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Press Briefing Transcripts

CDC Briefing on Public Health Investigation of Human Cases of H1N1 Flu (Swine Flu)

May 4, 2009, 1 p.m. EST

  • Audio recording (MPEG) MP3 audio file


Operator: Good afternoon, and thank you all for holding.  At this time, your lines have been placed on listen-only until we open up for questions and answers.  Please be advised, today's conference is being recorded.  If you do have any objections, you may disconnect at this time.  I would now like to turn the conference over to Mr. Glen Nowak.  Please go ahead, sir.

Glen Nowak: Good morning.  Welcome to the press briefing on the novel H1N1 influenza virus. around the world.  Today we have Dr. Richard Besser, Acting Director of the CDC for an update.  And I will turn the podium over to Dr. Besser.

Richard Besser: Thank you for coming to today's update.  As I've said, each day, this is a situation of much uncertainty, but with each day, we learn a lot more information to help us understand this outbreak and understand the best means of control.  While we're not out of the woods, we are seeing a lot of encouraging signs, and I want to share with you some of that information.  Let me start with the case updates.  And today I'm going to, in addition to giving you information on confirmed cases, just give you a sense of what we're seeing in the area of probable cases, and then we're going to be looking in the future to be able to post on our website some more information about probable cases.  The reason for that is that what we're seeing -- a probable case is someone who has the flu-like symptoms and is tested with regular flu testing and comes up negative, so there's no strains.  It's a very good test.  We're seeing that over 99% of those are ending up confirmed.  So, that's going to be useful information to get a sense of what's happening across the country. 

We continue to see spread widely across the United States.  There are 286 confirmed cases in 36 states.  That's an increase of six states from yesterday.  And we're seeing over 700 probable cases in a total of 44 states.  This likely represents an underestimation of the total number of cases taking place across the country.  In order to be counted, you have to have your flu-like symptoms and see your doctor and be tested.  And we know that for a lot of people, those steps do not take place.  And because this is flu, the situation will change rapidly.  The median age of confirmed cases is 16 years with a range of 3 months to 81 years.  The most recently confirmed case is May 1st.  There are 35 known hospitalizations in the United States with the one reported death.  62% of the confirmed cases are under 18 years of age.  The World Health Organization earlier today was reporting 898 cases in 18 countries.  I like to each day put this in context with seasonal flu.  With seasonal flu, we see in the United States over 30 million cases.  We see 200,000 hospitalizations and, on average, 36,000 deaths. 

We have teams working in Mexico as part of the tri-national effort there, and they're hard at work to try and understand the situation in Mexico.  What we're hearing from Mexico is what has been reported in the news, as well -- it appears things are leveling off in Mexico.  They are reporting less activity in Mexico City.  But as we're seeing here, they're seeing different things in different parts of the country.  So, some of the encouraging signs -- the situation in Mexico is encouraging.  Some of the initial lab studies are encouraging, and Dr. Cox talked about those earlier, the lack of the factors in the virus that has been associated with more severe disease in previous pandemics.  We're not seeing those.  We're not seeing a lot of variations between the isolates, and that's very helpful as we start to think about the issues around vaccine and developing vaccines.  And so far, the severity of illness we’ve seen in this country is similar to that of flu, and that's very encouraging. 

Let me talk a little bit about some of the public health actions that we've been taking, give you an update on those.  As we said last week, the Strategic National Stockpile, the first 25% allotment is being distributed across the country.  At this point, all states have received their share of the stockpile.  There is additional resources, part of the share for Guam and American Samoa is still in process.  We have distributed test kits to every state, and this will allow for more rapid diagnosis at the state level.  What happens when a state receives their kit, we will work with them on the first five isolates to make sure that the test is up and running properly, and once that's done and we've confirmed their ability to use the test kit, then they're able to do that testing all on their own.  We have 81 folks from CDC who are in the field assisting state and local public health as well as 16 of them who are in Mexico.  We have 35 more people who are pending deployment in the very near future. 

Vaccine is something we've been talking about every day, and I just want to clarify that we are doing all of the steps that are necessary should we decide to produce a vaccine.  The decision doesn't need to be made now whether to manufacture a vaccine and clearly doesn't need to be made now about should people be vaccinated for next season.  What needs to be done now are the steps of determining which virus you want to use, growing up seed stock of that virus and having the conversations with manufacturers around what would need to be done to manufacture a vaccine.  And those things are all taking place. 

There have been questions each day about World Health Organization and what phase we're in.  We're currently in phase five.  And the question of whether the World Health Organization will move to phase six.  What they're looking for is are they seeing sustained human-to-human transmission outside of more than one World Health Organization region.  So, they see this in this region, which includes Canada, the U.S. and Mexico, and they're looking to see, is that something in any other region.  So far, they haven't seen that.  They've had case reports in many countries around the world, but they have yet to see sustained human-to-human transmission.  So, were that to occur -- and we anticipate at some point, it will, given that flu viruses spread easily from person to person -- should that occur, they would raise the alert level to indicate that we have met all the criteria for a pandemic.  That would not change what we're doing in the United States.  We have this virus spreading in our communities.  We continue to take aggressive action based on it being in our communities.  And as we learn more, we continue to adapt and adjust our recommendations and our guidance so that they are appropriate for the situation that we're seeing. 

So, going forward, here are some things that we're thinking about and things that are important.  One is what happens in the southern hemisphere.  We have the flu season here as our winter, as in the southern hemisphere, they have flu season in their winter.  So, we'll be working very closely with the international community to understand what happens to this virus over the next few months as flu season begins in the southern hemisphere.  That will tell us a lot about whether the virus is changing, whether it's becoming more severe and what measures we might want to take in the fall.  We expect that all states will likely have confirmed cases.  They don't yet, but it's a matter of time.  Flu viruses don't respect borders, and with travel, we expect that there will be more cases.  To put this in context, I keep saying that it's looking like it's along the severity of seasonal flu.  We know that each year with seasonal flu, people are hospitalized and people die, and unfortunately, we expect here that with a virus of this severity that there will be ongoing hospitalizations and that there will be additional deaths.  It's important that as we talk about the encouraging signs that people don't take that as an indication that they have to let up their guard.  Personal responsibility, the things that we talk about every day about hand-washing, about covering your cough with your sleeve and not with your hand, about staying home when you're sick, about keeping your children home when they're sick, those things are critically important.  They're important every flu season, but they're really important now, when we have a virus that we're just learning more about, that's spreading through our communities.  These measures will help to keep people healthy and decrease the number of people around them who get sick.  So, you know, we're going to continue to tell you what we know when we know it.  Information changes daily.  And during this briefing every day, we hope to be able to address your questions.  So, I'll stop there and open it up for questions.  First here in the audience.  Yes. 

Beth Galvin:Hi, Beth Galvin with Fox 5.  I was wondering what you've seen in the lab, what can you tell us?  Has anything changed as far as severity, as far as, you know, anything else you're testing for, antiviral resistance? 

Richard Besser:Sure.  Dr. Nancy Cox is here, who is Director of the Division of Influenza.  Would you mind coming up and answering that? 

Nancy Cox: Sure.  We're keeping very close tabs and looking at all of the virulence markers and all of the resistance markers for antiviral.  And so far, we have very good news.  We haven't seen any changes that would cause alarm.  So, the viruses are remaining very consistent with respect to their genetic properties and their resistance properties, their susceptibility to the antiviral drugs and their susceptibility to the neuraminidase inhibitors but resistance [inaudible]

Richard Besser: So, Tamiflu and Relenza, we're not seeing any resistance in that area.  Another question here in the audience and then we'll go to the phones.

Reporter: I actually have two questions.  One is, how many health care workers in the U.S. have been infected, and that being either from the community in that they may be a danger to their patients or from work exposure in a hospital or another health care facility? And my second question has to do with a recent report from some health care workers union.  They surveyed 104 facilities in 14 states and found that one-third of the union leaders said there was no pandemic preparedness plan in their facility.  So, I'm wondering what you're seeing in terms of hospital preparedness.  And I'm sure they're trying to prepare now, but that was supposed to be taking place for a number of years.

Richard Besser: Right, right.  I can't answer the question in terms of number of health care workers who have been infected.  I can see if for tomorrow we can have a sense of that.  We haven't been hearing about large numbers of health care workers, but I don't know whether we have a tally of the total number of health care workers.  You know, in terms of facility preparation, what we've seen over the past number of years is that there's been variability in terms of how people approach emergency preparedness in general and how many have emergency response plans for whether it's a new flu or whether your facility's hit by a tornado or a hurricane.  It's important that those facilities that haven't done that work do it, because you cannot predict what emergency will come along, and there are things that institutions can do to be ready and decrease the impact on their facilities and their communities.  Let's go to the phones. 

Operator: Thank you.  Helen Branswell, the Canadian Press, please go ahead.

Helen Branswell: Thank you.  I was hoping you could talk to us a little bit about numbers.  I'm wondering how long numbers are really relevant.  I know it's helpful to know where the virus is spreading, but you know, confirmed tests will always be just a tip of an iceberg, and I'm wondering how -- if you think maybe people are sort of overfixating on numbers.

Richard Besser: Thank you for that question.  I think that that really raised a very important point.  It's important for an area to know if they have H1N1 disease in their community.  That's really important, because that can guide some of the actions that they take, and it's important for us, as we've been trying to study and understand how this virus moves and what type of disease it causes, but once you have widespread disease and once you have this in each community, the numbers become much less important because the actions you want to take, you should be taking.  And so, we're going to be trying to move away from focusing on the numbers and looking at the distribution across the country and how this outbreak progresses around the country.  Another question from the phone? 

Operator: Thank you.  Marin McKenna, CIDRAP News, please go ahead.

Marin McKenna: Hi.  Thanks so much for doing this.  To follow up on that question, since you're going to be talking more about probable cases, since they seem so likely to turn into real cases, do you expect any difficulty with a lack of match between the U.S. numbers and the WHO's numbers for different countries?  And as a second question, can you give us more detail as to what you'll be looking for in the southern hemisphere? 

Richard Besser: In terms of the World Health Worse, our relationship with the WHO, through them and with Canada and Mexico in particular has been really outstanding. I was on a conversation with the Director General just about a half hour ago to understand what she's seeing and let her know what we're seeing.  And at the technical level, we talked about those issues of what is the testing strategy here, of what are we doing in that regard.  Over time, the more cases you have, the less resources you really want to put into the testing.  One of the strategic approaches that I've talked about over the course of the past week is you want to put your investments and your efforts towards those things that are going to make a difference in people's health.  You always want to be re-evaluating that.  Early in an outbreak, individual case testing and detection is very important.  It's very important in terms of understanding who is at the greatest risk, are there groups that are having more severe disease?  You want to make sure that you're gathering case information.  At some point, though, you want to transition to understanding the movement through populations, and you don't want to both use up laboratory scientists' time and expensive resources where they're not going to make a difference.  So, those discussions are things we have all the time with the World Health Organization.  In terms of the southern hemisphere, there are a number of things you want to look at.  One is what are the attack rates?  Does this become a predominant strain while there are other strains circulating?  Here in the United States, this is occurring at a period that we're at the very end of the flu season.  And so, there aren't a lot of other flu viruses that are around and competing with it.  What happens when it goes into countries where there are other flu viruses are causing disease?  What happens in terms of resistance?  What happens in terms of subtle changes in the virus?  What impact could that have here on a vaccine strategy?  So, those are just some of the things that we'd be looking at.  Here in the room. 

Cece Connolly: Cece Connolly from "The Washington Post."  I understand you have not made a decision whether or not to go forward with large-scale vaccine production, but at the same time, you all have been clear that you're positioning yourselves if you need to make that decision.  That being said, you're heading into uncharted territory here.  You're talking about the prospect of two flu vaccines being simultaneously produced and administered on a large scale.  Can you start to talk about the decision-making process and what kinds of things you're going to have to think about, about potentially pulling something like that off? 

Richard Besser: Right.  Well, we're already working to ramp up the production of the seasonal flu vaccine so that, should we decide to manufacture a vaccine for the H1N1, we'd be able to do that.  It's going to be a big decision to decide whether to do that, given the resource implications and how much is unknown and uncertain.  And so, thankfully, the steps that we're taking now will put us in position, should we decide to move forward on that.  This is involving a work group from across the department.  It's involving engagement with industry.  And we don't have to make that decision right now.  Apart from the decision of do you manufacture a vaccine, if you decide to go down that road, it will then be, who should get that vaccine, how much vaccine do you make, what are the implications for the global community in terms of that there?  I've been saying that moving to a stage or phase six doesn't really change what we do here.  What it really does do is recognize that infectious agents don't recognize borders.  And we as a country have far greater resources to address something like this than much of the world.  And so, we really want to ensure that the rest of the global community and World Health Organization is taking a really marvelous lead in this area, is thinking about how do we support countries that don't have as many resources to respond.  Next question from the phone. 

Operator: Thank you. Betsy McKay, "Wall Street Journal."  Please go ahead.

Betsy McKay: Hi, Dr. Besser. Thanks very much.  In light of the course the disease is taking right now in the U.S., I'm wondering if you're considering revising any of your guidance, like the school guidance?  Secondly, I was wondering if -- you said that 62% of the cases right now are under 18 years old.  And in general, we know that this is striking younger people.  I'm wondering if that's something in particular about this virus or is it just the way in which it entered the United States, with you know, a lot of students coming back from Mexico?  Thanks. 

Richard Besser: Thanks very much.  So, the issue of school guidance.  Our approach, as I've said, has been very aggressive.  You may only get one chance to get out in front of a new infectious disease, and so, that's what we've been doing all along.  But as we've gathered more information, we're continually evaluating our guidance.  As a pediatrician and as a parent, I know the place where I want kids is in the school learning, but you want to make sure they're doing that in a way that their health is protected.  When you think about closure of schools, there are a couple of things you're trying to do.  One is protect children from getting this flu from each other and the other is trying to prevent children in being amplifiers in the community.  Children tend to share infectious diseases with each other, and then they go in the community and they tend to multiply this in their communities.  What we're hearing is that schools that are seeing clusters, that are seeing cases, it appears that the virus is already pretty well established in those communities.  And so, closing schools as a means of not letting it spread through the community isn't very effective.  And what we're also learning is that the spectrum of the disease, the severity is more similar to what we have seen with seasonal flu.  With that information, we are looking at our school closure guidance and we're having very active discussions about whether it's time to revise them.  One option would be to do something like they're doing in Seattle, and that they're discussing in other parts of the country, and that's to really push hard on the personal responsibility so that parents in the morning are checking to make sure their kids are not sick, and if they're sick or starting to feel a little sick, they're staying home and they're staying home for a good seven days of that illness.  Even if they're feeling better.  Having school -- really look, and teachers look around that room and see, are any of these kids looking sick?  And if they are, send them home until it's certain whether or not they're sick.  Then using schools as a way of really teaching the importance of hand-washing and covering your cough.  These are things that schools can do.  It's an approach that Canada uses.  So, we're in active discussions on this.  You know, each day that we get more information makes us feel more comfortable about the progress of this outbreak.  And you know, I would expect that as we get more information, we will be looking to revise that guidance in particular.  Your other question had to do with the age distribution.  And you know, we look at the age distribution and we asked some of the same questions you were asking, and that's, is the age distribution having to do with how the virus was introduced, with more young people going to Mexico, a lot of spring break travel, and then coming back?  Is it a delay?  Could we see this going into an older population later as this spreads through the community?  And we're watching for that.  Other possibilities are that, perhaps, older people have some protection, because each year we're all exposed to flu viruses and you develop some immunity.  If there were some cross protection, that's another thing that might explain why we're seeing more in younger people and less in the older folks.  But that question isn't – we don't have a firm answer on that yet.  Another question from the phone. 

Operator: Thank you.  Brian Walsh, "Time" Magazine, please go ahead.

Brian Walsh: Hi, Dr. Besser. Thanks for taking the call.  I know this situation is still one that's evolving, but I was wondering if you could look back at this last week, week and a half, at this response by the CDC and any lessons you've learned in terms of changes you would have made, in terms of how you would have responded to this.  Anything you can take from this experience for inevitably, the next emerging infection or emerging pandemic? 

Richard Besser: One of the things that we do, whenever there's an outbreak or even when we're exercising, we do what's called an after-action review.  We review every aspect of the outbreak.  During the event, we ask people to collect ideas of things that we are doing that didn't work, so we can make sure to change our procedures and not do them anymore, and novel things that we've tried that have worked very well, so we can make sure to incorporate that in our plans moving forward.  And we're going to do that here.  One of the things that has struck me incredibly over the past two weeks is how prepared we were at the state and local level, how we didn't have to start by explaining to people what influenza was and how it transmitted.  We didn't have to talk about how you set up to responseto a very complex, unknown outbreak.  There's been an enormous investment around the country in state and local public health in emergency preparedness.  A lot of it following the criticisms from Hurricane Katrina and our ability to respond.  And those systems have allowed for a very rapid response.  Those systems have allowed us to now very rapidly distribute the Strategic National Stockpile.  The states know what they're getting.  They're going to know how they're distributing that.  State laboratories know how to receive a test kit and know what that means and know how to fit into a broader network.  The communication materials that we've been sharing over these past two weeks are really modifications to communication materials that were developed in the event that we had an outbreak of H5N1, the Avian strain.  So, those preparing efforts have been enormously rewarding.  And while no microbe reads the plan or follows the plan it allows us to respond in a very nimble way.  Another question from the phone? 

Operator: Thank you.  Donna Young, "Bio World Today."  Please go ahead.

Donna Young: Hi, yes, thank you for taking my call.  I had a question again about the vaccine.  If they do make a decision to go forward with a vaccine, and it's the vaccine that's against the current virus, what happens when the virus, if it mutates and comes back as a, you know, as a completely different virus?  How will that vaccine protect people?  And then also, going back again to when you were talking about the immunities that people are building up.  Isn't there a chance with all of this now, you know, in trying to keep people away from getting the virus, that maybe, it's maybe doing more harm than good if they could get the virus now at, you know, when it's milder than when it may come back later as something more heavy-duty, like in the 1918 flu? 

Richard Besser: Let me take your first question first about the vaccine.  You know, each year there's a process for selecting what strains are going to be in the next season's flu vaccine.  And Dr. Cox is part of that process and is part of the World Health Organization committee that helps select that strain.  Some years, we get it right on target, and some years not as much.  And a lot of that has to do with the subtle changes that take place in the virus over time.  And so, your question is right on target.  You could see a major change in the virus that makes the vaccine less effective.  Do you want to add anything to that?  No.  The issue about exposure now and whether it's protective -- there has been work done looking back at previous pandemics.  I think 1918 in particular.  And some have suggested that in the early first wave, some of those people may have been protected from later disease.  There are a number of unknowns right now.  One is, will there be later disease, and if so, will it be more severe?  But it's very difficult right now to say that you would not want someone to get -- that you would want someone to get this infection, given what we know about flu viruses and the fact that each year, there are a lot of people who get very sick and many who die.  And so, we don't have a firm answer to that, but it's our belief that protecting people from this infection is the right way to go.  Two more from the phone.  Telephone? 

Operator: Thank you.  Malcolm Ritter, "Associated Press," please go ahead.

Malcolm Ritter: Hi.  Thank you very much.  Dr. Besser, can you tell us anything more about those hospitalization cases?  How many of these patients have underlying conditions other than the flu, and how many went on ventilators?  Were they hospitalized for problems you wouldn't normally see with seasonal flu?  And have any of them been released? 

Richard Besser: All I can share with you about the hospitalizations, because we don't have detailed case reports on all of the hospitalizations, is that it appears the age distribution is the same or very similar to what we're seeing with the cases in general, but I can't -- I don't have additional information for you now on underlying diseases and those kinds of things.  Another question from the phones? 

Operator:Thank you.  Tom Costello, NBC News, please go ahead.

Tom Costello: Hi, doctor, thank you.  I just wanted to clarify the incubation period.  Last week, we were told you thought it was somewhere between two and seven days.  Is that still the case?  Can you give us an update on that? 

Richard Besser: Okay.  Yeah.  Yeah, that's correct, we're still going with that estimate.  Last question here in the room?  Or is there someone who hasn't asked a question?  Yeah? 

Michelle Marill: I'm Michelle Marillwith Hospital Employee Health newsletter.  I just want to follow up with questions about the vaccine.  Historically, we've seen some reluctance on the part of health care workers to receive the seasonal flu vaccine.  We have some interesting history with vaccines from the smallpox vaccine and the earlier swine flu vaccine.  Do you think there will be a distrust in this vaccine or do you think people will embrace it because it might prevent the spread of something that could become very serious? 

Richard Besser: It's very important as we develop vaccines, whether it's for this H1N1 disease or for any infectious disease, that we take proper precautions and do safety testing and do all we can to ensure that, you know, something we're injecting into someone is safe and it's going to prevent the illness that's intended.  And that's critically important.  As a pediatrician, you know, I don't think that there's anything that I do for my patients that has more of an impact on their health than assuring that they're vaccinated when they start school.  That I know saves lives.  I've worked in clinics around the world and taken care of children who had vaccine-preventible disease, and it just breaks my heart.  That's something we know that works.  But we have the responsibility of assuring that any vaccine we give to people, we believe fully that it's safe.  Thank you all very much.  Appreciate it. 

Operator: Thank you.  This does conclude today's conference call.  We thank you for your participation.  You may now disconnect your lines. 




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