Echoing the encouraging results from Mexico, Dr. Palese, a flu expert at New York's Mount Sinai Medical School, said "he saw no reason to believe the virus was particularly lethal and said it was behaving more like a garden-variety flu that strikes every winter." CBC News update, May 2, 2009.

On the other hand, Dr. Fukuda of the WHO says it is too early to tell with certainty.

One of the problems with determining the seriousness of the cases in Mexico is that the normal flu season was late there, and separating normal flu cases from H1N1 means many tests must be carried out. Thankfully most are negative for H1N1.