At least two people have died of bird flu in Turkey since an outbreak was announced last week. More than a dozen people, mostly children, have come down with the H5N1 avian flu strain after handling infected birds. Alarmed that the virus was spreading rapidly among birds, Turkish authorities began a massive slaughter of poultry. But new research indicates the disease may not be so deadly after all. Swedish and Vietnamese scientists found that many people in Asia who handled infected birds may have contracted a mild case of the flu and recovered within a few days. That would indicate that the mortality rate from the flu is far less than the 50 percent that has been feared.