Frequently Asked Questions About Bird Flu
What About the Lab-Created Bird Flu Mutant?
During the fall of 2011, researchers from Erasmus Medical Center in the Netherlands made a stunning announcement. They had taught H5N1 the nasty trick of going airborne and spreading among ferrets.
Why ferrets? Nearly all human flu bugs spread easily among ferrets. They are commonly used in studies of human flu viruses.
"The virus is transmitted as efficiently as seasonal flu," lead researcher Ron Fouchier, PhD, told New Scientist magazine.
At the University of Wisconsin, a team led by virologist Yoshihiro Kawaoka, PhD, DVM, also created an H5N1 mutant that spreads among mammals.
Both research teams were funded by the U.S. National Institute of Health. In a statement, the NIH says the research shows "that the H5N1 virus has greater potential than previously believed to gain a dangerous capacity to be transmitted among mammals, including perhaps humans."
The NIH funded the research because it felt there was a need for more information on how H5N1 might learn to spread among humans. The U.S. National Science Advisory Board for Biosecurity asked the study authors not to publish crucial information about the creation of the mutant viruses. The details will be made available only to qualified researchers.
But the studies remain extremely controversial. Some senior scientists have said the mutant viruses should never have been created. They note that while the mutant viruses are housed in state-of-the-art containment facilities, the risk of escape is not zero.
It's also not unprecedented. In 1977, an extinct H1N1 flu bug re-emerged along the Russia/China border. This so-called "Russian flu" led to widespread epidemics. Although officials denied it, many scientists believe the virus had escaped from a laboratory.
Has Bird Flu Been Seen in the U.S.?
H5N1 bird flu has never been detected in the U.S.
Various strains of bird flu pop up in U.S. poultry from time to time. When they do, all affected poultry flocks are culled.
For example, in 2004 a highly dangerous bird flu strain appeared in a Texas chicken flock. The outbreak involved an H5N2 virus (not the H5N1 bird flu). By April 2004, the outbreak had been eradicated. No human infections were detected.
What Are the Symptoms of Bird Flu in Humans?
Bird flu symptoms in people can vary. Symptoms may start out as normal flu-like symptoms. This can worsen to become a severe respiratory disease that can be fatal.
In February 2005, researchers in Vietnam reported human cases of bird flu in which the virus infected the brain and digestive tract of two children. Both died. These cases make it clear that bird flu in humans may not always look like typical cases of flu.
No human cases of bird flu have been seen in the U.S. or North America. But as a precaution, the CDC is asking people who have traveled to East Asia to see a doctor if they develop flu-like symptoms. If so, it's important to tell the doctor about having visited these areas so the proper tests can be done.