CDC Telebriefing on Investigation of Human Cases of H1N1 Flu
Dave Daigle: Thank you Angie, this is Dave Daigle from CDC Media Relations.
Today, we'll update the emergency response of the novel H1N1 flu outbreak with Dr. Anne Schuchat, our director of the National Center of Immunization and Respiratory Diseases. She will provide a short update and then take questions.
Anne Schuchat: Good afternoon. We're roughly a month into our emergency response to this new virus, and I think it's a good time to stop and take stock. Confirmed cases continue to rise here in the U.S. and around the world, and we've had this initial focus on cases and responding to illness and understanding this very new virus and how it behaves in our population. I think we're at a transition point where we're entering an area of new focus and new priorities. We really are on a fast track over the next eight to ten weeks to learn as much as we can as this virus heads to the southern hemisphere and to strengthen our planning for this surge of illness that we expect to experience here in the fall. Today, the World Health Organization is announcing that the global case count is 12,954 cases in 46 countries. And, of course, here in the United States, we are contributing very much to that world case count. Our count today is 6,764 probable and confirmed cases in 48 states and the District of Columbia. There have been more than 300 hospitalizations, and we have ten deaths reported on our website although you may have heard some reports from additional sites that haven’tyet made our system. In this period of transition, we continue to update guidance to make sure that information is available. Over the weekend, we've posted updated guidance on safe mask and respirator use and also on addressing this novel virus in correctional and detention facilities. This guidance, like our earlier interim guidance, is based on what we know now and the best science available as well as the situation on the ground. There are many areas where we wish we had more science available and we're continuing to really try to fill some of those gaps. In terms of the weeks ahead, there are a couple of areas that will be under intense pressure. Understanding what this virus does in populations that are just entering the influenza season, the winter months in the southern hemisphere will be very important, our different populations at risk of illness, will the virus change and become more resistant or more severe or transmissible. What will be experienced in populations that don't have a strong health infrastructure as we do here in the United States. A second area of focus is preparing for the fall. Based on what we've learned from our surveillance experience, the laboratory testing and surge that the health care system and public health system has gone through, how can we best prepare to handle an influenza season that's normal and a potential for this new virus to cause illness or problems on top of the regular seasonal flu problems. We'll also be working across government in the early steps of development of a vaccine, and as you heard on Friday, Secretary Sebelius announced a commitment for a vaccine and pandemic stockpile of that vaccine. So there’ll be quite a bit of planning will be around the potential development of a vaccine for use and if it were to be used, what sorts of steps would be needed to actually manage an immunization campaign. Those are the kinds of things we'll be turning our attention to while we continue to support the state and local areas around the countries for whom this problem has not yet ended. In the country as a whole, the influenza-like illness patterns are starting to decrease. There are still focal areas where ongoing cases and new hospital consolidations are a daily problem but in many parts of the country influenza-like illness is returning back down to the levels that we would expect for this time of year. We need to stay ready. There may be new clusters or new communities that haven't seen the virus yet this spring, which may have problems, but much of our attention is focusing on your hemisphere and the preparations for very intense experience in the fall. So with that, I would be happy to answer questions.
Dave Daigle: Thank you, doctor. Angie, we’ll take the first question, please.
Operator: Thank you. David Brown of "The Washington Post", your line is open.
David Brown: Yes. Thank you very much. Doctor, I'm wondering what, if any, studies are being done on the half of the people who are hospitalized, most of them young adults, who have no underlying illness, predisposing them for a serious case of influenza, because it seems to me it's kinds of a half glass half full/half empty, pretty shocking in some sense that there are people who are in their teens and 20s who end up on ventilators with no obvious reason why they should, you know, have such a severe case. So are your all doing things to try to see if they have certain genetic characteristics that might predispose them for a serious illness?
Anne Schuchat: There are definitely projects ongoing to look at hospitalized patients, to better characterize what, if any, underlying illnesses they have, to understand their clinical patterns and to really identify risk factors that may not be evident. I think it's important to note that even seasonal influenza can cause severe complications in otherwise healthy people. We have been carrying out active reporting of pediatric deaths around the country and every year between 50 and 100 or so children die from influenza. Many of whom don't have underlying diseases. The very vast majority of deaths that occur in influenza are in seniors and majority of hospitalizations are in people with underlying diseases. Even totally healthy young children and teens can die from this infection, just the seasonal flu. The genetics of risk is an interesting concern. I'm not certain whether we have studies ongoing. That's been an issue that's been of interest even with seasonal influenza. So I can't really speak to that in particular.
Dave Daigle: Thank you, David. Next question, please.
Operator: Thank you. As a reminder, if you would like to ask a question, please press star 1. Betsy McKay, “The Wall Street Journal,” your line is open.
Betsy McKay: Doctor, a couple of questions. You were mentioning that influenza-like illness levels are returning back to levels we expect to see for this time of year. So does that mean that -- is that regular seasonal influenza or does that mean that levels of novel H1N1 are starting to decrease, because the numbers we're seeing every day would suggest the opposite. I think my ultimate question is what do you expect to happen as the warmer weather comes across the country? Is this going to peter out for awhile or do you think it's going to continue to build, the number of cases over the summer?
Anne Schuchat: When we overlay our virologic surveillance on influenza-like illness, what we see is the vast majority of influenza-like illness that has a viral isolate associated with it. Right now that's the novel H1N1 virus. A few weeks ago, there was a bit more of the seasonal flu still circulating, but right now,almost all the positives we have is this novel H1N1 virus. When we look more broadly at the influenza-like illness trends, while almost all of the influenza-like illnesses this new virus, the actual percent of visits that are influenza-like visit are going down in most regions of the country. So we can see that overall we're below -- you know, we were over baseline for this time of year, which is really extraordinary for the past several weeks. And now we're down below the baseline again. With our nine regions of the country, I think there's only one that is still at an elevated level. Actually two levels, region one and two are still a bit higher than you would expect for this time of year. The others are all on the downswing. So that your question gets to of the viruses that are circulating, is this novel H1N1 the major culprit? Yes. But how much disease is circulating? Probably less now than a week ago.
Dave Daigle: Thank you. Next question, please.
Operator: Thank you. Steve Sternberg of "USA Today," your line is open.
Steve Sternberg: Thank you very much. I wanted to ask about how you would track flu in the southern hemisphere this winter.
Anne Schuchat: Thank you. You know, there are several important aspects of tracking influenza in the southern hemisphere. Probably the most important aspect is to understand the virus. This requires laboratory testing of people with influenza symptoms or respiratory conditions and it requires an infrastructure that can do that testing and the special test kits that we have developed and distributed. There's a number of places in the southern hemisphere that regularly carry out influenza surveillance and we want to make sure those laboratories can test for this new virus on top of their regular viruses. We also are interested in the epidemiologic characteristics of the disease. Does this virus cause long hospitalizations with pneumonia? Is there a secondary bacterial pneumonia occurring or is this a primarily viral type picture? Which populations are at higher risk? Children or adults with or without underlying diseases? What are the circumstances? Are there outbreaks in schools or institutions like we saw here with the school outbreaks, or is this more of a hospital transmitted affection or strictly in the community? Those are the kind of issues we'll work on. CDC works together with the World Health Organization and many ministries of health around the world to strengthen infectious disease surveillance, laboratory capacity and field investigation, and we're in the process of partnering with Pan-American Health Organization and a number of partners in developing active plans for the southern hemisphere.
Dave Daigle: Thank you, Steve. Next question, please, Angie.
Operator: John Cohen from "Science" magazine.
John Cohen: I have two quick ones. You're suggesting that the outbreak may have peaked in the United States? And the second one, the decision for purchase of ingredients for 20 million people to receive vaccine, when do you plan to make a decision for the rest of the U.S. population?
Anne Schuchat: The question about has the virus peaked is a complex one. I like to use the analogy of weather and while most of the country may be entering the warmer months or even summer, cold fronts could happen in any particular location. So, we know that diseases are still very active in New York City and a few other parts of the country and they may not feel that this condition has peaked. We don't know whether the warming up in a lot of areas is permanent or they might have some more disease to come. Our national statistics and most of our regional statistics suggest that we may have passed the peak here for this time of year. We're also thinking that the later we go, the more of the warm summer months ahead may give us a little bit of respite. The question about the decision to vaccinate is important. We do try to separate the question about the initial steps of vaccine development, later steps of vaccine production, and further steps that might involve a decision to vaccinate some or all of the population. There needs to be an evidence-base and careful deliberation for each of theses steps, and we don't intend to make a decision about immunization until, as late as possible. The idea would be to learn all that we can from the southern hemisphere experience about the ongoing severity and problems associated with this virus. And to learn all we can from the clinical pilot lots that are developed against this virus, to understand whether a vaccine that is tested is even safe and beneficial and to take the information of that potential risk, potential benefits and the potential value of an immunization program for the summer for all of the country we'll make that decision in probably late summer or early fall.
Dave Daigle: Thank you, John. Next question.
Operator: Steven Reinberg from "Health Day." Your line is open.
Steven Reinberg: Did I hear you correctly you expect the virus to surge in the Fall? And if that's so, do you expect to it be worse than it has been?
Anne Schuchat: Let me clarify. We do expect seasonal influenza to return next fall or winter. Every year we see many strains of influenza circulate and the timing of the beginning of illness can vary from early to late fall to winter, depending on the part of the country. So that is a given. We're certain we'll continue to have a seasonal problem with influenza. It is very possible that this virus will continue to circulate and cause illness again next fall or winter. Whether it will cause more illness than it's been causing recently, whether it will dominate among the seasonal flu viruses or whether it will really disappear is not predictable right now. We're mindful of the past that pandemics of influenza have sometimes come in waves and the very severe 1918 pandemic had a moderate or mild herald wave in the spring and a much more severe second wave in the fall. So that really terrible experience of 1918 is in our minds. But I can't tell you whether this virus will cause a lot of disease, some disease or no disease here in the northern hemisphere next season. It's really being prepared for the possibility that it will, that we're focusing on right now.
Dave Daigle: Thank you very much. Next question, please.
Operator: Helen Branswell from "Canadian Press," your line is open.
Helen Branswell: Doctor, I was wonder if you could tell us about the susceptibility testing.Are all the viruses fully susceptible to Osteltamavir and Zanamavir or have any been thought of having reduced susceptibility to those drugs?
Anne Schuchat: The novel H1N1 viruses that we have tested are all susceptible. I'm not aware of other labs that have found differences. I checked with people today about whether there were any hints of problems and was told no. So my latest information is that we have not detected any problems with Osteltamavir and Zanamavir resistance in this novel H1N1 virus. We are very aware that resistance has emerged in the seasonal H1N1 viruses to the point where virtually all of them are now resistant to Osteltamavir. So we feel it's very important to keep tracking viruses and not assume this novel H1N1 virus will always be sensitive. But for the time being, we continue to have good news on that front from our laboratory.
Dave Daigle: Thank you, Helen. Next question, operator.
Operator: Mike Stobbe from the "Associated Press," your line is open.
Mike Stobbe: Similar I guess to Steve's question. I was wondering about surveillance in the southern hemisphere. You mentioned you're working with PAHO but that season’s about upon us. Do you have any more detail you can give us in which countries surveillance will be taking place? Also, we've talked about a vaccine against the novel influenza virus for the United States, but what about some of the southern hemispheres? Is that season just too close and we could, you all could ever pull that off?
Anne Schuchat: Let me take the questions in reverse. The steps involved with developing a vaccine are numerous, and there isn't enough time to develop and produce a vaccine before the southern hemisphere flu season is upon us. So, unfortunately, the timing of the new virus' emergence and detection is such that we don't think we’ll be able to get vaccine available before the flu season peaks in the south. On the other hand, the World Health Organization is working with manufacturers and developing countries and such to try to address the eventual need of their global community with vaccine development. Your other question was more detailed about how we will be working with the southern hemisphere, and for instance which countries. I want to say that the CDC is part of the W.H.O.'s global influenza surveillance network and of course we also developed these reagents that permit testing against the new virus and so we have shifted our test kits out to more than 100 countries, I believe. I'm looking for the numbers, but I can't find them. We really widely ship kits out so other countries will be able to identify this virus and with technical assistance we hope that the laboratory testing can be added to the influenza laboratories in most countries where they exist. So that will be a primary way that we try to support southern hemisphere work in both provision of these important reagents and the technical assistance to make sure that the testing can go forward. In addition to that, we do expect some active efforts to look at clinical disease and this is really building on some efforts that the CDC has had for several years where we've been focusing on respiratory illness in a number of countries. The actual details of which countries will be major focus of our effort, I don't have yet. That's the kind of information we would like to share with you in a future briefing.
Dave Daigle: Thank you, Mike. Next question, please.
Operator: Thank you. Your line is open.
Kafi Drexel: A couple parts to this question. First of all, you mentioned that there's some regions of the country that are still seeing higher increased amounts of activity. Am I correct to say that obviously New York is one of those areas. And can you comment on what other regions? Also, more specifically for New York, in your surveillance, how do you guys have been doing on some things more specifically on the ground looking at the borough of Queens which seems to be an epicenter this was activity to figure out why that is, and also since if it does seem to be an epicenter of activity why it hasn't trickled out more into the larger community and in an area where people commute by buses, subways, there's a lot of foot contact, et cetera. So, there's that part of the question. The other part is just more on how much longer given the way that flu seasons behave you expect for this to act and we are getting into the warmer months here already, so what kind of impact that can have on activity here as well.
Anne Schuchat: Thank you. New York is part of region two, which has New Jersey and New York in it, and that is one of the two regions that still has influenza-like illness that's at a higher level than earlier weeks. The second region that still has influenza-like illness at the higher level is region one, which is essentially New England, it's Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island and Vermont. So the New York/New Jersey and New England areas are still above that baseline whereas the other regions are on the downswing. Your second question was whether we're on the ground in New York and I need to emphasize that the New York City health department has a terrific team that's very actively in the lead and responding to the situation there. CDC has provided some assistance to the New York City health department in looking further into the situation across the city. So, I will leave it to the New York authorities to report on what they are learning in that very active investigation. Your third question was about how much longer do we expect this virus to circulate and cause illness here in the U.S. or perhaps in the New York City area, and I think this is one of those very challenging questions. Sometimes influenza continues to cause illness in the summer. There can be outbreaks in summer camps with regular seasonal influenza virus. It's the function of the survivability of the virus in certain circumstances, the population characteristics, and really how probably some things we don't know, measure. So I can’t tell you that New York will not see ongoing cases over the weeks and months ahead. In general, we don't see much influenza in the Summer months, and we are all hoping that that will be the case. But that's one of the reasons we're turning our attention to southern hemisphere and also to preparing for the fall, but as you know, right there in New York, it's a very active investigation and response with you had hospitalizations that are challenging and so we know things are not finished up for the season yet in New York.
Dave Daigle: Thank you. Angie, we have time for one last question, please.
Operator: Thank you, Lisa from "Greenwich Times," your line is open.
Lisa Chamoff: Thanks for speaking with us today. My question focuses on school closures, and I know many schools have been applying, the most recent CDC recommendations not to close school unless there's a magnitude of absenteeism that interferes with activities. I'm wondering given the research you've done recently and especially in region one and two there's a lot of emerging new cases. Any updated guidelines or advice on whether schools should close if they are seeing an uptick in cases and is there a point when closing the school would, you know, stop any, any increased transmission?
Anne Schuchat: The school guidance that CDC has issued has not been updated since, I believe, May 5th or so, and that guidance, either that interim guidance really tried to incorporate what we had learned about this virus, its severity, and transmissibility in contrast to some of the more severe pandemic strains that we studied from the past like the 1918 strain. And that guidance continues to be that school dismissal for the purposes of slowing transmission was not recommended for this virus. We had initially recommended it at the beginning of the response. Instead, we suggested that local authorities make these decisions and then a factor for dismissals might be when the absentee rate was such among students or staff that the school couldn't really function well. The issues that local authority will take into account in addition to the severity of the virus which is what we were trying to help with, would be multiple, you know, the size and staffing at the school, what services the students will have if they aren't there in class, where you are in the school calendar, what are the competing needs and balance the value of being in school with the potential protection that might be afforded by not being in school. The focus of our guidance and most of the local authority's guidance has been that if you are in school we think it's important that those who are ill stay home and that, you know, people recover from their illnesses at home. That children who are found to be ill at school be sent home so that they can be taken care of and not, you know, have to beat the school environment. So we, our current guidance continues to be school dismissals aren't recommended for the purpose of slowing transmission but may be needed based on local decision making because of the functioning of the school.
Dave Daigle: I think we can take one more.
Operator: Thank you. Thank you. Jennifer Corbett of "Dow Jones."
Jennifer Corbett: I had a question on the timing of the decrease that you're seeing in most regions outside of New England. I mean most recent figures I have are for the week ending May 16th, but I didn't know if you were looking a little bit into last week also.
Anne Schuchat: Yeah. We have a little bit more than the week of May 16th. In our reporting, you know, going through the May 26th reports I'm looking at have some updates on that. But I think an important point I neglected to say in my opening statement was, you know, we've just had a three-day weekend. Most of the public health departments and laboratories were not operating, and the CDC as well --we're not operating on a 24/7 way that we've been operating for the past month and it may be that we see a surge in case count from the states or from our own lab here in the days ahead. So important to recognize that while we had moved from weekly reporting to daily reporting for our influenza-like illness and our laboratory results, some people might have gotten their first day off in a month this weekend, so I think we'll need to see what happens over the next couple of days in terms of some of the predictions I was making.
Dave Daigle: So, thank you very much. This will conclude our briefing. Thanks all for joining us.