Читать книгу Principles of Virology, Volume 2 - Jane Flint, S. Jane Flint - Страница 63

 Three requirements must be met to ensure successful infection of an individual host: a sufficient number of infectious virus particles, access of these particles to susceptible and permissive cells, and uneducated or dampened local antiviral defenses.

 Common sites of virus entry include the respiratory, alimentary, and urogenital tracts; the outer surface of the eyes (conjunctival membranes or cornea); and the skin.

 Each of these portals is equipped with anatomical or chemical features that limit viral entry and infection.

 Spread beyond the site of infection depends on the initial viral dose, the presence of viral receptors on other cells, and the relative rates of immune induction and release of infectious virus particles.

 Disseminated infections typically occur through the bloodstream, although some viruses can be transported by the peripheral nervous system.

 Effective transmission of virus particles from one host to another depends on the site of shedding and the concentration of released particles.

 Viral transmission to a new host usually occurs through body fluids, including respiratory aerosols and secretions, blood, saliva, semen, urine, and milk.