Vesicular Diseases

Question 1

4 important vesicular diseases

Answer 1

1) Vesicular stomatitis
2) vesicular exanthema of swine
3) Foot and Mouth Disease
4) Swine vesicular disease

These 4 diseases cannot be clinically differentiated from each other

All 4 are reportable diseases

Question 2

Which of the vesicular diseases are in the US

Answer 2

Only Vesicular exanthema of swine (VES)

Has not occurred in US for 4 decades

Question 3

Vesicular stomatitis virus (VSV) family

Answer 3

VSV is vesiculovirus belonging to the virus family Rhabdoviridae

Question 4

Vesicular stomatitis virus species affected and location of vesicles

Answer 4

Horses, cattle, pigs, man

Vesicle in mouth, feet, and on teats

Can also infect man (influenza-like disease)

Question 5

2 types of vesicular stomatitis virus serotypes

Answer 5

Indiana and New Jersey

New Jersey serotype is more widespread and virulent

Question 6

Transmission of Vesicular Stomatitis Virus

Answer 6

Limited to the western hemisphere

Enzootic in Central and South America, and in Ossabow Island (near Georgia)

In the US we have periodic incursions of the virus with disease outbreaks occurring in LATE SUMMER/FALL, especially in the western states

Transmitted primarily by SAND FLIES AND BLACKFLIES

Question 7

Where do we see outbreaks of vesicular stomatitis virus?

Answer 7

Along river drainage

Low-lying areas receiving heavy rainfall and high vector population (central America)

Outbreaks n US is believed to be WINDBORNE, initiated by infected carrier insects blown up from Central America

Question 8

Transmission of vesicular stomatitis virus during an outbreak

Answer 8

Through mucosa or broken skin
-saliva and vesicular fluid from infected animals is very infectious

Virus remains viable on milking machine parts, in soil, vegetation, especially in cool weather

Question 9

Clinical signs of vesicular stomatitis virus

Answer 9

Fever, anorexia, excess salivation first signs

In horses and cattle, see vesicle on dorsum of tongue, dental pads, buccal mucosa, teats, and coronary bands
-when vesicle rupture, it leaves a small shallow erosion/ulcer… lameness is then seen

In swine, most commonly see vesicle on shouted feed, causing lameness

In horses tongue lesions are most pronounced

Question 10

Morbidity and mortality of vesicular stomatitis virus

Answer 10

10-80% morbidity, 0% mortality

Question 11

Pathogenesis of Vesicular stomatitis virus

Answer 11

Virus gains entry through damaged skin (insect bites, trauma of milking, eating fibrous foods, etch)

Cause a viremia and virus distributes in skin epithelium > replication > vesicle formation

Lesions form in areas of skin that are irritated (tongue of horse, snout and feet of pigs)

Question 12

Diagnosis of Vesicular Stomatitis virus

Answer 12

SEASONAL DISEASE- seasonal disease
REPORTABLE DISEASE

Samples to submit are vesicular fluid and paired serum samples for RT-PCR and virus isolation

Question 13

Treatment of Vesicular stomatitis virus

Answer 13

Control movement of sick animals… usually recover in 3-4 days

Vaccination is practiced in high producing dairy herds

Question 14

Vesicular stomatitis virus infects humans. Classify the virus

Answer 14

epizootic

Question 15

Vesicular Exanthema of Swine (VES) characteristics

Answer 15

Acute, febrile, contagious disease of SWINE characterized by formation of vesicle on snout, mouth, and on the feet

Morbidity is high, mortality is low

Clinically indistinguishable from other vesicular disease

Question 16

What causes Vesicular Exanthema of Swine?

Answer 16

A calicivirus

Question 17

Where is Vesicular Exanthema of swine seen?

Answer 17

Outbreaks in Iceland and Hawaii

Mostly seen In US

Question 18

Serotypes of vesicular Exanthema of Swine

Answer 18

14 serotypes of viruses isolated from marine mammals (San Miguel Sea Lion Virus)

Question 19

Diagnosis of VES

Answer 19

Diagnosed with fluid from vesicle - RT-PCR

Question 20

Prevention of vesicular exanthema of swine

Answer 20

Quarantine, slaughter all animals, restrict animal movement, disinfect

Vaccination is available

Question 21

Is virus zoonotic?

Answer 21

YES!!

Question 22

Where did vesicular exanthema of swine come from?

Answer 22

Marine mammals off the coast of california

Question 23

San Miguel Sea Lion Virus

Answer 23

Virus closely related to vesicular exanthema of swine, but is not identical
-distinguishable by virus neutralization test

• virus has been isolated from sea lions and fur seals, and AB found in whales, fish, and feral swine
• virus causes VES-like disease in pigs

In sea lions, causes abortions and vesicular lesions in mouth and on flippers

-marine/terrestrial transmission suggested (feeding marine mammals to swine)

Question 24

Foot and Mouth Disease (FMD) characteristics

Answer 24

One of the most important economic and political diseases in the world

Affects cloven-footed animals (not horses)

Characterized by vesicles in the mouth and on the feet of animals, and responsible for tremendous loss in production

Virus persists in meat products

Question 25

Foot and Mouth Disease family

Answer 25

Aphtovirus belonging to the virus family Picornaviridae

Question 26

Types of foot and mouth disease

Answer 26

7 major types | 70 serotypes- enough Ag difference that vaccination against one does not protect you against another serotype

Question 27

Species affected by foot and mouth diseas

Answer 27

Cloven footed animals- cattle, pigs, sheep/goats, wild ruminants

Question 28

Morbidity and mortality of foot and mouth disease

Answer 28

High morbidity but low mortality Recovered cattle remain carriers with virus recovered in epithelial cells lining pharynx and esophagus

Question 29

What are outbreaks of Foot and Mouth disease associated with?

Answer 29

Illegal importation of infected meat products or animals FMDV survives in meat products

Question 30

How do you inactivate the virus in meat?

Answer 30

Acidity/ pH below 7.0 Importation of muscle cuts onloy is allowed

Question 31

Transmission of foot and mouth disease

Answer 31

Virus in saliva and most body fluids of acutely ill animals Spread by direct contact with infected animals and vomited, by inhalation, and by ingestion

Question 32

Clinical signs of foot and mouth disease

Answer 32

In cattle, starts with lameness, smacking of lips, and salivation Vesicle may appear in mouth, on muzzle, on feet, on teats, and on udder Vesicle start as blanched areas, rupture, and complete healing after 2 weeks In calves, death can occur due to myocarditis IN PIGS: lameness and vesicle on snout

Question 33

Diagnosis of Foot and Mouth disease

Answer 33

History, clinical signs Submit vesicular fluid and epithelial covering

Question 34

Control/prevention of foot and mouth disease

Answer 34

Good immunity after recovery from disease Restrict importation of semen, meat products, hides, animals... or test before importation Inactivated vaccine available

Question 35

What is the VIA antigen for foot and mouth disease

Answer 35

Virus infection associated antigen (VIA Ag) Animals recovering from FMD will have AB to VIA Ag- VIA Ag is the RNA polymerase synthesized during virus replication- animals vaccinated with killed vaccine have no AB to the VIA Ag

Question 36

Swine Vesicular Disease (SVD)

Answer 36

Caused by an enterovirus of the family Picornaviridae (Porcine enterovirus type 9) Disease of pigs characterized by vesicular lesions in the mouth and feet NOT IN US