CDC Briefing on Investigation of Human Cases of H1N1 Flu
July 17, 2009
Operator: Welcome and thank you for standing by. At this time, I'll put this on a listen-only mode. You can press star-1 to ask a question. This call is being recorded. You may begin, sir.
Dave Daigle: Thank you. Today, we're going to provide an update on 2009 H1N1 influenza. With us today is our Dr. Anne Schuchat, director of the National Center for Immunization and Respiratory Diseases at CDC, Dr. Jesse Goodman, chief scientist and deputy commissioner, FDA and Dr. Bruce Gellin. We're going to start with short remarks from Dr. Schuchat.
Anne Schuchat: Good afternoon, everyone. I appreciate the chance to provide an update. What I want to do is share with you a little bit more information about what we're seeing and what we're learning about the virus and some comments about vaccine distribution planning efforts, and we have arranged to have colleagues from across the Department of Health and Human Services join me today. Because, as you know, in some of our past briefings we have had questions about vaccine development and so forth. The last time that I spoke with you, I had mentioned that this virus is not going away. Based on our continued information in the United States, this is still very much the case. The patterns we have been seeing with the 2009 H1N1 virus are quite different from seasonal influenza. I want to expand a little bit on that and tell you that we have learned a lot about this virus from experience here in the U.S. and what we're seeing in the Southern Hemisphere and that information is helping us focus our concern on preparing actively for the fall. What have we learned? This virus is continuing to cause illness and outbreaks in the summer months here in the U.S. In temperature and humidity conditions, they are not very favorable to seasonal influenza virus transmission. We're seeing disease, including severe illness and fatalities in a generally younger population from what we've seen with seasonal influenza with relatively limited illness infections and serious consequences in the elderly but as we have said, there are higher attack rates of illness and hospitalization in younger adults and children. And those have been one of the reasons we have been quite concerned in the spring and continuing on into the summer. We're particularly concerned about pregnant women, for example, both in the United States and now also from some reports in the southern hemisphere, we know of life-threatening illnesses or some fatalities that have occurred. Among other adults we're seeing both adults with underlying risk factors of complications of influenza and some healthier folks have gotten severe influenza. So, this virus is continuing to cause illness here in the U.S. even in the summer and continues to affect a generally younger population than what we see in terms of the seasonal influenza.
We do expect there to be an increase in influenza that occurs this fall, perhaps earlier than what we see with seasonal influenza. In particular, we think there may be challenges when people return to schools and our communities get back into the sort of the regular times with lots of kids congregated together. As you heard last week from the Secretary at the Influenza Summit, we're in an active stage of preparing ourselves with the government, working with the private sector, and we also want individuals and families to be planning and preparing. But we need to remember that influenza is unpredictable, including the new strain, the 2009 H1N1 virus, and we don't know the extent of the challenges that we'll face in the weeks and months ahead. We do know that there's a lot we all can do to be ready as ready as possible to face those challenges. It's through the coordination and collaboration and partnership that we expect a lot of progress. I want to briefly mention the southern hemisphere. As I said before, we have people and partners working actively in the southern hemisphere to understand this new influenza in the context of their usual winter flu season. We are seeing the strain of the 2009 H1N1 virus continue to be a problem in several countries. It is being seen together with seasonal influenza viruses in some places, it is dominating in other places. It's still early in their seasons. Many of the southern hemisphere countries have seasons that typically peak in August. We haven't seen the end of their flu season. In the reports we have from the southern hemisphere, it tends to affect generally younger people, sparing the elderly to a great extent. The illness that's being reported includes a spectrum just like we saw here, a spectrum that includes severe respiratory problems. We have heard of intensive care units with many people, many young people who have this new H1N1 virus. And we also know that the ability to manage severely ill patient can vary substantially from one country to another country. The challenges of managing this in different locales is one of the issues being addressed.
A few comments about the vaccine and what's going on in that arena. Last week the department of Health and Human Services secretary announced plans for a voluntary vaccination program in the fall. Assuming availability of a safe and effective vaccine. My colleagues on the call with me will be able to provide some answers to some of your questions in more detail. In general, I want to say a few things about where we are with planning for a vaccination program, with our partners in public health. We have provided planning scenarios for state and local publication so they begin with working with communities, the health system, the department of education, to identify venues for vaccination. It's very important to have some concrete scenarios to plan with. So, we released those last week to help people focus their planning efforts. Funding for state and local governments have been announced. The states and large cities will receive resources to help them plan for vaccination and for other interventions and to strengthen their surveillance and communication efforts. Later this month on July 29th, our Advisory Committee for Immunization Practices will be convening here in Atlanta. They'll be deliberating on recommendations, for which population should be targeted for vaccination with the 2009 H1N1 vaccine. And they'll also be deliberating whether prioritiziation or tiering of potentially limited vaccine supply would be appropriate. It's the kind of question that our Advisory Committee for Immunization Practices addresses all the time for other vaccines and they also do this kind of deliberation for the seasonal flu vaccine. And so we're convening in an emergency or on an off cycle meeting later this month for them to deliberate about those matters. At the CDC, we're continuing to work with state and local public health, health care provider organizations, and the private sector, to assure that we're ready as possible for expected increases in illness that may occur in the next weeks or months. And we're also expecting to be updating guidance for clinicians, institutions, laboratories and others over the next several weeks. We're trying to take advantage of what we have learned so far about how this behaves and the impact and effects of our intervention so that our next round of interim guidance can be as practical as evidence based and useful as possible to all of our partners as we go forward into the fall. I want to make sure that you know that the government is working together around the H1N1 challenges and particularly around the vaccine development, testing, licensure and program planning. I have colleagues from the National Vaccine Program Office and the Food and Drug Administration who will be able to share information depending on your questions. So, the main message is the virus isn't gone. We're concerned that there will be challenges in the fall. We're working hard to be ready for them. There will be roles for government and but also roles for communities and individuals. I think we can take questions at this point.
Dave Daigle: We'll take questions now from the reporters.
Operator: Thank you. If you would like to ask a question, please press star-1. You will be prompted to record your name. Again, press star-1 to ask a question. Star-2 to remove your question. One moment, please. Our first question comes from Helen Branswell with the Canadian Press.
Helen Branswell: I wanted to ask Dr. Goodman a question about vaccine time line if I could please. Dr. Goodman, vaccine manufacturers are a being bit parsimonious about when they'll be conducting clinical trials about the vaccine. I wonder if you can give us a sense when the FDA expects to be getting data and start making decisions about the vaccine, whether the FDA will consider at this point, moving ahead without the kind of data you would normally expect to have to license a strain change.
Jesse Goodman: Can you hear me?
Helen Branswell: Yes.
Jesse Goodman: Helen, thank you for that question. First of all, we think things are proceeding well. We're having a meeting next week to discuss some of the clinical trial plans that are ongoing. And we expect initial trials to be starting very shortly. There's a lag time of 21 days after people get the first dose and blood drawing after that, that means that you know, we're anticipating that even if things go well, we're not going to have the data for some time. Now, we do view the license processes and the license vaccines -- again this will be discussed more next week. We have a long record of safety for these vaccines. And we do view this similarly to a strain change.
Dave Daigle: Next question, please.
Operator: Thank you, our next question comes from Maggie Fox from Reuters.
Maggie Fox: Yesterday, Baxter reported that they were having trouble meeting all of their production goals. Do you anticipate any problems in securing enough vaccine supply for the United States? And can I ask a question about what's going on in Argentina as well?
Anne Schuchat: Let me start with the general and Argentina question and let others chime in. Generally the way that we have been planning the vaccine procurement has incorporated a lot of possibilities. As you all know, influenza vaccine production can be quite unpredictable. For our planning assumptions we're really on track and not concerned about not meeting expectations. Knowing that things can change further. In terms of Argentina, we're aware, you know there's been a lot of media coverage of Argentina and there are different conditions being reported for different parts of the country. The 2009 H1N1 influenza strain has been the majority of the viral isolates that have been based on the virological surveillance that we have been able to see. We do have people in the field who have described some intensive care units with the numbers of ill younger people and others that aren't over capacity. Like here in the United States, we had a lot of variability from area to area, sometimes within a state, of how much disease there was. Like a popcorn pattern where disease was occurring. In Argentina, I think that's likely a similar situation. I think I may have answered your questions. Do you have a follow-up?
Dave Daigle: Dr. Goodman, or Dr. Gellin, did you want to add anything?
Bruce Gellin: This is Bruce Gellin. I think Anne handled that unless Maggie has an additional follow-up.
Maggie Fox: No, that takes care of it.
Dave Daigle: The next question, please.
Operator: Our next question comes from Betsy McKay from "the Wall Street Journal."
Betsy McKay: Hi, thanks. I have a vaccine question and a follow-up about Argentina. The vaccine question is, could you go through what the factors are, scientific, political or otherwise, that are going to be needed to be considered to use the adjuvant for the vaccine and when you expect to make a decision whether or not adjuvant will be used? The Argentina question was -- I want to ask this report about a nationwide animal health emergency -- this goes back to the question that there's been findings that the virus has been in a pig herd and may have been passed from humans. How concerned are you about that possible mutation?
Anne Schuchat: Let me provide a little bit of information here. We know that influenza viruses can go from pigs to people and from people to pigs. We work closely with partners in agriculture here in the U.S. and around the world to protect both species basically. I don't have specifics about the animal situation in Argentina and it may be better to get information from our agricultural colleagues at the USDA or the OIE, which is sort of the international animal equivalent of the World Health Organization. But we -- I'm trying to remember the other part of your question -- I think, you know, it's important to recognize that we want vaccines that will give a good immune response and there have been some times for instance with the H5N1 virus, where it was only when adjuvant was added that you really were able to get a pretty good immune response. All things being equal, an unadjuvanted vaccine is often just fine in terms of giving protection against influenza virus. So, there issues in terms of whether one will get dose bearing, more bang for your buck out of a certain amount of antigen. That's often a factor that's considered with adjuvant. And adjuvants are sometimes considered in order to broaden the immune response. If there's a change in the strain and there's not a good vaccine match, sometimes an adjuvant will provide broader coverage. At this point, you know, the U.S. has made plans to procure both antigen and adjuvant. And my partner can share with you some of the plans of how these things will be tested in terms of with and without adjuvant. But, the factors really are issues of benefits and safety and supply. Jesse, did you want to expand on that?
Jesse Goodman: No, I think, I would add that it's critical to mention that we don't know yet with this vaccine, either how the nonadjuvanted vaccine will behave or what the potential benefits of an adjuvant may be. So, that in the early clinical trials, including with our colleagues at NIH and the companies, the intent is to evaluate both the nonadjuvanted vaccines and adjuvant vaccines. We don't have reasons to think the nonadjuvented licensed products would be not immunogenic here. There are H1N1 viruses in every years vaccine. But this is a unique virus, so we want to confirm that. With respect to the adjuvants, these novel [unintelligible] adjuvants they're not currently licensed in the U.S. But we want them on the table incase there are issues where they might be needed to protect people in this country. That's the reason to include them in the studies as well as to be prepared in the stockpile in case we need them.
Bruce Gellin: This is Bruce Gellin. Let me add to that. It follows on the theme that Anne laid out early, there's a lot of uncertainties. You want to have as much flexibility as possible. We have procured both ingredients -- the antigen and the adjuvant. Having both allows us that flexibility and therefore, make subsequent decisions if things change.
Anne Schuchat: Okay. Next question, please.
Operator: Thank you, our next question comes from Robert Lowes from Medscape medical news. You may ask your question.
Robert : This is a question for anyone who wants to answer it. But, there's been some concern that our reliance on vaccine manufacturers in foreign countries leave us vulnerable -- that they would supply their own countries in the event of a pandemic, ongoing pandemic, and that supplies that we counted on from them might not come to us, are you concerned about that?
Anne Schuchat: Yes. Thank you for that question. We have heard those concerns being voiced. You know, in terms of our own planning and arrangements we have with manufacturers, that is not one of our current concerns. Next question, please.
Operator: Thank you, our next question comes from Miriam Falco from CNN medical. You may ask your question.
CNN: Hi. Thank you for taking these questions. I kind of know the answer to this, but I want to ask it anyway. Given the fact that you don't know when a vaccine will be ready, people are left to contend with the regular flu, what do you tell women who are pregnant right now, or people who don't want to get sick -- what can they do? Also, how -- people may be concerned getting one flu shot for the seasonal flu and another one that's not been out there very long, what can you tell folks about that to alleviate any kind of fears?
Anne Schuchat: Thank you for that question. Pregnant women, for a long time, we have known that pregnant women are at risk of complications from influenza, that's a real challenge. The health of women and their babies is important to everyone. A couple of key issues for pregnant women, we have seen with this virus, worse complications and severe infections in pregnant women and we're urging women who are pregnant who develop fever or respiratory symptoms to seek care promptly. We think that early antiviral medicines for this women are really important. I know that many pregnant women don't want to take anything while they're pregnant. This is a situation where you need to be more worried about your health and the baby's health. The prompt recognition of symptoms, like fever and cough, seeing their doctor or health care provider and urging treatment. In terms of prevention, there's a lot all of us can do, of course we talked about trying to protect others from infection by washing our hands or covering our coughs and sneeze. Staying home when you're ill. Keeping your kids home when they are ill. There are also recommendations for vaccines, again, pregnant women are recommended to get an influenza vaccine and I strongly urge to get the seasonal influenza vaccine, when it comes available. We're expecting pregnant women to get the H1N1 vaccine against this new virus. I think that's really going to be important. For people who are at high risk like pregnant women, planning to receive both vaccines is probably the right way to go. That risk of complication from any influenza is a challenge that we can potentially prevent. In terms of specific recommendations for the 2009 H1N1 vaccine, as I mentioned our Advisory Committee on Immunization Practices is going to convene later this month specifically to make recommendations on target groups who ought to receive this new vaccine we make recommendations for the seasonal flu every year. We don't expect those recommendations to change. We do expect people to get their seasonal vaccine and there's a number of groups recommended for that. Next question?
Mike Stobbe, Associated Press: Thank you. Thanks for taking the question. I have three, doctor, first, you're expecting an increase in influenza this fall, perhaps earlier than normal, I was wondering if you could explain more what you're expecting and why you're expecting. This virus seems to be doing better in heat and humidity than seasonal flu viruses, do we know why it's behaving that way? The last, the WHO said this week, they're going to stop releasing case counts and I think CDC said that might come someday, too. The public looks to public authorities on how outbreaks are doing. So I was wondering what CDC's plans were for case counts in the fall.
Anne Schuchat: Great, thanks, Mike, for those questions. You know, I am expecting, but as we always say, we never can predict influenza. I'm giving our best prediction possible with an unpredictable scenario. We're expecting an increase in influenza or respiratory illness, that could be earlier than what we see with seasonal influenza. In the fall, there's an increase in season influenza. Every year in the fall, there's an increase in respiratory illness, not just influenza, when kids go back to school and people get back together and the germs getting shared. Now, this year, of course, we have been seeing this 2009 H1N1 influenza virus circulating in the summer months. We have seen it in camps and military units and so forth. I'm expecting when school re-opens and kids are all back together, in some communities at least we may see an increase. Not to say that it's necessarily going to happen. It's the kind of thing that we want to be ready for and not surprised by. When I mentioned the heat and humidity, the issue, I think, is twofold. This is a new virus that we don't think there's general population immunity to, it may be this virus is transmitted the same as seasonal influenza virus in the summer months, there's more people out there who are susceptible to it so that when it's transmitted, perhaps there are more people who are vulnerable to getting sick. There's no data to suggest that there are better transmission properties of this virus in terms of heat and humidity. I imagine it's a susceptibility problem. I don't have any data behind the other feature. The other question that you had was about the WHO case count news. And you're right. We have been talking about that for some time, that while we were giving the laboratory confirmed cases and we have been posting onto the websites, we're not sure it's useful as other ways of tracking influenza. We've known that for very common conditions like seasonal influenza, individual case reporting is not the most effective public health reporting tool. Recognizing the challenges of keeping up with it is quite different in different circumstances. We're not surprised by WHO making that call and we're expecting within the next few weeks to shift around a little bit the way we report to you what's going on. We expect to be stopping the individual case counts, laboratory case counts that we have been sharing with you and share with you more of our traditional reporting with some enhancements and recognition of the properties of this virus. Look to our website, www.cdc.gov. And something called FluView and that has on it quite a lot of details for those of you following carefully. Some of the maps that we see, information from the virologicals surveillance that we do, information on mortality of children, something that we have been tracking actively for many years now. And there will probably be some new data sources showing up on the new flu view showing up in the several weeks. We agree that idea of individual case counting is probably not the best way to track what's going on. This virus is in almost every country right now. Next question.
Operator: Our next question comes from Maryn McKenna with CIDRAP News, you may ask your question.
Maryn McKenna: Hi, thanks for doing this. I wanted to see if we can get a little more grainularity about a vaccine time line, particularly with respect to adjuvant. Dr. Goodman said earlier, a clinical trial -- collecting clinical trial data for a nonadjuvanted vaccine will take about a month given there's a blood draw at 21 days. Could you talk a bit about how adding adjuvant products into that is going to delay the time line, if at all, given that the adjuvants being looked at here are currently licensed in the United States, as you said at VERBPAC meetings in the past couple of years, any vaccine will be have to be licensed at a particular dosage not just as a bulk add in.
Anne Schuchat: Let me make a couple of comments and then let Dr. Goodman fill in the more detailed answer. You know, my understanding is that there'll be simultaneous studies of vaccines with and without adjuvants so that you wouldn't have to factor in a long sequential process before results from that would be available. I think that the expectation we'd all had -- if we end up using adjuvant they would be used under an emergency use authorization rather than through a licensure pathway -- let me let Dr. Goodman give you more details on that.
Jesse Goodman: That's correct. The anticipation is first of all, that adjuvant use would be contingent upon showing that it was needed or clearly beneficial in these studies and they are being done in a way to try to get data but with or without adjuvant as quickly as possible. I just want to correct the impression that we might feel that we would substantive data within a month. What I was saying is that the first blood draw after an initial immunization might -- would -- or a blood draw would be informative might be around 21 days and the samples need to be processed and we're thinking in terms of likelihood, a couple of months' time frame from the initiation of clinical trials. We're working to get everything as quickly as possible. We do, as I mentioned, have high expectation that the current license formulations of vaccines will be immunogenic, immunogenic and safe at standard doses, but we also need the data on that. We're trying to get the data as quickly as possible. If adjuvants were to be very helpful or needed, we are also reviewing all of the safety and other information on those products from the manufacturers and also in collaboration with sister agencies around the world so that we'll be able to make the best risk/benefit assessment at that time.
Bruce Gellin: And this is Bruce. For those, there are many questions like this. It might be worth it, or thinking about participating at the VERPAC meeting. I'm sure there will be a webcast, or some way that you can see that, that's where there will be many, many more details than we can get into now so to those this have a particular interest of this arm of the study versus that arm of the study or this company and that company, that's the place you're going to get much more information that we can provide.
Jesse Goodman: I think you'll get a feeling for the fact that we're proceeding on multiple fronts and we're trying to get the right balance of getting critically important data as quickly as possible such as, how this virus will behave in a normal license vaccine and getting the information to be prepared for the possibility that it may not perform to the way we want.
Anne Schuchat: Okay, great. Our next question.
Operator: Thank you. Our next question comes from David Brown with the Washington Post.
David Brown: Yes, thanks. I have a couple. Can you say a little bit about how -- in how many places the clinical testing is going to occur? And I was under the impression that it's actually begun, that some people had gotten injections. And my other question is the liability for, you know, untoward effects from this going to be assumed by the manufacturers as it is with seasonal vaccines or even if it's an unadjuvanted product, is the federal government going to, you know, assume some liability because it's a special thing that you all have ordered up?
Anne Schuchat: Let me say one or two things and then let Dr. Goodman expand on the clinical trials. The NIH-funded clinical trials or overseen clinical trials are going to be done through their vaccine and treatment evaluation units, on their website, you know, they list all of those. I think the manufacturer-conducted trials will be done elsewhere. Dr. Goodman can expand on that. The liability issue is expected to be covered through the PREP Act, which essentially covers all the way from the manufacturer through to the point of delivery of a vaccine such as this versus a pandemic or other similar kind of threats so that we're not expecting the usual kind of liability issue to emerge. Let me let Dr. Goodman to expand on that and then Dr. Gellin may want to expand on the PREP Act a little bit.
Jesse Goodman: Yes, Anne, I think you explained it quite well. The NIH has several clinical trials sites they're planning to employ and they have a sequence of studies. I believe those will be discussed in more details at the advisory committee meeting, as Bruce mentioned, next week and we, the manufacturers and NIH have been working together to plan these studies so that even though each of the manufacturers is also going to be doing studies and submitting data in real time to FDA, we're trying to integrate this as an entire program and to be sure we answer as many questions as we can. We view this important from a public health point of view that there's value in having studies both being performed by the manufacturers and through NIH.
Anne Schuchat: Okay, Bruce, did you want to expand on the PREP act or was that okay?
Bruce Gellin: I think that's it. We acknowledged, when we were doing this with the bird flu situation, that this was going to be a potential barrier of a development of vaccines and it was for that reason the PREP act was developed.
Anne Schuchat: Great. Could we have the next question, please?
Operator: Our next question comes from Marrecca Fiore of Fox News Channel. You may ask your question.
Marrecca Fiore: Hi, I actually have three questions. My first, I was wondering if you could elaborate a little bit more about what your plan is for school districts, we're about six weeks away from school starting, as you stated earlier, viruses tend to spread quickly in school districts, especially in urban areas where schools are often overcrowded. My second question, as far as a vaccine goes, health experts when they develop a vaccine say on in a good year, we can expect something that's about 70% to 90% effective. I'm wondering with the H1N1 virus, because we still know so very little about it and how it's mutating, what kind of success rate can we expect from a vaccine? And, my final question is, I know that we're noticing at least from our readership, I work for the Web site, you know, people don't seem as interested in swine flu as they once were, I'm wondering how you think that public apathy could be a detriment to fighting this virus?
Anne Schuchat: I'll probably take your questions in a reverse order. The complacency is a major concern. You know, I think that we're taking this virus very seriously. Seasonal influenza is also serious but this virus is a new one on top of that and we're making special efforts to be ready. I think it's very important for the public to be thinking ahead and making sure they have steps ready to go, should a family member become ill, should their workplace or school go under unusual circumstances like closure or telecommuting recommendations. And we don't know that those events are going to happen, but it's a lot better to think them through as a family or as a community ahead of time. In terms of the expected results, in terms of the effectiveness, as you say, the seasonal influenza vaccine has a range of effectiveness, depending on year, depending on how closely the strain matches the strains that are circulating and more importantly, depending on the host. So the vaccine is not as effective in the imunocomprosmised as it is in healthier people. Fortunately in children the vaccine is typically more effective than in the frail, elderly, where the seasonal flu vaccine doesn't work quite an as well. Still we do think that vaccine is the best protection against seasonal influenza and of course that we're making great efforts to have a vaccine ready for this H1N1 virus.
We do not know how effective an H1N1 vaccine will be in different populations. Those are the kinds of things that get looked at in terms of the immune response in the studies Dr. Goodman was talking about but I also want to let you know we'll be tracking the effectiveness of the vaccine after it's been used to understand how well it did - did it do as well as predicted, better than predicted or not as well as predicted. So those are the kinds of things that we don't necessarily get the information ahead of time we usually have to get that information during the season. The last question was, what our plans are with school districts, parents and teachers and so forth. I want to say that at the national and state level, there's very close collaboration right now between health and public health and education, our secretary of department of health and human services is working in close partnership with the secretary of education, and last week at the influenza summit, we had leaders from every state, education and health sector, working together, trying to think through the issues that we face. We'll be updating our guidance on schools and other similar institutions in partnership with education, trying to use the science of what we learned about how effective the interventions that we used, what were their costs and what were their unintended consequences. We have some general philosophies and principles that the best place for healthy kids is in school, where they can learn, where they can be educated, and where many of them get breakfast and lunch and can be nourished as well as learn. We also know that sick kid with respiratory illnesses like the influenza are better off at home where they're being cared for and not spreading their illness to others. We're trying to make sure we have strong plans in place for communication and preparedness, thinking through issues such as vaccination associated with schools and that we're working together at that local or state level, where everything's just a bit different with schools. So the national level is trying to provide guidance but we're strongly urging the local and state levels to work across sectors.
Dave Daigle: We have time for two more questions.
Operator: The next question comes from Tracy Potts with NBC, you may ask your question. Tracy, your line is open. You may ask your question.
Operator: Okay, we'll go on to the next question from Tom Randall with Bloomberg News.
Tom Randall: I have a couple of questions. First, going back to vaccine production; I have spoken to about three companies so far that have said yields from egg production have been very low and I sense from them that if they are not able to boost yields with future tests that it could become a real problem. I'm wondering if you can you specifically address this issue of yields and quantify these yields compared to historical yields? Second if you could just briefly address the speed at which this pandemic has taken root around the world and how that kind of compares with past pandemics and what they might tell us about this pandemic.
Anne Schuchat: You know, the yields -- what we have heard about yields is consistent with the way we were planning, so while I think, you have directly spoken with companies about what they're seeing, we incorporated some of those kinds of expectations into our planning, so far, we haven't heard news that has changed our expectations for vaccine availability in the fall. As you know and Dr. Goodman certainly knows, manufacturing is a challenging business and there can be additional surprises. Based on what has been described to us so far, it's within the range of our planning assumptions but that doesn't mean we won't have more surprises.
The speed of the pandemic, of course today is very different from 1918 or even 1968. We have seen this virus reach nearly every country in a matters of weeks and months rather than years. So I think the issue of how quickly it's spreading is a relative term, we also know that we have a lot more tools at our disposable today than they had in 1918. So we're using that same speed of communication and information to really challenge, to be ready for this virus in terms of the scientific infrastructure that's responding, you know the virus as been shared all over the place with laboratories researchers who can develop better responses to it and learn more about it. And the communication and transparency among countries has really been a help. We knew about this a lot earlier than we might have if we didn't have the investments that we have in the preparedness arena.
Dave Daigle: Thank you. Shirley, our last one.
Operator: Our last question come from Donna Young of BioWorld Today, you may ask your question.
Donna Young: Hi, thank you for taking my question. I wanted you to elaborate a little bit more about that AP story that came out yesterday that caused a lot of panic over whether there would be vaccines more as you said, just that simply it's not a concern. Can you give more assurances as to why it's not a concern, give a little more detail on how the contracts are backed up and just explain that a little bit more. Please. Thank you.
Anne Schuchat: Yeah, we have plans in place with five companies, their manufacturing enterprises are in different locations, but based on the agreements that we have and the discussions we have had, these concerns that have been raised, I think really, in the media have not been part of the dialogue. We know that many countries did take steps to prepare for this kind of problem and we haven't gotten information that makes us question our -- the supply that we have been promised.
Anne Schuchat: So, think that's the end of the session, thanks to everyone who's been listening and the reporters who help us get the story out to others.
Dave Daigle: Shirley, thank you for your help.
Operator: you're welcome. We thank you for your participation. At this time, you may disconnect your line.
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