Hospital-based Influenza Morbidity and Mortality (HIMM) Surveillance for A/H7N9 Influenza Virus Infection in Returning Travelers

Abstract

Since 2013, the Hospital-based Influenza Morbidity and Mortality (HIMM) surveillance system began a H7N9 influenza surveillance scheme for returning travelers in addition to pre-existing emergency room (ER)-based influenza-like illness (ILI) surveillance and severe acute respiratory infection (SARI) surveillance. Although limited to eastern China, avian A/H7N9 influenza virus is considered to have the highest pandemic potential among currently circulating influenza viruses. During the study period between October 1st, 2013 and April 30th, 2016, 11 cases presented with ILI within seven days of travel return. These patients visited China, Hong Kong, or neighboring Southeast Asian countries, but none of them visited a livestock market. Seasonal influenza virus (54.5%, 6 among 11) was the most common cause of ILI among returning travelers, and avian A/H7N9 influenza virus was not detected during the study period.

The National Influenza Surveillance System of Korea

“…The HIMM data have been used to analyze the clinical course of severe influenza [2627], influenza disease burden [28], characteristics of influenza viruses that caused severe clinical course [29], influenza vaccine effectiveness, and so on. In addition to surveillance for severe influenza, there is surveillance for avian influenza viruses that can cause human infection such as A/H7N9 and A/H5N1 [30]. Currently, the HIMM surveillance system continues to be operated at nine hospitals.…”