COVID -19, first reported in Wuhan, China, strikes the world hard as a pandemic by spreading up to 213 countries. Bangladesh is also facing its havoc with the death of 3000 among 229,185 cases at its 141st day. Most are mild cases presenting with influenza-like illness with expected recovery. According to World Health Organization, the overall global case fatality rate is currently estimated to be 2.9%. However, patients having severe or critical illness presenting with severe respiratory distress, ARDS or shock suffer most with mortality rates of 49.0-61.5%. Studies suggest that there are mild or severe cytokine storms in severe patients, which is an important cause of death. An exaggerated and uncontrolled release of pro-inflammatory mediators by an overly activated immune system is known as cytokine storms (CS) or cytokine release syndrome (CRS) which has an important role in the hemodynamic insults seen in very ill COVID-19 patients. This aberrant release of pro-inflammatory cytokines causes lung damage, myocarditis, acute kidney injury, etc. In this study, the investigators aim to estimate the burden of cytokines and their correlation with the magnitude of the severity of COVID-19 illness in Bangladeshi adults.

Background:

1. Burden: COVID -19, first reported in Wuhan, China, strikes the world hard as a pandemic by spreading up to 213 countries. Bangladesh is also facing its havoc with the death of 3000 among 229,185 cases at its 141st day. Most are mild cases presenting with influenza-like illness with expected recovery. According to World Health Organization, the overall global case fatality rate is currently estimated to be 2.9%. However, patients having severe or critical illness presenting with severe respiratory distress, ARDS or shock suffer most with mortality of 49.0-61.5%. Studies suggest that there are mild or severe cytokine storms in severe patients, which is an important cause of death. An exaggerated and uncontrolled release of proinflammatory mediators by an overly activated immune system is termed as cytokine storm (CS). Studies depicting that there might be an important relationship between SARS-CoV-2 and gut microbiota, as a marker to predict ARDS, can corroborate with the disease severity and outcomes of COVID-19.
2. Knowledge gap: Cytokine storm (CS) has an important role in the hemodynamic insults seen in very ill COVID-19 patients. In Bangladesh, no study has been conducted to evaluate the level of cytokines and the gut microbiota in COVID-19 patients presenting with different level of severity and their possible correlation with COVID-19.
3. Relevance: It will explore the role of CS and gut microbiota in COVID-19 illness severity. Thus, the results of the study will improve our knowledge and understanding of the problem, and thereby finding their solutions.

Objectives:

To estimate the burden of 'Cytokine Storm' and its correlation with the magnitude of the severity of COVID-19 illness in Bangladeshi adults.

Methods:

This will be a prospective observational study in adults aged ≥18 years old with COVID-19 having mild /moderate/severe/critical symptoms. The investigators will measure their cytokine (IL 6, TNF-Alpha, and IL1 Beta) levels and investigate gut microbiota in addition to regular laboratory tests at different time points of illness.

Inclusion Criteria:

1. Adults aged ≥18 years,
2. Informed consent obtained for participation,
3. A mild, moderate or severe (±critical cases) RT-PCR confirmed COVID-19 cases,
4. RT-PCR negative healthy volunteers.

Exclusion Criteria:

The largest diarrheal hospital in the world, the icddr,b Dhaka Hospital admits and treats the general population from Dhaka city with complaints of diarrhea, pneumonia, and malnutrition. For this COVID-19 pandemic, it is also treating its staff and their near relatives in addition to the general patients reporting to the hospital. icddr,b Dhaka hospital manage patients according to clinical condition, and refer patients to appropriate COVID-19 facility if deemed necessary.