More than 40 people have been hospitalised in Las Vegas since Friday, as a heatwave blistered parts of the US.
Las Vegas fire and rescue spokesman Tim Szymanski said: "We will probably start to see a rise in calls Sunday and Monday as the event prolongs.
"People's bodies will be more agitated the longer the event lasts and people may require medical assistance".
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Colo became a mother of three, grandmother of 16, great-grandmother of 12 and great-great-grandmother of three.
The district's director of homeland security has said officials are planning for 800,000 to 900,000 people to attend the ceremony.
The Supreme Court is set to decide on whether disabled travellers are legally entitled to have priority use of wheelchair spaces on buses.