Topic 6: Canine enteritis caused by Parvoviruses

Question 1

Canine parvovirus CPV

Answer 1

WW, first appearinged in Australia and USA, 1977

VP2 protein, mutations of some epitopes )abcd)
highly contagious, common cause of acute infectious GI disease in young dogs

Non enveloped, ssDNA virus

Resistant to detergents, disinfectants and can persist in environment for 5 months

CPV1; non pathogenic
CPV2 since 1977, CPV2a and 2b subtypes

may ave arisen from a feline panleukopenia virus, or related parvovirus

Question 2

Susceptible species CPV

Answer 2

Dogs, and other canids, dog wolf fox

also cats
cats can be infected with CPV2 subtypes, accounts for 10% of all feline panleukpaenia

Question 3

Epidemiology of CPV2

Answer 3

Young, unvaccinated, imcompletwly Vx dogs 6w - 6m are most susceptible

maternal protection for first few weeks

contact with an infected animal of faeces , fomites in environ

puppies 3-8weeks, sudden death, myocardial damage and high mortality (zenkers)

Puppies over 8 weeks and adults, Enteritis, haemorrhage, mortality 10%

Seropositive because of Vx or infection

Question 4

Pathogenesis of CPV2

Answer 4

shed in faeces within 4-5 days of exposure and through illness (can shed before CS)

shedding 3-4 days PI, peaks day 7, stops 3 weeks PI

PO infection, X lymphoid tissue or oropharynx, haetaogenous dissemination (viremia), systemic illness

CPV2 targets and destroys rapidly divinding cells
- SI crypt epithelium, epi necrosis, villous atrophy, implored resorptive capacity, disrupts but barrier

• lymphopeotic tissue, L cells of bone marrow, spleen, thymus an LN –> leuko and neutropenia
• myocardial cells in young animals

Question 5

CS CPV2

Answer 5

after 2-4d incubation

non specific l fever, lethargy, anorexia, depression

Acute gastroenteritis, vomiting, severe bloody drx, bloody gastroenteritis, haemorrhages, abdominal pain, dehydration, weight loss

outcome depends on age and immune status

Question 6

DX of CPV

Answer 6

CS and anemesis (age, Vx history)
Viral detection in feaces,(HA, PCR, ELISA)
- +ve 10-15d after use of I’ve vaccine
basophilic nuclear inclusion bodies in intestinal cells
AB detection, HAI, VN, Elisa, if present in high for increasing amounts

Low WBC count, leukopenia, neutropenia

Biochemical profile (elevated Liver enzymes, lymphopaneia, electrolyte imbalances and urinalysis

many older dogs will be seropostive

Question 7

Tx of CPV

Answer 7

symptomatic treatment, rehydration, liquid replacement, anti emetics, colloid tx

prevent 2º bacterial infection with Antibiotics

Hyperimmune serum, before CS if we suspect disease early

Question 8

Prevention, Vx CPV

Answer 8

General hygiene and sanitation

Vx, live attenuated polyvalent vaccine, inactivated polyvalent

1st dose 8-9w
2nd 12w 
3rd 16
4th 1 year after last dose 
repeat every 3 years after last dose 

maternal protection up to 3-4 months

Question 9

DDX CPV

Answer 9

Coronas virus
CCov 1; vomiting and watery drx in young dogs
CCoV 2; bloody enteritis , vomiting and ataxia in dogs 1.5-2 months

herpesvirus; fatal in dogs under 2-3 weeks, 80% mortality up to 1 w of age. bloody enteritis and or respiratory symptoms

Rota virus - milder CS, bloody drx is rare