By AFPMore by this AuthorSYDNEYAn unprecedented "thunderstorm asthma" event has left four people dead and three fighting for their lives in Australia, with authorities Thursday scrambling to review their procedures after emergency services were overwhelmed. "This was a health emergency of an unprecedented scale," Hennessy said, adding that those affected appeared to have suffered respiratory problems and cardiac conditions. HAY FEVERThe unusual phenomenon is only known to have occurred in Australia several times, Asthma Foundation of Victoria chief Robin Ould said. Ould said those affected had asthma that is triggered by rye grass, or suffered from hay fever. Melbourne was particularly susceptible to "thunderstorm asthma" events as rye grass was found predominantly in the parks and farmlands around the city, the capital of Victoria, he added.

Source: Daily Nation November 24, 2016 08:59 UTC