What term describes changes that occur in a virus’s genome?

The term that describes changes occurring in a virus’s genome is viral mutation. Viral mutations can arise due to various factors, such as errors that occur during the replication of the viral genome, which can lead to alterations in the sequence of nucleotides. These mutations can have significant implications, influencing the virus's virulence, transmissibility, and resistance to antiviral treatments.

Viral transmission refers to the process through which a virus spreads from one host to another, which does not directly involve changes in the viral genome itself. Genetic screening is a technique used to analyze genetic information, typically for identifying genetic disorders, rather than addressing changes in viral genomes. Gene therapy involves the alteration of genes in a person’s cells to treat or prevent disease, which is distinct from the natural or induced changes occurring in a virus's genetic material. Thus, viral mutation specifically captures the essence of genetic alterations within a virus's genome.