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Transcript: USDA and CDC Update to Media on Highly Pathogenic H5N2 Avian Influenza Outbreaks

Moderator: Rodney Bain

April 22, 2015

11:00 am EDT

Coordinator: Good day and welcome to today's live broadcast from the USDA Radio Studios in Washington D.C. featuring USDA's Chief Veterinary Officer, Dr. John Clifford, as well as Dr. Alicia Fry of the Centers for Disease Control, and Dr. David Swayne of the Southeast Poultry Research Laboratory also with USDA.

Reporters and members of the media wishing to ask a question of our guests after the opening remarks, you can do so, please press star 1 on your telephone touchtone pad. It's now my pleasure to introduce USDA's Chief Veterinary Officer, Dr. John Clifford.

Dr. John Clifford: Thank you very much. And thanks everyone for being on the call today. As you all know we've been dealing with the Avian Influenza, Highly Pathogenic AI. And we refer to it as High Path AI because frankly it kills turkeys and chickens.

So one of the things we'd like to tell you all today is that we've had very good success in being able to address these things once we've been able to find and locate these outbreak situations. So that we've been able to contain a lateral spread from these types of locations as well.

One of the challenging things that we have is though because of the contamination - environmental contamination of this virus from wild water fowl it presents a lot of unique challenges to us with regard to this. But the U.S. has one of the best in the world surveillance systems for High Path AI and for Low Path AI for that matter. And as a result we've been able to get very good cooperation from the states and the industry to be able to find these locations very quickly and be able to respond.

And I would definitely as a part of this wanted to thank all the support that we've gotten from our state animal health officials, as well as from the poultry industry and producers themselves. I know this can be very devastating to them but they've been very cooperative and it's been a good relationship together.

And I also wanted to thank the support we've gotten from our guests here today as well; from Dr. Alicia Fry and the work of CDC with this, as well as Dr. David Swayne who is the Director of the USDA's Southeastern Poultry Lab.

So with that I'd like to next turn it over to Dr. Alicia Fry to make some opening comments.

Dr. Alicia Fry: Good morning. Thank you for having me on today to discuss the human health implications of current domestic outbreaks of Highly Pathogenic H5 viruses in U.S. birds and poultry.

First let me start by saying that the Avian H5 viruses that have been found in U.S. wild birds and commercial poultry are different from the ones that we've been following around the world for several years now. These specific viruses have not caused infections in people anywhere in the world. CDC considers that the risk to the general public from these outbreaks to be low at this time.

That said, human infections with similar avian influenza viruses have occurred and it is possible that we may see human infections with the viruses associated with recent U.S. bird flu outbreaks. Most human infections with avian influenza viruses have occurred in people with direct or close and prolonged contact with infected birds.

While we are cautiously optimistic that there will not be human cases, we must be prepared for that possibility and we are taking routine preparedness steps, including studying these viruses further and creating candidate vaccine viruses which could be used to make a vaccine for people if one were needed. Again, these are routine public health preparedness measures.

So far genetic analysis has not shown any of the markers that are known to be associated with increased severity of illness in people or an increased ability to be spread to people or spread among people -- and that's good news. But preparedness and protecting public health is our continued goal.

CDC is working closely with state and local health departments and our colleagues at USDA to minimize public health risk from these bird flu outbreaks. People in contact with known infected or possibly infected birds should take precautions to protect against infection. USDA has excellent public education resources on their Web site for poultry workers, hunters and bird enthusiasts.

For the general public; avoid wild birds and observe them only from a distance, avoid contact with domestic birds or poultry that appear ill or have died, and avoid contact with surfaces that appear to be contaminated with feces from wild or domestic birds. CDC has issued public health guidance for High Path AI H5 testing and preventative medication of people exposed to these viruses.

People who have had contact with infected birds should monitor their own health for possible symptoms, for example flu-like symptoms or conjunctivitis. People who have had contact with infected birds may also be given influenza antiviral drugs preventatively.

CDC has put up a Web site with information on Avian Influenza and with links to all our domestic H5 guidance documents. We are monitoring the situation closely. This is an evolving public health situation and information may change as time goes on and we will provide updated information as it becomes available.

The address for the CDC Web site is And questions from the public can be directed to 800-CDC-INFO or 800-232-4636. Thank you.

Dr. John Clifford: Thank you Dr. Fry. And now I'd like to turn it to Dr. David Swayne to make some opening comments. David?

Dr. David Swayne: Thank you Dr. Clifford. I represent the Southeast Poultry Research Lab which is USDA's agricultural research service in-house lab that conducts research on Avian Influenza. And we provide this research support not only to USDA APHIS, the regulatory agency for Disease Control, but also we provide research data to the states that may be affected, as well as the U.S. poultry industries.

Currently our research has been focused on developing specific molecular tests to detect this new strain of H5 High Path Avian Influenza. And we have made our test development and validation, have transferred that to our national Vet Services laboratories and on to the State Laboratory Diagnostic Network System. Now we've also developed a molecular test to detect the innate type of the virus, and that also has been transferred.

We have several ongoing studies that examine the different outbreak viruses to determine how they are transmitted from bird to bird, as well as which species of poultry, or potentially wild birds, can be affected by these viruses and what the potential outcomes are.

We also have, as part of our research portfolio, vaccine development which is a routine process for us. Now this type of research we do with all High Path AI viruses from around the world, which is part of our mandate, not only as a USDA lab, but also as a world organization for animal health collaborating center on research for emerging avian diseases.

Now I'll pass it back to you Dr. Clifford.

Dr. John Clifford: Thank you Dr. Swayne.

Coordinator: And thank you. And we are open for questions, so reporters and members of the media this reminder, if you do have a question for any of our guests, Dr. John Clifford, USDA's Chief Veterinary Officer, Dr. Alicia Fry from the Centers for Disease Control, or Dr. David Swayne of USDA's Southeast Poultry Research Lab, then press star 1 on your telephone touchtone pad.

And we will go to the phone lines. Our first call today belongs to Blake McCoy of KARE. Blake, good day.

Blake McCoy: Hi. I understand the USDA is working on a potential vaccine for this current strain of the virus. Where does that stand?

Dr. John Clifford: I think, Dr. Swayne do you want to respond to that please?

Dr. David Swayne: Yes. I mean our laboratory, which does the original vaccine development work, we are working on a potential vaccine strain that can be used as an inactivated vaccine. And we're making progress on that. It's a multi-step process that involves completion of one step, evaluating the information, then going back to additional steps.

So at this point we have a potential seed strain. But once we complete our work, which will include testing in chickens and turkeys, the decision to use that vaccine will only be made if it's necessary in the regulatory process of the eradication.

So our work is only on the front end just to say, "Do we have available tools like vaccines to be used," but the process of using vaccines will only be decided by the Animal Plant Health Inspection Service in consultation with the state labs.

Coordinator: We now go back to the phone lines. Our next call belongs to P.J. Huffstutter of Reuters News. P.J., good morning.

P.J. Huffstutter: Hi, good morning. This message is actually for Dr. Fry. I just had a quick question with regards to the scale of the outbreak. Is the - given that the outbreak has definitely been spreading at this point, is there any indication that we may be more likely to see the potential for a human infection just because there's been the potential for more people exposed to the virus or no?

Dr. Alicia Fry: Well right now from everything we know it seems like the risk for human infection is very low. But you're right, we're really at the beginning of this and so we're monitoring very closely. And we're cautiously optimistic that we will not see any human cases, but there certainly is a possibility that we may.

Coordinator: USDA's Chief Veterinary Officer is with us here in the USDA Radio Studios, joining us on the phone lines Dr. Alicia Fry of the Centers of Disease Control and Dr. David Swayne of the Southeast Poultry Research Lab, and of course you in the listening audience. And reporters and members of the media, if you have a question for any of our guests please press star 1 on your telephone touchtone pad.

We go back to the phone lines. Our next call belongs to Steve Karnowski of the Associated Press. Steve, good morning.

Steve Karnowski: Good morning. Yes, this is for Dr. Fry. You had talked a little bit, and did I understand you correctly that as a precaution you have begun some preliminary work in case it becomes necessary to develop a human vaccine for this. Could you elaborate on that?

Dr. Alicia Fry: Well this is something that we do with any new influenza virus; we actually prepare seed vaccine viruses. We look for candidate vaccine viruses. We haven't made any - we haven't decided if we need to move to the next step. But for every new virus we actually pull it into CDC and we start to create candidate vaccine viruses.

We haven't gotten further than that at this point because we don't have a need to go further than that. But this is what we do. We have a large library of candidate vaccine viruses for different new avian influenza viruses that are detected around the world. And this is one of the reasons why we do surveillance so that we have these candidate viruses available.

Coordinator: Our next question belongs to (Mark Steele) of Minnesota Public Radio News. (Mark), good morning.

(Mark Steele): Good morning. I'm just wondering, on the USDA Web site the last test that showed the virus in a wild bird was over a month ago and I'm just wondering what you make of that? Is that raising concern or possibly any alternate theories on how the disease is being spread?

Dr. John Clifford: This is Dr. Clifford. Basically it doesn't really concern us from the standpoint of just finding the virus in a wild bird a month ago. We know that the virus exists in the wild bird population, the wild water fowl. So I think you still have to be very diligent in your biosecurity and making sure that you have the possibility of having virus contamination within the environment. And you take all those precautions based on that.

As far as the way the virus is getting into the facilities itself, we're looking at a multitude of possibilities with regard to that. We know that we've had very good biosecurity in the past to prevent introductions of High Path AI into our poultry operations but we're reviewing all of those. And as we review them, I know that the industry, if we find gaps, the industry is taking those very, very seriously and implementing new ways to address those gaps as soon as possible.

Coordinator: And again, a reminder to reporters and members of the media, if you have a question for any of our guests, Dr. John Clifford, USDA's Chief Veterinary Officer, Dr. Alicia Fry from the Centers of Disease Control, and Dr. David Swayne, USDA's Southeast Poultry Lab - Research Lab, then please press star 1 on your telephone touchtone pad.

And back to the phone lines we go. Our next call belongs to Brian Allmer of Barn Media. Brian, good morning.

Brian Allmer: Good morning. My question in regards to this avian influenza is, "Could you talk about some of the symptoms?" Because a lot of folks don't have large poultry operations, but they have backyard flocks maybe. Could you tell them what to look for in case they have it show up in their area?

Dr. John Clifford: Basically with the turkeys that we've been seeing, the turkeys will go off water and feed. And once they start doing that it doesn't take very long for the birds, you're talking hours at times for the birds to become very lethargic. And they'll have a condition that you might see that we refer to as torticollis, which is like stargazing and a little twisting of the neck, followed pretty rapidly by death. So these birds don't live a very long time.

In the chickens, you know you could see, especially the layers, you could see a drop in egg production and some of the same symptoms of going off feed and being lethargic prior to death. We're not seeing a lot of respiratory signs actually within the turkeys themselves.

Coordinator: Before we go to the - back to the phone lines a question for you John, and actually for David too as well, biosecurity has been one of the messages that had been promoted in the industry, and there's also - there's commercial and there's the backyard flock. So maybe give us I guess the quick summary as far as biosecurity measures and what is similar, what is different, between commercial flocks and backyard flocks in that regard.

Dr. John Clifford: Well with regard to biosecurity, any kind of biosecurity with commercial operations, it means that you need to keep vehicles going in and out of the property. They need to be cleaned and disinfected. I'm talking about the tires of the vehicle and other components as well. Any equipment entering or leaving a facility needs to be cleaned and disinfected. Even if it's moving from house to house it needs to be cleaned and disinfected.

Every worker on that farm or location needs to have clean footwear when they enter and clean their hands, disinfect their hands when entering every single house on that facility. And so basically you're looking at the possibility of outdoor contamination in any of these facilities that are very closely located to lakes where there's a large population of wild water fowl.

With the backyard birds it certainly can be more difficult, but if you are near wild water fowl you need to keep those birds enclosed as best you can and keep them away from the wild water fowl, otherwise they're going to be at considerable risk for introduction. And that includes individuals caring for those birds need to be very careful about making sure that they're not carrying the virus on their feet or hands into that facility.

Coordinator: David, any additional thoughts on biosecurity measures.

Dr. David Swayne: Just one additional thing about the backyard flocks is of course the water source used to water those backyard birds. It should not be surface water, so for ponds or lakes where the wild birds might be, but it should be a water source that is a municipal water source. That way you know that for sure it does not have the virus. And that would be a fresh, clean source of water for those back yard birds.

Coordinator: Back to the phone lines we go. Our next question belongs to Bob Ruth of CIDRAP News. Bob, good morning.

Bob Ruth: Good morning, thanks for taking my question. I've heard that USDA is looking into the possibility that the virus might spread through the air somehow via airborne dust or whatever. I wonder if you can comment on that?

Dr. John Clifford: Yes, I can comment on that. Basically what we're talking about, this is you know, the AI influenza virus is not generally spread - it's not an aerosolized virus that spreads easily that way.

However, in the area that I was in Minnesota for example, and because of the close proximity some of these facilities are to lakes and large population of wild water fowl, the winds have been pretty high in places there. The day that I was there was 20 mile an hour winds and you could see a lot of dust blowing.

So what we're talking about is the wind carrying potentially like feathers or dust or things that could be a carrier of the virus and moving it into those houses. Some of those house - or most of the turkey houses will have a curtain on one side of the house that they can open and close to regulate the temperature within the House.

So we're talking about very short distances and high winds carrying dust and those types of particles that could potentially carry virus into the facility.

Coordinator: Reporters and members of the media, again this reminder, if you have a question for any of our guests please press star 1 on your telephone touchtone pad. Our guests include Dr. John Clifford, USDA's Chief Veterinary Officer, Dr. Alicia Fry from the Centers for Disease Control, and Dr. David Swayne from USDA's Southeast Poultry Research Lab.

And back to the phone lines we go with our next call. The question belongs to Megan Durisin of Bloomberg. Megan, good morning.

Megan Durisin: Morning. I just have a question relating to the weather. I've heard several times that once the weather warms up, you know, producers should start to see a relief and some drop-off in cases.

It seems that the cold spring temperatures here in the Midwest have been lingering on for some time. Is that seen kind of prolonging the reports of new cases we've been seeing here lately? And can you elaborate on what temperature we need to get to before we'll see a drop-off in new cases here in the U.S.?

Dr. John Clifford: I don't know if Dr. Swayne, you'd like to address that also, or even Dr. Fry. But we know that this virus doesn't like heat. So when it gets up to a certain level of temperature this virus doesn't survive easily, where it does like the cooler temperatures. And David, do you want to respond?

Dr. David Swayne: Yes, the other thing is that as we get into the spring and the summertime we also have a lot more sunshine. And with the sunshine comes ultraviolet light. And ultraviolet light will kill influenza virus.

So any virus that Dr. Clifford's mentioned before, that might be on dust that's in the air, that ultraviolet light is a very important way to kill that virus, or on individual surfaces.

So it's kind of hard to just predict a particular and say oh beyond this point, you know we'll have a drop off in cases because the virus is not surviving in the environment.

It's pretty complex. It involves the climate, the temperature itself, the amount of humidity there. So is it dry if it would get into, you know, the dryer part of the spring and the part of the summer.

Dryness also helps reduce the life of the virus in the environment, as well as the increase in temperature and the amount of ultraviolet that can fall upon surfaces and the dust particles in the air.

Rod Bain: And our next question today belongs to Kelsey Gee of the Wall Street Journal. Kelsey, good morning.

Kelsey Gee: Hey, good morning. Thanks for taking the time. So my question is, it's been reported that this virus could continue to spread beyond the migratory pathways that we've already identified it in, potentially moving toward the East Coast.

I'm wondering if you could say a little bit more about how that could happen and what you're forecasting for this fall.

Dr. John Clifford: Well you know from my perspective, I don't know if I'm forecasting anything for the fall. I would hope that we wouldn't see any more. However, because the fact that this virus has seemed to have adapted itself pretty well for the wild water fowl, and the fact that we've seen it already in three of the flyways, and including Ontario Canada now has had two cases which I guess there's some question whether it's in the Atlantic or Mississippi flyway.

But regardless, you know these birds, they don't just stay in one flyway. There's some crossover and mixing of these, especially in the northern part of the hemisphere here.

And so we would anticipate, if we see the virus again in the fall, that we're likely to see it all four flyways.

And I know Dr. Swayne has done a lot of work in this area, so David, you might want to also.

Dr. David Swayne: I think, just to emphasize what Dr. Clifford said, we can't really predict what's going to happen in the future. And we do have a concern and there is a concerted effort within USDA, USGS and other groups to continue to sample wild water fowl to try to track the virus.

But once the birds go in the summer up to their northern breeding grounds, it's really not sure if they will be able to bring the virus back south or not, or if the virus will burn out.

We have to prepare for that potential option, but we can't predict what will happen in the fall.

Rod Bain: The voice you just heard, Dr. David Swayne from the USDA's Southeast Poultry Research Lab. In the studio with us, Dr. John Clifford, USDA's chief Veterinary Officer, and Dr. Lisa Fry from the Centers for Disease Control.

And you on the phone lines, thank you for joining us. We go back to the phone lines for the next question and that belongs to Michelle Rook of WNAX Radio. Michelle, good morning.

Michelle Rook: Good morning Rod. Dr. Clifford I was wondering if you could update us on the export status now that Iowa has had the second case in a bird flock?

We had been hearing this morning that maybe Mexico was going to be banning eggs from the entire State of Iowa now.

Dr. John Clifford: So I have not seen a report yet on Mexico. I can tell you though that most of our trading partners, with some exception, have been, if we find cases at state levels, a number of those trading partners have been banning the state as a whole.

We do have some trading partners that recognize our zones that we put in place, which has been very effective. For example Canada has done that. We've been working very closely with Mexico to encourage them to follow the same process that we have with Canada, and we'll continue to work on that.

I think though as - if we continue to see more state involvement, you'll continue to see more restrictions placed on the U.S. by our trading partners, at least for the states that are affected

We've had some countries like for example South Korea and China that have cut off the entire U.S. from any movement of product or genetics out of the U.S.

Rod Bain: Mike Hughlett joins us now on the phone lines. He's with the Minneapolis Star Tribune and he will be asking the next question. Mike, good morning.

Mike Hughlett: Hi, this is for Dr. Fry. Dr. Fry I wanted just to make sure, essentially as the virus spreads and you see more cases among birds, I mean therefore you have a higher risk, although still a low risk to humans.

And also, do you have a number as to how many workers nationally have been, you know, potentially exposed; have been working in these bird farms? We have that number in Minnesota, but I'm looking for a national number.

And also, whether other states are monitoring these workers that have been possibly exposed.

Lisa Fry: Yes, thanks. Every state is monitoring the workers or any person who has been exposed in their state. And this is a rapidly evolving situation. I don't have exact numbers of how many people have been monitored, but I can tell you at this point, at least 100 have been monitored with no human cases.

And I'm sure over the next couple of weeks we'll be able to get a better handle on that number. But right now, I don't have a specific number for you.

Rod Bain: Again reporters and members of the media, if you have a question for any of our guests, please press star 1 on your telephone touchtone pad. We next go to Jeff Flock of Fox News Network. Jeff, good morning.

Jeff Flock: Yes, good morning, thanks. I presume that when you talk about lateral spread we're talking that there has been no case of any - of this spread via anything other than the wild water fowl. In other words, you don't have any evidence that one operation has contaminated another operation.

First of all hat's one question; is that the case. And second, on the method of depopulation, what method are you using to euthanize these birds, and does USDA monitor that?

Dr. John Clifford: So on spread, you know we continue to look at the issue of the potential for lateral spread. The epidemiology is still being done on a lot of the more recent cases. We've had a high volume of recent cases, so I don't want to say that there's been no lateral spread. And so it's something we're continuing to look at.

You've also - when you talk about lateral spread, you could have spread laterally within a farm itself where it spreads from one house to another house potentially.

So I was referring to lateral spread though earlier in previous discussions, up until the time before we've had this large number of cases in Minnesota, we had no evidence of lateral spread with the exception of one case in the State of Washington, very early on. But I cannot state that now because of that.

With regards to the issue of how we depopulate the birds, yes we actually contract. We don't do it ourselves. We contract with what we refer to as foaming crews that come in and use a foam based approach with regards to euthanasia for turkeys.

Now the - or any type of even poultry or chickens if they're on a floor type facility.

But in the case type facility we would be looking or working with the State of Iowa in looking at possibilities of C02 is also a possibility there because of the different type of structure that you have within that facility.

Rod Bain: Dr. John Clifford joining us in the studios. He's USDA's Chief Veterinary Office. Also with us this morning, Dr. Lisa Fry from the Centers for Disease Control, and Dr. David Swayne from USDA's Southeast Poultry Research Lab.

And you on the phone lines and in the listening audience, thank you for joining us. And we go back to the phone lines with the next question of the day. That belongs to Pam Fretwell of Farm Journal Media. Pam, good morning. Pam, are you there?

We'll go ahead and go to the next question and that belongs to Molly Samuel of WABE. Molly, good morning.

Molly Samuel: ...numbers - number of birds infected and number that are - that will be euthanized or projected numbers.

And I'm also wondering about surveillance in other states that are not yet affected. I'm in Georgia for instance, and this is something that you're preparing for here.

Dr. John Clifford: We have active surveillance on all of our commercial poultry flocks throughout the U.S. with regards to before birds are marketed and things. So that's carried out through a program we refer to as our National Poultry Improvement Plan.

As far as total number of birds; as far as depopulating, it's about -- and this is an estimate -- there's about 3.5 million birds that have been depopulated thus far. That would not include obviously, the new layer facility that's been identified in Iowa. So that's pretty much the numbers that I have to date.

Rod Bain: And back to the phone lines we go. Our next call belongs to (Betsey Jibden) of Farm Journal. (Betsey), good morning.

(Betsey Jibden): Good morning. I have a quick question. If USDA laboratories are working on a vaccine, what's being done on the private sector to create one? Could that speed up the process? And would USDA encourage these sort of vaccines if one is produced?

Dr. John Clifford: Dr. Swayne, do you want to respond?

Dr. David Swayne: I think that USDA is having discussions of how to go about a potential vaccine use. But I think right now the focus is in just preparation of, you know, can we have scientific information saying this vaccine will work or this vaccine will not work.

And so that really is - the preparatory work has to be made. And then the process, which is also under review is to look at how the number of outbreaks are occurring and that our primary role is detection and eradication by culling depopulation and surveillance.

And the decision to make a vaccine commercially and apply it in the field is something that's a little bit early, because there's a lot of information that has to be evaluated before that decision can be made.

And for us in the research side is we have to have that data available before the regulators can made an intelligent decision about whether a vaccine is appropriate or not. Dr. Clifford is that...

Dr. John Clifford: I would just like to add to what Dr. Swayne had indicated. We do know that there are several companies that we have had discussions with, with our Centers for Veterinary Biologics relative to this, and have an interest in looking at and developing possibly a vaccine for this.

Rod Bain: Back to the phone lines we go. Our next question of the day belongs to Donna Young of Scripps News. Donna, good morning.

Donna Young: Thank you. Thank you. This question is for Dr. Fry from CDC. Hi Dr. Fry. My question, if you could maybe explain a little bit of the difference of the variance of the H5N2 virus versus the H5N1, just so we have that on the record.

And then also if you could maybe explain a little bit, before you saw like the jump from the H5N1 to - from birds to humans, how long did that actually take before you actually started seeing that? Thank you.

Lisa Fry: Thanks. So when we - so when you say H5N1 I'm assuming you're talking about the H5N1 which has been reported from Asia and parts of Africa. And that H5N1 is distinct from the viruses that we are seeing here in the U.S.

So we have three viruses that all have an H5 but different Ns. One has an N2, one has an N8, and one has an N1. But it's different than the Asian H5N1s.

So at this point we don't know very much about these viruses because they've only recently been identified. But we do know that if we look at them - their genes we don't see any genetic markers which in the past have been associated with more severity or more transmission to humans. And so that's a good sign.

However like I said, we're following the situation very closely because this is something we're continuing to understand. But at this time we - from the information that we actually do know, it looks like these viruses; these H5 viruses in North America are different than the H5 viruses that have been circulating in poultries and birds in Asia and have caused clusters of human cases in Asia and other places. And some of those cases are really quite severe.

As far as the - is that - did that answer your question?

Donna Young: The differences between the two so that people aren't panicking, knowing that, you know, that these are completely separate viruses.

And then also, as well, going back to the H5N1, how soon before they started seeing that particular virus, which is like I said, very different than the H5N2. But how soon did they see the jump from the H5N1 in birds to humans? If you could maybe explain that a little bit as well. Thank you.

Lisa Fry: Yes, it's really - when we look back historically at the H5 viruses over time, it's really hard to give an exact timeframe like you're talking about. It probably was in poultry for a long time before we hit human cases, but exactly how long, I don't think we really know that.

So, but I think you're right, these viruses, at least from everything we've seen so far, are distinct from the H5N1 viruses that have been circulating in other parts of the world. But we are still being very cautious in our approach to them. But at this point they definitely look different.

Rod Bain: And we turn to our final question of the day and that honor belongs to Chuck Abbott of Ag Insider. Chuck, good morning.

Chuck Abbott: Thank you. I'm hoping the experts today can tell us a couple of things. One is the question of metrics. This is the worst outbreak of high pathogenic avian influenza in the United States since when. I've seen one reference, since the early 80s.

And the other thing I'm wondering, given the biosecurity steps that have been outlined today and the amount of surveillance that's going on, what is this particular outbreak going to end? What's going to stop it?

Dr. John Clifford: So -- this is Dr. Clifford. As far as when it ends, I think we will see warm weather. When warm weather comes in consistently across the country I think we will stop seeing new cases.

Now again, we can't predict what may or may not happen in the fall, but we need to be prepared for the fall, and that's what we're doing.

With regards to that first question again was oh, the worst outbreak. I've had this question before, and basically I would probably say that there was the outbreak - it was in the 80s that was in actually Northeastern part of the U.S. I believe, in Del Marva, Pennsylvania, maybe region of the country. I can't remember exactly where all that was because actually at the time I had just came on board with the agency.

So as that was winding down, but that was probably the worst case of high path.

Rod Bain: Reporters and members of the media, thank you for your questions today and for all of you listening in on today's broadcast. So we now have closing thoughts starting with Dr. Clifford.

Dr. John Clifford: Just again I want to thank everybody for being on the call today and appreciate Dr. Lisa Fry from CDC and Dr. David Swayne joining us from ARS as well.

I wanted to just make a couple of brief points and remind everyone, just like Dr. Fry had indicated, that the risk to humans is low. Our food supply is safe. These birds with high path AR - AI or not going into the human food supply.

And that we know how to address the disease when we find it, and we've gotten great support from our state partners, as well as the industry and, appreciate that. So with that I'd like to ask Dr. Fry is she has any closing comments.

Lisa Fry: thank you again for letting me be on this call with you all. I just wanted to remind everyone about our Web site and our information line. We try to keep our Web site up to date. So if you have questions please check out our Web site - Or if you have questions you can call the 800 CDC Info Line. Thanks.

Dr. John Clifford: Thank you Dr. Fry. Dr. Swayne, do you have any comments?

Dr. David Swayne: Just thank you for allowing us to participate and we really appreciate it.

Rod Bain: Great. And Doctors Clifford, Fry, and Swayne, thank you very much. This is Rod Bain from the USDA radio studios in Washington, DC wishing you all a great day.