There are reports Tuesday of another person killed by that new strain of bird flu in China.
Monday, four new cases of the H7N9 avian influenza were reported there, bringing the total number of people infected to 24, with seven deaths.
Shanghai and the capital cities of neighboring provinces Zhejiang Jiangsu have all reported H7N9 cases and halted the sale of live poultry.
Shanghai also slaughtered all fowl at a market where the virus was detected in pigeons being sold for meat.
The big fear is whether there are far more cases than have been reported, and that the flu - which is now spreading from birds to humans - will at some point spread from humans to humans.
Chinese authorities have halted live poultry trade in cities where cases of this bird flu have been reported, and they have ordered the slaughter fowl in markets where the virus has been detected.
Meantime, Vietnam is confirming its first human death from bird flu in more than a year. A four-year-old boy died after contracting the H5N1 strain of bird flu. Health officials say it's not related to the new strain in China.
This segment aired on April 9, 2013.