Pandemic influenza and other emerging epidemic diseases present a major threat to life, economies and security in an increasingly globalized world.
The impact of disease epidemics has increased dramatically as the world becomes ever more interconnected. For example, airlines now carry an estimated 1.6 billion passengers every year - a number equivalent to more than 20 percent of the world population.
Human pandemic virus
The current avian influenza outbreaks are primarily confined to animals. But if the avian influenza virus changes into a human pandemic virus that can be transmitted in a sustained manner, it will most likely spread worldwide, affecting all populations, regardless of national boundaries or socio-economic status.
Once a fully transmissible human pandemic virus emerges, it is expected to encircle the globe within three months. Because a pandemic strain would be of a new subtype that had not previously circulated in humans, it is thought that it would be dangerous since the vast majority of the population would have no immunity to it.
If an influenza pandemic appears, we could expect the following:
- Given the high level of global traffic, the pandemic virus may spread rapidly, leaving little or no time to prepare.
- Vaccines, antiviral agents and antibiotics to treat secondary infections will be in short supply and will be unequally distributed. It will take several months before any vaccine becomes available.
- Medical facilities will be overwhelmed.
- Widespread illness may result in sudden and potentially significant shortages of personnel to provide essential community services.
- The effect of influenza on individual communities will be relatively prolonged when compared to other natural disasters, as it is expected that outbreaks will reoccur.
Detecting a new pandemic virus
Continuous global surveillance of influenza is key.
WHO has a network of 112 National Influenza Centres that monitors influenza activity and isolates influenza viruses in all continents.
National Influenza Centres will report the emergence of an “unusual” influenza virus immediately to the WHO Global Influenza Programme or to one of the four WHO Collaborating Centres.
Rapid detection of unusual influenza outbreaks, isolation of possible pandemic viruses and immediate alert to the WHO system by national authorities is decisive for mounting a timely and efficient response to pandemics.