Entry into the Host Gastrointestinal tract-ahostile environment; gastric acid, bile salts, etc Genitourinary tract-relatively less hostile than the above, but less frequently exposed to extraneous viruses Conjunctiva-an exposed site and relatively unprotectedEntry into the Host • Gastrointestinal tract- a hostile environment; gastric acid, bile salts, etc • Genitourinary tract-relatively less hostile than the above, but less frequently exposed to extraneous viruses (?) • Conjunctiva - an exposed site and relatively unprotected