The Rise of H5N1 in the United States

H5N1 has been something that some of us have been dealing with extensively since 1997, when it first emerged in the poultry markets of Hong Kong. We also continue to receive reports about H5N1 avian flu being detected in mammals in several countries. What we haven't seen is evidence of ongoing sustained transmission in humans, which is the key to a flu virus causing the next pandemic or becoming a problem in general in humans. Where I think the human risk is today and I hope this never materializes is H2N2.