Viruses are different from bacteria, they have a different structure and a different way of surviving. They also don’t have cell walls that can be attacked by antibiotics, instead, viruses are surrounded by a protective protein coat. Viruses actually digress into, live in, and make new copies of themselves within a host cell. They can't reproduce on their own, as bacteria do, Instead, they attach themselves to healthy cells and reprogram those cells to make new viruses. It is because of these reasons antibiotics are not effective on viruses.