The suspected fatal case of the virus A/H1N1 was reported by the Central Hospital in Västerås.
The man was seriously ill with cancer and had undergone chemotherapy. He arrived at the hospital on Monday and said he was not feeling well. Doctors then discovered he had fever and signs of pneumonia.
He was quickly transferred to an intensive care ward, where his condition rapidly deteriorated. He was treated with artificial lungs but died on Thursday morning.
“Despite a massive intensive care operation we were unable to save his life,” doctor Stefan Ström told reporters at an afternoon press conference.
Shortly before his death, staff at the hospital learned that the man had type A influenza. Tests results are expected on Friday and will confirm whether the 55-year-old was suffering from swine flu.
If the virus is confirmed, the man will be Sweden’s second swine flu victim, following the death of a 40-year-old man in Uppsala last Friday.
The first victim was within one of the specified risk groups, but the authorities have not revealed the category out of respect for the man’s family. The man had experienced normal flu-like symptoms, such as pain in the body and throat.