{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T00:42:34Z","timestamp":1783039354365,"version":"3.54.6"},"reference-count":33,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,10,4]],"date-time":"2021-10-04T00:00:00Z","timestamp":1633305600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NEKKEN collaborative research fund and AMED","award":["JP19fm0108001 (Japan Initiative for Global Research Network on Infectious Diseases (J-GRID))"],"award-info":[{"award-number":["JP19fm0108001 (Japan Initiative for Global Research Network on Infectious Diseases (J-GRID))"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Acute bacterial conjunctival infections are common, and this study identified the conjunctival bacterial community in infectious conjunctivitis cases seen at the outpatient clinic of Khanh Hoa General Hospital in Nha Trang, Vietnam from October 2016 through December 2017. Conjunctival swabs were collected and tested using conventional culture, PCR, and 16S ribosomal RNA sequencing. The study included 47 randomly selected patients. More than 98% of all DNA reads represented five bacterial phyla. Three of these phyla constituted 92% of all sequences (Firmicutes (35%), Actinobacteria (31%), and Proteobacteria (26%)). At the genus level, there were 12 common genera that constituted about 61% of all sequence reads. Seven of those genera were common (Streptococcus (10%), Cutibacterium (10%), Staphylococcus (7%), Nocardioides (7%), Corynebacterium 1 (5%), Anoxybacillus (5%), and Acinetobacter (5%)), which encompassed 49% of all reads. As for diversity analysis, there was no difference on PERMANOVA analysis (unweighted UniFrac) for sex (p = 0.087), chemosis (p = 0.064), and unclassified eyedrops (p = 0.431). There was a significant difference in cases with bilateral conjunctivitis (p = 0.017) and for using antibiotics (p = 0.020). Of the predominant phyla, Firmicutes had the highest abundance in bacterial conjunctivitis in this study. Pseudomonas as a resident commensal microbiota may have an important role in the prevention of infection.<\/jats:p>","DOI":"10.3390\/microorganisms9102095","type":"journal-article","created":{"date-parts":[[2021,10,8]],"date-time":"2021-10-08T21:23:55Z","timestamp":1633728235000},"page":"2095","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Conjunctival Sac Microbiome in Infectious Conjunctivitis"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6346-6690","authenticated-orcid":false,"given":"Yasser Helmy","family":"Mohamed","sequence":"first","affiliation":[{"name":"Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9584-4323","authenticated-orcid":false,"given":"Masafumi","family":"Uematsu","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshitomo","family":"Morinaga","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hien-Anh Thi","family":"Nguyen","sequence":"additional","affiliation":[{"name":"National Institute of Hygiene and Epidemiology, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michiko","family":"Toizumi","sequence":"additional","affiliation":[{"name":"Department of Pediatric Infectious Diseases, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daisuke","family":"Sasaki","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katsunori","family":"Yanagihara","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Duc-Anh","family":"Dang","sequence":"additional","affiliation":[{"name":"National Institute of Hygiene and Epidemiology, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takashi","family":"Kitaoka","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lay-Myint","family":"Yoshida","sequence":"additional","affiliation":[{"name":"Department of Pediatric Infectious Diseases, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1477","DOI":"10.1136\/bmj.293.6560.1477","article-title":"Eye disease at a community health centre","volume":"293","author":"Dart","year":"1986","journal-title":"Br. 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