Fatal cases of human infection with avian influenza A (H7N9) virus in Shanghai, China in 2013

Abstract

We retrospectively reviewed the medical records of 17 fatal H7N9 cases in Shanghai in 2013, analyzed clinical variables and described their clinical and epidemiologic characteristics. The median age was 73 years, and 82.4% had underlying medical conditions. The most frequent symptoms were fever (100%), followed by productive cough (47.1%) and dry cough (35.5%). Thirteen (76.5%) patients had dyspnea or respiratory distress, five (29.4%) had shock, and four (23.5%) had acute kidney injury. Seventeen (100.0%) patients had lymphopenia. Involvement of both lungs was found by chest radiography in 14 (82.4%) patients at presentation. Fifteen (88.2%) patients were hospitalized. The median times from illness onset to hospitalization and to diagnosis confirmation were both six days. Eleven (64.7%) patients were admitted to the intensive care unit. Sixteen (94.1%) patients were treated with oseltamivir. The median time from illness onset to oseltamivir treatment was six days. Among six patients for whom the duration of viral shedding was available, the median duration of viral shedding after oseltamivir treatment was 17 days. The median time from illness onset to death was 11 days. Refractory hypoxemia accounted for most deaths. The clinical and epidemiologic characteristics in the Shanghai fatal series of patients do not differ from other reports of H7N9 patients in China. This investigation reflects a delay in the diagnosis and antiviral treatment of H7N9 patients in the early stage of the epidemic in Shanghai. Late antiviral treatment and a long duration of viral shedding may be associated with a fatal outcome in these patients.