SAN ANTONIO -

With six kids, 16 grandchildren and 11 great-grandchildren, Maria Garcia has more then enough reason to stay healthy.

So when she came down with a rare autoimmune disorder that caused her blood count and platelet count to drop, her family was very concerned.

Garcia was hospitalized and needed blood immediately.

"When you're in the hospital, you're scared because of your illness, and you need this blood. I had no idea of all the people that give blood," Garcia said.

Now, Garcia is out of the hospital and doing well.

She's also become the face of a new campaign the South Texas Blood and Tissue Center is launching called "Give of Yourself."

The timing couldn't be better with the blood supply particularly low.

"Twenty-three percent of our donors that come to donate throughout the year come from high schools and colleges and during the summer, those groups are not necessarily in session," President and COO of the South Texas Blood and Tissue Center Mary Beth Fisk said.

And she says while all donations are appreciated, donors should know the blood only lasts for 42 days. Thusly, constantly replenishing the supply is a must.

All blood types are needed, but those people with O Negative blood are especially needed.

O Negative, the universal donor, can be given to anyone.

"It could happen to us or one of our loved ones that are going to need blood so we all need to donate," Garcia said.

To find out how to donate blood, visit http://www.bloodntissue.org/Locations.aspx or call the South Texas Blood and Tissue Center at 210-731-5555 or free at 800-292-5534.

You can also stop by their main center at 6211 IH-10 West San Antonio, TX 78201.