Transmission of mouse scrapie prions by stainless steel wire. Stainless steel wires were inserted into the brains of scrapie-infected mice for 5, 30, or 120 min, washed exhaustively, and introduced permanently into brains of indicator mice. Five minutes of contact sufficed for the wire to acquire a maximum load of infectivity, equivalent to the injection of 30 μl of 1% homogenate of the same brain. Data from ref. 73.