Simile: Town
In an early simile the narrator depicts the town and the startling disruption of plague: "you must picture the consternation of our little town, hitherto so tranquil, and now, out of the blue, shaken to its core, like a quite healthy man who all of a sudden feels his temperature shoot up and the blood seething like wildfire in his veins" (16). The simile is very effective not only because it uses the imagery of health and sickness, relevant to the plague itself, but also because it is an image that allows the reader to see just how scary and disconcerting the swift passage from normal to abnormal, from healthy to sick, from unfettered to beleaguered, actually is.
Metaphor: Plague
Understandably, the townspeople can barely fathom what is happening to them as the plague begins its subtly menacing path through their lives. The narrator notes, "we tell ourselves that pestilence is a mere bogy of the mind, a bad dream that will pass away" (37). In this metaphor, we get the sense that the people wish to think they're making up how bad this plague is, or that it is merely a bad dream that will vanish upon waking. They think the plague is ephemeral or overblown, and this is the only way they can deal with it for a time.
Metaphor: Life
Rieux uses this metaphor to describe the tenuousness of life for one stricken by the plague: "Yes, in conclusion, the patient's life hung on a thread, and three people out of four...were too impatient not to make the very slight movement that snapped the thread" (39). The image is one of a person barely hanging on—a thread is an insubstantial, weak thing, and it would not hold anyone aloft for very long, if at all. The afflicted person, because they are only human, can hardly resist moving and breaking the thread, thus demonstrating how terribly fatal this disease is.
Simile: The Past
The narrator explains the strangeness of time during the plague, suggesting that people have "the irrational longing to hark back to the past or else to speed up the march of time, and those keen shafts of memory that stung like fire" (71). With this simile, he indicates that people, stuck in a hellish present, end up wishing they were back in some past in which plague did not exist, but these ruminations are exquisitely painful because of the sharp contrast with the present moment.
Metaphor: Incarceration
The gates are closed to the people of Oran and they are now hemmed in by walls and the sky above. The narrator writes of their realization of their fetters: "But, now they had abruptly become aware that they were undergoing a sort of incarceration under that blue dome of sky" (100). The metaphor of imprisonment is a potent one, for it shows just how small, restrictive, and oppressive life is now.