Dr. William Schaffner, chairman of preventive medicine at Vanderbilt University Medical Center in Nashville, Tenn, said there are several reasons the new pope could have had his lung removed about six decades ago, ABC News reports.
He said that Pope Francis could have had tuberculosis, or he could have had a complication of whooping cough, or pertussis.
According to Dr. Schaffner, the Pope could also have had pneumonia and developed complications, or he could have been born with a congenital lung defect that got infected.
Although these infections would have been more common in a middle-aged person than a teenager, Schaffner said they're the most likely possibilities given the limited information about the lung removal, the report said.
According to the report, when asked whether a person can survive with one lung, Schaffner said, 'people can easily live' as lungs are redundant.