A Journal of the Plague Year is a novel by Daniel Defoe, first published in March 1722. This novel is an account of one man's experiences of the year 1665, in which the Great Plague or the bubonic plague struck the city of London. The book is told somewhat chronologically, though without sections or chapter headings. Presented as an eyewitness account of the events at the time, it was written in the years just prior to the book's first publication in March 1722. Defoe was only five years old in 1665. In the book, Defoe goes to great pains to achieve an effect of verisimilitude, identifying specific neighborhoods, streets, and even houses in which events took place. Additionally, it provides tables of casualty figures and discusses the credibility of various accounts and anecdotes received by the narrator. The novel is often compared to the actual, contemporary accounts of the plague in the diary of Samuel Pepys. Defoe's account, which appears to include much research, is far more systematic and detailed than Pepys's first-person account. The Great Plague killed an estimated 100,000 people, almost a quarter of London's population in 18 months. The plague was caused by the Yersinia pestis bacterium, which is usually transmitted through the bite of an infected rat flea.