"CALEXICO, CALIF. — As the relentless wind stirs up piles of dust and dirt and creates a gigantic funnel of haze in the vast, sweltering Imperial Valley, children like Marco Cisneros battle to breathe."
"Marco wheezes and coughs and reaches desperately for his inhaler, but the medication doesn't always give him the relief he needs. Often, his mother has to call 911.
Since being diagnosed with severe asthma six years ago, Marco, who lives in this border town east of San Diego, has visited the hospital nearly 50 times. He has been airlifted on several occasions. The illness has affected much of his childhood, preventing him from playing sports, going to friends' houses and attending school for days at a time. Blowing out the candles on his 8th-birthday cake earlier this year, Marco had just one wish: 'I just want to run.'"