The Plague of AD251
This terrible plague ravaged the empire for 15 years and took the life of Hostilian (son of Decius, co-Augustus with Trebonianus).
The writings of Cyprian
Cyprian, Bishop of Carthage wrote about the plague, in some of his Christian writings. In "The Life and Passion of Cyprian", Pontius the Deacon tells of Cyprian's experience:
"there broke out a dreadful plague, and excessive destruction of a hateful disease invaded every house in succession of the trembling populace, carrying off day by day with abrupt attack numberless people, every one from his own house. All were shuddering, fleeing, shunning the contagion, impiously exposing their own friends, as if with the exclusion of the person who was sure to die of the plague, one could exclude death itself also. There lay about the meanwhile, over the whole city, no longer bodies, but the carcases of many, and, by the contemplation of a lot which in their turn would be theirs, demanded the pity of the passers-by for themselves."
Full text: http://www.users.drew.edu/ddoughty/Christianorigins/persecutions/cyprian.html
In "On the Mortality/Plague" (or "De mortalitate") Cyprian describes the effects of the plague and also explains to the Chrisitians that they should not be surprised that both righteous and the unrighteous are affected equally, but that they should teak heart in that they can expect a happier afterlife:
"This trial, that now the bowels, relaxed into a constant flux, discharge the bodily strength; that a fire originated in the marrow ferments into wounds of the fauces; that the intestines are shaken with a continual vomiting; that the eyes are on fire with the injected blood; that in some cases the feet or some parts of the limbs are taken off by the contagion of diseased putrefaction; that from the weakness arising by the maiming and loss of the body, either the gait is enfeebled, or the hearing is obstructed, or the sight darkened;--is profitable as a proof of faith. What a grandeur of spirit it is to struggle with all the powers of an unshaken mind against so many onsets of devastation and death! what sublimity, to stand erect amid the desolation of the human race, and not to lie prostrate with those who have no hope in God; but rather to rejoice, and to embrace the benefit of the occasion; that in thus bravely showing forth our faith, and by suffering endured, going forward to Christ by the narrow way that Christ trod, we may receive the reward of His life and faith according to His own judgment!"
See the text here: http://www.ewtn.com/library/PATRISTC/ANF5-15.TXT