Hospital patients who receive a transfusion with older blood are more likely to face health problems, a study finds.

Currently, the Food and Drug Administration allows for blood to be stored for 42 days before being discarded, Reuters reported.

But, researchers at Cooper University Hospital in Camden, N.J., found patients given transfusions of blood stored 29 days or longer are twice as likely to get a hospital-acquired infection.

"We're not talking about hepatitis, HIV or other things that are transmitted in the transfused blood, but an increased susceptibility to infection as a result of the transfusion," Dr. David Gerber of Cooper University Hospital, one of the researchers, told Reuters.

"There are significant policy implications for this. Transfusion is still an important medical practice," Gerber added.

The average age of blood used in U.S. transfusions is around 17 days, according to the researchers.

The findings were presented at a meeting of the American College of Chest Physicians.

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