Influenza virus is one of the most prevalent respiratory viruses and responsible for annual epidemics as well as occasional pandemics with sometimes devastating outcomes. The virus is classically considered to mainly infect the upper, and occasionally lower, respiratory tract, clinically giving rise to upper respiratory symptoms and pneumonias. Furthermore, associations between respiratory viral infections and the development of neuroinflammatory and neurodegenerative diseases have been postulated. Influenza viruses have, in terms of virus-host interactions, been classified into viruses that circulate in avian hosts and viruses circulating in other hosts including humans. In addition, viruses with low or high pathogenicity are distinguished. Review articles are the summary of current state of understanding on a particular research topic. They analyze or discuss research previously published by scientist and academicians rather than reporting novel research results. Review article comes in the form of systematic reviews and literature reviews and are a form of secondary literature. Systematic reviews determine an objective list of criteria, and find all previously published original research papers that meet the criteria. The concept of "review article" is separate from the concept of peer-reviewed literature. It is possible for a review to be peer-reviewed, and it is possible for a review to be non-peer-reviewed.
Last date updated on June, 2014