Animal Disease L4

Routes of Infection

Ingestion

Inhalation

Direct Contact

Ascending

Hematogenous

Ingestion Barriers

Saliva/Acid

Tonsils/Peyers Patch (immune tissue)

Mucus

Epithelium

Mucosal Barrier Breach =

Local intestinal inflammation

Intestinal Wall Breached =

thickness

Ingestion Infection Pathways

Lymphatic → Portal Tract → Liver

Blood Vessels → Systemtic

Intestinal Wall Breach → Peritonitis

Inhalation Barriers

Turbinates

Mucus

Epithelium

Inhalation Infection Depends on

Size, Shape, Weight, Gravity (biped vs quadruped)

Ascending Infection

Movementt up tubular organ against normal direction of flow

Ascending Infection Urinary

Urethra → Bladder or Ureters → Kidney

Ascending Infection Biliary

Intestine → bile duct → liver

Ascending Infection Reproductive

Vagina → Uterus

Direct Contact Lymph Path

Lymphatic access → lymph nodes → spleen

Hematogenous

Spread via circulation, typically to all tissues

Direct Transmission

Passed via physical contact or droplet sprays

Indirect Transmission

Vehicle, Vector, or Fomite

Fomite Transmission

Inanimate objects contaminated with diseases

Vector Mechanical Transmission

Passive transmission through physical contact

Vector Biological Transmission

uptakes the agent, replicates or develops agent, then transfers to host