{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,26]],"date-time":"2026-07-26T10:09:31Z","timestamp":1785060571333,"version":"3.55.0"},"reference-count":27,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,7,22]],"date-time":"2023-07-22T00:00:00Z","timestamp":1689984000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Science Fund at the Ministry of Education and Science of Bulgaria","award":["K\u041f-06-H23\/10"],"award-info":[{"award-number":["K\u041f-06-H23\/10"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Rhinoviruses (RV) are one of the most common causative agents of respiratory infections, with significant socioeconomic impact. RV infections are not notifiable in Bulgaria, and little is known about the different RV genotypes circulating in the country. This study aims to investigate the diversity of RV genotypes that were circulating in Bulgaria in the period 2018\u20132021 in samples from ILI\/ARI patients. Genotype assignment was based on sequencing and phylogenetic analysis of the 5\u2032 untranslated region and the VP4-VP2 region. Out of a total of 1385 nasopharyngeal swabs tested, 166 were RV-positive (RV detection rate: 11.99% (166\/1385)). Those with a cycle threshold &lt;25 were selected for genotyping (n = 63). RV isolates were successfully genotyped and classified into 34 genotypes within Rhinovirus A (RV-A), Rhinovirus B (RV-B) and Rhinovirus C (RV-C) species. Presumptive recombination events between the 5\u2032UTR and VP4-VP2 regions were detected in three of the isolates. RV-A and RV-C were the prevalent RV species, with significantly more frequent detections of RV-A in the years before the COVID-19 pandemic compared to the post-pandemic period, when RV-C prevailed. The present study is the first to determine RV genotypes in Bulgaria and the circulation of RV-C has been described for the first time in the country.<\/jats:p>","DOI":"10.3390\/v15071608","type":"journal-article","created":{"date-parts":[[2023,7,24]],"date-time":"2023-07-24T00:57:30Z","timestamp":1690160250000},"page":"1608","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Rhinovirus Genotypes Circulating in Bulgaria, 2018\u20132021"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4814-4922","authenticated-orcid":false,"given":"Irina","family":"Georgieva","sequence":"first","affiliation":[{"name":"Department of Virology, National Centre of Infectious and Parasitic Diseases, 1233 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6219-8524","authenticated-orcid":false,"given":"Asya","family":"Stoyanova","sequence":"additional","affiliation":[{"name":"Department of Virology, National Centre of Infectious and Parasitic Diseases, 1233 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Svetla","family":"Angelova","sequence":"additional","affiliation":[{"name":"Clinic of Infectious Diseases, University Hospital \u201cProf. Dr. Stoyan Kirkovich\u201d AD, 6003 Stara Zagora, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Neli","family":"Korsun","sequence":"additional","affiliation":[{"name":"Department of Virology, National Centre of Infectious and Parasitic Diseases, 1233 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Savina","family":"Stoitsova","sequence":"additional","affiliation":[{"name":"Department of Virology, National Centre of Infectious and Parasitic Diseases, 1233 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8008-2821","authenticated-orcid":false,"given":"Lubomira","family":"Nikolaeva-Glomb","sequence":"additional","affiliation":[{"name":"Department of Virology, National Centre of Infectious and Parasitic Diseases, 1233 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1128\/JCM.36.2.539-542.1998","article-title":"Viruses and Bacteria in the Etiology of the Common Cold","volume":"36","author":"Makela","year":"1998","journal-title":"J. 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