(MELBOURNE, Australia) — Three patients remained critically ill on Thursday, three days after a rare condition known as thunderstorm asthma killed four people and sent hundreds to hospitals in Australia’s second-largest city, an official said. Doctors were amazed there were not more fatalities given the numbers of people who suffered cardiac arrests and struggled to breathe when a wild thunderstorm struck Melbourne on Monday night, Victoria state Health Minister Jill Hennessy said. The storm caused rain-sodden ryegrass pollen to explode and disperse over the city, with ruptured particles penetrating deep into lungs.