en علوم پایه پزشکی Basic Medical Sciences مروری Review Article <div style="text-align: justify;"><span style="font-size:11pt"><span style="line-height:150%"><span sans-serif="" style="font-family:Calibri,"><span style="font-size:9.0pt"><span style="line-height:150%">Vitamin A is fat-soluble compounds of retinoid derivate, consisting of retinol, retinal, and retinyl esters. Vitamin A also affects cell growth and differentiation, playing a critical role in the normal formation and function of the heart, lungs, kidneys, and other organs. According to the role of vitamin A in enhancing immune function, it is known as an anti-inflammatory agent. Also, vitamin A supplementation by reducing morbidity and mortality in different infectious diseases, such as measles, diarrheal disease, measles-related pneumonia, human immunodeficiency virus infection, and malaria considered as a crucial factor against infection. So vitamin A deficiency can be life-threatening, because of impairing the response to infection and significant risk of development of severe respiratory infections in infants and young children. In this paper, we have discussed the effects of vitamin A in modulating immune responses in viral infections and the direct effects of this vitamin on viral replication by comparing its role during different types of viral infections</span></span><span dir="RTL" lang="FA" style="font-size:9.0pt"><span style="line-height:150%"><span arial="" style="font-family:">.</span></span></span><span style="font-size:9.0pt"><span style="line-height:150%"></span></span></span></span></span></div> Vitamin A,COVID-19,DNA viruses,RNA viruses, 67 83 http://goums.ac.ir/jorjanijournal/browse.php?a_code=A-10-865-2&slc_lang=en&sid=1 Emad Behboudi Jorjani Journal emadbehboudi69@gmail.com 10031947532846008081 10031947532846008081 No Department of Microbiology, Golestan University of Medical Sciences, Gorgan, Iran Parisa Zeynali Parisazeinali751@gmail.com 10031947532846008082 10031947532846008082 No Department of Biochemistry and Biophysics, Metabolic Disorders Research Center, School of Medicine, Golestan University of Medical Science, Gorgan, Iran Niloofar Zahedian Nezhad behboudi.e@goums.ac.ir 10031947532846008083 10031947532846008083 No Department of Microbiology, Golestan University of Medical Sciences, Gorgan, Iran Vahideh Hamidi Sofiani hamidi.v@goums.ac.ir 10031947532846008084 10031947532846008084 Yes Department of Microbiology, Golestan University of Medical Sciences, Gorgan, Iran