As far as first sentences go, I like the fact that you started with something interesting. Is it cliche? Not necessarily - it really depends on what happens further along in the story. You do have a problem with the execution, though. Since this is a short story you have to learn to economize your words to make them all count. Every word should have a reason for being there. Try this, for example:
In 1987, six people were found dead in a New York alleyway. All six were covered in green pustules that spurted steaming hot puss when they were touched by the medical examiner's fingers.