"Influenza pandemics must be taken seriously precisely because of their capacity to spread rapidly to every country in the world," said Chan, remarking on the nine countries that officially have reported a total of 148 cases of swine influenza A/H1N1 infection. The United States has reported 91 laboratory confirmed human cases, with one death. Mexico has reported 26 confirmed human cases of infection including seven deaths. Other countries reporting laboratory confirmed cases with no deaths include Austria (1), Canada (13), Germany (3), Israel (2), New Zealand (3), Spain (4) and the United Kingdom (5).
"On the positive side," Chan noted, "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 benefitting from this investment."
According to Chan, for the first time in history, we can track the evolution of a pandemic in real-time. She thanked the countries that are making the results of their investigations publicly available. "This helps us understand the disease," she said.
"Let me remind you. New diseases are, by definition, poorly understood. Influenza viruses are notorious for their rapid mutation and unpredictable behavior," said Chan. "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 will be made publicly available.
She suggested that all countries 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," said Chan.
She acknowledged that the biggest question, right now is how severe will the pandemic be? Chan noted that it is possible that the full clinical spectrum of this disease goes from mild illness to severe disease.
"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," Chan said. "No matter what the situation is, the international community should treat this as a window of opportunity to ramp up preparedness and response."
She called for global solidarity as health organizations and governments look for responses and solutions that benefit all countries. "After all," she said, "it really is all of humanity that is under threat during a pandemic."