John Milton's Paradise Lost (1667), the great English biblical epic, includes extended passages on disease, bodily corruption, and parasitic infestation as consequences of the Fall. In Book XI, the Archangel Michael shows Adam a vision of the diseases that will afflict humanity after expulsion from Eden, including conditions consistent with parasitic infection — loathsome, crawling afflictions of the flesh. Milton completed Paradise Lost while blind, dictating to his daughters, and his engagement with bodily suffering and corruption was intensely personal as well as theological.

Milton's deployment of parasitic disease and bodily corruption in Paradise Lost as consequences of original sin gave the parasite a theological significance it had been building toward since the biblical plagues. For Milton, the louse, the worm, and the disease-carrying insect are not accidental features of the fallen world but direct consequences of human sin — a position that shaped Protestant attitudes to disease and parasites for generations. Subsequent poets who engaged with the theology of disease and nature drew on Milton's framework even when they contested it.