He fed them all the same amount of food, but only the infected chickens became obese.

And it seems unlikely that infected chicken will find its way to supermarkets.

In the second experiment, three cats were fed infected chicken.

That makes it extremely difficult to keep live, infected chickens from being sold in markets.

All of the human cases so far are from contact with infected chickens, but not from eating them or eggs.

The human cases were believed to have resulted from direct contact with infected chickens, except for possibly two cases in Vietnam.

When infected transgenic chickens were present, however, the majority of the other birds in the cage survived, even if they didn't carry the transgene.

Dr. Sims said the influenza was very aggressive, killing virtually all the infected chickens within days.

Atherosclerosis is induced in experimentally infected chickens.

"At this point, we have seen no rationale to have a ban," he said, adding that proper cooking kills the virus even in infected chickens.