A rare condition known as thunderstorm asthma sent hundreds of people to hospitals in Australia's second-largest city, and four deaths had been confirmed by Wednesday. The pollen caused asthma attacks in some patients who had never suffered from asthma before. Professor George Braitberg, head of the Royal Melbourne Hospital's emergency department, likened the scene in the hospital on Monday night to a war zone. Seven asthma patients had been transferred to the hospital's intensive care unit, he said. Some patients had never before had asthma attacks, he said.

Source: CBC News November 23, 2016 11:14 UTC