Lungs infected with Hepatitis-C are safe for transplant.
Doctors in Canada say donor lungs from people with Hepatitis-C have been successfully transplanted into ten patients.
Eight have already tested negative for Hepatitis-C after taking anti-viral drugs after surgery.
Experts say accepting Hepatitis-C positive donors would increase the number of available lungs by one-thousand a year in North America.
All ten patients have recovered fully from their transplant surgery.