Thousands of police officers patrolling Brisbane for the G20 Summit have been put on alert…. for a gastro bug.

According to a report by The Australian, police received a formal text message from the Queensland Police Service warning them gastro was making its way around the force.

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Queensland Police Service Assistant Commissioner Katarina Carroll said it was normal procedure.

“We text all 6000 police officers just to take the usual precautions because we don’t want to bring down many officers while they are on patrol,” she said.

“There was a gastro bug over the last couple of days… But it has subsided.”

World leaders have begun to arrive in Brisbane ahead of the summit, including Brazilian President Dilma Rousseff and Turkish Prime Minister Ahmet Davutoglu.