Antibiotic Conservation: Use Less Often When Unnecessary and Higher Amounts When Needed

Development of resistance progresses through three stages. First, resistant mutants are created in a pathogen population by mutation and by horizontal movement of resistance genes from other microbes and viruses. At present, we can do little about either of these natural processes. The second step is gradual enrichment and amplification of the small number of resistant mutants in the pathogen population. This is the step that must be blocked if we are to control resistance. The third stage, discussed in Chapter 7, “Transmission of Resistant Disease,” is the dissemination of resistant strains. This is where we currently put most of our effort. Unfortunately, controlling the spread of resistant outbreaks is largely a holding action. We must also focus on stopping the emergence of resistance.