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

Song, Joon Young; Noh, Ji Yun; Lee, Jacob; Woo, Heung Jeong; Lee, Jin Soo; Wie, Seong-Heon; Kim, Young Keun; Jeong, Hye Won; Kim, Shin Woo; Lee, Sun Hee; Park, Kyung-Hwa; Kang, Seong Hui; Kee, Sae Yoon; Kim, Tae Hyong; Choo, Eun Ju; Lee, Han Sol; Choi, Won Suk; Cheong, Hee Jin; Kim, Woo Joo

In this study, no human case of A/H7N9 influenza infection was found in Korea among travelers. However, Korea is geographically close to China, and travels to China are common. In addition, there is a possibility of A/H7N9 influenza influx due to increasing trade between Korea and China. Of note, human A/H7N9 influenza infection cases increased in number and the epidemic areas were extended to the northern and western regions (Beijing, Jilin, Liaoning, Gansu, Chongqing, Guizhou, and Sichuan) of China during the 2016-2017 influenza season. During the fifth epidemic wave since October 2016, the number of human cases with avian influenza A/H7N9 infection was greater than the numbers of those reported in earlier waves. 13 Accordingly, the risk of human A/H7N9 influenza infection influx has substantially increased in Korea. Therefore, the Korean A/H7N9 influenza surveillance system should be strengthened and maintained. Since the A/H7N9 influenza infection is accompanied by pneumonia in most cases, it is necessary to expand the surveillance system by including larger number of university hospitals.