Bird flu has recently reappeared in Vietnam's seven southern cities and provinces, affecting over 35,600 fowls, according to a local newspaper Tuesday.

As of July 11, the disease had hit the localities' 18 communes and wards, either killing or leading to the forced killing of 22,470 chickens, 169 ducks and 13,000 quails, Liberation Saigon quoted sources from the Ministry of Agriculture and Rural Development as saying.

To curb the potential spread, Vietnam's Animal Department has asked cities and provinces nationwide to strengthen surveillance on transport and trade of poultry and their eggs. Fowls and eggs in provinces stricken by bird flu for 21 days at most are not allowed to be transported out of the localities.

In late March 2004, Vietnam declared an end to bird flu that killed 17 percent of its poultry population, and claimed 16 human lives since its outbreak in last December. A total of 43.2 million fowls nationwide either died or were culled, causing the local poultry industry to suffer direct losses of 1.3 trillion Vietnamese dong (82.8 million dollars).