National and international surveillance of antibiotic resistance 1

Hello, my name is David Livermore, I'm Professor of Medical Microbiology for the University of East Anglia in Norwich. I'm also Public Health England's lead on Antibiotic Resistance. And for 14 years, I headed Public Health England's National Reference Laboratory examining antibiotic resistant bacteria in the United Kingdom. What I want to do in this two-part presentation is to look at national and international surveillance of antibiotic resistance.

In this first part, I want to look at how data can be collected for surveillance of resistance. Why we seek to do surveillance, and some of the pitfalls and challenges with the data. In the second part, we'll look more at some of the data that have been collected and their interpretation, and how that can be used to assess the success or failure of interventions.

The reasons to do surveillance of resistance are really pretty obvious. Firstly, to identify changes in prevalence and trend, to detect new types of resistance as they emerge. Is the MRSA rate going up? Is it going down? Have we started to see something new appear? Resistance to Carbapenems in Gram-negative bacteria, for example, or new emerging Colistin resistance. Surveillance is also important to assess the coverage of empirical therapy. Now this always comes as a surprise to the non-medics, but usually you start treating an infection without knowing what the pathogen is. You've got a sick patient there. You've clinically diagnosed them as having urinary tract infection or being potentially septic. They need antibiotics now! Not after the two days or so that is going to take you to grow the bacteria into test which antibiotics are susceptible to. So, you need an idea of what are the most likely bacteria in urinary tract infections or sepsis or whatever and what the local prevalence of resistance is, so you can choose what antibiotics to give that patient upfront here and now before you've got the susceptibility results for the particular organism from the lab. Hopefully, after two days, once you do have those results, then you're going to be fine with the treatment. You'll step down from a broad spectrum antibiotic, one that's covering all the likely types of pathogen locally in that clinical setting, to something narrow spectrum that's tailored against the particular bug that's been growing from the patient. Lastly, we need surveillance to assess the impact of interventions. We take steps, improvements in infection control, better hand hygiene, whatever to try to combat our problems, well, let's say MRSA or Clostridium difficile. We need surveillance to know if our interventions have succeeded or if they failed.