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U.S. Department of Health and Human Services

Animal & Veterinary

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Questions and Answers Session

DR. McDERMOTT: I have a question for Lucie if she is here still. Oh there you are. When the use went down for ceftiofur and you said they resorted to other compounds, did you have enough information on those to know how much and did you see any say gent resistant or anything else come up in its place?

DR. LINDSEY: The answer is we don’t have, you know, very good information apart from anecdotal information. We do talk with the vets and in the province of Quebec at least, they are relatively transparent in what they are doing.

So we know that Linco-spectin was mainly what they were using. Sometimes gentamicin, but they can’t use gentamicin that much because the chickens are usually ready by 33 or 35 days of age which is shorter than the withdrawal period for gentamicin.

One thing that they were telling us was that when they stopped the use of ceftiofur -- because they do monitoring of their own E. coli as well at the hatchery level. When they stopped ceftiofur use, they saw an emergence of gentamicin resistant strains in their collection which is not huge, but we tend to see the same thing without gentamicin use.

So it is just like when they stopped the ceftiofur, the other strains that were there reemerged. So that is the one thing that they have been communicating to us. They do use gentamicin once in a while, but I don’t think they are able to use it to the same extent they are able to use ceftiofur. But hopefully we will get some quantitative information in a few years from them and the rest of Canada.

So I don’t know, is that answering?

DR. WHICHARD: Jean Whichard, CDC. I just wanted to thank all the speakers this morning for great presentations. If I had to characterize this morning’s session, it would be partnerships and value-added and really taking the NARMS surveillance a step further in terms of research and partnerships with PulseNet, VetNet, with Canada with their use studies and such that came along with.

I would just like to point out Dr. Collette Fitzgerald, she has really got her finger on the pulse of all things with Campylobacter phylogenetics and this is a huge opportunity for us as a program to understand the persistence of ciprofloxacin resistance. You know, she is doing capacity building in the states as well. So I just really appreciate that presentation especially and the work that she and Patrick Kwan are doing.

DR. SILLEY: Peter Silley, MB Consult, a question for Heather Green. I really enjoyed your presentation. If I understood correctly, the human side, you would take in all the human data together. Would your conclusions have been any different if you had restricted the isolates just from the same ten sites as the retail meat isolates had come from?

DR. GREEN: That is actually a good suggestion. I am trying to remember why we did not do that. I don’t believe -– well initially – the data that we got from PulseNet was actually very limited and we did not have state-specific data. So we were only able to get aggregate data from the PulseNet database team. But that is something that we might actually be able to look at now. I think initially we were talking different languages so they kind of didn’t know what we wanted and we didn’t –- yeah, they didn’t know what we wanted. Also, they didn’t have time to do the detailed analysis of pulling out state by state data. But that is something that we could look into.

DR. WHICHARD: Jean Whichard, CDC. I would just like to follow up on that. Does limiting that analysis then assume that those retail products are only distributed in that state where the human infections are? Because I think we know that, you know, meat can be distributed throughout the country, so I don’t know that limiting it to, you know, comparing the human and the retail –- I am getting the nod from Amy Krueger so maybe that is something to add here.

DR. KATHARIOU: Sophia Kathariou from North Carolina State University. I have a question for Dr. Lindsey. There was a mention of mercury resistance genes in these plasmids which I find really interesting and I want to know whether perhaps the strains had been screened for resistance to mercury and also whether other detoxification systems? Because I remember there was a study some years back from Germany with Inc A/C plasmids from human wastewater treatment plant and there were genes there for detoxification of toxic dyes of triphenylmethane dyes. I don’t know if Dr. Lindsey is still here.

DR. LINDSEY: No, we did not do any screening for mercury and that is a good point and that is something that we should look at. I would love to talk to you about that further if you have any suggestions, but I am just working on the analysis and writing the paper so I will look at that further. So thank you.

DR. ZHAO: Rebecca, I have another question for you. For your multiarray hybridization, did you use, you know, PCR for validating your hybridization results to validate your hybridization? Because we have found many cases of false positive and I was just wondering.

DR. LINDSEY: I did not us PCR to validate, but I wrote a manuscript, I wrote a paper on that. It has been published. I used a number of control samples that had been sequenced that I knew were positives and negatives should be and that is how I validated it. As I mentioned, that has been published. I published a paper on the plasmid part of it and then Dr. Frye published a paper on the AR probes as well.

DR. ZHAO. Okay. Did you find any –- you said that you have not found any beta-lactamase gene beside the CMY? Did you find any like a TM –- you know, in all cases with retail meat we found about 47 percent of the ampicillin resistant Salmonella contain TM. I am just curious, did you find any other beta-lactams beside the CMY?

DR. LINDSEY: Well we -– the microarray did not have very many beta-lactamase genes on it. It only had what would have been present in the Inc A/C plasmids or the HI1 which would be the CMY-2 and I think it was the SHV. So we were not looking for them at that point. In the sequencing, some of these other beta-lactamase genes should come out and we will know at that point when I get to analyze that data.

DR. ZHAO: Okay, thank you.

DR. CARATTOLI: I have a question for Rebecca. Alessandra Carattoli, Rome, Italy. Have you noted if by sequencing this plasmid it is confirmed that they have lost the self-servability (sic). This is a data that is coming our now that the acquisition of CMY-2 destroyed the capacity of this plasmid to be self –- to model self conjugation. It seems that they are entranced by coursing* the plasmid. This is amazing because the success they had, the distribution they had could be associated with the capacity to self-conjugate. Why the sequence analysis that is coming out now seems to demonstrate that in fact it is not like this. So you have a group of plasmids that have lost an entire Tra (sic) if I have understood, Tra locus and can you confirm this tendency on this plasmid to be not self-conjugative?

DR. LINDSEY: Well there were just a few type four conjugation genes which were missing on the microarray, not a lot and not a whole section by any means. So I have just gotten the sequence so it is just all “A’s”, “T’s”, “C’s”, and “G’s” and I really have not gotten any further than blasting that so that is something that I would definitely want to look at or collaborate with somebody on that aspect of that.

So if you are interested or know anybody, yeah, I would love to talk to you more about that.

DR. KOTARSKI: Sue Kotarski, Pfizer Animal Health. I wanted to compliment the CIPARS group and Dr. Dutil on the comprehensive examination of the Heidelberg. I would like to ask a question about the serotypes that you are seeing in among the broilers because the slide that you gave discussing the cephalosporin resistance in broilers, it was striking to see there was -- you mentioned the Kentucky being the cephalosporin resistance. And like your comments about cephalosporin resistance in Heidelberg, though there were really few broilers in that dataset. Could you comment please?

DR. DUTIL: I am not sure if I --

DR. KOTARSKI: Well you are seeing cephalosporin-resistant Heidelberg in the retail chicken. My question is, are you seeing cephalosporin –- oh I am sure you are seeing cephalosporin resistant in Heidelberg in the broilers themselves rather than in retail meat?

DR. DUTIL: Yeah, yeah. We are seeing it. We don’t have farm but we have the abattoir and the abattoir collection that we have comes from fecal samples. We do see the same thing. I took the abattoir slide out of it because I wanted to stick with the time I had. But we see the same thing.

However, the national data that we have is that –- the abattoir data that we have is at the national level, so what we have is not just for Quebec. When we take out just the data from Quebec, we don’t have a lot of discrimination because there are not a lot of isolates, but we tend to see exactly the same thing and it disappeared totally at the end of the withdrawal in the abattoir data as it did in the retail data.

What is surprising is that we have this –- that we see it at the retail data because there are exchanges between provinces. However, Quebec is a big producer of chicken and also of eggs and it is sending, shipping day-old chick outside the province more than they are importing.

There is a quota system in Canada as well so there is not, in chicken at least. There is some kind of clustering of the production and the retail meat, although it is not 100 percent. So to answer your question, yes we do see it not in farm but in fecal samples so it is really close to it. When we look at the data that comes from other research, they confirm the same thing that we have found. So, yeah, it is also seen at the farm level, not just in retail.

DR. KARLSSON: Thank you everyone. It is time to break now for coffee and I think that we will try to stick to the time schedule and meet at 9:40 again. Thank you.

(Whereupon a brief recess was taken)