"At Oran, as elsewhere, for the lack of time and thinking, people have to love one another without knowing much about it."Even through the illness, the population of Oran is striving to be happy. They keep living, which is in direct correlation to the meaning of 'absurdism.' The population keeps rolling their stones up their hills.
Humans may be rats in some cases, but we seem to feel more than the average rat. We take our fears and turn them into strength in one way or another to fight nihilistic tendencies. Camus had a crap early life, but he made the most of what he had. And, he died as absurdly as he began. The Plague is absurd in its comparison to rats. But, if we think about it, is this comparison really absurd? When we are afraid and act on fear, we may not be any better than rats.
Below is a video calling Camus an absurd hero: