By Karen Kaplan, Los Angeles Times

The U.S. Centers for Disease Control and Prevention have identified an Illinois man who appears to be the first homegrown case of MERS in the United States.

The man does not have an active case of Middle East respiratory syndrome, CDC officials said Saturday. But blood tests show that his immune system has made antibodies to fight the MERS coronavirus — an indication that he has been infected.

Unlike the two other U.S. residents who have been diagnosed with MERS — one in Indiana and one in Florida — the Illinois man has not traveled to the Middle East, where the virus first appeared in 2012. However, he met with the Indiana patient twice and had close contact with him during those visits, according to the CDC.

The Illinois man, whose identity was not released, was never sick enough to seek medical care. Health officials tested him as part of their investigation into all the known contacts of the Indiana patient, a health-care worker who returned from Saudi Arabia four days before he was admitted to Community Hospital in Munster, Ind., on April 28.

Health officials will reach out to people who have been in close contact with the Illinois man to “notify, test and monitor” them, according to the CDC.

“It’s possible that as the investigation continues others may also test positive for MERS-CoV infection but not get sick,” Dr. David Swerdlow, the epidemiologist in charge of the CDC’s MERS response, said in a statement.

Local health officials have been keeping tabs on the Illinois man since May 3. His blood test results showing MERS antibodies were reported to the CDC on Friday night.

As of Saturday, the Illinois man was “feeling well,” the CDC said.

So was the Indiana patient, who was identified May 2 as the first case of MERS in the U.S. He has been discharged from the Munster hospital and is “fully recovered,” according to the CDC.

The Florida patient is also a health-care worker who traveled from Saudi Arabia to Orlando to visit relatives there. He began to experience flulike symptoms on a plane from Jidda to London on May 1. He was admitted to a hospital May 8, where he is isolated and “doing well,” the CDC says.

There is no link between the Indiana and Florida patients.

At this time, there is no need for Americans wishing to visit the Arabian Peninsula to cancel their plans, the CDC says. Travelers should monitor their health while overseas and once they return, according to the agency.

“This latest development does not change CDC’s current recommendations to prevent the spread of MERS,” Swerdlow said. “If new information is learned that requires us to change our prevention recommendations, we can do so.”

Photo via Flickr