CNN reported insulin pens intended for individual use may have been used for more than one patient at the Veterans Affairs Western New York Healthcare System.
The memo, sent from U.S. Rep. Brian Higgins, D-N.Y., to Congress, said the chance patients were exposed to the hepatitis viruses and human immunodeficiency virus is very small.
CNN said all those affected were notified and will have the chance to talk to a healthcare professional.
"Beyond the fact that the error occurred at all, most concerning was the length of time it took the Buffalo VA to catch the error -- over two years, as well as the three-month delay in informing patients who may have been exposed," Higgins wrote in the memo.
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