{"given":"Alexandra S.","family":"Alexandrova","sequence":"first","affiliation":[{"name":"Department of Medical Microbiology, Medical Faculty, Medical University of Sofia, 1431 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0429-9252","authenticated-orcid":false,"given":"Vasil S.","family":"Boyanov","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, Medical Faculty, Medical University of Sofia, 1431 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kalina Y.","family":"Mihova","sequence":"additional","affiliation":[{"name":"Department of Medical Chemistry and Biochemistry, Molecular Medicine Center, Medical Faculty, Medical University of Sofia, 1431 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raina T.","family":"Gergova","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, Medical Faculty, Medical University of Sofia, 1431 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1016\/S1286-4579(00)00314-2","article-title":"Moraxella catarrhalis: A review of an important human mucosal pathogen","volume":"2","author":"Karalus","year":"2000","journal-title":"Microbes Infect."},{"key":"ref_2","first-page":"874","article-title":"Co-carriage of Streptococcus pneumoniae and Moraxella catarrhalis among preschool children and its influencing factors","volume":"24","author":"Deng","year":"2022","journal-title":"Zhongguo Dang Dai Er Ke Za Zhi"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1128\/CMR.15.1.125-144.2002","article-title":"Moraxella catarrhalis: From emerging to established pathogen","volume":"15","author":"Verduin","year":"2002","journal-title":"Clin. 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