The mayor says there is an urgent need for blood with donations down significantly since the pandemic began.
First Lady Chirlane McCray also donated blood along with the mayor.
Before the virus struck, blood drives at businesses, churches and other sites were the biggest source of donated blood in the New York area.
Now, blood drives have almost completely stopped.
In April alone, blood center officials point out that donations in the area it covers dwindled to 14,000. In a typical month, they would collect twice that many.
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