A Vietnamese healthcare official reported a total of four cases of bird flu infection in Vietnam in which the bird flu virus strain developed resistance to the antiviral drug branded Tamiflu.

The four local patients died after their illness progressed quickly, local newspaper Youth on Thursday quoted Nguyen Tran Hien, director of Vietnam's National Institute for Clinical Research in Tropical Medicine in Hanoi capital, as saying.

The resistance is not an abnormal phenomenon, he said, explaining that the world has reported cases of H5N1 resistance to two other bird flu medicines, which have not been used in Vietnam yet.

Most of bird flu fatalities in Vietnam are due to late diagnosis and treatment, local healthcare experts said, noting that Tamiflu is effective only for patients in the early stage of infection.

The newspaper, on Dec. 23, quoted Peter Hobby, an expert of the World Health Organization, as saying that Vietnam should research and then apply on a pilot basis a new bird flu treatment procedure: let patients take Tamiflu at a higher dose and in a longer time.

The organization and Vietnam would conduct the trial early next year, he said.

Vietnam's Health Ministry on Wednesday confirmed 66 human cases of H5N1 infections, including 22 fatalities, in 25 cities and provinces since December 2004, bringing the total respective numbers in the country since December 2003 to 93 and 42.

Source: Xinhua