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Regular donors have been called in to give blood. That's because at the Blood Centers of the Pacific, blood donations are down 13 percent since the beginning of the year.
"We are seeing fewer donors being able to donate, so we are seeing a little bit of a drop in our blood supply," said Kevin Adler of the Blood Centers of the Pacific.
"We seem to be at the peak of the flu activity right now, "Dr. Cora Hoover of the San Francisco Department of Public Health.
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When you fill out the blood donation questionnaire, you're asked 'are you feeling healthy?'
"If you're not feeling healthy, you're not a prime candidate to donate blood," said Alder
So the high number of people sick with the flu is having an impact on donations.
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Kaitlyn Arnett discovered there was a need for blood and platelet donors and quickly made an appointment.
"In doing my research for where to go in San Francisco and the Bay Area, I realized there was a need, it said it on their website," said Arnett.
The American Red Cross is desperate for donations.
The Red Cross reports because of the recent storms back East, there were 28,000 fewer donations than what was needed in November and December.
And the Bay Area can't send blood there, if we have a shortfall here.
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