Most of the 263 deaths in the United States

Laboratory tests confirmed late Thursday that the man, who was hospitalized at the medical center on July 3, had the H1N1 flu.

The man had a serious underlying chronic medical condition that makes it complicated to conclusively state that the flu virus caused his death, according to Dr. MaryAnn Curl, chief of staff at the medical center.

Additional tests are pending that may help infectious disease physicians make a determination on whether the H1N1 flu was the cause of death. The man's family has declined to have an autopsy performed.

“I can't say conclusively that H1N1 was the cause of death, nor can I rule it out,” Curl said. “It will definitely be a contributor.”

The veteran's death is the first death possibly associated with the H1N1 virus at a VA medical center in the region, Curl said, although there have been a small number of deaths associated with the swine flu at VA facilities around the country.

Four deaths in North Carolina have been linked to the virus, including two in Guilford County and one each in Carteret and Wilson counties.

Curl would not elaborate on the specifics of the man's underlying chronic medical condition, but she said that it was a condition that would make him more susceptible to complications from the H1N1 or seasonal flu.

Most of the 263 deaths in the United States associated with the virus have been in people with underlying chronic conditions.

“This veteran had something that would particularly pose an enhanced vulnerability with flu,” Curl said.

The man came to the VA Medical Center with symptoms that were not typical of flu, and doctors did not suspect that the man had the virus initially, Curl said. She said that the man's health deteriorated during the time he was hospitalized, eventually causing him to be put on a ventilator.

When the man's treatment did not appear to be working, doctors decided to send samples to the state lab for testing for the H1N1 flu. Samples were sent to the laboratory on July 10.