Infectious Diseases

Question 1

What is the aetiology of Canine Parvovirus?

Answer 1

Canine Parvovirus (CPV) belongs to Parvovirus group. CPV2 is the most common strain.

Question 2

Describe the Pathophysiology of Canine Parvovirus

Answer 2

Virus has an affinity for rapidly dividing cells in the gut wall (e.g. in the Crypts of L) and lymphoid tissue (e.g. bone marrow). Multiplication of the virus leads to the destruction of the intestinal lining and causes inability to absorb nutrients. In advanced cases the intestinal lining is so damaged, bacteria from the gut can invade the bloodstream. The affects on the bone marrow and lymph nodes will suppress the immune system and cause leucopenia.

Question 3

What are the main clinical signs of Canine Parvovirus?

Answer 3

Depression, Anorexia, Severe vomiting, haemorrhagic diarrhoea, pyrexia, severe weight loss, dehydration, shock (pale MM etc.)

Question 4

What can Canine Parvovirus cause in rare cases in puppies?

Answer 4

Destruction of myocardial cells causing sudden death or heart failure in puppies.

Question 5

How can you diagnose Canine Parvovirus?

Answer 5

History and Clinical signs (e.g. is the dog vaccinated)
Faecal Test ELISA -snap parvo test - looking for CPV2 antigen in faeces.
PCR (faecal sample)- detects CPV2 DNA in faeces - sent to external lab and can take 3+ days. (helpful to confirm cases)

Question 6

What are the pros and cons of an ELISA snap test?

Answer 6

Quick - rapid results
Easy to use
Cheaper

Can give false negatives

Question 7

What is a PCR?

Answer 7

Polymerase chain reaction. Isolates Viral DNA in a sample e.g. faecal.

Question 8

What does ELISA stand for?

Answer 8

Enzyme-linked Immunosorbent Assay

Question 9

What are the pros and cons of PCR?

Answer 9

Reliable Results
Early detection

Sent to an external lab - takes 3+ days

Question 10

What causes Feline Leukaemia Virus (FeLV)?

Answer 10

Retrovirus from the oncornavirus (cancer-causing)

Question 11

Describe the pathophysiology for FeLv

Answer 11

Virus replicates in the lymphoid tissue and enters lymphocytes and monocytes where it is then transported around the body. It eventually enters the bone marrow.
A persistent infection can lead to immune suppression, anaemia or neoplasia

Question 12

What are the clinical signs of FeLV?

Answer 12

Depends on cats immune system.
Immunosuppression
Recurrent infections (e.g. UTI)
Anaemia
Development of tumours
Poor prognosis (3-4yrs to live)
Lethargy
Diarrhoea

Question 13

How can you diagnose FeLV?

Answer 13

Primary differential diagnosis for FeLV is FIV.
ELISA serum test for antigen (repeat in 12wks)
PCR - to confirm results - isolate viral genetic material

Question 14

What is the correct term for Cat Flu?

Answer 14

Feline Upper Respiratory Disease (FURD)

Question 15

What is the aetiology of FURD?

Answer 15

Can be caused by a number of agents:
- feline herpesvirus 1 (FHV1) *
- feline calicivirus (FCV) *
- Bordetella bronchoseptica
Chlaumydophila felis

*most common

Question 16

What is the Pathophysiology of Feline Herpesvirus 1 (FHV1) ?

Answer 16

Replicates in the epithelial tissue of the upper respiratory tract and ocular systems. Leads to epithelial necrosis where bacteria can then invade leading to secondary infections.
Causes irritation in pharynx, larynx and trachea. Can also cause reproductive and dermatological signs.

*Also test for FeLV and FIV as underlying cause

Question 17

What is the pathophysiology of Feline Calicivirus (FCV) ?

Answer 17

Similar trophism for upper respiratory epithelium as FHV1, however causes milder upper respiratory tract symptoms.
Causes characteristic lesions in the oral cavity leading to ulcerations and erosive lesions and red tongue.
Can cause pneumonia in severe cases

Question 18

What are the clinical signs of FHV1?

Answer 18

anorexia, pyrexia, depression, sneezing, conjunctivitis, hypersalivation, ocular and nasal discharge, corneal ulcer.

Question 19

What are the clinical signs of FCV?

Answer 19

oral ulceration, chronic stomatitis (inflammation of the mouth), sneezing, pyrexia

In rare cases can cause inflammation in joints causing lameness

Question 20

How is FURD diagnosed?

Answer 20

History and Clinical signs
Isolation of causal agent by swab of pharynx, nose or conjunctiva (may not get a positive result with a carrier cat as not actively shedding)