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Transcript of virtual press conference on seasonal flu in the northern hemisphere

Thursday 2 October 2008


Gregory Hartl: Thank you very much Arkadin. Just to remind that you will be able to ask questions afterwards and there is a system for queuing up for your questions which Arkadin will explain. I would now like to introduce Dr Keiji Fukuda. He is the Head of our Global Influenza Programme here at WHO headquarters. And now Dr Fukuda.

Dr Keiji Fukuda: Thank you Gregory. Hello everyone, I'm Keiji Fukuda, as Gregory mentioned, I'm head of the Global Influenza Programme at WHO headquarters. And I want to thank you for joining. Given that we are at the start of the northern hemisphere influenza season and this is the time when people really ought to think about getting vaccinated for influenza, I thought it would be useful to have a talk today about influenza and why this is a disease worth preventing and also a bit about what we know - and don't know - about this upcoming seasonal influenza in the northern hemisphere.

And then afterwards, we'll throw it open for questions and we'll take them one by one. So first I wanted to begin by acknowledging that the news & concerns about influenza over the past few years really have been dominated by the avian influenza (the H5N1virus) and also concerns about the pandemic influenza. Both of these things of course are understandable and of critical importance given what we've gone through in the past few years but I am concerned that awareness about seasonal influenza may have dropped off as we've gone through this couple of seasons and WHO would very much like to make sure that people understand about this form of influenza for a couple of reasons. First, it's by far the most common form of influenza -- hundreds of millions of people get infected every year. It's a disease which kills up to about 500 thousand people worldwide and it's also the most preventable form of influenza.

In both the North and Southern hemispheres, it's generally a very good time to talk about it in the Fall because the virus starts circulating in the late Fall and in the Winter. And the Fall period is when people ought to get vaccinated.

Now the first point about influenza is that it is of all infectious diseases, one of most common of the serious infections but it is also one of the infectious diseases which is frequently misunderstood so hopefully, we'll dispel some of the misconceptions today.

Now there are a couple of main reasons why this is such an important disease. The first one is that it is found everywhere. It's an infectious disease which is not restricted to cold parts of the world but you're likely to run into it in the tropics. It's an infection which is not [restricted] to one age group or the another but it can affect anybody in any age group. It's a disease which really spreads easily among people so for example, it can sweep through schools, it can sweep through nursing homes or businesses and towns and the reason why it spreads so easily is that when an infected person coughs and especially if they don't take care to prevent their droplets from going into the air the virus gets into the air and another person breathes it in. So basically, if you breath you are susceptible and can be exposed. Now the second point is that influenza really can cause serious public health and economic problems. So this is true for countries for example when epidemics result in high levels of workers missing their jobs and this absenteeism leads to economic losses. It's true for communities when large numbers of sick people appear at clinics and hospitals and can overwhelm them but mostly and most importantly it's true for individuals and particularly for people who are vulnerable to this infection. So while most people recover from a bout of influenza there are large numbers of people who can be hospitalized from this disease and there are large numbers of people who die from this disease every year.

So if we ask ourselves who are the groups and the people most vulnerable to this, it's fairly clear. These are the elderly people, and they are the group of people who are most likely to die - and the very young - the very young are frequently hospitalized for these respiratory infections. There are people who have weakened or altered immune responses and there are people who have one or several chronic medical conditions. So for example, people who have chronic obstructive pulmonary disease from smoking perhaps, or heart disease, or kidney, things like diabetes or cancer, and people who are taking immuno-therapy for example, these are all people who are highly vulnerable to the more severe effects of influenza. Another important group is pregnant women. Pregnant women are known to have a higher rate of hospitalization when they get infected by this virus.

Now there are several ways that we try to prevent influenza each year. For example, there's often information available from the local health authorities about whether influenza is in the area and it gives you an alert about taking certain actions. We now have better and faster tests than in the past to diagnose infections when you go to a health care clinic and we also have antiviral drugs which act specifically against the influenza virus.

But vaccines are really the single best tool that we have to fight against this infection. Vaccines have been used for more than half a century. And they are known to be safe. Their ability to protect people can be variable and can depend on the age group and it can also depend on how well the viruses in the vaccine match the viruses which are circulating among people. Nonetheless, over the years, and there have been decades of studies - these vaccines have been proven to work over and over again. So the key message here is that the single most important thing that I'm going to say here is that influenza vaccines can protect you, they can protect individuals and they can protect the people around you, including the people that you care most about. This last point is really worth emphasizing. By getting vaccinated, you can help protect your family. If you are a health care professional, you can help protect your patients. Again to stress this last point here, by definition, patients are the most medically vulnerable of all people. We know that health care workers are deeply committed to their care and deeply committed to their patients getting better. By getting vaccinated, health care workers can help reduce the risk of their patients getting worse. It's as simple as that.

Now the best time to get vaccinated is before the influenza season starts up in the area that you live. Some countries have quite large annual vaccination programmes which usually take place at the beginning of the season and WHO is highly supportive of these vaccination programmes. In other countries, influenza vaccines are available but maybe in relatively limited amounts and you really have to seek it out and work a little bit harder. Now, there are some important points about the vaccine itself. As I mention earlier, first, influenza vaccine is considered to be a very safe vaccine. Second, most people are eligible to get vaccine in the form of a shot. However, in some countries, some people can take the vaccine as a nasal spray. Third, this is a vaccine which you have to take every year and the basic reason for this is because the influenza viruses are always changing, they're always mutating and so the immunity that you get from a shot of vaccine can drop over time as the viruses mutate and evolve and change and become different from the viruses which were in the original vaccine.

Now to make sure that the influenza vaccine is kept up to date, WHO makes separate recommendations for vaccines for the NH and for the SH. These recommendations are made by a worldwide group of experts that we bring together and the recommendations for the SH are made in September for the following winter in that hemisphere and they are made in February for the NH for the following winter for that hemisphere. So a few weeks ago we completed making the recommendations for the SH.

Now it's important for you to know that the viruses - there are three viruses contained in the influenza vaccine - this is true both for the nasal spray and for the shot and that these viruses are updated and the number of viruses that can get updated can range from zero to three depending on the year. The number of viruses which are updated simply reflect how much the circulating viruses have changed compared to the year before and whether we have to change the viruses in the vaccine to keep up with those natural changes going on.

So for this upcoming NH season, the vaccine that will be available this year contains 3 updated strains. Now I've seen some reports suggesting that this means that the upcoming season will be unusually severe. And so I want to address this point specifically because it's really a misconception. At this time of the year - before the influenza season has really kicked off - you know, we don't really know how the influenza season is going to go, so for example, this winter it could be mild, it could be severe or it could be anywhere in between. WHO will be monitoring the season closely and we do this with a number of partners in something called the Global Influenza Surveillance Network and this basically consists of 122 National Influenza Centres in 94 countries as well as 4 Collaborating Centres in 4 countries. Now this group of laboratories who work collaboratively together process over 200,000 clinical specimens from ill patients and from those specimens we're really able to monitor the viruses that are circulating that year.

So I think that's about it for what I want to say and what I'd like to do is now turn it over to you for questions:

Gregory Hartl: Arkadin?

Arkadin (the telecoms operator): Thank you. Ladies and gentlemen, we are now starting the Q&A session.

Question 1: Rebecca Smith, Daily Telegraph: Hello, I'd like to ask you about the UK vaccination programme. Currently we don't routinely vaccinate pregnant women or children between the ages of 6 months and 18. Do you think it would be a wise move to include them in our general vaccination programme that includes elderly and risk groups already?

Dr Fukuda: Well generally vaccine recommendations made by a country are made by the national authorities and what happens is that each country assembles the group of experts that will make recommendations for various vaccines for that country and a lot of times these advisory groups like to assess the information available in that country. Now worldwide, if we look at vaccine recommendations, most countries recommend vaccines for elderly people. Then there are some countries which recommend vaccines for other groups such as children, such as pregnant women. So I think that this is a decision which the UK will make on its own but I think that there are a lot of data out there about which groups are infected by these viruses and so I think that the UK authorities can look at those kinds of data and make their own decisions.

Question 2: Laura McGinnis, Reuters: I was wondering if you could tell us about the supplier vaccine worldwide and how you view that at the moment.

Dr Fukuda: Worldwide, that capacity to make influenza vaccines is about 350-400 million dozes. The capacity to make vaccines has been increasing in the past few years and it's expected to continue increasing. A lot of this is driven by the concerns about both the H5N1 virus and about the potential concerns about pandemic influenza virus. But interestingly enough, these concerns about avian and pandemic influenza have really helped push the technology about these influenza vaccines so for example there is work going on about a so called "adjuvant" vaccines and even though these vaccines are not commonly used for regular influenza right now, this kind of technology could greatly increase the vaccine supply in the world so, anyway, that's where we stand right now but in the not so distant future I expect the capacity of the world to increase to make these vaccines.

Question 3: Aves Deravano from Canadian TV Toronto: Yes good morning Doctors, I wonder if you could just go a little further into detail on the match this year. You have 3 new strains in the vaccine and how does it match what's being seen in the SH and how severe is the disease there and what might we expect here?

Dr Fukuda: OK. Last year, in the NH, the influenza seasons were as considered generally mild, and then this year, this past year in the SH, the influenza seasons were again considered generally pretty mild. The viruses contain in the vaccine for the NH match pretty well with the viruses which had been detected in the SH. We are simply not able to tell how the season is going to evolve in the NH. Again, as I mentioned earlier, we are at the very start of the season and without really seeing how the first outbreaks go, we really cannot predict what the season is going to be like.

Question 3 continued: Canadian TV, Toronto: And what are the 3 strains that you have in the vaccine this year?

Dr Fukuda: There is again usually… or I should say every year in the vaccine, there are 3 viruses which are covered. One is an influenza AH1N1 virus. One is an influenza AH3N2 virus and one is a B virus. And so that's what is contained in the vaccine for this coming season.

We have no further questions.

Thank you. You're free.

Dr Fukuda: Actually ...inaudible... could I just add one point to that last question.

Mr Hartl: Yes go ahead.


Dr Fukuda: OK, just a little bit more specific detail on the vaccine for this coming season. You'll have to get your pencils sharpened for this but for the H1N1 virus it's an A/Brisbane/59/2007(H1N1)-like virus. So this is a mouthful. The second virus is also called A/Brisbane/10/2007(H3N2)-like virus. The third virus is called B/Florida/4/2006- like virus. Anyway, it's a lot of detail and you can write to us and we can get you the viruses by name if that's helpful, in writing but the vaccines are the same for both the northern hemisphere and the southern hemisphere this year.

Thank you.

We have another question from Mrs L ...inaudible...

Hi, thanks for taking my question. I am wondering why there is the perception that the next season is going to be severe. I have heard some bits and pieces about the Brisbane strain and I was just wondering what the facts were on that. Thank you.

Dr Fukuda: Well, I'm not 100% positive why people are thinking that the upcoming season will be severe but I think that the most likely reason is that because the northern hemisphere vaccine contains 3 different strains from last year, that some people have interpretated that to mean that it will be an unusually severe season but so far this year we have had very few reports of influenza - just sporadic cases - and otherwise there is no real indication of how this season is going to evolve yet.

Thank you.

Next question comes from Lara MacGuinness from Reuters.

Lara MacGuinness: Hi, I just wanted to be sure that I understood exactly why the 3 strains have changed from last year to this year. What are the reasons that you ...inaudible... stipulated ...inaudible

Dr Fukuda: That's a good question Lara. The influenza viruses are well known for being able to change and so because of how they are put together, basically they mutate a lot and so their genes mutate and as they do so, and they do this on almost a continuous basis, they change over time and in the vaccine-strain collection process one of the things we do is try to assess how much they have changed, and then if we see that the viruses in the vaccine are no longer well-matched to the viruses that are circulating round the world, then that's a signal to the expert committee that we need to update the viruses in the vaccine. Now, the vaccine contains 3 different viruses and these viruses independently mutate and these lines of viruses change over time independently so this is a year in which all 3 of the viruses had changed sufficiently for the expert committee to recommend that these strains should be updated. Now that change in itself, this kind of change is a common occurrence and every year we usually have one or two viruses which change. So the changes themselves do not mean that this season is going to be severe it just means that the viruses are changing out there and that we need to keep the vaccine updated. So this is a pretty regular process.

Mr Hartl: Any further questions.

Arkadin: There are no further questions.

Mr Hartl: OK. We will give 2 minutes to people to think if there is something they wanted to ask and I might ask Dr Fukuda just to reiterate that before the season starts.

Dr Fukuda: Yes, I think again at the beginning of each year there are always a lot of concerns about what the season is going to look like and we know when we look backwards at seasons that they can be highly variable. There are some seasons which are pretty variable. There are some seasons in which the levels of hospitalizations and deaths can be quite high but at the beginning of each season we simply cannot predict what it's going to look like. And so, we are always very careful to let people know we don't know what's going to happen, however vaccination is by far the best means to protect yourself given that uncertainty so we are very, very proactive in trying to point people in the direction that there are things that they can to protect themselves and vaccination is the most important of these so.

Mr Hartl: Thank you. I believe that there is another question now. Is that from Rebecca? Is that correct?

Yes, we have a question from Rebecca.... from the Daily Telegraph.

Rebecca Smith: Hi, I just wanted you to clarify. I think that we are getting reports suggesting that Asia might be bad because there have been some experts in Australia saying that they have had a very severe year there and lots of deaths and the Brisbane strain is now heading into the northern hemisphere for our winter season. I think that's where the reports of a bad season are coming from. And also, I wanted to ask about the use of antivirals. In the UK we have quite strict criteria on the thresholds of 'flu that need to be circulating in the community before we use antivirals and they are quite heavily restricted. Do you think we should be using them more liberally to prevent wider spread of a disease?

Dr Fukuda: OK. Thank you for those questions. We are in close contact with the public health in Australia and one of the global reference centres is located in Australia so we, you know, we talk with them frequently and see them frequently and the influenza season in Australia was pretty mild so I think that, I'm no quite sure why there are rumours about a severe season in influenza, a severe influenza season in Australia but this is something that we can confirm directly, that the public health authorities in Australia considered this to be a mild season. Now in terms of antivirals, again the patterns in how often these drugs are used is pretty different from country to country. So, for example, in Japan these antivirals are used quite liberally and they are used quite often by the physicians but a lot of these differences in practice depend on the health care system so again, in the United Kingdom the health care system is somewhat different than it is in Japan and I think it's, you know, I really cannot direct or guide a country on how it should be using its antiviral drugs but it is important for people to know that these specific drugs are available which can be used against influenza. And then again, it is really up to the health authorities and the physicians in a country to decide how to use them.

Rebecca Smith: And are you worried about the potential for resistance against antivirals. I know that we are starting to see that and do you think that it is worth restricting the drugs in order to prevent widespread resistance in the event of a pandemic occurring?

Dr Fukuda: Well, resistance is always a concern with any kind of drug which is used against infectious diseases. So, for example, we are always concerned about resistance against bacteria or in the fight to tuberculosis and that equally is true for influenza viruses. Nonetheless these newer antiviral drugs in general have been pretty good in terms of low resistance levels but this past year we did see an unusual phenomenon where one type of influenza virus developed high levels of resistance and the unusual thing about this development is that this resistance pattern seemed to be independent of the use of the drug. So, for example, in the countries which had the highest use of Oseltamivir, which is one of the antiviral drugs, the resistance levels were quite low whereas in countries which used very little of this drug, the resistance levels were high. So, it's always something that we have to keep our eyes upon but it isn't I think a concern, or it isn't a reason for not using these drugs when they are indicated. I'm saying this for any other antiviral or antibiotic drug.

Rebecca Smith: Thank you.

Mr Hartl: OK. I think we're just about finished unless Dr Fukuda wants to add anything.

Dr Fukuda: No, I think Gregory that's about it. I do, let me just add one more point about the resistance. I think that in Europe it's been very interesting with the anti, with the resistance patterns to Osertamivir and I just want to point out that within the continent they have been pretty variable. They differed a lot from country to country so again it's one of those reminders that we really, are often taken by surprise by what these influenza viruses do. I think it is another reason to point out again that given all these sorts of patterns that vaccination is year-in and year-out probably the best bet for anyone who wants to be protected against this disease. Thank you.

Mr Hartl: Dr Fukuda. Thank you very much and thank you to all of you who joined us. A transcript of this virtual press conference will be posted in the next couple of hours as will an audio file on the WHO media centre site. Arcadia thank you very much and we are signing off. Thank you.