A 50-year-old man underwent a successful double lung transplant last year in Edmonton even though he was infected with the H1N1 virus at the time of the surgery, doctors reported this month.

The man was short of breath with end-stage lung disease at the time that he was admitted for a double lung transplant.

Transplant patients receive drugs to suppress their immune system to prevent rejection of the transplanted organs, which can increase their risk for infections like flu.

When he was admitted, he had flu-like symptoms, including malaise. As a safety measure, a swab was taken, and he was started on antiviral treatment.

Just after the operation, his swab came back positive for H1N1, said Dr. Mohammed Al Aklabi of the cardiac surgery division at the University of Alberta in Edmonton.

Al Akabi and his colleagues reported their findings in this month's issue of the Journal of Heart and Lung Transplantation.

After the surgery, two samples from the transplanted lungs were also found to be positive for the H1N1 virus, the researchers said.

"He received three-weeks of antiviral treatment post-operatively, and he had uneventful procedure with favorable outcome," the researchers wrote.

The patient had a genetic disorder known as alpha 1-antitrypsin deficiency and developed chronic obstructive pulmonary disease, or COPD, a progressive and irreversible blocking of the airway that includes emphysema and chronic bronchitis.

Studies suggested that people with asthma and COPD were among those at greatest risk for severe cases of H1N1.

Last week, Alberta researchers reported organ transplant recipients who became infected with H1N1 seemed to do better if they were treated early with antivirals.

The H1N1 virus resulted in a spectrum of illness, with symptoms ranging from mild to severe, in the transplant recipients just as it did in the general population.