Albino Body Parts

I just read a grisly article in the New York Times online about a wave of Albino murders in Tanzania. Apparently, witch doctors have been spreading the word that Albinos are good luck. A market for Albino body parts has grown in the area around Dar Es Salaam. The article reports 19 albinos have been killed in recent weeks. Why are Albinos suddenly good luck? The article also mentions that albino-killing is spreading to Kenya. I will be especially careful, as mzungu could easily be mistaken for albino, I would think.