Turk puts on weight, and is teased by Carla, which bothers him. Meanwhile, as J.D. and Nurse Roberts check a patient's Hepatitis B viral load, J.D. is accidentally stuck by the blood-filled needle. J.D. fears he has been infected, and has tests done. While some people are supportive of him, others, like Dr. Kelso, are not as helpful. The Janitor mocks him in his usual tone. Elliot spends the night with Sean Kelly, prompting teasing from others in the hospital. Carla tries to reassure Turk that she meant nothing by her joke about his weight, and says that no doctor in the hospital is in shape. Her assuring words are undermined when a very fit Dr. Cox walks by.

J.D. treats four doctors who scare him by telling stories of their colleagues getting infected by their patients. Elliot and Sean have a discussion on their sex life. Intrigued by Dr. Cox's fitness, Turk looks to him for advice on how to stay in shape. Dr. Cox then mocks Turk by showing him his "future", then invites him to work out with him. At rounds, Elliot screws up her questions. She fears her relationship with Sean is the cause. J.D. becomes increasingly paranoid, knowing that he might have Hepatitis B. His fears are extinguished when the tests reveal he is healthy. Despite his negative test, J.D. is still frightened by the idea of being infected. Elliot becomes increasingly agitated at Sean, even though he has no idea why she is angry. J.D.'s fear of disease causes him to lose the respect of his peers. Carla, feeling ignored by Turk, asks him to spend time with her. Elliot apologizes to Sean over her outbursts at him, then realizes that their relationship might not be working, and breaks up with Sean. Dr. Cox refuses to give J.D. back the meningitis patient he traded to him. J.D. realizes that Dr. Cox wanted him to get over his false phobia himself.

Read more: http://scrubs.wikia.com/wiki/My_Sacrificial_Clam#ixzz14hPaM9eg