The human gut system is extremely vast and varied. The gut is considered the second brain of the human body. It consists of 0-100 trillion micro organisms and their genes regulate the gastrointestinal complex pathways to ensure good health. These are considered good bacteria in the gut or gut microbiome. Interference with a disbalance of the good and bad bacteria may result in disruption of the normal mode of activity of this population. This may result in damage to the gut barrier causing gut issues which may affect the normal lifestyle. 

COVID infection disrupts the gut microbiome 

Coronavirus infection directly interferes with the healthy balance of the microbes in the gut. An NIH- founded team at the New York University school of medicine investigated how coronavirus affects the gut microbes in mice. The study was published just recently in November 2022, found that COVID patients develop imbalances in the gut microbiome which gives antibiotic-resistant bacterial infections a scope to be dominant. 

COVID symptoms are related to the stomach or digestive system and not just confined to the respiratory system. 

We are well aware of the trademark symptoms like cough, fever, and runny nose. But, COVID symptoms are not just confined to the respiratory system but may spread to the digestive system. During the initial wave of COVID, infection people had reported having abdominal pain, diarrhea, and loss of appetite. A study found that up to 34% of COVID patients experience diarrhea. 

The gastro-intestinal link between COVID and stomach 

The covid causing coronavirus enters the intestinal cells using an angiotensin-converting enzyme (ACE-2) protein as a receptor. Once inside it replicates and produces copies of its viral protein. The majority of COVID-19 associated with GI symptoms are mild and self-limiting and include anorexia, nausea, vomiting, and abdominal pain/discomfort. Involvement of the GI tract may directly cause weakness of gut barrier due to covid infection which may lead to malabsoprtion syndrome. This may lead to inflammation of the gut affecting the mucosal integrity and activation of the enteric nervous system. 

The gut microbiome influences the severity of COVID. It has been reported as per records that gut microbiome composition was significantly altered in patients with COVID as compared to non-COVID patients. The study found that COVID depleted the gut bacteria due to immunomodulatory affection.