The first reliable description of the disease known as typhus appears in 1489 during the Spanish siege of Baza against the Moors during the War of Granada (1482–1492).

These accounts include descriptions of fever; red spots over arms, back, and chest; attention deficit, progressing to delirium; and gangrenous sores and the associated smell of rotting flesh.

During the siege, the Spaniards lose three thousand men to enemy action, but an additional seventeen thousand die of typhus.