WHITEHOUSE STATION, N.J.--(BUSINESS WIRE)--May 1, 2006--As part of its commitment to helping uninsured Americans gain access to their medicines, Merck & Co., Inc. is serving as a national sponsor of this week's Cover the Uninsured Week, the largest campaign in history to focus attention on the need to secure health coverage for Americans. Nearly 46 million Americans - or 15 percent of the U.S. population - currently lack health coverage.