American beef is back in the Japanese market and slated to return to South Korea soon. But for America's beef exporters, who lost two of their three largest markets in 2003 after a few cases of mad cow disease were discovered in the United States, it is going to be an uphill struggle to rebuild their north Asian business. 

Despite consumer fears in north Asia about possible bovine spongiform encephalopathy, more commonly known as mad cow disease, American beef is returning to shops and restaurants in this region with ceremonial flourish.

Staff at Tokyo's popular Yoshinoya restaurant chain welcome patrons back to sample dishes made with American beef. Some diners waited as long as 12 hours to make sure they would get a taste - as supplies are limited for now.

Ambassador Thomas Schieffer has been heavily promoting U.S. beef to help American exporters rebuild their nearly $1.5-billion annual business in Japan.

The ambassador, leaving another beef promotional lunch in downtown Tokyo, joked that his cholesterol count must have soared in recent days after eating American beef for nearly every meal. But he says what is important is Japan's appetite for U.S. meat.

"The real issue here is whether the Japanese consumer will come back to American beef and I think you have seen that they are going to do that," he said.

After intense negotiations, Japan agreed this month to accept meat from specially certified exporters processing U.S. cattle younger than 21 months.

The international standard age for cattle is 30 months to ensure protection against tainted beef from animals with mad cow disease. 

Meanwhile in South Korea, U.S. boneless beef imports are due to resume within weeks, pending resolution of some minor disagreements.

Mad cow disease is a degenerative nerve disorder found in cattle that was first reported in herds in Britain 20 years ago. In 1996, there was global concern when scientists found that eating beef products from infected cows may cause a similar fatal brain disease in humans - a variant of Creutzfeldt-Jakob Disease.

The U.S. Centers for Disease Control says in the past 10 years there have been a total of 196 cases of the human illness in 11 countries. The majority of the patients have been in Britain. One person has been reported sick in Japan.