{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T05:09:56Z","timestamp":1789016996306,"version":"build-2803163510"},"reference-count":43,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,10,5]],"date-time":"2021-10-05T00:00:00Z","timestamp":1633392000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Instituto de Salud Carlos III, Spain and RICET [RD16\/0027\/0001 project, from Programa Redes Tem\u00e1ticas de Investigaci\u00f3n Cooperativa, FIS (Ministerio Espa\u00f1ol de Salud, Madrid, Spain), FEDER.","award":["PI18\/01380"],"award-info":[{"award-number":["PI18\/01380"]}]},{"name":"Infectious Diseases and Tropical Medicine Research Center","award":["23422"],"award-info":[{"award-number":["23422"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Free-living amoeba (FLA) are ubiquitously distributed in the environment. However, they are also the causative agents of opportunistic infections in humans and other animals. A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. Moreover, FLA have been detected in various biofilms around the world. Therefore, the present study aimed to check for presence of FLA in samples from household biofilms in Iran and to characterize them at the molecular level. A total of 69 biofilm samples collected from showerheads, kitchen areas, and bathroom sinks were analyzed. Positive samples for FLA were characterized at the morphological and molecular levels. Furthermore, the results of morphology analysis indicated that 26.08% (18\/69) of biofilm samples were positive for Acanthamoeba spp., Vermamoeba genus, and Vahlkampfiids. According to sequence analysis, five strains of Acanthamoeba isolates related to the T4 genotype and two strains belonged to the T2 genotype. In addition, the pathogenic potential of Acanthamoeba-positive isolates was conducted using the tolerance ability test. The results of BLASTn of Vermamoeba sequences were similar to what was expected for Vermamoeba vermiformis. The above-mentioned reasons revealed that the relative high contamination of household biofilm samples with FLA may pose a risk for people using soft contact lenses and for patients with traumatic cataract. Our finding proposes that filtration should be performed in shower heads and indicates the need to monitor people at increased risk of Acanthamoeba keratitis.<\/jats:p>","DOI":"10.3390\/microorganisms9102098","type":"journal-article","created":{"date-parts":[[2021,10,8]],"date-time":"2021-10-08T21:23:55Z","timestamp":1633728235000},"page":"2098","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Molecular Identification of Pathogenic Free-Living Amoeba from Household Biofilm Samples in Iran: A Risk Factor for Acanthamoeba Keratitis"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8628-5240","authenticated-orcid":false,"given":"Maryam","family":"Norouzi","sequence":"first","affiliation":[{"name":"Department of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran 11369, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reza","family":"Saberi","sequence":"additional","affiliation":[{"name":"Department of Medical Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari 48175, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3158-6350","authenticated-orcid":false,"given":"Maryam","family":"Niyyati","sequence":"additional","affiliation":[{"name":"Infectious Diseases and Tropical Medicine Research Center, Shahid Beheshti University of Medical Sciences, Tehran 11369, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacob","family":"Lorenzo-Morales","sequence":"additional","affiliation":[{"name":"Instituto Universitario de Enfermedades Tropicales y Salud P\u00fablica de Canarias (IUETSPC), Universidad de La Laguna (ULL), Avda. Astrof\u00edsico Fco. S\u00e1nchez s\/n, 38203 San Crist\u00f3bal de La Laguna, Spain"},{"name":"Red de Investigaci\u00f3n Cooperativa en Enfermedades Tropicales (RICET), 28006 Madrid, Spain"},{"name":"Departamento de Obstetricia y Ginecolog\u00eda, Pediatr\u00eda, Medicina Preventiva y Salud P\u00fablica, Toxicolog\u00eda, Medicina Legal y Forense y Parasitolog\u00eda, Universidad de La Laguna (ULL), 38200 San Crist\u00f3bal de La Laguna, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hamed","family":"Mirjalali","sequence":"additional","affiliation":[{"name":"Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran 11369, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marziye","family":"Fatemi","sequence":"additional","affiliation":[{"name":"Department of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran 11369, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ehsan","family":"Javanmard","sequence":"additional","affiliation":[{"name":"Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran 14114, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seyed Ahmad","family":"Karamati","sequence":"additional","affiliation":[{"name":"Department of Medical Parasitology and Mycology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University, Tehran 57169, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"782","DOI":"10.1017\/S0031182020000487","article-title":"Free-living amoebae and their relationship to air quality in hospital environments: Characterization of Acanthamoeba spp. obtained from air-conditioning systems","volume":"147","author":"Wopereis","year":"2020","journal-title":"Parasitology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"240","DOI":"10.1016\/j.exppara.2017.09.016","article-title":"Molecular identification of waterborne free living amoebae (Acanthamoeba, Naegleria and Vermamoeba) isolated from municipal drinking water and environmental sources, Semnan province, north half of Iran","volume":"183","author":"Javanmard","year":"2017","journal-title":"Exp. 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