The patient is an Illinois man who had close contact with the country's first confirmed case of MERS virus infection in Indiana and "probably got the virus from the Indiana patient," the CDC said in a statement.

　　The Illinois resident "did not seek or require medical care" and "is reported to be feeling well" at this time but as part of the MERS virus infection follow-up investigation of the first case, local health officials have monitored his health daily since May 3, the CDC said.

　　U.S. reports third case of MERS virus

　　It said that the Illinois resident, who has no recent history of travel outside the United States, met with the Indiana patient on two occasions shortly before the latter was identified as having had MERS virus infection.

　　The Illinois man tested positive for the MERS virus Friday night, the CDC added.

　　The first U.S. MERS case is a U.S. resident who had traveled back from Saudi Arabia and was admitted to an Indiana hospital on April 28. He was confirmed to have MERS virus infection on May 2, and has since been released from the hospital.

　　A second U.S. imported case of MERS virus infection was confirmed on May 11 on a 44-year-old man who also came to the U.S. from Saudi Arabia. This patient is currently hospitalized in Florida and doing well, the CDC said.

　　The MERS is a virus that is new to humans and was first reported in Saudi Arabia in 2012. As of May 16, there have been 572 laboratory-confirmed cases of MERS virus infection in 15 countries with 173 deaths, the CDC said.

　　Most of these people developed severe acute respiratory illness, with fever, cough, and shortness of breath. Officials do not know where the virus came from or exactly how it spreads. There is no available vaccine or specific treatment recommended for the virus.（本文由在线英语听力室整理编辑）