However, the head of the Department for Preventive Medicine and Environment, Nguyen Huy Nga, warned that bird flu remains  a threat to poultry despite relief from being transmitted to human beings to become a pandemic.

In May, bird flu outbreaks were discovered in five provinces, namely Tra Vinh, Can Tho and Kien Giang in the Mekong Delta and Nghe An and Ha Tinh in the central region.

The situation could still become worse in coming months during the harvest season when poultry flocks are released into crop fields for food, said Mr Nga.

He warned that such actions pose a high risk of transmitting the deadly virus from poultry to human beings.

To cope with the threat, the Ministry of Health has held training courses for rapid-response teams in Hanoi, Thai Binh and Quang Ninh provinces in the north, and in Nha Trang city of central Khanh Hoa province.

The ministry has also been given H5N1 virus-proof masks and protective suits from Japan’s Mochigase company and the World Health Organisation.

The Department for Preventive Medicine and Environment has also called for all border quarantine agencies to tighten security.