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Press Briefing Transcripts

Media Briefing: Update on 2009 H1N1 Flu

September 8, 2009, 12:00 p.m.

  • Audio recording (MP3) MPEG audio file

CDC Media Briefing/Antiviral Guidance 9.8.09

Glen Nowak: Thank you for joining us today.  The Centers for Disease Control and Prevention is issuing some updated interim guidelines on the use of antiviral medications.  And data provided overview of what the recommendations entail.  Dr. Anne Schuchat, Director of the CDC’s National Center for Immunization and Respiratory Diseases and I will turn the podium over to Dr. Schuchat. 

Anne Schuchat: Thanks, Glen.  Thanks, everybody, for joining us this afternoon.  What I want to do briefly is give a snapshot of where we are with the H1N1 situation and then go into more detail about the new guidance on antiviral medicines we’ve issued today on our website and also on  The 2009 H1N1 influenza virus never went away this summer.  It is starting to cause increased disease in the fall.  We are seeing increases in the southeastern states in particular.  Those are states that began school a bit earlier than other parts of the country.  And it is not really that surprising we are seeing this uptick in cases in several southeastern states.  In particular, we have widespread disease in Georgia, Alabama, Mississippi, Florida, among the southeastern states.  We are aware of 24 schools that dismissed students on Friday because of influenza and more than 20 -- about 25,000 students that were dismissed because of the flu.  So it is still around.  It is causing increased disease and it is time to pay attention. 

We do expect there to be a lot of variability with influenza this fall.  We have a few states that are affected now and we need to wait and see what happens elsewhere but there's a lot each of us can do to prepare and be ready when the influenza appears in our -- our own communities.  We saw a lot of variability last spring and so expect more going into the fall.  We wish we could predict exactly what’s going to happen but unfortunately we can’t.  We do know that the virus is unchanged from what we saw in the spring and what circulated in the southern hemisphere and that’s good news because it means that the vaccines that we are working on right now should be very good matches with the H1N1 virus that’s circulating.  So that's good news.  There hasn't been major change in the virus, the 2009 H1N1 virus. 

We are changing some of the ways that states report to us influenza.  We will be asking states now to report hospitalization information and deaths to us.  Those reports will be available on our website and starting next week we’re going to start the flu season again.  So we’ll be beginning this new season, so you will see the spring and summer data on the website but going forward we are looking onward. 

I want to talk briefly about antiviral guidance.  It is important to remember that antiviral medicines are a critical part of our tool kit in countering influenza, 2009 H1N1 influenza virus, and seasonal flu strains.  Important for to you know that most people won't know what type of flu they have because testing is not going to give us those answers.  So our new antiviral guidance really addresses the clinical symptoms of influenza-like illness and suspect influenza without having to differentiate with exactly which strain a person has.  A key point of the antiviral guidance is that hospitalized patients who are suspected to have influenza need prompt treatment with antiviral medicines and we think that can be a very important way to reduce the severity of illness and help those patients out.  We don't want people to wait -- providers to wait until the test results are available but it is important to start those antivirals in hospital patients when you expect influenza.  Treatment is also generally recommended for people with chronic conditions that increase their chances of having a severe time with influenza.  The very young and very old, people with chronic medical conditions and pregnant women in general ought to be treated with antivirals when they have an influenza-like illness. 

The guidance also provides an option for a watchful waiting approach to preventative use of antiviral medicine when high-risk people have been in contact, close contact, with someone with influenza instead of just definitely starting antiviral medicines give providers an option to do what we call watchful waiting.  And wait and see whether fever develops and when fever develops or respiratory symptoms develop to begin the antivirals then.  In our guidance in general, for people with influenza-like illness who are at risk for complications we strongly recommend prompt treatment.  And so the guidance goes through many steps that clinicians and patients can take to reduce the time between when influenza illness begins and when anti viral medicines are taken.  We think that that -- that window is very important and trying to keep it short is going to be helpful.  So we want patients to know the warning signs of influenza where symptoms – where severe presentation is occur, difficulty breathing.  In a child, bluish color of the skin. difficulty taking -- feeding.  Vomiting just doesn't stop.  Or difficulty waking up the child.  Those are some of the warning signs influenza-like illnesses are severe and treatment is necessary promptly.  A very important feature of our guidance is clinical judgment is still important.  This isn't something where we can take clinical judgment out of the equation.  Every patient is different.  We want clinicians to have that opportunity to customize care for each patient.  And so whether a person is able to be seen in the doctor's office or needs to call for assistance we want people to know that clinical judgment is still important. 

A key point from our guidance is that most children, adolescents and adults who have influenza-like illness do not need antiviral medicine.  In fact, if all of those people take antiviral medicine, things may actually get worse.  We have seen a bit of antiviral resistance already with the 2009 H1N1 strain.  And we are optimistic that this won't take off but so far, a critical feature is to use these antiviral carefully so that they can have benefit and not lead to problems.  So the majority of adolescents and adults and most children won't need antiviral development if the develop an inflenza-life illlness and can be cared for with mom's chicken soup at home, rest, and lots of fluids.  People who have complications like pregnancy, asthma, chronic heart disease, chronic lung disease, the very old and very young if they develop influenza-like illness, it is important they consult with the health care provider because antiviral medicines may be very important for them. 

Just to wrap up, it is really important to recognize that antivirals are one important part of our arsenal against influenza but there are other things that can also help.  We constantly need to keep an eye on the situation, continue to understand the patterns of antiviral resistance and patterns of influenza strains that are circulating.  We want to use the antivirals we have as effectively as possible so they will help with mitigating the challenges of influenza this year.  Our goal is really to strike a balance in thousand they are used to benefit people and not to lead to resistance or shortages.  We can't control exactly what happens with influenza.  We wish we could predict and we really wish we could control the whole course of this outbreak but it is important to say that there is a lot we are doing, that we are working with schools and with communities, with public health officials to mitigate the challenges of influenza and be as ready as possible.  Vaccines are being developed.  And of course the seasonal flu vaccines are available really right now and it can be one way we prevent seasonal flu strains from causing illness and suffering.  But while we are waiting for the H1N1 vaccine to be available, those other steps of prevention are still important: hand washing and staying home when you are sick, covering your cough, or cold.  And making sure that you don't spread the infection that you have.  So I think at this point I would like to answer questions that may be available about the antiviral guidance or general situation so we can start in the room here. 

Beth Galvin: I had a couple of questions.  We are getting reports that parents are having a very difficult time finding antiviral medications at their local pharmacy.  Do you anticipate that will be an issue?  Also, you said several times if you are in the high-risk group, use these drugs promptly.  Can you kind of reiterate why it is necessary in the first 48 hours to get the best benefit from these drugs? 

Anne Schuchat: Right.  For people who do need antiviral medicines, timing is important.  Being -- beginning treatment within the first 48 hours of symptoms can really help with the outcome.  People can do better with the influenza illness.  The issue availability of the antiviral is very important.  We are monitoring this at a national level and working with the commercial sector to understand the supply chains and working with the public health community to use the resources we have, the antiviral strategic national stockpile in the states, stockpiles of antivirals to address the spot shortages.  We think the supply of antivirals in the system is adequate for antiviral used for treatment.  It is very important that people know most children, adolescents and adult was influenza-like illness don't need the medicine.  It is just those people with risk conditions where the illness may get worse or people with severe presentations like those hospitalized or who have signs of lower respiratory infection or other severe warning signs that need antivirals.  We think by working together with the private and public sector we can have a good supply available where you need and we really want the public to know most people won't need antiviral medicines goat through the influenza season this year.  Let's take a question from the phones. 

Operator: Please press star one if you would like to ask a question from the phone.  The first question is from Helen Branswell.  Please state your affiliation.

Helen Branswell: Hi, I'm with the Canadian Press.  Thank you for taking my question.  If I could ask a couple please?  First would be -- I'm sorry.  I'm unclear what is new about the guidance today.  What is different about this versus the guidance the CDC would have issued previously? 

Anne Schuchat: Great.  There are some key things that are not new.  The people that need antiviral medicines for treatment are the same as what we recommended in May: people with underlying conditions and people who have worse presentations.  The drugs that we are recommending are not new:  Oseltamivir, Zanamivir, or Tamiflu, Relenza, as the first line treatment, that’s just what we issued in May.  The new guidance emphasizes a few points. They emphasize the importance of prompt treatment for those who are recommended to receive medicine.  And the guidance goes into more detail about how to shorten that time period.  Not just raising the suspicion on hospitalized patients or patients in the office.  But also up front work that a doctor and patient can have a discussion about what the warning signs are so you know how to promptly seek care.  Advice for clinicians about how to set up your office so that you can make sure phone access is available or appointments are available so people who really need to get medicines quickly can get them.  And also, a discussion that may involve considering providing prescription to people who have underlying conditions that put them at risk for a worse time with influenza so they may just need to call you and really talk things over and not come into the office in order to be able to fill that prescription.  A little bit more emphasis on how to shorten the time on treatment. 

The other big change is that in our May guidance we talked about circumstances where preventative use of antivirals may be appropriate.  This was generally when a person who had a risk factor to suggesting a harder time with influenza, close contact with someone with the virus, we recommended it be considered.  In the new guidance we add an option that in those same circumstances instead of preventative use of antivirals, providers might want to consider watchful waiting.  Where they don't necessarily begin preventative antivirals but instead wait to see whether a fever develops or respiratory symptoms occur because most of those people who are exposed are not going to get influenza.  So the watchful waiting was a new addition to this. And then the third point I want to stress is new guidance takes advantage of the whole experience of the spring, whole experience of the southern hemisphere and the circulation of influenza viruses both the 2009 H1N1 and seasonal ones and we were able to make general recommendations for influenza not specific to H1N1 but the influenza that might be any different type and really say that these medicines are the first line regardless.  As you know, Helen, we have had a lot of H1N1 seasonal strains the past year that we were resistant to oseltamivir.  We are not seeing those strains in the southern hemisphere here.  So that fear of the oseltamivir resistance that influences some of our guidance last year we didn't have to incorporate into the new guidance.  Those are principle updates.  Did you have a followup question? 

Helen Branswell: I did.  Relates to the issue you raised a few minutes ago about maybe doing some advanced work.  Could you flush that out a bit?  Are you talking about people -- pregnant women, for instance, people with COPD or whatever having essentially a script in waiting and all they have to do is phone the doctor and say look, I have these symptoms the doctor says yeah.  It is time to start -- get a drug and that's activated in some way? 

Anne Schuchat: Yes, that's right.  That’s one of the exam -- one example where a prompter of antiviral medicines might be possible.  You know, even people with chronic conditions and certainly pregnant women see their health care provider frequently and so we think some of those regular appointments it is reasonable to have a conversation about what to do if flu symptoms occur and that many providers may want to discuss with their patients the idea of providing a prescription that upon a phone consultation might be filled.  This is going to vary by practice, by individual patient and by state because there are different laws about prescriptions and how they work in different states.  We think it is important for the risk groups -- patients to be counseled about the signs and symptoms to be watching for and providers to think through how they can really reach their patients quickly during a busy season in the months ahead.  So certainly for pregnant women and people with asthma and for severe pulmonary disease and heart disease, liver disease, neurologic disease, we were hearing about last week with the tragic pediatric death, in these patient populations, a conversation between the provider and caregiver or patient will be very helpful in sort of setting the stage for what to expect going forward.  There are lots of ways that things will vary by practice and by state and by patient population.  But we do feel that prompt treatment is important and that the doctors' office may get relatively busy and may be reasonable in some circumstances for a phone conversation to be sufficient for prescription to be filled.  Next question from the phone? 

Operator: The next question is from Betsy McKay.  Please state your affiliation.

Betsy McKay: I’m from the Wall Street Journal, thanks. I had a question about the general situation.  I wondered if you could talk about how much of an increase we are seeing in cases compared to your expectations or scenarios you may have laid out. We have seen -- all seen lots of reports of cases, particularly on college campuses, Washington State University has over 2,000 cases of flu-like symptoms.  I wondered if in looking at the scenario you laid out and expectations you, you know, predictions you may have made, over the summer, is this fulfilling any worst-case scenarios or any fears you may have about having widespread illness or peak of infection before the vaccine is ready as the test report suggested could happen?  Thanks.

Anne Schuchat: Thank you, Betsy.  The observations that we are making about disease occurrence are very consistent with what we were expecting.  Based on what we learned from the spring, based on the southern hemisphere experience and based on what we know about influenza we did expect that increased influenza would start to be evident earlier than usual and it might be most evident in school-aged or young adult populations because that's where we really saw a lot of disease in the spring and southern hemisphere.  So these reports about outbreaks in colleges and reports about the increases in some of the southeastern states are quite consistent with what we were expecting.  The good news is that the spectrum of illness doesn't seem to have changed, this range where most people have illness that gets better with home care for a few days.  Some people need to be hospitalized and tragically some people die.  But what I can say is that while this is within the range of what we are expecting we really don't know what the trajectory will be.  We know that some colleges have already seen upticks but the majority of colleges haven't.  Some states are seeing an increase but it is not at a level we would think of as peak at all.  And that we have a big country.  There are many communities that have not seen that much flu yet this year.  Our principle prediction now is that it is going to be a busy and long season and we need to be prepared for the next several months and also the spring.  The good news is that we have been working hard with across government and private sector to ready the schools and universities and businesses and child care centers and so forth to have time for planning.  Some of the schools and universities that have had these outbreaks appear to have been well prepared to be able to address the challenges they have and we really congratulate them for that.  Next question from the phone. 

Operator: Next question is from Miriam Falco.  Please state your affiliation.

Miriam Falco: I’m with CNN Medical News.  Thank you for taking my questions.  I have two.  Number one, about the cases that we have, you mentioned the 25,000 reported so far.  Betsy mentioned 2,000 in Washington State University.  Are these actually all H1N1 cases?  Are these more people showing up because they are feeling ill and there's just a higher uptick of people going to health centers? 

Anne Schuchat: Thanks.  You know, in a typical year, we don't do diagnostic test with everyone with influenza-like illness.  We don't expect the vast majority of people with influenza-like illness to have a diagnostic test that tells them whether it is flu or not and if it is flu, whether it is H1N1.  It’s important to say that the intervention, the antiviral medicines for the high-risk people or staying home and staying away from others with a little bit of TLC and fluids will be important whatever type of influenza it is.  And so that the testing is not so important right now.  I don't know what number of the college students that have been reported to have influenza in the past couple of weeks clearly have the 2009 H1N1 virus.  But what I can tell is we are doing virologic surveillance now, systematically test something people that have the illness or who are hospitalized.  Virtually all the influenza circulating now in the United States is the 2009 H1N1 strain.  Now that is not going to persist for the whole fall and spring.  That's the case right now.  It is something that we will be monitoring.  But right now if a person has influenza-like illnesses the chances are good the 2009 strain of the virus.  Next question from the phone.  Okay.  Let's do next question from the room. 

Operator: The next question is from Mike. Please state your affiliation.

Mike Stobbe: from the Associated Press.  Thank you for taking the question.  Actually, two.  First, doctor, you said earlier, let's see, 24 schools dismissed students on Friday, 25,000 students.  Were those -- were you talking about colleges or other types of schools and what states are they in?  Then I have a second question. 

Anne Schuchat: right.  The -- the -- 25,000 students is from the schools, not universities or colleges, but schools.  The Department of Education is working with CDC on surveillance for schools and for school dismissals.  So that's the source of that data.  The states that -- I think -- I may not actually have with me -- I do.  Okay.  The states where school students had been dismissed include Georgia and Indiana, and Missouri and Tennessee.  I think, though, these may not be complete.  This is the information available as of Friday. And really, this is just -- situational awareness that helps us put in perspective the impact the virus is having right now.  As we have been saying we don't expect school dismissals to be the main way that we handle influenza.  There are many other things that can be done for influenza illness in the school population.  It is one marker for us that local groups are having challenges with the virus and these are steps they are taking.  Recall also that we had a lot more school students dismissed in the spring than numbers today.  The university data that one of the reporters mentioned is through the American College Health Association which has set up a nice surveillance system of a number of universities and colleges and providing that information to the media and we are really delighted that they are doing that.  Next question from the room, I think. 

Beth Galvin: Fox 5, can I wait? 

Anne Schuchat: Absolutely.  See if there is another question from the phone next.  Okay. 

Operator: Next question from the phones is from Alice Parks.  Please state your affiliation.

Alice Park: Hi, I’m with Time Magazine.  I wanted to pick up on something, doctor, you mentioned which was the fact that right now the most common form of influenza is the novel H1N1. But if we know that antivirals are really -- if we know the antivirals are -- seasonal influenza, sorry, is now resistant to Tamiflu, if people that are hospitalized are showing these severe symptoms, would those people be recommended to get some kind of testing?  Or how would you know that they have as the season goes on, that, you know, you won't be seeing more of that seasonal resistant flu versus the novel H1N1? 

Anne Schuchat: We do recommend testing for hospitalized patients but we recommend treatment before the testing results are available. Because early treatment is important.  Important to say that many seasonal influenza viruses are susceptible to Tamiflu.  It is just the seasonal H1N1 viruses that were circulating the past few years that had developed the Tamiflu resistance.  We haven’t been seeing the seasonal H1N1 viruses in the southern hemisphere.  We don't know whether they will be a problem here in the northern hemisphere going through the fall and winter.  A key message for clinicians right now is we believe that the Tamiflu or Relenza will be great first-line treatment.  We do think diagnostic testing for hospitalized patients is helpful and we recommend that.  But we think that for the seasonal H3N2s -- sorry.  and the 2009 H1N1 Tamiflu and Relenza would be fine. Now we have a question from the room.

Alice Park:  I remember. If you think that you have the flu this summer, if you are certain you have the flu this spring or summer, do you have any cross-protection?  Are you okay going into the fall?  Do you still need the H1N1 flu vaccine when it becomes available? 

Anne Schuchat: This is such a common question that we have – and it’s a really important one. I wish I had a better answer.  We think that you -- if you are in a recommended group that you do still need the H1N1 vaccine going forward, and that if you are in a recommended group you do still need the seasonal flu vaccine.  Most of the influenza-like illness that is circulating does not get a diagnostic test.  So we don't know for sure whether what the cough or cold people had this summer exactly what that was. We had a lot of attention to H1N1 but you know, in the southern hemisphere is where they were testing and they saw a lot of other respiratory viruses.  Not everything that sounded like influenza was actually influenza.  When I mentioned the virus was essentially the only influenza virus we are seeing, it is true but it is not the only respiratory virus that is circulating. So the key thing for people is that we do think that you will need an H1N1 vaccine if you are in one of the recommended groups.  And to remind folks we recommend – we’re recommending H1N1 vaccine when it becomes available for health care workers and those with emergency medical service personnel for pregnant women and for parents or other close contacts and caregivers of children under six months of age.  And for all children between the ages of 6 months and young adults, 24 years of age.  And for 25-year-olds through age 64 who have chronic medical conditions that increase the risk of a bad outcome from influenza.  That's a lot of people and we know that many people did have a respiratory illness this summer but we still have those -- think those people should go ahead and seek the influenza vaccine. 

Alice Park: Do you have any evidence they have some cross-protection or maybe if they get sick againworse time of it?  Less severe time of it.

Anne Schuchat: We don't have information about that right now. So I think that it is -- it is a big challenge.  But we think that the vast majority of the country has not yet had H1N1 disease and the vast majority of people are at risk for seasonal influenza viruses as well. Our vaccination recommendations are based on those principles.  Next question from the phone.

Operator: Next question from David Brown.  Please state your affiliation.

David Brown: Yes.  I'm with the Washington Post.  Thanks for doing this.  Dr. Schuchat, could you say a little something about where current shortages of the antivirals are?  And how the -- what CDC is going to do should they develop, given the importance of immediate treatment, how you are going to get antivirals to a region?  Certainly, last spring, you know, in the Washington area, it was completely sold out. Some pharmacy had 100 prescriptions waiting to be filled. The disease hadn't spread very much. 

Anne Schuchat: Our strategy for dealing with antiviral supply issues and spot shortages issues has two prongs.  One about demand and one is about supply.  The demand side of the story is to really promote appropriate use of antivirals. They can be lifesaving for treatment of people hospitalized or people who had underlying conditions that increased the risk of a bad complication from flu. And really are not necessary in the vast majority of children, adolescents and adults who have the influenza-like illness and don't have a bad presentation or one of the risk conditions. We are addressing supply by working with both the commercial sector to understand where products are and how quickly they can be restocked in pharmacies and the public sector with the strategic national stockpile asset to get antiviral medicine to where they are needed.  So in many of the health departments, we are learning the lessons from the springs, best practices some of the states had in making sure their antiviral stockpiles were out there in their pharmacies, grocery stores, or accessible to people through local health departments so that when there weren't assets in the commercial sector, the public sector assets were acceptable.  I think that this is a question both supply and demand and a critical issue is to just remind people that the vast majority of us that have an influenza-like illness don't need the antiviral medicine.  Next question from the phone. 

Operator: The next question is from Shannon Pettypiece. Please state your affiliation.

Shannon Pettypiece: Hi. I'm with Bloomberg news.  I have two questions.  One was why is it that you are seeing an increase in the south?  I know you said some schools go back earlier there than elsewhere. I wonder if there's anything else having to do with climate that may also explain that.  My other question was about the antiviral resistance and if you could explain a little bit more of where you are seeing that. And you know, number of cases or areas that you have seen that in.

Anne Schuchat: Right.  The reason for the early increase in disease in the Southeastern United States isn't known. We have two possibilities.  One possibility that we are exploring is that schools reopened a bit earlier in southern states than they did in the northern part of the country. And perhaps that gave more of a chance for mixing to occur in earlier disease.  But another possibility is that the southeastern states were not that heavily hit in the spring and so they may just be getting their spring wave right now as opposed to New York City or Chicago or Seattle that saw a lot of the disease last spring. It could be either of those or both of those or something else. Your other question was about antiviral medicines.  I’m trying to remember.  Could you remind me --

Shannon Pettypiece: Yeah.  You said you saw antiviral resistance--

Anne Schuchat: resistance, right.  So far there has been a handful of antiviral resistance around the world really caused by the 2009 H1N1 strain. The vast majority of the resistant occurrences have been in people that were on antivirals at the time, taking antivirals for preventative reasons, for profalaxis.  And so far this hasn't been widespread and we continue to look and it is important for people to know it might become widespread.  One of the reasons we are looking that we have that fear.  But so far it is just a handful. I don't have data on the specific antiviral resistance today. Maybe we will have that for a future call.  I think I have time for two more questions, if there are any left on the phone. 

Operator: the neck question from the phone is from Diana Debrovner.  Please state your affiliation.

Diane Debrovner: I’m with Parents Magazine. Thanks so much for taking my question. You pointed out that most children don't need antiviral treatment and will do fine at home.  I'm wondering if you could give some more specific guidance about when parents should call the pediatrician if their child has symptoms very flu-like, do they only need to call if their child falls into a risk category or has one of the symptoms of a more severe infection?  Otherwise should they just treat their child at home on their own or is it worth a call to check in with the pediatrician? 

Anne Schuchat:  You know, every family is different.  And each provider may have a different preference. Let me tell you warning signs parents need to know about so that they can be on the alert with their children and their children's health.  Warning signs in children include fast breathing or trouble breeding, bluish skin color.  Not drinking enough fluids. And not waking up or not interacting in their normal way.  Being so irritable that the child doesn't want to be held.  And flu-like symptoms getting better and then getting worse. That can be a warning sign for a second infection on top of the flu.  Those are key warning signs that parents should be aware of.  We also think that the youngest children, children under 2, are at risk for influenza complications and it may be harder to spot those warning signs in the youngest kids and so consulting with a provider in the youngest kids is important. Children over 5 do pretty well with influenza-like illness.  Children 2 to 5 are sort of in between.  We think that clinical judgment is still important and parental judgment is important. Those warning signs are clues that parents should be on the alert and keep an eye out for them. 

Diane Debrovner:  One more quick question.  If a child had flu-like symptoms in the spring and did have a rapid flue test that showed it was influenza a, is that -- a sign that they would not need the H1N1 vaccine?  Or do they -- should they still go ahead and have it? 

Anne Schuchat: You know, our recommendation at this point is that they go ahead with the influenza vaccine -- H1N1 vaccine this spring.  So the -- rapid tests are not perfect either positives or negatives and we do actually recommend that.  I think we have time for one last question on the phone. 

Operator: Next question is from Tom Fudge.  State your affiliation.

Tom Fudge: I am with KPBS public radio in San Diego.  I have a question about something that you touched on -- vaccines.  I think you said at the beginning that because H1N1 has been quite stable, the vaccine will be a good match.  Can you expand on that a little bit?  How sure can you be, can we be, that the vaccine will hit it right between the eyes? 

Anne Schuchat: The influenza viruses that have been tested as recently as a couple of weeks ago are extremely close matches essentially the same as the viruses that were -- used to prepare the vaccine.  That doesn't mean that a couple of months from now or a couple of weeks from now the virus won't change.  That's really one of the frustrating things about influenza.  It can change.  Based on everything we know today, we are expecting a really good match between the H1N1 vaccine and the strains circulating.  And that is very good news because the better the match, the higher the efficacy of the vaccine.  So thanks, everyone, for participating and we will be back soon. 



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