Emergence of SARS-CoV-2 New Variants and Their Clinical Significance.

COVID-19 is a respiration-related disease caused by SARS-CoV-2 and was identified in China's Wuhan city. More than 223 countries are affected by the disease worldwide. The new variants of the COVID-19 virus are causing problems, from average to life-threatening pneumonia and acute respiratory distress syndrome (ARDS). Presently, there are 170 vaccine candidates, out of which 10 have been approved by the WHO for vaccination, such as Ad26.COV2.S, Pfizer/BioNTech, COVISHIELD, Covovax, Moderna, KoviVac, and some other vaccines to combat the deadly SARS-CoV-2 infection. From all these vaccines, Pfizer/BioNTech and Moderna are showing the highest efficacy against COVID-19. These vaccines are highly efficient against COVID-19 disease, but their potentiality against new variants remains a question. COVID-19 vaccines are highly effective at preventing severe illnesses, hospitalizations, and death. The antibodies elicited by earlier infection or vaccination are the key for possible protection against SARS-CoV-2. The problem has been exacerbated by new information from Africa on the origins of the novel contagious SARS-CoV-2 strain. These new strains occur due to unique mutations in the spike protein, which modify SARS-CoV-2 transmission and infection capabilities, limiting the efficacy of the COVID-19 vaccination. Hence, there is a need to find a potential vaccine against it.