What does a bird flu pandemic mean and will it happen?
Pandemic means epidemics or cases in more than one continent. Pandemic flu will happen sooner or later. They happen from time to time as new strains of flu virus emerge and because humans have little or no immunity to these viruses. Three examples of these occurring are in 1918, 1957 and 1968. The 1918 pandemic killed around 50 million people worldwide, and pandemics in 1957 and 1968 were milder.