Long-term Clinical Prognosis of Human Infections with Avian Influenza A(H7N9) Viruses in China after Hospitalization

Background: Mainland China has experienced five epidemics of human cases of avian influenza A(H7N9) virus infection since 2013. We conducted a prospective study to assess long-term clinical, pulmonary function testing, and chest computed tomography (CT) imaging findings after patients were discharged from hospital. Methods: A(H7N9) survivors in five provinces and one municipality underwent follow-up visits from August 2013 to September 2018, at three, six, and 12 months after illness onset, and a subset was also assessed at 18 and 64 months after onset. Thirteen patients were enrolled from the first A(H7N9) epidemic in 2013, 36 from the 2013-2014 second epidemic, and 12 from the 2016-2017 fifth epidemic. At each visit, A(H7N9) survivors received a medical examination, including the mMRC (modified Medical Research Council) dyspnea scale assessment, chest auscultation, pulmonary function testing and chest CT scans. Findings: The median age of 61 A(H7N9) survivors was 50 years. The cumulative rate of pulmonary dysfunction was 38.5% and 78.2% for chest CT scan abnormalities at the end of follow-up. Restrictive ventilation dysfunction was common during follow-up. Mild dyspnea was documented at three to 12-month follow-up visits. Interpretation: Patients who survived severe illness from A(H7N9) virus infection had evidence of persistent lung damage and long-term pulmonary dysfunction. (C) 2020 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/)