Based on the assessment of all available information and following several expert consultations, Dr Margaret Chan, WHO's Director-General last night raised the current level of influenza pandemic alert from phase 4 to 5. She stated

that all countries should immediately activate their pandemic preparedness plans, including heightened surveillance, early detection and treatment of cases, and infection control in all health facilities. But she stopped short of any restrictions or recommendations on regular travel or closure of borders.

In a full statement which appears below, Director-General Dr Margaret Chan calmly outlined the WHO's assessment of the situation, based on all of the available information and several expert consultations: ‘On the positive side, the world is better prepared for an influenza pandemic than at any time in history. Preparedness measures undertaken because of the threat from H5N1 avian influenza were an investment, and we are now benefiting from this investment. For the first time in history, we can track the evolution of a pandemic in real-time.

‘I thank countries who are making the results of their investigations publicly available. This helps us understand the disease. I am impressed by the work being done by affected countries as they deal with the current outbreaks. I also want to thank the governments of the USA and Canada for their support to WHO, and to Mexico. Let me remind you. New diseases are, by definition, poorly understood. Influenza viruses are notorious for their rapid mutation and unpredictable behaviour.

‘WHO and health authorities in affected countries will not have all the answers immediately, but we will get them. WHO will be tracking the pandemic at the epidemiological, clinical, and virological levels. The results of these ongoing assessments will be issued as public health advice, and made publicly available. All countries should immediately activate their pandemic preparedness plans. Countries should remain on high alert for unusual outbreaks of influenza-like illness and severe pneumonia.

‘At this stage, effective and essential measures include heightened surveillance, early detection and treatment of cases, and infection control in all health facilities. This change to a higher phase of alert is a signal to governments, to ministries of health and other ministries, to the pharmaceutical industry and the business community that certain actions should now be undertaken with increased urgency, and at an accelerated pace. I have reached out to donor countries, to UNITAID, to the GAVI Alliance, the World Bank and others to mobilize resources.

‘I have reached out to companies manufacturing antiviral drugs to assess capacity and all options for ramping up production. I have also reached out to influenza vaccine manufacturers that can contribute to the production of a pandemic vaccine.

‘The biggest question, right now, is this: how severe will the pandemic be, especially now at the start? It is possible that the full clinical spectrum of this disease goes from mild illness to severe disease. We need to continue to monitor the evolution of the situation to get the specific information and data we need to answer this question. From past experience, we also know that influenza may cause mild disease in affluent countries, but more severe disease, with higher mortality, in developing countries.

‘No matter what the situation is, the international community should treat this as a window of opportunity to ramp up preparedness and response. Above all, this is an opportunity for global solidarity as we look for responses and solutions that benefit all countries, all of humanity. After all, it really is all of humanity that is under threat during a pandemic. As I have said, we do not have all the answers right now, but we will get them. Thank you.

Dr Margaret Chan,
Director-General,
World Health Organization.