What is "camillians"

The Camillians or Clerics Regular, Ministers to the Sick are a Roman Catholic religious order, founded in 1582 by St. Camillus de Lellis (1550-1614). A large red cross was chosen by the founder as the distinguishing badge for the members of the Order to wear upon their black cassocks, which was later adopted as the international symbol of medical care. The founder taught his volunteers that the "hospital was a house of God, a garden where the voices of the sick were music from heaven". They use the postnominal initials of M.I.