Royal Adelaide Show organisers confirmed the decision was made out of an "abundance of caution", with the event due to be held from September 5 and 13. Bird flu cases in the state make up more than three quarters of the national total of 155, the South Australian government confirmed on Friday. The Royal Adelaide Show decision will impact about 150 exhibitors, volunteers and stewards in the poultry and bird section. Questions have been raised over whether a similar approach would be viable with Australian birds and other animals as the deadly strain's national toll soars past 100. "If we're talking about vaccinating wild birds, I think that's a big task," he said.