The current H5N1 virus is apparently not well “fitted” to replication in humans, although the genetic makeup of a small proportion of humans supports attachment and replication of the virus, if not its transmission. The specific receptor for the current avian influenza virus ({alpha}2-3 sialic acid) is found deep in the respiratory tract of humans
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Clearly, we must prepare for the possibility of an influenza pandemic. If H5N1 influenza achieves pandemic status in humans - and we have no way to know whether it will - the results could be catastrophic.