Kyoto University Hospital says it has carried out the world's first lung transplant from living donors to treat severe lung damage caused by the coronavirus.
Professor Date Hiroshi, the director of the thoracic surgery department, held a news conference on Thursday with other staff members.
The hospital says a woman who lives in the Kansai region underwent the nearly 11-hour surgery on Wednesday.
It says the patient had developed severe pneumonia after she was infected with the coronavirus late last year.
She was treated using ECMO machines that replace the functions of the heart and lungs, and eventually tested negative for the virus.
But she lost most of her lung function due to fibrosis, and there was no prospect of recovery.
Surgeons transplanted lung sections from the woman's husband and son after they offered to be donors.
The hospital says the woman is now being treated in the intensive care unit. The doctors say if the patient continues to recover, she is likely to be fully rehabilitated in three months. They say her husband and son are also doing well.
The hospital says the woman is the world's first former COVID-19 patient to receive a lung transplant from living donors. Date says that lung transplants will be a promising treatment option for people suffering serious aftereffects after contracting the coronavirus.