{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T22:27:08Z","timestamp":1790720828393,"version":"4.1.0"},"reference-count":103,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,4,26]],"date-time":"2023-04-26T00:00:00Z","timestamp":1682467200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>In recent decades, the improvement of traditional vaccines has meant that we have moved from inactivated whole virus vaccines, which provoke a moderate immune response but notable adverse effects, to much more processed vaccines such as protein subunit vaccines, which despite being less immunogenic have better tolerability profiles. This reduction in immunogenicity is detrimental to the prevention of people at risk. For this reason, adjuvants are a good solution to improve the immunogenicity of this type of vaccine, with much better tolerability profiles and a low prevalence of side effects. During the COVID-19 pandemic, vaccination focused on mRNA-type and viral vector vaccines. However, during the years 2022 and 2023, the first protein-based vaccines began to be approved. Adjuvanted vaccines are capable of inducing potent responses, not only humoral but also cellular, in populations whose immune systems are weak or do not respond properly, such as the elderly. Therefore, this type of vaccine should complete the portfolio of existing vaccines, and could help to complete vaccination against COVID-19 worldwide now and over the coming years. In this review we analyze the advantages and disadvantages of adjuvants, as well as their use in current and future vaccines against COVID-19.<\/jats:p>","DOI":"10.3390\/vaccines11050902","type":"journal-article","created":{"date-parts":[[2023,4,26]],"date-time":"2023-04-26T04:42:54Z","timestamp":1682484174000},"page":"902","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Adjuvants for COVID-19 Vaccines"],"prefix":"10.3390","volume":"11","author":[{"given":"Javier","family":"Castrodeza-Sanz","sequence":"first","affiliation":[{"name":"National Influenza Centre, 47005 Valladolid, Spain"},{"name":"Preventive Medicine and Public Health Unit, Hospital Cl\u00ednico Universitario de Valladolid, 47003 Valladolid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4725-6663","authenticated-orcid":false,"given":"Iv\u00e1n","family":"Sanz-Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"National Influenza Centre, 47005 Valladolid, Spain"},{"name":"Instituto de Estudios de Ciencias de la Salud de Castilla y Le\u00f3n, ICSCYL, 42002 Soria, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5357-6340","authenticated-orcid":false,"given":"Jose M.","family":"Eiros","sequence":"additional","affiliation":[{"name":"National Influenza Centre, 47005 Valladolid, Spain"},{"name":"Microbiology Unit, Hospital Cl\u00ednico Universitario de Valladolid, 47003 Valladolid, Spain"},{"name":"Microbiology Unit, Hospital Universitario R\u00edo Hortega, 47013 Valladolid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1016\/j.bsheal.2020.11.002","article-title":"SARS-CoV-2: A critical review of its history, pathogenesis, transmission, diagnosis and treatment","volume":"2","author":"Sofi","year":"2020","journal-title":"Biosaf. 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