Disasters lure blood donors—but public drives fail

Some people in Las Vegas stood in line for more than seven hours to donate blood following the Oct. 1 mass shooting at a music festival.

This is a typical response to a disaster, according to a Washington Post article, but there is still a massive shortage of donors nationwide and blood drives run by the American Red Cross are faring worse than in previous years.

Why are people so willing to act following a disaster—whether natural or human-inflicted—but less receptive to requests from blood centers?

The Post analyzed the psychology behind this behavior in the following story: