Animal & Veterinary
NARMS Overview by Beth Karp, DVM, MPH, DACVPM
DR. KARP: Good morning, everyone. Today you’re going to hear presentations about antimicrobial resistance monitoring programs in different parts of the world beginning with the NARMS program here in the United States. So I thought I would start this session by reviewing why it’s so important to have resistance monitoring programs.
Okay. First of all, resistance monitoring programs allow us to determine, to look at trends over time in resistance. They also help us, to allow us to detect emergence of particular resistance patterns. They also help us to assess risks to both human and animal health. They provide a basis for policy recommendations. They also help us identify the need for potential interventions. And also help us assess the impact of different interventions. They also guide the design of research studies as well as prescribing practices and prudent use recommendations.
NARMS is the National Antimicrobial Resistance Monitoring System for Enteric Bacteria. And it is a public health surveillance system. And it tracks changes in the susceptibility of enteric bacteria to antimicrobial agents of human and veterinary medical importance. And it is a collaboration between FDA, CDC, USDA and participating health departments.
NARMS has three components. And you can see here, there’s the human component, the retail meat component and an animal component.
The program began with the human component in 1996 and health departments throughout the United States submit clinical isolates to CDC here in Atlanta and CDC conducts the susceptibility testing in their NARMS laboratory.
Currently there are 54 health departments that participate in NARMS. It’s all state health departments as well as four local health departments.
The animal component of NARMS began the following year in 1997 and it is housed within USDA’s Agriculture Research Service. And the isolates, actually the isolates and samples come from USDA’s Food Safety Inspection Service. And the isolates are sent to USDA ARS NARMS’ laboratory in Athens, in Athens, Georgia.
The retail meat component of NARMS is the most recent addition to the program and it began in 2002. And currently ten sites that participate in FoodNet as well as Pennsylvania participate in the program. Each of those sites purchase retail meat samples every month. And they culture the meat samples for certain bacteria. And those isolates that they have are sent to FDA’s Center for Veterinary Medicine Laboratory in Laurel, Maryland for testing.
So the NARMS program has significantly expanded over time. And this slide shows the different bacteria tested within NARMS, and the human component, the animal component and the retail meat component.
As I mentioned the NARMS program began in 1996 at CDC. And the bacteria that were tested then included -- I’m sorry, I keep advancing the slides here -- began with non-typhi Salmonella, E. coli 0157:H7. And then the following year Campylobacter was added in 1997. And then in 1999 both S. typhi and Shigella were added.
The animal component began with testing of Salmonella in 1997. 1998 Campylobacter was added to the program. And then subsequently both E. coli and Enterococcus were added.
The retail meat program began, again in 2002. And all sites test for non-typhi Salmonella and Campylobacter and some of the sites tests for Enterococcus and E. coli.
So, I think we can skip over this slide since Doctor McDermott already went over the objectives of NARMS.
This slide shows the different reports, the annual reports that come out from each agency. So each NARMS agency publishes its own NARMS report. So the human component CDC publishes Human Isolates Report every year. FDA publishes a Retail Meat Annual Report, and USDA publishes the Animal Isolates Report.
And you can find each of the reports on the agency website. If you go to the main web page and just type in NARMS in the search box you’ll easily find them. And there are also, if you’re on one of the sites, you will also find links to the other NARMS sites as well.
So in addition to the individual agency reports, there are also NARMS Executive Reports. And these are -- FDA coordinates the publication of these reports and what’s different about these reports is that they include data from all three components of NARMS. And there are reports published for 2003 through 2007.
And these repots have data side-by-side from the three components. So I have a couple of screen shots showing some samples of tables from the Executive Report. You can see here the human -- this is a slide here that shows the most common serotypes among non-typhoidal Salmonella isolates in 2007. And you can see that the serotypes from humans are shown here, retail meats and then food animals.
And you can see, for example, here you have the chicken breast isolates right next to the chicken isolates, ground turkey, and next to the turkey is -- below you would find the ground beef, cattle, and then pork chops and swine isolates. So you can see it, you can easily compare data across the there components of NARMS.
Here’s another example from a table from the Executive Report and this one shows resistance among all non-typhoidal Salmonella by year. And the top of the table shows the number of isolates tested by year for each source. And you can see the human isolates were listed first, the retail meats and then the animal isolates. And then below in this area is the resistance data.
So, by year you have the resistance percent as well as the number of isolates for human, the retail meats and then the food animals.
One other thing that we’ve been exploring in NARMS is the use of interactive data -- interactive graphs to show NARMS data. And these -- USDA has done quite a bit of work on this. And the slides that I’m going to show you were courtesy of Avita Harrow at USDA ARS.
So, we currently have two graphs that are posted in conjunction, they’re a supplement to the Executive NARMS Executive Reports, so they’re posted on the FDA website. And this is the Salmonella graph. And over here on the left you see the different antimicrobials. So you first select the antimicrobial class that you’re interested in. And then you can select the antimicrobial agent.
And then over here on the right, you can select the source that you’re interested in. So for example, if you want to see the human data, just click on the humans, chicken breast, chickens.
So, we think this will be a useful tool for people to explore the data visually. And we hope to have more of these graphs in the future. But right now we have the two graphs, we have this one -- I may have to exit the presentation to get to the next one.
So the other graph that we have is the Campylobacter graph. And this is very similar. You can select, which look at Macrolides, Lincosamides -- the main difference with this one is that you can select the species that you’re interested in looking at. So this is C. jejuni, so you can click on humans. And then if you wanted to for example add E. coli you see the difference as you change the species.
So, we currently have these two graphs posted and you can also go to USDA’s website, they have actually more graphs, more interactive graphs. They have graphs that show resistance by serotype as well as MIC distributions. And hopefully we’ll be having those -- also for -- for the Executive Reports, with data from all three components of NARMS.
So, I wanted to just mention research and this is -- some of these studies have already been mentioned, but NARMS is very, as you heard, very involved in research in different projects, different areas.
And these two slides that I’m going to show you just have a few of the projects that NARMS scientists have been working on.
So, major areas are methods development and CVM developed a broad micro-delusion method for Campylobacter. There has also been rapid isolate testing. For example, PCR to detect specific genes as well as microarrays to look at multiple genes at one time. Molecular serotying. CDC, the NARMS lab has collaborated with the National Campylobacter Reference Lab to test real time PCR. Real time PCR method to speciate Campylobacter. There has also been use of MLST, Multi Locus Sequence Typing for Campylobacter.
So, in addition to this there also have been pilot projects to examine emerging issues. And currently the retail meat sites in NARMS are testing meats for MRSA, VRE, and also C. difficile in retail meats.
Other pilot projects have included looking at Salmonella, E. coli and Enterococcus in animal feeds. Also comparing Enterococcus strains from humans and retail meats and also use of MLST for Enterococcus.
Other studies have been done to help understand the emergence and spread of resistance. For example there is a project, to link NARMS susceptibility data with PFGE results, to see which resistant clones are spreading. There has also been -- historical strains have been tested to try to determine when exactly resistance emerged in those bacteria.
There has also been a lot of research on different mechanisms of resistance. For example looking at Quinolone resistance and also resistance to extended-spectrum cephalosporins.
There has also been research looking at virulence genes and virulence factors, for example in Salmonella Kentucky, Salmonella Kentucky is a serotype that is very common in chickens, but is rarely found to be a cause of human illness.
There has also been research to -- in a development of resistance in animals that are treated with the antimicrobials.
In addition to -- these studies have also been epidemiological studies looking at risk factors for acquiring resistant infections, and also studies to look at clinical outcomes of resistant infections.
So, I just wanted to conclude with a few words on international activities and several of our speakers have already mentioned some of the activities. And as Dave White mentioned, foodborne disease and antimicrobial resistance are global problems. There is increasing international travel and trade, which means that people, foods and animals are moving routinely around the world. This was a big theme in the ICEID Conference that took place here this week. So international activities are really critical.
And as Dave mentioned there is a need for, to harmonize -- for international harmonization to help facilitate comparability of data but also -- also international cooperation is needed to limit this spread of resistance.
And these are just a few of the NARMS international activities. And Dave White already mentioned some of these, the GFN and you’ll hear more about that this afternoon, PulseNet International, the NARMS scientists service advisors and trainers for both of these programs. ResistVet, which is an integrated food chain surveillance project in Mexico. FDA provides support for that. And NARMS laboratories also train scientists in their laboratories.
There are also collaborations with other antimicrobial resistance programs including CIPARS in Canada, the Canadian Integrated Program for Antimicrobial Resistance Surveillance. DANMAP in Denmark, and also AGISAR as was also mentioned. And you’ll hear about that later. And also as Dave mentioned, NARMS scientists serve on the Codex Task Force on Antimicrobial Resistance.
So, you’ll hear more about the research activities, more details about some of those research activities that I mentioned and also international activities, research tomorrow and this afternoon, you will hear all about the international programs. So, thank you very much.
DR. GREEN: Thanks, Beth. Our next speaker is Doctor Ezra Barzilay. And he will be speaking on surveillance of antimicrobial resistance in humans. Doctor Barzilay is currently the lead of the National Surveillance Team in NARMS, in the Enteric Diseases Epidemiology Branch at CDC. He is a former EIS officer. And his field experience includes international public health interventions, foodborne outbreak investigations and serving as a trainer and expert consultant for the World Health Organization.