The action of the novel takes place in the city of Oran, beginning with the death of some rats, death which, even if initially didn’t seem to be something unusual, begins to create panic. The number of rats increases exponentially, especially towards the periphery of the city and, after so many dead animals, comes a dead man, event that alarms the doctor of the town. It seems obvious that rats are responsible for the spread of the disease and this was what people strongly believed over time.
Yet, some recent studies in London reached the conclusion that, after all, the plague was not spread by rats. As the archeologist Barney Sloane said, “the plague spread too fast for the traditional explanation of transmission by rats and fleas. It has to be person to person – there just isn’t time for the rats to be spreading it.” A recent study on this topic can be found in this article from The Guardian. Also, the fact that plague killed people in Northern Europe refutes the theory that the disease was spread by fleas. These new understanding of the disease lead the scientist to the conclusion that Plague was caused by “a viral hemorrhagic fever pandemic similar to Ebola “ and a comparison between these two diseases can be found here.