That’s reflected in the fact that viruses are impervious to antibiotics—chemicals valued for their ability to kill bacteria (which are cells) or at least impede their growth. Penicillin works by preventing bacteria from building their cell walls. So do its synthetic alternatives, such as amoxicillin. Tetracycline works by interfering with the internal metabolic processes by which bacteria manufacture new proteins for cell growth and replication. Viruses, lacking cell walls, lacking internal metabolic processes, are oblivious to the effects of such killer drugs.
