Effect of viral, reservoir, host, and environmental factors on viral evolution that affect morbidity and mortality of COVID-19 disease

Abstract

The COVID-19 pandemic has been going on for more than 2 years. The number of patients with the disease continues to increase as well as those who die. The number of cases of illness and death is different in each country and even varies in one country in certain seasons and in certain ethnic groups. This virus also always creates new variants that have different virulence, so that it can prevent the transmission of the COVID-19 virus. Virus evolution triggers the emergence of new virus strains and these new variants cause different morbidity and mortality. Other factors thought to support the evolution of the virus are reservoir, host immunity, extreme environmental conditions. This is supported by the different percentages of morbidity and mortality in different countries. This study aims to determine the effect of the factors that influence the level of morbidity and mortality in terms of virus, reservoir, host, and environmental aspects.