{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T18:39:28Z","timestamp":1790015968952,"version":"4.0.1"},"reference-count":144,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,12,23]],"date-time":"2021-12-23T00:00:00Z","timestamp":1640217600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>The number of obese adults and children is increasing worldwide, with obesity now being a global epidemic. Around 2.8 million people die annually from clinical overweight or obesity. Obesity is associated with numerous comorbid conditions including hypertension, cardiovascular disease, type 2 diabetes, hypercholesterolemia, hypertriglyceridemia, nonalcoholic fatty liver disease, and cancer, and even the development of severe disease after infection with viruses. Over the past twenty years, a number of new viruses has emerged and entered the human population. Moreover, influenza (H1N1)pdm09 virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have caused pandemics. During pandemics, the number of obese patients presents challenging and complex issues in medical and surgical intensive care units. Morbidity amongst obese individuals is directly proportional to body mass index. In this review, we describe the impact of obesity on the immune system, adult mortality, and immune response after infection with pandemic influenza virus and SARS-CoV-2. Finally, we address the effect of obesity on vaccination.<\/jats:p>","DOI":"10.3390\/v14010025","type":"journal-article","created":{"date-parts":[[2021,12,23]],"date-time":"2021-12-23T21:40:21Z","timestamp":1640295621000},"page":"25","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Pandemics of the 21st Century: The Risk Factor for Obese People"],"prefix":"10.3390","volume":"14","author":[{"given":"Miriam","family":"Hanckov\u00e1","sequence":"first","affiliation":[{"name":"Biomedical Research Center, Slovak Academy of Sciences, Institute of Virology, 845 05 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1095-8258","authenticated-orcid":false,"given":"Tatiana","family":"Bet\u00e1kov\u00e1","sequence":"additional","affiliation":[{"name":"Biomedical Research Center, Slovak Academy of Sciences, Institute of Virology, 845 05 Bratislava, Slovakia"},{"name":"Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, 842 15 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1089\/bsp.2009.0729","article-title":"Public health and medical responses to the 1957\u201358 influenza pandemic","volume":"7","author":"Henderson","year":"2009","journal-title":"Biosecur. 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