The spots
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"The Spots" was the nickname given to a serious medical condition suffered by many Tauron people during wartime. Supply lines were often cut off during armed conflict, and vitamin-rich foodstuffs such as beef liver were unavailable. This lack of nutrition caused victims to bleed from their mucous membranes, develop spotted skin due to collagen breakdown, and eventually death (The Caprican).
This condition gave rise to the perjorative term "dirt eater."