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HPV Pathogenesis7,8
HPV Pathogenesis/Equilibrium
• In biological evolution, HPVs are successful infectious agents. They induce persistent infections without frequent and serious complications for the host and shed virions for transmission to other naive individuals. They reach a balanced state where the host usually is not seriously disadvantaged by the HPV infection, and the virus is not too limited in reproducing by the host's immune response. To achieve this lifestyle and to maintain a state of equilibrium, the HPV must avoid the host's defense systems.
• Many factors contribute to evading immune pools, in particular:
• no viral‐induced cytolysis or necrosis; no inflammation; no blood‐borne or
viremic phase; infection is exclusively intraepithelial;
• free virus particles are shed from the surface of squamous epithelia with poor access to vascular and lymphatic channels and to lymph nodes where immune responses are initiated only minimal amounts of replicating virus exposed to immune defenses;
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