Bird flu that originated from the US poultry farms is now reaching alarming levels after Iowa, the biggest US egg producing state, said that flocks housing nearly 16% of the state's egg laying chickens might be infected.

As per the figures released by the state and federal agriculture departments, roughly 9.5 million chickens in Iowa that were confirmed to be infected for the virus are presumed to have infected flocks to more than 13 million nationwide.

It has been found that about 30 cases of the disease have been confirmed in the US over the past few weeks. Officials are worried that if the situation continues like this, it will be the worst domestic outbreak in three decades.

Bill Northey, Iowa Secretary of Agriculture, said, "Certainly, there is a lot of healthy, active birds out there still laying eggs, and we hope this doesn't move beyond this. We don't know what's going to happen next. There is a big economic impact".

US farm owners have stepped forward for clean-up efforts. On the other hand, Minnesota Governor Mark Dayton announced state emergency as poultry buyers from Europe to Asia would restrict shipments to America.

The worsening poultry condition can cause loss of roughly $44 billion, which is made from poultry and eggs produced in the US.

The flu has even started showing up in wild birds and waterfowl since December along the Pacific Coast.

Government figures showed that rate of reported cases vastly accelerated since March as commercial flocks in the Midwest began to report infections.

Center Fresh Group said on Monday that the samples tested positive at two Sioux County, Iowa facilities with about 5.5 million birds, which were also included in the total state count provided by the agriculture department.

The USDA on Tuesday confirmed that a Sioux county flock with 1.7 million birds was tested positive for the virus.