Costa Rica's President Oscar Arias, a Nobel Peace Prize winner, has contracted swine flu, becoming the world's first known leader to have fallen ill with the virus. Arias, 68, has a mild case of the virus for which he tested positive Tuesday after feeling unwell at the weekend, the government said. Arias is at home and plans to do some work from there. “Apart from the fever and a soar throat, I feel well and in good shape to carry out my work by telecommuting. I expect to return to all my duties on Monday,” he said in a statement. Arias suffers from asthma. While the vast majority of swine flu cases have not been serious, infected people who have other medical conditions are most susceptible to complications. “The tests ... show that there is no other complication,” Information Minister Mayi Antillon said. During his first four-year term Arias was awarded the Nobel Peace Prize in 1987 for negotiating peace accords which helped bring an end to Central America's many military conflicts.