If left unchecked, a pandemic flu today could kill a total of 150 million people in 20 months.<br />Every pandemic flu, from that Spanish flu in 1918 to the 2009 H1N1 outbreak, has originated in birds.<br />So every year, flu researchers flock to Reed's Beach, in Delaware Bay in New Jersey.<br />There, a seasonal frenzy of migrating birds creates a unique breeding ground for the flu virus.<br />Taking samples from the birds' rear ends, and their feces, is critical ritual meant to help prevent the next pandemic flu.<br />About 20% of them are pooping out influenza. Where do so many infected birds come from? We don't really know. Robert Webster, Flu Expert St Jude Children's Research Hospital <br />
