Health officials are not sure how the boy from Ha Nam province became infected with the H5N1 virus.

The boy was the 52nd person to die of bird flu in Vietnam.

Provincial Health Department director Nguyen Lap Quyet says the boy's family raises chickens at their home, and some of them became sick in late February.

After several of those birds died, the family slaughtered and cooked one of the remaining birds. -- AP