I understand the concern that all are showing with respect to the N294S mutation that has shown up recently in the NA segment of Egyptian patients. However, testing to date indicates that such mutations in the H5N1 virus show only moderate resistance to oseltamivir. Nonetheless, we should continue to look for the source of such viral changes. To date they only been found in early 2000 isolates outside this Egyptian instance.
On the other hand, the H274Y mutation in the NA segment has shown to be substantially resistant to this antiviral drug. It has cropped up in various places and should be a serious cause of concern, especially in Russia, where we apparently have new outbreaks of H5N1 in foul.
This nasty H274Y mutation has already surfaced in Russia (A/swan/Astrakhan/1/2005 and again in A/swan/Astrakhan/Russia/Nov-2/2005). Astrakhan is a city of a half a million people, and with new outbreaks of H5N1 in the area, perhaps some attention should be directed their way as well. If human infections surface, throwing a Tamiflu blanket over the patients may have little, if any affect.
On the other hand, the H274Y mutation in the NA segment has shown to be substantially resistant to this antiviral drug. It has cropped up in various places and should be a serious cause of concern, especially in Russia, where we apparently have new outbreaks of H5N1 in foul.
This nasty H274Y mutation has already surfaced in Russia (A/swan/Astrakhan/1/2005 and again in A/swan/Astrakhan/Russia/Nov-2/2005). Astrakhan is a city of a half a million people, and with new outbreaks of H5N1 in the area, perhaps some attention should be directed their way as well. If human infections surface, throwing a Tamiflu blanket over the patients may have little, if any affect.
