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Both influenza and SARS-CoV-2 viruses share many similarities in their transmission and their cellular tropism for replication in the human respiratory tract. However, the complex intricacies and multi-faceted dynamics of how the two pathogens interact to ensure their survival in the same lung microenvironment are still unclear. In addition, clinical studies on influenza co-infections in COVID-19 patients do not provide conclusive evidence of how influenza co-infection mechanistically modifies disease outcomes of COVID-19. This review discusses various viral as well as host factors that potentially influence the survival or synergism of these two respiratory pathogens in the infected lung microenvironment.<\/jats:p>","DOI":"10.3390\/v16050793","type":"journal-article","created":{"date-parts":[[2024,5,16]],"date-time":"2024-05-16T09:30:03Z","timestamp":1715851803000},"page":"793","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["SARS-CoV-2 and Influenza Co-Infection: Fair Competition or Sinister Combination?"],"prefix":"10.3390","volume":"16","author":[{"given":"Narasaraju","family":"Teluguakula","sequence":"first","affiliation":[{"name":"Adichunchanagiri Institute of Medical Sciences, Adichunchanagiri University, Mandya 571448, Karnataka, India"},{"name":"Department of Microbiology, Immunology and Biochemistry, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2634-6213","authenticated-orcid":false,"given":"Vincent T. K.","family":"Chow","sequence":"additional","affiliation":[{"name":"Infectious Diseases Translational Research Program, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore 119228, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mirazkar Dasharatharao","family":"Pandareesh","sequence":"additional","affiliation":[{"name":"Adichunchanagiri Institute of Medical Sciences, Adichunchanagiri University, Mandya 571448, Karnataka, India"},{"name":"Department of Biochemistry, Adichunchanagiri School of Natural Sciences, Adichunchanagiri University, B.G Nagara 571448, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Venkatesha","family":"Dasegowda","sequence":"additional","affiliation":[{"name":"Adichunchanagiri Institute of Medical Sciences, Adichunchanagiri University, Mandya 571448, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vidyasagar","family":"Kurrapotula","sequence":"additional","affiliation":[{"name":"Adichunchanagiri Institute of Medical Sciences, Adichunchanagiri University, Mandya 571448, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shivaramu M.","family":"Gopegowda","sequence":"additional","affiliation":[{"name":"Adichunchanagiri Institute of Medical Sciences, Adichunchanagiri University, Mandya 571448, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8004-282X","authenticated-orcid":false,"given":"Marko","family":"Radic","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Immunology and Biochemistry, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,16]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2024, April 30). 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