Mike Feetham , Nov 19, 2003; 07:17 p.m.
One dead pixel will not cause other pixels to "die". However, sometimes this can be a sign of a bad CCD. If you can live with one spot, and the camera is new, you may want to wait things out and see what happens.
Keep an eye on how much warranty time you have left, and look at sending it in before the warranty expires. If other problems develop, Nikon may replace the camera, instead of just fixing what's broken. Something similar happened to my 5700, and Nikon was kind enough to send me a whole new camera; shrink wrapped box and everything.
You can test the actual affected area by setting the camera on a tripod and taking a few shots in RAW format. Compare the images to see if it's one pixel, or a group. A damaged group may be a sign that something physically damaged the CCD. In this case, I would get it repaired right away.
Hope this helps!