there have been a few suspected, isolated cases of it spreading human-to-human. I remember reading about it in the
National Geographic Magazine from last October. Clearly this is no reason to panic as it has not become fully transmissable, but even the WHO admits there have been suspected cases. Below mentions family members, but I remember reading somewhere about at least one health care worker - a male nurse in Thailand or Indonesia possibly. Also, a possible case of 2 or 3 health care workers in Vietnam. The other key thing is that these have occurred over the last couple years, and yet it still has not mutated to easy or efficiant transmission. The thing is you can't say there are no cases - but even given that, it is not yet significant.
This is from the WHO site - the link was given above earlier today:
What is the significance of limited human-to-human transmission?
Though rare, instances of limited human-to-human transmission of H5N1 and other avian influenza viruses have occurred in association with outbreaks in poultry and should not be a cause for alarm. In no instance has the virus spread beyond a first generation of close contacts or caused illness in the general community. Data from these incidents suggest that transmission requires very close contact with an ill person. Such incidents must be thoroughly investigated but provided the investigation indicates that transmission from person to person is very limited such incidents will not change the WHO overall assessment of the pandemic risk. There have been a number of instances of avian influenza infection occurring among close family members. It is often impossible to determine if human-to-human transmission has occurred since the family members are exposed to the same animal and environmental sources as well as to one another.
This one is from an article at Mayo Clinic site:
Bird flu fears: How dire the threat?
A Mayo Clinic specialist discusses timely questions about bird flu and its potential to cause a human pandemic.
James Steckelberg, M.D.
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Since 1997, bird flu has killed tens of millions of birds in several countries, and claimed the lives of dozens of people. Most people became sick through close contact with infected birds. But in a few instances, the H5N1 strain of the virus, which is uncommonly lethal, appears to have spread from person to person.
So far, the cases of human-to-human transmission have been rare and self-contained. But some experts fear that as the virus continues to mutate, it may produce a new, equally deadly strain that spreads easily among people, leading to a worldwide pandemic.
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