The heat makes people who are sick even sicker and that is especially noticeable in people with asthma.

Delores McClendon has been in the hospital since the last heat wave. She lives in a west Philadelphia rowhome and can't afford air conditioning on the bottom floor. She knows that is what caused her asthma and other respiratory problems to get worse. She had to be rushed to hospital emergency department.

"It was horrible. I just was scared. I thought I was going to breathe my last breath. I didn't know what was going on," McClendon said.

McClendon is one of many people whose breathing problems are intensified by the extreme weather.

"Along with the heat and humidity in Philadelphia is a very high mold spore count and a lot of asthmatics are allergic to them," said Dr. James Zangrilli, a pulmonologist at Thomas Jefferson University Hospital.

Zangrilli said that all those conditions could worsen an asthma attack, shutting down an asthmatics' airways so they don't get enough air.

McClendon is still on oxygen, but she is already on the mend.

"I feel a lot better. There's no wheezing. I feel a lot better since I've been here," McClendon said.

Zangrilli said that if people are reaching for their rescue inhalers a lot, they should tell their doctors because it means their asthma is getting worse.