Coronaviruses are known to cause fatal diseases like Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS) and recently recognised coronavirus disease 19 (COVID-19). It is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a single-stranded RNA virus. This review is done to study the clinical presentation, comorbid conditions in COVID-19 patients. The relevant articles were searched in PubMed, Science direct and special issues in JAMA, and the New England Journal of Medicine. Only selected papers were used for data extraction and synthesis. The exact source of current pandemic of Covid-19 is not known. The main clinical symptoms include fever, dry cough, myalgia, dyspnoea. Other symptoms presented are headache, malaise, chills/rigor and diarrhoea. The mortality rate was high in above 60 years of age with the comorbid conditions. The data analysis revealed varied mortality rates in different regions. The mortality rate of COVID-19 has been highest among elderly individuals with the comorbid conditions.