It's worked so well that the regional hospital in Cluj-Napoca actually ran out of fridge space for blood bags yesterday, Festival PR manager Stefana Guirgiu told CNBC on the phone.
"We're seeing if we can find a fridge that has the right specifications to hold more bags," Guirgiu said.
Over 500 people had donated as of Tuesday. Over 300 people were turned away from the Cluj-Napoca hospital but were asked to return later in the week.
Guirgiu said the "Pay with Blood" campaign was initially the festival's brainchild, but they easily brought Romania's National Institute of Blood Transfusion (NIBT) on board. It was a way to not only do something to improve the country, she said, but it actually was able to incorporate a famous Transylvanian fairy tale — namely, Dracula. He's become a main facet of the campaigns promotional materials.
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Romania is currently one of the worst European countries when it comes to active blood donors, according to NIBT statistics. Only 1.7 percent of Romania's nearly 20 million strong-population donates blood each year. In comparison, the U.K. sees a near-three percent active donor rate, according to the country's National Health Service.
Despite the campaign's success, Guirgiu insisted festival organizers aren't worried about losing cash and says the campaign isn't considered a major investment. The festival is currently being funded by the local authorities and corporate sponsors, including McDonalds, KFC and Durex.
"We're very proud of this campaign. It's mobilized lots of youngsters," Guirgiu said.
The four-day music festival will run from July 30 to August 2.