Gallaya Riga, Niger – "Eggs and chickens are to sell, not to eat, and we buy grain with the money."

Nana Aicha, a village homemaker, is explaining the facts of life. Even though the puny village children could obviously use some protein, eggs and poultry are too precious to eat. They are transported in cages across the border by ox cart to sell to waiting Nigerian traders.

One day in February 2006, villagers brought back something besides cash – the bird flu virus.

Authorities think that the traders had the virus on their clothes or vehicles – the disease had already broken out in Nigeria – and passed it to the poultry. Villagers returned across the arid landscape to Niger in the evening with some unsold and now infected birds, spreading the virus to border villages and towns.

The effect was devastating and illustrates what would happen to poorer parts of Africa if the deadly disease spreads across the continent.

"We lost everything, because our chickens and ducks died overnight or because the government came and killed them," says Ms Aicha. "We have a few goats and cattle we can sell in an emergency, but mostly we grow millet and sorghum, and depend on poultry for cash. With the cash we buy grain for our daily diet."

"Today I'll feed my five children and myself on millet, rice and some milk, salt and chillies," she says.

Ali Abdu, the village chief, seems surprised when asked if the villagers eat fruit and vegetables. "We can go six months without even eating meat," he says.