Millions of bird deaths as US hit by avian flu outbreak

US officials believe nearly 24m poultry birds, mostly chickens and turkeys, have died of flu since virus strain identified in February

Millions of birds have died in the US in recent weeks, because of a contagious strain of highly pathogenic avian influenza, popularly known as bird flu.

The bird flu has also led zoos across the US to temporarily close aviary exhibits and move birds away from the public. At zoos from Colorado to Maryland, species ranging from ostriches to penguins have been moved indoors.