Your article appears to suggest that healing of old people could be promoted by young people’s blood. Perhaps there is something to the Dracula story after all. Young people give blood for money. Anything known about the effect of transfusions on old people?

Bill Hawkins
Minneapolis, Minn.

The mice in this experiment exchanged far more blood than the comparable volume in most transfusions, which the researchers say probably wouldn’t be enough to exert the healing effect. They add that they know of no one keeping track of the ages of blood donors and recipients .—C. Brownlee
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