According to The Lancet, researchers have now genetically-engineered strains of bird flu that can pass easily from ferret to ferret (the animal model often used in flu research) by means of aerosol, that is to say by air exhaled from the lungs. This demonstrates the possibility that a bird flu virus could emerge that would threaten the health of mankind.
The first justification for deliberately engineering a bird flu virus that is easily transmitted from ferret to ferret is that it alerts the world to the potential hazard to public health posed by the virus, thus countering a dangerous complacency about it; the second is that it might aid attempts to produce a vaccine against or a treatment of the illness. But critics argue that the research actually increases the risks of disaster rather than reduces them, either by inadvertence or (if the technique for engineering viruses fell into the wrong hands) by malice.
This is tantamount to going around setting forest fires to alert the public to the danger of fire.