viral escape

Viral escape occurs when a virus changes its genetic makeup to avoid being detected or neutralized by the immune system. As our body’s defenses learn to recognize a virus, the virus can mutate, producing new versions that the immune system doesn’t recognize as easily. This allows the virus to continue infecting cells and spreading even after an immune response has started. It's similar to and a major reason for why some diseases, like influenza or COVID-19, require new vaccines over time—because the virus keeps evolving to "escape" our immune defenses.