Antibiotics cannot kill viruses because viruses have different structures and replicate in a different way than bacteria.Antibiotics are produced by microorganisms to kill or control the growth of other microorganisms by blocking specific metabolic pathways within the cell.Viruses do not carry out many metabolic processes themselves. Instead they rely on a host cell (a human cell) to carry out these processes for them. Therefore viruses cannot be treated with antibiotics as it is impossible to kill the virus without harming the human cells,so we can say antibiotic can not kill viruses.