The H5N1 virus is becoming a truly global problem at an amazing speed, and this raises many urgent issues about human and animal health.
Will H5N1 come to the U.S.?
Scientists say almost certainly it will. Spring is approaching and wild birds throughout the world are beginning major migrations. The virus has now appeared in at least 40 countries. Migrating birds spread it to other wild birds and domestic poultry. Bird migration patterns cover the entire globe. The best bet is that birds will carry the virus across from Siberia to Alaska over the summer and then move down to the lower 48 states during the fall. But that is only a guess.
What are the dangers on arrival?
There is a huge economic threat to the poultry industry. Already farms are taking precautions to try to keep poultry sealed up indoors to prevent infections. Scientists say there is no danger from eating cooked poultry. But in other countries poultry consumption has dropped as much as 70 percent when the virus appeared in wild birds.
As for the dangers to human health from wild birds, there are serious, so far unanswered questions.
Do we need to worry about things like pigeons or bird droppings on windshields or picnic tables?
It is important to remember that so far there have been fewer than 180 human cases worldwide and almost all of them came from contact with infected poultry. No cases are known to have come to humans from wild birds.
In Asia and Europe birds transmitted the virus to cats, do we need to keep our pet cats indoors?
There are no known cases of the virus spreading from cats to humans. But according to Dr. Walter Boyce, director of the Wildlife Health Center at the University of California, Davis, bird flu can best be explained as a huge experiment going on in nature. We simply don't know many of the outcomes.
Will the virus mutate so that it can spread it easily from person to person?
No one knows whether this new movement in birds makes that more likely.