Chicago ? McDonald’s Corp. on Friday reported sharp sales gains for January, a full month after the first case of mad cow disease emerged in the United States.

The hamburger giant was boosted by its new “I’m Lovin’ It” campaign, extended hours and revamped menu items, as well as the weak dollar.

Sales from the more than 30,000 McDonald’s restaurants worldwide were up 19 percent from January 2003.

The new figures showed that U.S. consumers didn’t stay away from the burger chain despite news in December that a Holstein in Washington state was infected with mad cow disease.

Sales at restaurants open more than a year, considered a key indicator of McDonald’s health, rose 10 percent due to gains of 13.4 percent in the United States and 6.5 percent in Europe.

McDonald’s stock rose 46 cents to $27.16 per share on Friday on the New York Stock Exchange, its highest level since July 2002.