It happens after every disaster, whether natural or human-made. Before the floods recede or the crime tape is removed, hundreds will line up to donate their blood.
Less than 24 hours after the mass shooting in Las Vegas, a line of people twisted from a blood center around several city blocks. According to one woman's tweet, it took seven hours or more to get to the front of the line. Time and time again it's the same story. When two bombs shredded scores of runners and fans at the 2103 Boston Marathon, media outlets reported that some participants who had crossed the finish line kept running — right to Massachusetts General, around the corner, to donate blood.
