WASHINGTON — Officials at Landstuhl Regional Medical Center confirmed two cases of the H1N1 influenza, or swine flu, on Friday, and said four others may be infected as well.

The six patients — all military members — were sharing a common area at the hospital, according to officials from the center’s Infectious Disease Laboratory. The two confirmed cases are the first among U.S. military personnel in Europe.

In a statement, Preventive Medicine Consultant Col. Evelyn Barraza said there is no indication of additional cases outside of those six troops. Each patient has responded to treatment with Tamiflu, officials said.

With the exception of a patient who arrived from Italy on May 26, none had traveled outside of Germany in the past two weeks, officials said.

On Friday, President Barack Obama visited the medical center and met with troops recovering from combat injuries there. But hospital spokesman Steve Davis said the six involved with the H1N1 virus were not among those he met.

“They were moved to another part of the hospital when it was first recognized,” he said. “So they’ve been out of [that section] for about three days.”

Landstuhl officials are not identifying the swine flu patients, but said they are not at the center because of combat injuries. Each is expected to make a full recovery.

In April, Marine Corps Commandant Gen. James Conway told reporters that a Marine at Twentynine Palms had been quarantined for swine flu. The Marine’s roommate was also quarantined, and more than 30 other Marines were put under observation and given Tamiflu, Conway said.

Barraza said the cases are no reason for public alarm, but military personnel in Germany should continue to follow preventive guidelines recommended by the Centers for Disease Control and Prevention to prevent the spread of the influenza virus.

That includes sanitary practices like hand washing and seeking medical advice if symptoms of flu arise.

Reporter Jeff Schogol contributed to this story.