November 20, 2009

expert reaction to the news of a possible swine flu mutation in Norway

Scientists in Norway discovered a possible mutation to the H1N1 virus which could affect properties such as ease of transmission and virulence.

Dr John McCauley, MRC National Institute for Medical Research, said:

“It is recognised that the effects of many amino acid substitutions are highly dependent on the context of the protein in which they occur. This highlights the urgent need to carry out biochemical experiments to investigate any changes in the behaviour of viruses from fatal cases.

“It is notable that other changes at position 222 have occurred in the H1N1pdm viruses, notably the change from Aspartic acid to Glutamic acid in this position. In none of these viruses – whether they have aspartic acid at position 222, glutamic acid at 222 or glycine at position 222 – does the virus show marked differences in antigenicity in reaction with antiserum raised against the vaccine strain A/California/7/2009. It is anticipated therefore that vaccinated individuals should be as well protected from the variant virus as they are from the widely circulating H1N1pdm viruses.

“The number of fatal cases with the H1N1pdm is low and overall the death rate for this pandemic is low. But that should not lead to complacency.

“The form of the virus shows no evidence on a genetic basis for resistance to either of the antiviral drugs tamiflu or relenza.”