AP reports that the U.S. government expects to spend $191 million to pay chicken and turkey farmers for birds lost to avian flu, Agriculture Secretary Tom Vilsack said Tuesday as he called for Congress to consider a disaster program for poultry producers similar to that for other livestock farmers.

That's just a fraction of the federal government's $700 million price tag for what is considered by many to be the worst animal disease disaster to hit the nation, Vilsack said. The government has spent $400 million on cleaning up dead birds and disinfecting and is paying to research and stockpile a bird flu vaccine in case the virus returns.

The bird flu killed 48 million birds, mostly turkeys and egg-laying chickens in 15 states as it swept through the Midwest. Iowa, Minnesota and Missouri lost the most birds.

Vilsack spoke Tuesday at a bird flu conference in Des Moines, where the poultry industry and agriculture officials are talking about how to make farms more secure and how to better respond if the virus is again dropped on farms from waterfowl migrating south this fall. The conference was closed to the public and the media except for opening speeches by Vilsack and Iowa Gov. Terry Branstad. Organizers said they wanted to ensure an open discussion of what went wrong and how to improve responses.

"I do think we'd be better off as a nation if we had for poultry producers a disaster program similar to what we have for livestock producers," Vilsack said. It would be less costly to the government than dealing with outbreaks as individual disasters, he said.

A proposed insurance program was cut from the 2014 farm bill as Congress sought to reduce spending, Vilsack said.

Of the 211 U.S. commercial poultry barns affected by the bird flu, 90 have been cleaned and disinfected and nearly 70 are ready to bring in new birds, Vilsack said. By the end of September, infected farms should be ready to restock, he said.

Branstad worries about a return of bird flu. The state's egg production fell 44 percent last month from a year ago after losing nearly 32 million birds, mostly egg-laying hens, to flu.

"We want to be as prepared as we can and do what we can from a biosecurity perspective to avoid it recurring or having it spread like it did this spring," he said.