11. Picornaviral infectious diseases, Foot and mouth disease

Question 1

Describe Picornavirus

Answer 1

• Belongs to family Picornaviridae
• RNA virus
• Very resistant and cause big economical losses.
• Many subtypes whereby production of vaccines are difficult

Question 2

Describe diseases that Picornavirus are responsible for

Answer 2

• Foot and mouth disease - Ru –> contagious & OIE listed
• Swine vesicular disease - Su –> Contagious, OIE listad & ZOONOTIC
• Avian encephalomyelitis - Birds –> CNS symptoms. High morbidity and mortality.
• Duck viral hepatitis - ducklings –> liver lesions, 100% mortality
• Turkey viral hepatitis - turkey –> liver lesions, lower mortality.

Question 3

What are two important things to mention about foot and mouth disease?

Answer 3

Contagious and OIE listed

Question 4

What is the agent responsible for causing foot and mouth disease in ruminats?

Answer 4

FMD virus from Family Picornaviridae, genus Apthovirus

Question 5

What are susceptible hosts for foot and mouth disease?

Answer 5

Cloven-hoofed animals - Ruminants and Pig

Question 6

What does foot and mouth disease cause in host?

Answer 6

Lesions of oral mucous membrane (blister on tongue) and foots (between hoves)
High morbidity, low mortality (in adult). Shed virus for a long time (over 2 years in cattle)

Question 7

What is the transmission of picornavirus?

Answer 7

Horizontal - in all excretions from infected animals (feces, urine, saliva, nasal discharge, milk, semen)

Question 8

What are clinical signs in infected animal with foot and mouth disease?

Answer 8

Range from mild / inapparent to severe:
- More severe in cattle
- Blisters on nose, tongue or lip, in oral cavity, between toes, above hooves, on teats

General: Loss of condition, lameness, fever, depression, hypersalivation, loss of appetite, weight loss, retardation growth, drop in milk production

Question 9

How is foot and mouth diagnosed?

Answer 9

• According to diagnosis and history - difficult to differentiate between other vesicular diseases
• RT- PCR with sample from vesicles
• Serological tests: Check for Ab by VNT, ELISA - check for Ab or Ag

Question 10

What is treatment of foot and mouth disease?

Answer 10

No treatment.
Slaughter in highly infected areas. With 3km radius protective zone!!

Question 11

How can foot and mouth disease be prevented?

Answer 11

• Vaccination
• Hygiene measurements
• Quarantine
• Control of movement of animals