{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T21:05:09Z","timestamp":1776373509697,"version":"3.51.2"},"reference-count":48,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,12,27]],"date-time":"2021-12-27T00:00:00Z","timestamp":1640563200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/128825\/2017"],"award-info":[{"award-number":["SFRH\/BD\/128825\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["2020.03171.CEECIND"],"award-info":[{"award-number":["2020.03171.CEECIND"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UID\/BIO\/04469\/2020"],"award-info":[{"award-number":["UID\/BIO\/04469\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Understanding the bacterial etiology of otitis media (OM) is important when designing and evaluating the best course of treatment. This study analyzed middle ear fluid (MEF) and nasopharynx (NP) samples collected from 49 children with OM undergoing myringotomy in the northwestern Portuguese district of Braga. A correlation between species in the NP and MEF was observed following pathogen detection by culture and quantitative polymerase chain reaction (qPCR) methods. Bacterial identification using culturing methods showed that Moraxella catarrhalis was the most representative in NP and MEF, followed by Streptococcus pneumoniae. However, qPCR of MEF showed a higher prevalence (61%) of Haemophilus influenzae. S. pneumoniae was not the most frequently identified species, but it still remains one of the leading causes of OM in this region despite 93.9% of the children being vaccinated with the pneumococcal conjugate vaccine. Furthermore, 46% of the samples analyzed by qPCR identified more than two bacterial species. M. catarrhalis and S. pneumoniae were the most frequent combination identified in NP and MEF samples by culturing methods. Additionally, a few NP and MEF samples simultaneously presented the three main otopathogens. These results point out that polymicrobial infections play an important role in OM. Further studies characterizing the serotypes of the strains isolated, their resistance profile, and their biofilm forming ability would help in the development of more targeted strategies against otitis media.<\/jats:p>","DOI":"10.3390\/microorganisms10010054","type":"journal-article","created":{"date-parts":[[2021,12,28]],"date-time":"2021-12-28T01:20:43Z","timestamp":1640654443000},"page":"54","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Identification of the Bacterial Pathogens in Children with Otitis Media: A Study in the Northwestern Portuguese District of Braga"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2495-6026","authenticated-orcid":false,"given":"Maria Daniela","family":"Silva","sequence":"first","affiliation":[{"name":"CEB\u2014Centre of Biological Engineering, LIBRO\u2014Laborat\u00f3rio de Investiga\u00e7\u00e3o em Biofilmes Ros\u00e1rio Oliveira, University of Minho, 4710-057 Braga, Portugal"},{"name":"INL\u2014International Iberian Nanotechnology Laboratory, Avenida Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ant\u00f3nio","family":"Lima","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Hospital de Braga, 4710-243 Braga, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nuno","family":"Mar\u00e7al","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Trofa Sa\u00fade Hospital, 4715-196 Braga, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9630-5463","authenticated-orcid":false,"given":"Lu\u00eds","family":"Dias","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Hospital de Braga, 4710-243 Braga, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5655-0015","authenticated-orcid":false,"given":"Miguel","family":"Gama","sequence":"additional","affiliation":[{"name":"CEB\u2014Centre of Biological Engineering, LIBRO\u2014Laborat\u00f3rio de Investiga\u00e7\u00e3o em Biofilmes Ros\u00e1rio Oliveira, University of Minho, 4710-057 Braga, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8408-8550","authenticated-orcid":false,"given":"Sanna","family":"Sillankorva","sequence":"additional","affiliation":[{"name":"INL\u2014International Iberian Nanotechnology Laboratory, Avenida Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"595","DOI":"10.1080\/1040841X.2019.1660616","article-title":"Otitis media pathogens\u2013A life entrapped in biofilm communities","volume":"45","author":"Silva","year":"2019","journal-title":"Crit. 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