No more turkey farms in a US county have tested positive for bird flu since an outbreak at 10 farms, where nearly 250,000 turkeys will be killed as a result.
That 100 farms tested over 24 hours in Dubois County came back negative was a sign control measures appeared to be working, said Denise Derrer, a spokeswoman for the Indiana State Board of Animal Health.
She called the outbreak one of the worst to strike Indiana, adding it could take several weeks before it is known for sure it has been contained.
The infections were reported on Friday and Saturday.
All 60,000 turkeys at the first farm where the bird flu was detected have been euthanised. Not all the 250,000 had yet been killed, Derrer said, though she did not have specific figures.
Most of the additional tests were done within about a 9km radius of the infected farms. But some producers tested farms outside that radius - a few even in Illinois near the Indiana border, Derrer said.
"They want to make sure it is not being spread," she said.
Confirmation of new bird flu cases alarmed industry officials after the spread of the H5N2 virus last year. That outbreak led to the deaths of about 48 million turkeys and chickens.
The H7N8 virus has not yet been found in wild birds, suggesting the virus could have developed in wild birds that spent the winter in southern Indiana, USDA spokeswoman Andrea McNally said on Friday.
