Insect vectors 4. Fecal-oral transmission B. Attachment 1. Often at mucosal surfaces 2. Often requires specific attachment sites 3. Site of attachment is often initial replication site C. Invasion 1.
Many pathogens invade tissues from their sites initial infection.
Bacterial factors can promote invasion, eg exoenzymes. Defective host defenses allow for invasion. D. Toxin production 1. Endotoxins-part of cell wall 2. Entire disease can be due to toxin 4.