(Bloomberg) -- Australia’s global image is taking another hit, as smoke from wildfires sweeping the nation disrupts the Australian Open tennis tournament.

Practice for the first Grand Slam of 2020 was suspended Wednesday and qualification for the tournament was delayed over air quality concerns. Further decisions on play will be made using on-site data, in collaboration with the tournament’s medical team, the Bureau of Meteorology and Victoria state’s environmental protection agency.

Air quality in pockets of host-city Melbourne ranked worse than New Delhi and Shanghai on Wednesday, according to the World Air Quality Index. In similar conditions Tuesday, Slovenia’s Dalila Jakupović retired from her match after collapsing to her knees in a coughing fit and Australia’s Bernard Tomic sought medical treatment when he struggled to breath.

The Australian Open “should be postponed until the air quality is good,” Yuming Gu​o, head of the Monash Climate, Air Quality Research (CARE) Unit at Monash University said by phone. Playing in such conditions increases blood pressure, reduces lung function and can sometimes lead to death, he said.

Tennis Australia, the organizers of the event, didn’t immediately respond to a request for comment.

The fires have burned across an area twice the size of Switzerland while claiming at least 28 lives and destroying thousands of homes, bellowing choking smoke that’s reached as far away as South America. They’ve also pumped out more than half the country’s annual carbon-dioxide emissions, another setback for the fight against climate change.

The costs are mounting. Economists estimate the wildfires and associated drought could cut up to half a percentage point off GDP growth as agriculture, tourism and sentiment take a hit. The drag on the economy comes at a time when Australia can ill afford it, with households already reining in spending in response to record-high debt and stagnant real wages.

The tournament, one of Australia’s key overseas tourism draw cards, brought in an estimated A$290 million ($200 million) last year with a record 780,000 people through the turnstiles, according to the Victoria state government. And as the tennis wraps up, the Formula 1 Australian Grand Prix is scheduled to begin in the same city, an event that drew in more than 320,000 attendees in 2019.

To contact the reporter on this story: Matthew Burgess in Melbourne at mburgess46@bloomberg.net

To contact the editors responsible for this story: Edward Johnson at ejohnson28@bloomberg.net, Rebecca Jones

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