Informal dinner with Ministers of Health of the European Union to discuss avian influenza
Thank you for this opportunity to discuss the avian influenza situation with you. I will tell you briefly what we, at WHO, see as the most important points to be aware of at present. Then Dr Klaus Stohr, our scientist in charge of influenza control, can provide more detailed technical information, as needed.
The outbreaks of H5N1 avian influenza in poultry have been occurring in eight Asian countries. They are unprecedented in scale, geographical spread and economic impact on the agricultural sector.
Human cases have occurred - six in Thailand and nineteen in Viet Nam - with high fatality. The small number of human cases compared to the large number of birds infected over a wide geographical area suggests that this virus may not easily infect humans.
No case of human-to-human transmission is known to have occurred to date. However, the continuing presence of infection in poultry may favour the emergence of a new influenza subtype that can spread easily among humans. This rare event would mark the start of an influenza pandemic, with serious consequences for human health worldwide.
Public health has to be given the highest priority in weighing up the options for preventing and containing these outbreaks. Where human life is put at risk the costs - both human and economic - are incalculable.
Rapid and complete sharing of information is one of the most important means we have of preventing and controlling these epidemics.
Measures aimed at eliminating the disease in poultry will reduce the presence of the virus in the environment, and thus reduce opportunities for human infection. Previous outbreaks, in Hong Kong and the Netherlands, were controlled by immediate culling of infected flocks, quarantine and disinfection of farms, strict bio-security, restrictions on the movement of animals and compensation of farmers.
Both of those outbreaks were in industrialized areas, however, with concentrated large-scale poultry production and well-developed infrastructure for agriculture and health. The present situation in Asia is different, with 80% of the poultry being raised by families in small free-range flocks on backyard farms. The same measures are needed but applying them can require more complex procedures that are more difficult to carry out.
One danger, therefore, is that the H5N1 virus could become established in bird populations in this region of Asia. From there it could spread to other parts of the world.
We have no single blueprint for the control of this virus in animals. In the last forty years there have been only eighteen outbreaks of highly pathogenic avian influenza worldwide. The evidence and experience drawn from these are not sufficient to provide universally applicable recommendations for a rapid response in affected countries.
Control measures must be tailored to each country's unique situation, epidemiology and capacity. The health and agricultural sectors must work hand in hand to design and implement these measures.
Despite uncertainties, experts fully agree that immediate culling of infected and exposed birds is the first line of defence both for human health and for agriculture. Culling has to be carried out in a way that does not fuel more human cases.
Measures such as vaccination of healthy flocks may be useful, if combined with measures that prevent further spread of infection. However, vaccination must not be seen as a reason for relaxing vigilance or compromising the other control measures needed.
WHO emphasizes three goals: first, to avert an influenza pandemic; second, to control the present human outbreaks and prevent further spread; and third, to conduct the research needed for better preparedness and response. This includes the immediate development of a new vaccine for humans against H5N1.
WHO has teams in the field in several countries. In Thailand and Viet Nam, these teams are supporting local staff in the clinical management of cases, in strengthening of surveillance to improve case detection and in confirmation of diagnosis. Laboratories in the WHO influenza network are providing further diagnostic support and conducting the essential “detective work”, at the molecular level, needed to understand this outbreak better. Work on the development of a vaccine is moving forward but it will still take four to six months before a significant amount of vaccine will be available.
Several other research projects have also been initiated. Results from these studies should further deepen our knowledge, particularly when it comes to recommending the best tools for control.
Preparedness for a potential influenza pandemic is an overriding concern. Here, WHO and countries have been guided by a World Health Assembly Resolution on prevention and control of influenza pandemics and annual epidemics, adopted last year. That resolution sets out responsibilities for countries. It asks WHO to search, with its partners, for solutions to the present global shortage of vaccines and antiviral drugs, also for pandemic situations. Inequitable access to vaccines and antivirals was another problem identified for attention.
We are working on all these fronts right now, with great urgency, as a precautionary measure. We are also investigating measures that could slow international spread should we find we face a pandemic situation.
I am pleased to inform you that we will be holding a meeting from 16 to 18 March to move the international community forward on these urgent issues.
I want to express my thanks for the strong support that the EC has been giving to our work, for example, in capacity building and other activities in Viet Nam, following Commissioner Byrne's visit. We fully support the development of your new Centre for Disease Prevention and Control and we are ready to provide advice on this as you require. Our strong working relationship is of great value across the whole health agenda.
Those are the most important points I wanted to cover. There are many others that may be of direct relevance to your situations, and of course we will be very happy to try and answer your questions.