H1N1 mutation found in some flu fatalities

updated 10:10 a.m. PT, Fri., Nov . 20, 2009

OSLO - Norwegian health authorities said Friday they have discovered a potentially significant mutation in the H1N1 influenza strain that could be responsible for causing the severest symptoms among those infected.

"The mutation could be affecting the virus' ability to go deeper into the respiratory system, thus causing more serious illness," the Norwegian Institute of Public Health said in a statement.

The concern over mutation of the H1N1 virus came as health officials said the H1N1 virus is moving eastwards across Europe and Asia after appearing to peak in parts of western Europe and the United States, the World Health Organization (WHO) said on Friday.