Given the task definition and input, reply with output. In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.

To investigate the long-term effects of mild H1N1 influenza infection on the pulmonary function of a cohort of patients. Forty-eight patients, all diagnosed with influenza A virus subtype H1N1 in 2009, were retrospectively included in this study. Each patient in the study was monitored for 11-13 months by standard pulmonary function examination. The examination included monitoring respiratory tract infection symptoms (cough, expectoration or gasping) and vital signs. Long-term changes in symptoms and changes in vital signs were correlated back to and compared with the severity of the initial H1N1 influenza infection.
Pulmonary Function and Clinical Manifestations of Patients Infected with Mild Influenza A Virus Subtype H1N1: A One-Year Follow-Up