Mechanisms of cross-species transmission of H7N9 avian influenza virus and its pathological features in airway epithelium: Research progress / 解放军医学杂志

ABSTRACT

H7N9 avian influenza is a new subtype of avian influenza, first found in the Yangtze River Delta at the end of February 2013. H7N9 avian influenza, infection in human is transmitted through the respiratory airway, causing acute respiratory infectious disease. Due to the species barrier, H7N9 avian influenza virus only infect human via birds occasionally under very specific circumstances, and at present, there is no exact evidence of H7N9 avian influenza virus transmission between humans. However, H7N9 avian influenza remains a continuous public health threat. So far, China has had six outbreaks of H7N9 avian influenza. A total of 1567 cases of H7N9 influenza virus infection have been reported to WHO, including 615 deaths. When H7N9 avian influenza virus infects the human body, their primary target of infection is the respiratory mucosal epithelial cells. Therefore, the respiratory epithelium plays a key role in the process of virus transmission and infection. Hence, the main purpose of this review is to collate the current understanding of immune responses and their corresponding molecular mechanisms of mucosal damage caused by H7N9 avian influenza infection, and how it contributes to cross species human infection.