THUNDERSTORM ASTHMA
* an epidemic of asthma symptoms during or immediately following a thunderstorm
WHAT CAUSED MONDAY'S EVENT?
* pollen blew into the city during the blustery day from the state's northern pastures
* pollen grains absorbed moisture during the evening thunderstorms and then burst into hundreds of tiny allergenic fragments
* those tiny fragments are small enough to penetrate deep into the airways, thus causing asthma
HOW MANY CALLS TO EMERGENCY SERVICES?
* 1900 triple-zero calls for ambulance from 6pm to 11pm - normally there'd be about 345 calls in that time
* most nights Ambulance Victoria has 10 to 20 cases on hold but at one point on Monday some 190 cases were waiting
* last similar event in Melbourne was November 2010
* most calls were for patients in Melbourne's west
* people had asthma who'd never previously experienced breathing issues
* paramedics called in help from the MFB, police and doctors to deal with the spike in demand
* "We essentially had a day's workload within five hours," Ambulance Victoria's executive director emergency operations Mick Stephenson said on Tuesday
MONDAY'S POLLEN COUNTS
* Melbourne - extreme with 102 grass grains per m3 of air recorded
THE MISCONCEPTIONS
* "my hayfever turned into asthma" - one in four people with hay fever also have asthma and pollen can trigger both conditions
* "rain washes the pollen away" - the rain causes pollen to burst so rain can exacerbate discomfort for some
Sources: Ambulance Victoria, Australasian Society of Clinical Immunology and Allergy, Melbourne Pollen and Deakin University.
