COVID-19: Evolution and Prevention by Wimalawansa SJ* in Crimson Publishers: Trends in Telemedicine & E-health Advanced age, having comorbidities, and vitamin D deficiency are three most important reasons for increased vulnerability to COVID-19 and also worsen complications and increase the risk of death. Despite the vast amount of information available and lessons learned, many countries are still not fully utilizing these to manage secondary peaks of COVID-19 infection. Factors associated with worse COVID-19 prognosis include, older age, ethnicity, male sex, having comorbidities, obesity, diabetes, hypertension, and smoking; all these are associate with vitamin D deficiency. COVID-19 symptomatology varies from mostly asymptomatic, to, up to 2% fatality. The latter is characterized by cytokine storm, an immune reaction, diffuse arterial thromboembolism, acute respiratory distress syndrome, pulmonary oedema, and death. Vitamin D deficiency positively corelates with ...