The latest outbreaks to be confirmed by the US Department of Agriculture's Animal and Plant Health Inspection Service are:

• Minnesota, Brown county - 18,300 commercial turkeys;
• South Dakota, Moody county - 52,000 commercial turkeys;
• Minnesota, Renville county - 47,800 commercial turkeys;
• Iowa, Sac county - commercial turkeys, number pending;
• Iowa, Wright county - 434,800 commercial chickens.

The total number of outbreaks now reported is 205, with 44,994,993 birds now affected.

The outbreak in South Dakota is the first to be confirmed there since 18 May. The state now has 10 detections, with 1,168,200 birds affected.

Minnesota has been worse affected, with 96 detections and 8,375,050 birds either dead, or destroyed to prevent the disease.

Iowa now has 67 detections and 29,248,000 affected birds.

Meanwhile, Ohio and Michigan states have followed other states in banning shows of poultry this summer, despite the fact that neither have reported any cases of avian flu.

Ohio's Department of Agriculture described the move as an 'aggressive' precaution to protect Ohio's $2.3 billion poultry industry. The ban includes county and independent fairs, the Ohio State Fair, and all other gatherings of birds for show or for sale, including auctions and swap meets.

“This was a difficult decision because it means young people can’t show their birds at fairs, but it’s in the best interest of an industry that literally thousands of Ohio families and businesses depend on and which provides billions of dollars to our state’s economy.

"The right move isn’t always the easy move, but this is the right move, especially when you see just how devastating the virus has been to other big poultry states like Iowa and Minnesota.

"Ohioans need to do all we can to ensure that we protect our industry and that we help avoid a costly spike in the price of important foods like chicken, turkey and eggs,” said Ohio Department of Agriculture Director David Daniels.

Ohio is the second largest egg producer in the US and home to 28 million laying chickens, 12 million broilers, 8.5 million pullets and 2 million turkeys.

“One of the ways avian influenza spreads is by direct contact with contaminated materials coming from other infected birds.

"This means that exhibitions, auctions and swap meets where birds are co-mingling pose a high risk of unintentionally spreading this disease.

"Until we can be sure that there has been no transference from the wild bird population migrating through the state, we need to do all we can to minimize the exposure for our domestic birds,” said State Veterinarian Dr Tony Forshey.

Michigan's state Department of Agriculture and Rural Development said that the decision had been 'difficult' and that they understood how much time and effprt exhibitors put into preparing the birds.

Their state veterinarian Dr James Averill said: “The rapid spread of these avian flu viruses is historic and has impacted more than a dozen states across the US.

"While there are currently no known cases of HPAI in Michigan, commitment to protecting the health of all of the state’s poultry flocks - backyard and commercial farmers – led us to making this difficult decision.”