The clinical syndrome caused by SARS-CoV-2 was called COVID-19 and became a pandemic from March 2020. Fever, dry cough, and dyspnoea are the predominant clinical manifestations of the disease. However, symptoms such as diarrhea, nausea, vomiting, and abdominal discomfort can also be found in infected patients. Despite the increased prevalence since the second phase of the recent epidemic in China, scientific evidence on the gastrointestinal manifestations of COVID-19 has received little attention. This study aimed to report gastrointestinal signs and pathological findings in patients with COVID-19, in addition to discussing the possibility of fecal transmission. SARS-CoV-2 penetrates gastrointestinal epithelial cells, making patients feces potentially infectious. Although viral RNA can be detected in feces, it is not clear whether fecal-oral transmission occurs. The gastrointestinal characteristics and abdominal manifestations of COVID-19 were reviewed based on case reports and retrospective clinical studies related to the digestive system. It is essential to know that, as the pandemic spreads, new studies are published, and knowledge about gastrointestinal symptoms is better known and reported.

SARS-CoV-2, a severe acute respiratory syndrome caused by Coronavirus 2, discovered in 2019 in China, is responsible for the current pandemic declared by the WHO since March 2020. The clinical syndrome caused by Covid-19 has a broad spectrum of severity. The most common clinical manifestations are fever, dry cough, dyspnea, fatigue, and anosmia. The virus binds to receptors for angiotensin-converting enzyme 2 (ECA2) and serine protease TMPRSS2 for protein S initiation, which are expressed not only in the lungs but also in the liver, colonic, esophageal and biliary epithelial cells. In this context, the liver is a potential target for COVID-19 infection. Liver damage occurs during the course and treatment of viral infection in patients with or without previous liver disease. Therefore, the characteristics of liver injury associated with COVID-19 were reviewed based on research related, in the context of the pandemic.

Exposure to childhood physical abuse, sexual abuse, emotional abuse, and neglect have been found to have a positive association with drug use. Various studies have demonstrated how individuals may turn to drugs as a form of coping. However, this is a negative form of coping, which can take a toll on one’s mental state and even impact families and society. Studies have reported that a higher number of adverse childhood experiences (ACEs) have a stronger association with substance use later in life [1,3]. Recent research has also demonstrated those who experienced childhood neglect also displayed anxiety or depression, which might suggest a reason for the connection between the negligence and drug use [14]. There is also research that shows that childhood maltreatment could influence one’s susceptibility to drugs and the structural remodeling of the brain [4]. Various types of drugs have been used in association with childhood trauma; however, no single drug was reported to have a greater association than the others. Substance abuse has been a rising issue over the years. With the understanding that childhood trauma could contribute to the onset of drug use, it is essential to gain a better knowledge of the specific types of substance abuse linked to childhood trauma. Future examination of this topic can help raise awareness and educate society on the effects of childhood trauma and how to prevent drug use associated with it.

Epigenetics is considered as the science of hereditary phenotype which does not encompass amendment in the DNA. This occurs through chemical processes that modify the phenotype, without altering the genotype. A large number of studies showed that metabolic diseases are highly associated with epigenetic alterations suggesting that epigenetic factors may play a central role in cancer. Recent advancements in the rapidly evolving field of cancer epigenetics have shown extensive reprogramming of every component of the epigenetic machinery in cancer including DNA methylation, histone modifications, nucleosome positioning and non-coding RNAs, specifically microRNA expression. Studies of the mechanism(s) of epigenetic regulation and its reversibility have resulted in the identification of novel targets that may be useful in developing new strategies for the prevention and treatment of cancer.