Immune response to H5N1 virus infection in humans

Abstract

Background: The menace of H5N1infection in humans till date is a worldwide problem. H5N1 influenza viruses are prevalent in poultry in  Asia and have recently spread to other continents like Africa and Europe. H5N1 influenza virus infections in the human population are  rare due to their inefficient direct human-to-human transmission. H5N1 infection in human is followed by strong inflammatory response  which is usually characterized by elevated levels of cytokines and chemokines in serum, believed to be important in the severe  pathogenesis that develops in a high proportion of patients. Of particular concern are the elevated levels of tumor necrosis factor-alpha,  a protein associated with tissue destruction at sites of infection. H5N1 virus causes severe influenza disease in humans, manifested by  acute respiratory distress syndrome, multi-organ failure, and high mortality rates of 60%.

Aim: To understand the human immune  responses to H5N1 so that effective control of severe influenza disease caused by H5N1 and rationally design of new immunotherapies and vaccines can be achieved. 

Conclusion: This review discussed the human immune responses to H5N1 viral infection, with emphasis on  H5N1 virulence factors and their impact on the modulation of the innate immunity in humans.