"Heterosubtypic immunity (HSI) is defined as cross-protection to infection with an

influenza A virus ''Influenza A virus'' (''Alphainfluenzavirus influenzae'') or IAV is the only species of the genus ''Alphainfluenzavirus'' of the virus family '' Orthomyxoviridae''. It is a pathogen with strains that infect birds and some mammals, as well as c ...

serotype A serotype or serovar is a distinct variation within a species of bacteria or virus or among immune cells of different individuals. These microorganisms, viruses, or Cell (biology), cells are classified together based on their shared reactivity ...

other than the one used for primary infection." In

layman's terms Plain English (also referred to as layman's terms) is a mode of writing or speaking the English language intended to be easy to understand regardless of one's familiarity with a given topic. It usually avoids the use of rare words and uncommon euph ...

: an 'infection with "seasonal" influenza A viruses could induce

immunity Immunity may refer to: Medicine * Immunity (medical), resistance of an organism to infection or disease * ''Immunity'' (journal), a scientific journal published by Cell Press Biology * Immune system Engineering * Radiofrequence immunity ...

against unrelated sub-strains.'

Leicester Mercury The ''Leicester Mercury'' is a British regional newspaper for the city of Leicester and the neighbouring counties of Leicestershire and Rutland. The paper began in the 19th century as the ''Leicester Daily Mercury'' and later changed to its pre ...

''Winter flu could help protect kids'', 30 October 2009

References

{{DEFAULTSORT:Influenza A Virus Immunology Influenza vaccines Influenza A virus