Equine infectious respiratory disease

Question 1

Describe how influenza A virus is spread in horses

Answer 1

aerosol ( and fomites)
highly infectious

Question 2

describe the pathogenesis of influenza A virus .in horses

Answer 2

infection of respiratory epithelial cells (URT)
nasopharyngeal virus shedding
destroys cilia

Question 3

List the clinical signs of influenza A virus in horses

Answer 3

Fever
cough
nasal discharge (serous, may become mucopurulent- if secondary bacterial infection)

Question 4

Describe how to treat / prevent influenza A virus in horses

Answer 4

vaccines available
nursing care and anti-inflammatory medication (antibiotics for secondary infection)

Question 5

Describe how to diagnose influenza A virus in horses

Answer 5

Nasal swab- detection of viral antigen (ELISA), detection of RNA (RT-PCR)
serum samples - detection of antibodies (serology)

Question 6

Describe how Equine herpesvirus- 1 &4 is spread

Answer 6

inhalation of aerosol
contact with infected fomites
reactivation from latency

Question 7

describe the common clinical signs of Equine herpesvirus- 1 &4

Answer 7

fever
occasional mild cough
slight nasal discharge
poor performance (age. immunity dependent)

Question 8

describe the occasional clinical signs of Equine herpesvirus- 1 &4

Answer 8

abortion / sick neonatal foal
neurological disease- equine herpesvirus myeloencephalopathy EHM

Question 9

describe hoe to treat/ prevent Equine herpesvirus- 1 &4

Answer 9

vaccines avaliable
rest in athletic animals
EHM: nursing care and anti-inflammatory medication

Question 10

Describe how to diagnose Equine herpesvirus- 1 &4

Answer 10

nasal swab - viral DNA- PCR
blood samples- virus isolation in tissue culture, Detection of antibodies by complement fixation test

Question 11

DEscribe how Equine viral arteritis (EVA) is spread

Answer 11

respiratory
venereal
congenital routes
indirect means (fomites)

Question 12

describe the clinical signs of Equine viral arteritis (EVA)

Answer 12

often asymptomatic
fever
nasal discharge
loss of appetitie
respiratory distress
skin rash
muscle soreness
conjunctivitis
depression

Question 13

describe how to diagnose Equine viral arteritis (EVA)

Answer 13

Virus detection in body secretions or fluids, whole blood, or tissues by virus isolation, RT-PCR and in situ hybridization

ELISA used for routine screening of horses that show no clinical signs of infection, e.g. for pre-breeding or sales requirements.

Question 14

Describe how to treat/ prevent equine viral arteritis

Answer 14

General supportive care during the acute phase of infection.
There is no treatment to eliminate persistent infection in stallions.
Inactivated virus vaccine

Question 15

What parasite causes lungworm in horses

Answer 15

Dictyocaulus arnfieldi

Question 16

describe how horse lungworm is spread

Answer 16

ingestion of L3 larvae from faeces/ pasture
donkeys main source of pasture contamination

Question 17

describe how to diagnose lungworm in horses

Answer 17

First-stage larvae L1 in faeces (infrequent & few)
Tracheal wash for eggs, larvae & WBCs
[failure of antibiotic therapy, season, history]- diagnosis of elimination

Question 18

Descrieb the clinical signs of lungworm in horses

Answer 18

moderate-severe coughing (exercise)
mucopurulaent exudate

Question 19

Describe the pathogenesis of equine viral arteritis

Answer 19

invades upper and lower resp tract
stallions can become persistently infected- become carriers

Question 20

describe the pathogenesis of equine herpesvirus

Answer 20

infection of resp epithelial cells

Question 21

describe how to control outbreaks of resp diseases in horses

Answer 21

disinfection
isolation
submission (samples for diagnosis)
hygienic procedures

Question 22

List 4 common hurdles in the face of outbreak with horse resp disease

Answer 22

Slow identification of affected horses
Delay in diagnostic test results
Owner compliance
Declaration of end of outbreak?

Question 23

what is the main source of pasture contamination with lungworm

Answer 23

donkeys

Question 24

Describe how we can treat lungworm in horses

Answer 24

moxidectin or ivermectin

Question 25

Describe how to diagnose equine lungworm

Answer 25

First-stage larvae L1 in faeces

tracheal wash for eggs, larvae and WBCs