What are the causes of antimicrobial drug resistance and can it be prevented? If not, how can we reduce the risk of development of local (eg, in hospitals) or global drug resistance?
Mark Loeb: There are several important factors. A very important factor, of course, is the use of antibiotics, inappropriate prescribing of antibiotics in the community and in hospitals. That certainly drives antibiotic resistance. An important factor is the organisms, the bacteria themselves and their rate of mutations. Natural selection occurs and when there is variability in the bacteria, there is a chance for more spread.
The other thing is clonal spread. You can induce resistance, but clonal spread is through infection control, in hospitals, for example, and in the community.
The other thing that sometimes is not paid as much attention to is use of antibiotics in animal feeds. All of those are important factors for antimicrobial resistance.
I would say yes, the spread probably cannot be eliminated because antibiotic resistance continues to get worse over time. It does not tend to get better. It does not tend to go back. It tends to get worse all the time. The spread could be reduced, though, by optimizing antibiotic use, by being more prudent with what is fed to animals. I think that those are strategies to try to reduce the spread of antibiotic resistance or its development.