But then investigators learned they had participated in blood-shedding religious rituals — cutting or whipping themselves — in Iraq, Pakistan, India and the United Kingdom. The men were infected with human T-cell leukemia virus type 1, known as HTLV-1. The mystery was solved when Dhasmana noticed scars on the back of one man, leading to questions that revealed all 10 men had participated in religious self-flagellation. One ritual involves striking the forehead with a knife and then passing it along to other men. But that is inadequate to prevent spread of HTLV-1, Dhasmana said.

Source: Fox News March 13, 2019 16:59 UTC