The World Health Organization (WHO) said there was no new evidence that the H5N1 virus has become more easily transmittable from poultry to humans, local newspaper Vietnam News reported Friday.
The comments by WHO's communications officer in Vietnam Dida Connor follow fears of a potential new outbreak of bird flu among humans.
Two local people have recently been confirmed to have contracted bird flu in the two northern provinces of Vinh Phuc and Thai Nguyen.
However, the virus was very adaptable and became more easily transmittable among poultry, according to chief technical advisor on avian influenza of the UN's Food and Agriculture Organization in Vietnam, Jeffrey Gilbert.
Since early May, bird flu has hit a total of 16 cities and provinces across Vietnam.
The Ministry of Agriculture and Rural Development has asked local authorities nationwide to take specific anti-bird flu measures, including disinfecting poultry farms two or three times a week, sterilizing hatching machines after hatching fowl eggs, and disinfecting slaughter houses, markets and vehicles used for transporting fowls.