A STRONG TREMOR measuring 5.5 degrees on the open-ended Richter scale jolted the Iranian town of Tabas and nearby areas Monday. There were no immediate reports of casualties or damage. . . . BORIS YELTSIN, the Russian republic leader injured in an auto accident last month, was ordered to stay home Tuesday by his doctors after a brief appearance in parliament. . . . THE THIRD GAME of the world chess championship between champion Garry Kasparov and Anatoly Karpov was suspended Monday with neither player showing a clear advantage. . . . A U.S. COAST GUARD cutter intercepted a 40-foot sailboat packed with 91 Haitians and returned them to Haiti on Monday.