**4. Discussion**

The molecular mechanisms of viral replication, multiple animal reservoirs, and immunological selection methods have the possibility for viral evolution to immune escape variants (**Figure 1**). Such epidemiological and evolutionary mechanisms are already seen in the emergence of different VOC worldwide [44].

### **Figure 1.**

*Biological determinants of emergence of SARS-CoV-2 variants. An infection of SARS-CoV-2 in humans results in viral replication. In born errors of viral replication or genomic recombination can result in viral mutations. People with natural/artificial immunity will neutralize the non-mutated virus but has non-neutralizing immune response against mutated variant. Mutated SARS-CoV-2 thus undergoes this immunological selection for emergence of SARS-CoV-2 variant. Infection in animals with different host cell machinery led to mutated SARS-CoV-2 with potential for species jump and spillover into humans and emergence of SARS-CoV-2 variant.*
