Non-invasive Clostridia

Question 1

Two main types of non-invasive clostridia

Answer 1

C. botulinum & C. tetani Botulism & Tetanus

Question 2

Botulism - Disease info

Answer 2

Neuroparalytic intoxication - FLACCID paralysis - 7 protein neurotoxins (A-G, C&D most common)

Question 3

Botulism - Species affected

Answer 3

Ruminants - Horses - Mink - Fowl / Waterfowl

Question 4

Botulism -Toxins

Answer 4

BONT - endopeptidases bind to cholinergic nerve cells, decreases release of ACh

Question 5

Botulism - Reservoir

Answer 5

Dead animals, spores germinate, generate toxin. Ingested by carrion eaters or contaminate the environment

Question 6

Botulism - Pathogenesis

Answer 6

BONT ingested, absorbed into GI –> blood –> NMJ of cholinergic nerves/synapses –> Hydrolyzes “docking protein” –> synapses degenerate leading to flaccid paralysis (death from respiratory failure! Numb diaphragm)

Question 7

Botulism - Clinical signs

Answer 7

Recumbency - Extrusion of tongue - Unable to swallow - Birds have limberneck - Shaker foal syndrome (type B botulinum)

Question 8

When I say Shaker Foal syndrome, you say

Answer 8

Type B botulinum - Clostridium botulinum

Question 9

When I say limberneck in birds, you say

Answer 9

Clostridium botulinum

Question 10

When I say a cow is recumbent with its tongue sticking out and can’t swallow, you say..

Answer 10

Clostridium botulinum

Question 11

Tetanus - General Disease info

Answer 11

Neuroparalytic intoxication - CLONIC / TONIC sustained convulsions - SPASTIC paralysis

Question 12

Tetanus - Toxins

Answer 12

TENT=Tetanospasmin - Zinc endopeptidases bind neurons, release GABA & glycine, major inhibitory neurotransmitters. Takes weeks-months to generate. Good vaccine because antigenically uniform

Question 13

Ascending tetanus

Answer 13

Follows retrograde - Intra-axonal transport - dogs & cats because not highly susceptible

Question 14

Descending tetanus

Answer 14

In highly susceptible species (humans & horses) dissemination via vascular channels to remote nerve endings

Question 15

Tetanus Transmission

Answer 15

Inoculation of spores into wound - often puncture wounds, anaerobic

Question 16

Tetanus susceptible species

Answer 16

All mammals - Particularly humans, horses, swine, ruminants. Carvinores less

Question 17

Tetanus clinical signs

Answer 17

Retraction of 3rd eyelid - Ears erect - Teeth grinding - tail stiffness - “Sawhorses”

Question 18

When I say sawhorses, you say…

Answer 18

Tetanus!

Question 19

When I say drumstick bacteria, you say…

Answer 19

Noninvasive clostridia! C. tetani