Officials at the Red Cross say they are asking people to wait 28 days to donate if they've been to certain regions with the Zika virus.
Those places include Mexico, the Caribbean, Central and South America.
And if a donor develops signs of a Zika virus infection within two weeks of donating, the Red Cross wants to be notified.
The organization says the risk of spreading the virus through blood donation is small, but it wants to be sure the supply is safe.
Meanwhile, the FDA says it is still considering making changes to its policy.
Red Cross defers donations to protect supplies from Zika virus
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