The host range or host specificity of a parasite is the collection of hosts that an organism can utilize as a partner. In the case of human parasites, the host range influences the epidemiology of the parasitism or disease. For instance, the production of antigenic shifts in Influenza A virus can result from pigs being infected with the virus from several different hosts (such as human and bird). This co-infection provides an opportunity for mixing of the viral genes between existing strains, thereby producing a new viral strain. An influenza vaccine produced against an existing viral strain might not be effective against this new strain, which then requires a new influenza vaccine to be prepared for the protection of the human population
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Famous quotes containing the words host and/or range:
“Nothing is quite so wretchedly corrupt as an aristocracy which has lost its power but kept its wealth and which still has endless leisure to devote to nothing but banal enjoyments. All its great thoughts and passionate energy are things of the past, and nothing but a host of petty, gnawing vices now cling to it like worms to a corpse.”
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—Administration in the State of Texa, U.S. public relief program (1935-1943)