Malfetto is the name for a person that has survived the blood fever, but was left with a physical mark. Examples of this are strange markings resembling birth marks on the skin or different hair/eye color. The people of the Sunlands treat the malfettos as links to the gods and often keeps them in temples. In the Sealands, they are treated as second class citizens and are often killed with their murderers having few consequences, if any. In the Skylands, which was not as strongly affected by the blood fever, they are instead revered and protected. This has put the two lands at odds many times.
In Italian, mal means ill, and fetto means effect, thus making the word malfetto, once translated, "ill effect". This is true to what malfettos actually are—an 'ill effect' to a family's name, and an effect of a disease.