Delta and Omicron both are mutant variants of the original strain of the COVID-19, which originated in China in 2019. Delta was first identified in India in 2020 and later it led to the second wave of the coronavirus in the country claiming millions of lives, while cases of omicron variant were first reported from South Africa. The symptoms of both variants are different from each other. Experts reveal that fatigue, joint pain, cold and headaches are four common signs of omicron that are different from that of the Delta variant. Apart from these, loss of smell and taste, which were common signs of Delta were hardly seen in the case of the Omicron.