Another good book would be Peeps by Scott Westerfield. It's not as good as Twilight but itas interesting, i enjoyed.
As for the plot:(It's better than it sounds) (Spoiler alert)
Peeps is a 2005 novel by Scott Westerfeld revolving around a parasite which causes people to become cannibalistic and become repelled by that which they once loved; it is the basis for many myths, mainly vampirism, but also lycanthropy, zombies, and others. The parasite changes the physiology of the affected person, granting him or her almost "superhuman" powers, such as extreme night vision (the protagonist claims that he has to tape over the dimly lit clock on his DVD player in order to sleep and being able to read fine print by starlight), the ability to climb nearly smooth vertical surfaces, and increased strength. However, according to the protagonist Cal Thompson, these feats are nothing more than the body being able to continuously sustain itself at the limits of exertion, comparable to the adrenaline rush a mother gets when her child is in danger. Every other chapter expounds upon various real life parasites.
Things get more complicated for the hero as time goes on. Soon he finds himself in love with Lacey (nicknamed Lace), a girl he can never have, and a possible new vector of the parasite.
He will soon discover that there is something much bigger than a parasite that will wreak havoc over humankind. Along with Lace, he will have to brave dangers set in the dark underground of New York subways and tunnels, possibly to save mankind and prove that parasites really do rule the earth. Cal must also track down Morgan, the woman who gave him the parasite.
The end of the world that begins in "Peeps" continues in The Last Days
Cal Thompson - The protagonist in the novel, and is explained as a "carrier" of the parasite. His body contains the parasite that in most people causes dementia, cannibalism, and other vampiric side effects. Cal gains all of the advantages, without suffering from the dementia. It is transmitted through almost any bodily fluid, and he is now a "hunter" in an ancient (dating to colonial times in America) society known as the Nightwatch. He is charged with tracking down and capturing people he has inadvertently afflicted with the disease. He is 19 years of age, and was first infected 1 year ago by a mysterious girl named Morgan.
Lace (Lacey) - Met Cal Thompson randomly in the elevator in her apartment building. Gets pulled along in the events of Cal's life and duties as a member of the Nightwatch.
Morgan - Cal's progenitor whom he met randomly 1 year ago at Dick's Bar
Hope i could help!