I am legend - R. Matheson

The story takes place between January 1976 and January 1979 in Southern California. The novel opens with the monotony and horror of the daily life of the protagonist, Robert Neville. Neville is apparently the only survivor of an apocalypse caused by a pandemic of bacteria, the symptoms of which are similar to vampirism. He spends every day repairing his house, boarding up windows, stringing and hanging garlic, disposing of vampires' corpses on his lawn and going out to gather any additional supplies needed for hunting and killing more vampires.
Much of the story is devoted to Neville's struggles to understand the plague that has infected everyone around him, and the novel details the progress of his discoveries.
One day a dog appears in the neighborhood. Neville spends weeks trying to win its trust and domesticate it. He eventually traps the terrified dog and wins it over, but it dies from the vampire infection a week later.
As the story progresses, it is revealed that some infected people have discovered a means to hold the disease at bay. However, the "still living" people appear no different from the true vampire during the day while both are immobilized in sleep. Thus, along with the vampires, Neville kills the still living people. He becomes a source of terror to the still living, since he can go around in daylight (which they can only do for a short length of time using a special pill) and kill them while they sleep.
They send a still living woman named Ruth to spy on Neville, and they replicate Neville's relationship with the dog. Ruth, terrified of Neville at first sight, goes against her role of spying on him and runs away. Rather than spend weeks trying to win her over, he attacks her and drags her back to his house. Eventually Neville performs a blood test on her, revealing her true nature to him right before she knocks him out with a mallet. Ruth leaves a note telling him about the group of people like her, explaining that she was sent to spy and how monstrous he appears to them. Months later, the still living people attack, injuring Neville, but taking him alive so that he can be executed in front of everyone in the new society (which Neville finds very primitive).
Before he can be executed, Ruth provides him with an envelope of pills. Neville takes the pills to commit suicide before the still living execute him. As he dies he reflects on how the new society of the living infected regards him as a monster. Just as vampires were regarded as legendary monsters that preyed on the vulnerable humans in their beds, Neville has become a mythical figure that kills both vampires and the infected living while they are sleeping. He becomes a legend as the vampires once were, hence the title "I Am Legend".

Influences
I Am Legend influenced the vampire genre and popularized the fictional concept of a worldwide apocalypse due to a disease. Although classified as a vampire story and referred to as "the first modern vampire novel. Legend made an impression on the zombie genre by way of film director George A. Romero. Romero has acknowledged the influence of the novel and its 1964 adaptation on his 1968 film Night of the Living Dead. Critics have also picked up on similarities between Night and Last Man on Earth.[5][6]
Stephen King said, "without Richard Matheson I wouldn’t be around."[7] Some film critics have noted that the 2002 British film 28 Days Later and its sequel 28 Weeks Later, which feature a rabies-like plague that ravages Great Britain, are similar to the scenario in I Am Legend.[8] The recasting of undead creatures as disease victims is also comparable to recent zombie media such as the Resident Evil series, the Blade trilogy, and the 1984 B movie Night of the Comet.
A straight-to-DVD film by The Asylum called I Am Omega was released at the same time as the 2007 film I Am Legend.