Document Type : Review Article


1 Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran

2 Biotechnology and Biological Science Research Center, Faculty of Science, Shahid Chamran University of Ahvaz, Iran


NCP (new coronavirus pneumonia) was discovered in Wuhan towards the end of 2019 and quickly spread throughout the city. The infection was identified as a novel coronavirus, and the World Health Organization (WHO) called it coronavirus disease-19 (COVID-19). Most people with this infection can experience mild to severe and even fatal symptoms after a period of disease incubation of 4 to 14 days. In up to 10% of patients, gastrointestinal symptoms such as nausea and diarrhea, as well as associated abdominal discomfort, may occur before respiratory symptoms. Several SARS-CoV-2 variations have been identified during the epidemic, however, only a handful are deemed variants of concern (VOCs) by the WHO due to their worldwide public health effect. In this article, we looked at new mutations in COVID-19 as well as the adverse effects of the virus on the cardiovascular and gastrointestinal tract. The discovery of these novel SARS-CoV-2 variations threatens to undo the substantial success made so far in restricting the spread of this viral disease, despite the extraordinary speed with which vaccines against COVID-19 have been developed and vigorous worldwide mass immunization efforts. Through mechanisms involving the dysregulated ACE 2 receptor and TMPRSS2, the SARS-CoV-2 virus has the potential to induce significant systemic disease in the GI tract, liver, biliary tract, and pancreas. Due to the observation of new and daily mutations of this dangerous virus, the definitive treatment of this disease is becoming more and more difficult and facing major challenges that it requires many clinical trials and researches.  

Graphical Abstract

When successive viral mutations prevent definitive treatment of COVID-19


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ِDr. Mohammad Reza Mohammadi
Tarbiat Modares University

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